A possible role for RNA polymerase in the initiation of M13 DNA synthesis. The conversion of single-stranded DNA of bacteriophage M13 to the double-stranded replicative form in Escherichia coli is blocked by rifampicin, an antibiotic that specifically inhibits the host-cell RNA polymerase. Chloramphenicol, an inhibitor of protein synthesis, does not block this conversion. The next stage in phage DNA replication, multiplication of the doublestranded forms, is also inhibited by rifampicin; chloramphenicol, although inhibitory, has a much smaller effect. An E. coli mutant whose RNA polymerase is resistant to rifampicin action does not show inhibition of M13 DNA replication by rifampicin. These findings indicate that a specific rifampicin-RNA polymerase interaction is responsible for blocking new DNA synthesis. It now seems plausible that RNA polymerase has some direct role in the initiation of DNA replication, perhaps by forming a primer RNA that serves for covalent attachment of the deoxyribonucleotide that starts the new DNA chain.


Isolation of catenated and replicating DNA molecules of colicin factor E1 from minicells. Various catenated and replicating molecules of colicin E1 isolated from minicells have been identified in regions of neutral sucrose density gradients or cesium chloride-ethidium bromide density gradients. These colicin molecules have been found in those regions of the gradient where pulse-labeled DNA accumulates.


An unfolding discovery.

An unfolding discovery.


The distribution and action in photosynthesis of several forms of chlorophyll.


The seventy-fifth anniversary of Francis Henry William's clinical application of the X-ray.


Surgery for chronic asynergy of the left ventricle: a current appraisal.


Surgical therapy for early complications of myocardial infarction.


Surgical treatment of congenital coronary artery fistula.


Unsuspected depressed cardiac output following blunt thoracic or abdominal trauma.


Hemodynamic alterations caused during orthotopic liver transplantation in humans.


Autogenous polypropylene-supported collagen tubes for long-term arterial replacement.


An external velour surface for porous arterial prostheses.


Acceleration and human performance.

Acceleration and human performance.


Fundus examination with restricted spectrum light.


Biosynthesis in vitro of tryptophanase with polyribosomes from Escherichia coli.


The formation of nitrosamines by human intestinal bacteria.


Effect of glucagon on spheroplasts of Escherichia coli.


A study of macroanion inhibition of peptic activity using a micromethod.


Fertilization and the role of the acrosomal region in non-mammals.


Fluorescein angiography of the anterior segment. Its value in corneal disease.


Recurrence of proptosis caused by a second orbital tumour of different pathology.


Successful preservation of pig's liver for 5-8 hours by simple ice storage.


Complete prolapse of the rectum. A report on 140 cases treated by rectopexy.


A simple diagnostic computer and patient monitor.


Immune studies in malignant melanoma.

Immune studies in malignant melanoma.


Preoperative localization of parathyroid tumours.


The importance of blood-CO2 levels in head-injury management: improvement with hyperventilation.


Studies on the induction of transplantation tolerance at low zones of dosage.


Cell-mediated and humoral mechanisms in allograft and xenograft skin rejection.


Observations on the effect of horse anti-pig leucocyte serum in suppressing the rejection of renal allografts in pigs.


Specific inhibition of cardiac allograft rejection.


Indices of acute rejection after cardiac transplantation.


Horse anti-pig leucocyte serum prepared against stimulated lymphocytes: in vitro properties.


Modification of rejection in rat renal allografts across a strong histocompatibility barrier.


Cholecystokinin-pancreozymin (CCK): a physiological inhibitor of gastric secretion in man.


The secretion of pepsin 1 in peptic ulceration and its relationship to activity.


The evaluation and significance of vesico-ureteric reflux following renal transplantation.


The provision of a space for artificial lungs.


Haemodynamic aspects of auxiliary heterotopic liver transplantation in the pig.


The effect of ischaemia on the reticuloendothelial system of the canine liver.


Antigens and the leukocyte migration test in renal transplantation.


EEG synchronization, behavioral inhibition, and mesencephalic unit effects produced by stimulation of orbital cortex, basal forebrain and caudate nucleus.


A hospital study of the Providence group, with particular reference to subgrouping and the possible presence of R factors.


Congenital heart disease: clinical approach.


Diagnosis and management of abdominal trauma.


Pattern responses of low-frequency inferior colliculus neurons.


Recent contributions to the diagnosis of muscle disease.


Hertwig, Weismann, and the meaning of reduction division circa 1890.


Calcitonin and ultimobranchial glands in fishes.


Indiana State Medical Association and Women's Auxiliary. Roster of members.


The effects of ascorbic acid on bactericidal mechanisms of neutrophils.


Nuclear acidic proteins and cell proliferation.


Vitamin A deficiency in the germfree state.


Effect of rifampin and minocycline on meningococcal carrier rates.


Lymphocytic choriomeningitis virus: pathogenesis of acute central nervous system disease.


Antibacterial action of specific IgA and transport of IgM, IgA, and IgG from serum into the small intestine.


Cell function: its importance in chemical carcinogenesis.


Does antimicrobial therapy of streptococcal pharyngitis or pyoderma alter the risk of glomerulonephritis?


Chemoattractants of leukocytes, with special reference to lymphocytes.


Lymphadenopathy in secondary syphilis.

Lymphadenopathy in secondary syphilis.


From the gene to behavior.

From the gene to behavior.


Microbiological aspects of enterohepatic neutral sterol and bile acid metabolism.


Benis, benis, benis.

Benis, benis, benis.


Effect of 5-fluorouracil on skin-graft survival.


Successful renal transplantation in an infant with the hemolytic-uremic syndrone.


Absence of overresponding on a DRL schedule by hippocampally-lesioned rats.


A stereotaxic apparatus for the developing kitten brain.


A simple device to align vertically electrodes for stereotaxic implantation.


A stepper motor controlled microdrive for recording from unanesthetized animals.


The definitive plastic surgical treatment of the severe facial deformities of craniofacial dysostosis. Crouzon's and Apert's diseases.


Bertram D. Lewin, M.D. 1896-1971. A personal tribute.


Recent advances in the surgery of oesophageal atresia.


Desensitization: social and cognitive factors underlying the effectiveness of Wolpe's procedure.


Pharmacotherapy of children.

Pharmacotherapy of children.


Intestinal biopsy and coeliac disease.

Intestinal biopsy and coeliac disease.


Recent advances in the early detection and treatment of inborn errors with brain damage.


A modified Millipore technique for the study of oral leukocytes.


Preparation of human premolar roots for scanning electron microscopy.


Radiation and wound healing. Histological changes in the damaged skin of irradiated rats.


Sappington's anti-fever pills and the Westward migration.


The HL-A polymorphism.

The HL-A polymorphism.


Structure of membranes and role of lipids therein.


Lipid composition of vegetable oils.

Lipid composition of vegetable oils.


The cholestatic syndrome--1971.

The cholestatic syndrome--1971.


Histological observations on postincubation development of oviduct glands in Gallus domesticus. 3. Development of uterus.


Lung volume changes in asthma measured concurrently by two methods.


Pseudo-priming of Escherichia coli maltodextrin phosphorylase by 6 3 - -D-glucopyranosyl maltotriose.


Properties of DNA isolated from tissues of calves treated with S-(1,2-dichlorovinyl)-L-cysteine. II. Primer-template activity for bacterial DNA polymerases.


Aminoacyl-tRNA-Tu-GTP interaction with ribosomes.


Creutzfeldt-Jakob disease.

Creutzfeldt-Jakob disease.


Demonstration of missing membrane proteins in a colicin-tolerant mutant of E. coli K12.


Is RNase V a manifestation of RNase II?

Is RNase V a manifestation of RNase II?


Inability to detect RNase V in Escherichia coli and comparison of other ribonucleases before and after infection with coliphage T7.


Inhibition by thiopeptin of ribosomal functions associated with T and G factors.


Fusidic acid resistance of mitochondrial G factor from Neurospora crassa.


Evidence for mediated transport of glucose in mammalian pancreatic  -cells.


Cardiac transplantation today.

Cardiac transplantation today.


Effects of cortisol and antilymphocyte serum on lymphoid populations.


The essential role of corticosteroids in the induction of the immune response in vitro.


Production, chemistry and properties of bacterial pyrogens and endotoxins.


Currents in renal stone research.

Currents in renal stone research.


Complications of intrauterine transfusion.


An obscure affection of the hip joint.

An obscure affection of the hip joint.


A method for evaluating changes in sets of computer monitored physiological variables.


A comparison of methods for the automated diagnosis of thyroid dysfunction.


Recent advances in periodontology.

Recent advances in periodontology.


The significance of mother and child health in Ethiopia today: a review.


Structural investigations on the core polysaccharide of Escherichia coli 0100.


Replication of bacteriophage M13. Detachment of the parental DNA from the host membrane and transfer to progeny phages.


Proteolytic cleavage fo native DNA polymerase into two different catalytic fragments. Influence of assay condtions on the change of exonuclease activity and polymerase activity accompanying cleavage.


Continuous cultivation of microorganisms.


The specific inhibition of the expression of the lactose operon by D,L,-threo-phenylserine in Escherichia coli.


Vascular insufficiency of the intestines.


Diagnostic difficulties in a patient with jaundice and anaemia.


Factors influencing growth and differentiation of spleen colonies. II. Erythropoietin and actinomycin D.


Visual evidence of mitosis in splenic and peritoneal macrophages of the mouse and of the newt Molge vulgaris. Phase-contrast cine-micrographic investigations.


Inhibition of vitamin E absorption by a lipid fraction.


Improved assay of 4-hydroxybenzoic acid, biosynthetic precursor of coenzyme A.


Prof. Stefanini is Chairman of 18 Biennial Congress.


Effects of prolonged administration of porcine calcitonin in postmenopausal osteoporosis.


Positive fluorescent treponemal antibody test in systemic lupus erythematosus in childhood: report of a case.


Effect of medroxyprogesterone acetate on the sleep induced peak of growth hormone secretion.


A note on the use of Cannabis Sativa in the 17th century (Engelbert Kaempfer).


Controlled clinical trial of phenobarbital and-or light in reducing neonatal hyperbilirubinemia in a predominantly Negro population.


Salt in infant foods.

Salt in infant foods.


Behavioral development during recovery from nutritional marasmus.


Dietary cholesterol versus total body cholesterol.


Fish require dietary vitamin C.

Fish require dietary vitamin C.


Osteomyelitis causing postpartum sepsis. A case report.


George Otto Gey. (1899-1970). The HeLa cell and a reappraisal of its origin.


Sniffing and motivated behavior in the rat.


Stability and modification of consummatory behaviors elicited by electrical stimulation of the hypothalamus.


Cerebellar stimulation as a CS.

Cerebellar stimulation as a CS.


Crystallization and preliminary structural analysis of dihydrolipoyl transsuccinylase, the core of the 2-oxoglutarate dehydrogenase complex. Dihydrolipoyl transsuccinylase, one of the three enzymes comprising the Escherichia coli 2-oxoglutarate dehydrogenase (EC 1.2.4.2) complex, has been crystallized. Studies by x-ray diffraction and electron microscopy establish that the transsuccinylase has octahedral (432) symmetry, i.e., it consists of 24 subunits that are structurally identical.


Evidence for procollagen, a biosynthetic precursors of collagen. Incubation of rat calvaria for short times in the presence of a labeled amino acid revealed the existence of a collagen fraction (procollagen) that functions as a biosynthetic precursor of collagen. Procollagen contains an alpha1-like chain (pre-alpha1) that elutes earlier from CM-cellulose than does rat-bone alpha1 and has a molecular weight, estimated by acrylamide gel electrophoresis, of 120,000. A time-dependent conversion of pre-alpha1 to alpha1 was demonstrated by incubation of calvaria for periods varying from 9 to 60 min and by a pulse-chase experiment. Limited cleavage of procollagen with pepsin resulted in a molecule with a chain resembling alpha1 in chromatographic properties, molecular weight, and relative hydroxyproline and proline contents. Thus, conversion of procollagen to collagen is likely to occur in vivo by a proteolytic mechanism. The additional peptide sequences in procollagen may serve to initiate chain association in triple-helix formation, to facilitate molecular transport, and to inhibit intracellular fibrogenesis.


Heterogeneity, complexity, and repetition of the chloroplast DNA of Chlamydomonas reinhardtii. The chloroplast DNA of wild-type Chlamydomonas reinhardtii was isolated in a CsCl density gradient as a single, homogeneous density class with a mean density of 1.695 g/cm(3). Irrespective of sheared size, denatured chloroplast DNA renatured as a single homogeneous species. Compositional heterogeneity, presumably intramolecular, was revealed by the absorbance-temperature profile. The complement of unique nucleotide sequences of the chloroplast DNA, as determined by the rate of renaturation, was 1.94 x 10(8) daltons. This kinetic complexity is 26-fold less than the DNA content of a single gamete chloroplast, and 52-fold less than the chloroplast of a vegetative cell, which indicates that the chloroplast of C. reinhardtii possesses at least 26 copies of a unique nucleotide sequence.


Acetyl CoA carboxylase: the purified transcarboxylase component. Acetyl CoA carboxylase of Escherichia coli has been resolved into three functionally dissimilar proteins: (1) biotin-carboxyl carrier protein (BCCP); (2) a biotin carboxylase component that catalyzes the Mn-ATP-dependent carboxylation of BCCP to form CO(2) (-)-BCCP; and (3) a transcarboxylase component that catalyzes the transfer of the carboxyl group from CO(2) (-)-BCCP to acetyl CoA to form malonyl CoA.The transcarboxylase has been purified 1700-fold. Evidence that this protein catalyzes the transcarboxylase step includes the demonstration that it (a) catalyzes the carboxylation of BCCP, (b) catalyzes the BCCP-dependent exchange between [(14)C]acetyl CoA and malonyl CoA, (c) binds labeled acetyl CoA and malonyl CoA, and (d) catalyzes the decarboxylation of CO(2) (-)-BCCP. On the basis of this evidence, it is concluded that the transcarboxylase component contains sites for the acyl CoA group and for biotin, the covalently bound prosthetic group of BCCP.


In vitro synthesis of deoxynucleotide kinase programmed by bacteriophage "T4-RNA. RNA extracted from T4 phage-infected Escherichia coli cells can direct the synthesis of phage-specific deoxynucleotide kinase in a cell-free system from uninfected E. coli. The maximum messenger activity is obtained 8 min after infection at 37 degrees C and decreases there-after. The main activity of this messenger RNA has a sedimentation coefficient of about 15 S on a sucrose density gradient. The conditions necessary for the appearance of enzyme activity in vitro are the same as those required for de novo synthesis of protein. RNA from cells infected with a T4 amber mutant incapable of inducing the kinase in vivo lacks the ability to direct the synthesis of enzyme in vitro.


Stimulation of human leukocyte thromboplastic activity by endotoxin.


The metastatic behavior of a spleen-tropic reticulum cell sarcoma in splenectomized mice.


Role of the thymus in the recovery of hemolytic plaque formation after x-irradiation.


Two antigenically different types of macrophages.


Dissociation of erythropoietin from erythropoietin-antierythropoietin complex.


Inhibition of human plasma deoxyribonuclease I by ribonucleic acid.


Two-dimensional separation of embryonic and adult colony forming units. A study of differentiation in hemopoiesis.


The mycobacterial cell wall.

The mycobacterial cell wall.


Bactericidal antibodies to Hemophilus influenzae.


The ecdysones.

The ecdysones.


Population growth and economic welfare.

Population growth and economic welfare.


Post-prandial ionic and water exchange in the rumen.


Sucrose.

Sucrose.


Rat-bite fever.

Rat-bite fever.


Genetical studies on active transport.

Genetical studies on active transport.


Perfusion scanning in chronic obstructive lung disease.


The role of lung scanning in pulmonary embolism.


Superinfection exclusion by P22 prophage in lysogens of Salmonella typhimurium. 1. Exclusion of generalized transducing particles.


Superinfection exclusion by P22 prophage in lysogens of Salmonella typhimurium. II. Genetic evidence for two exclusion systems.


Identification of the acrylamide gel protein peak for gene C of phages S13 and phy X174.


Phi X gene expression in UV-irradiated cells treated with chloramphenicol.


A new generalized transducing phage for Salmonella typhimurium LT2.


Delayed lysis in Salmonella phage P22: the continued division of mutant-infected cells actively producing phaage.


Lysogenization by bacteriophage lambda and the regulation of lambda repressor synthesis.


George Augustus Ketchum--teacher-administrator-physician.


The J. Burns Amberson LECTURE  The induction and expression of cell-mediated hypersensitivity in the lung.


Tuberculosis in canine and feline populations. Study of high risk populations in Pennsylvania, 1966-1968.


Reverse dermis graft: a versatile technic.


Tuberculosis in canine and feline populations. Review of the literature.


Splenic cyst: a case report and review of literature.


Bactericidal effect of the air-fluidized bed.


Thymus, immunity and autoimmunity.

Thymus, immunity and autoimmunity.


Circular DNA.

Circular DNA.


Proteins of the nervous system.

Proteins of the nervous system.


Antibody diversity.

Antibody diversity.


Skin arthroplasty of the elbow.

Skin arthroplasty of the elbow.


A study of the epizootiology and control of Salmonella typhimurium infection in a commercial poultry organisation.


Hyperfunction of the adrenal cortex: a review.


Historical records of the veterinary profession in Australia. 3. Animal health and associated legislation in New South Wales, from the foundation of the colony until 1900. 2. The Bruce era.


Absence of complete repression of a specific part of the DNA during in vitro transcription of yeast deoxyribonucleoprotein.


Transcription: role in the initiation and replication of DNA synthesis in Escherichia coli and phiX174.


The inhibition of RNA synthesis by histones.


A 44-S particle derived from the 50-S ribosomal subunit of Escherichia coli and its polymerization.


Effects of bromine on the template and messenger specificities of polynucleotides.


Bilirubin metabolism in the newborn.

Bilirubin metabolism in the newborn.


Juvenile dermatitis herpetiformis in the light of immunofluorescence studies.


Can pemphigus be provoked by a burn?

Can pemphigus be provoked by a burn?


Aeriological factors in squamous cell skin cancer.


Immunofluorescent serological studies in vasculitis superficialis "Ruiter".


Alienation, anomie and delinquency.

Alienation, anomie and delinquency.


John Lloyd Burns 1916-1971.

John Lloyd Burns 1916-1971.


Procarbazine as an immunosuppressive agent in the corneal xenograft reaction.


Primary reticulum cell sarcoma of bone. Significance of clinical features upon the prognosis.


Experience with 1-phenylalanine mustard dihydrochloride in isolation-perfusion of extremities for malignant melanoma.


Cisterns of posterior fossa.

Cisterns of posterior fossa.


Intrathecal radioisotopes for the treatment of brain tumors.


Subdural hematomas of infancy.

Subdural hematomas of infancy.


Myelocele: rupture of the neural tube?

Myelocele: rupture of the neural tube?


The barriers of the central nervous system.


W. James Gardner: a biographical sketch.


Galactose metabolism of the red cell.

Galactose metabolism of the red cell.


Effect of time, temperature, and peptic activity on intrinsic factor content of acid gastric juice.


Mechanism of the antipeptic action of amylopectin sulfate (SN-263), and antiulcer, mucin-like agent.


Primary reticulosis of the central nervous system.


Psychotomimetic phenethylamines.

Psychotomimetic phenethylamines.


Automated system for analytical microbiology. I. Theory and design considerations.


Transfer of training in articulation therapy.


Evaluation of special hearing aids for deaf children.


A new technique for separation of coverglass substrate from epoxy-embedded specimens for electron microscopy.


Improved orientation of plant tissues for thin sectioning.


Automated system for analytical microbiology. II. Construction of system and evaluation of antibiotics and vitamins.


Current status: the management and treatment of poisoning. General principles of treatment and specific antidotes.


Treatment of organophosphorus and chlorinated hydrocarbon insecticide intoxications.


Treatment of caustic alkali poisoning.

Treatment of caustic alkali poisoning.


Radiographic and radioisotopic methods of evaluation of the kidneys and urinary tract.


The "E.M.G." syndrome (Exomphalos, Macroglossia, Gigantism).


Postoperative complications following operation for oesophageal atresia and tracheo-oesophageal fistula.


Optimization of resolution in scintigraphy.


Blood groups and their secretion in rheumatic fever.


Cold auto-agglutinins.

Cold auto-agglutinins.


"Sternzellen" in the liver: perisinusoidal cells with special reference to storage of vitamin A.


The menstrual cycle: a double-blind study of symptoms, mood and behavior, and biochemical variables using enovid and placebo.


"All of none" antibacterial disk tests in synthetic medium.


In memorian. William C. Manion, M.D.

In memorian. William C. Manion, M.D.


A rapid embedding technic for the preparation of undecalcified bone and tooth sections.


Sensory deprivation on visceral activity. 3. The effect of olfactory deprivation of canine gastric secretion.


Ubiquinone biosynthesis in Escherichia coli K-12. Accumulation of an octaprenol, farnesylfarnesylgeraniol, by a multiple aromatic auxotroph. Cell extracts of a multiple aromatic auxotroph of Escherichia coli K-12, strain AB2830, grown in the absence of precursors of the quinone rings of the ubiquinone and menaquinone molecules, converted 4-hydroxy[U-(14)C]benzoate into a mixture of 3-octaprenyl-4-hydroxybenzoate and 2-octaprenylphenol. An octaprenol, farnesylfarnesylgeraniol, was isolated from such cell extracts and characterized by n.m.r. and mass spectroscopy. Neither the octaprenol, nor polyprenylation of 4-hydroxy[U-(14)C]benzoate, could be detected in cell extracts of strain AB2830 grown in the presence of 0.1mm-4-hydroxybenzoate. It was concluded that, in the biosynthesis of ubiquinone, the polyprenyl side chain is added to 4-hydroxybenzoate as a C(40) unit, the active form of which is converted by cell extracts into farnesylfarnesylgeraniol. The multiple aromatic auxotroph, when grown in the absence of 4-hydroxybenzoate but in the presence of 4-aminobenzoate, converted the latter compound into 3-octaprenyl-4-aminobenzoate. This compound was isolated from whole cells and characterized by n.m.r. and mass spectroscopy.


Biosynthesis in vitro of tryptophanase by polyribosomes from induced cultures of Escherichia coli. 1. Polyribosomes were isolated from Escherichia coli grown in media in which tryptophanase is induced and in which it is repressed. The polyribosomes from the induced bacteria had a small amount of tryptophanase activity associated with them. 2. A portion of the enzyme activity remained bound to polyribosomes during centrifuging in sucrose gradients. 3. Incubation of tryptophanase-containing polyribosomes with puromycin released enzyme activity. 4. The binding of the enzyme to the polyribosomes did not depend on the presence of DNA. 5. When the polyribosomes were incubated under conditions of protein synthesis with supernatant fraction obtained from repressed bacteria, a small but statistically significant increase in enzyme activity was produced. 6. When a radioactive amino acid was included in the incubation mixture for the tryptophanase system a radioactive protein was obtained whose chromatographic, electrophoretic and sedimentation properties were identical with those of tryptophanase. 7. The amount of incorporation was consistent with the amount of new enzyme synthesis predicted by the increase in enzyme activity. Both radioactive incorporation and increase in enzyme activity were shown to be energy-dependent and also negative controls were obtained by using zero-time incubations or polyribosomes isolated from either repressed cells or a mutant lacking the ability to produce tryptophanase. 8. The distribution of radioactive leucine in the carboxyl region of the newly labelled tryptophanase was examined by digesting the labelled protein with carboxypeptidases. It was shown that the radioactivity was more highly concentrated towards the carboxyl terminus when the incubation times for protein synthesis were shorter (implying that, with longer incubation times, longer lengths of polypeptide chain contained radioactive amino acid residues).


Effect of cyclophosphamide on the murine hematopoietic stem cell compartment as measured by different assay techniques.


Response of the preosteoblast and stem cell of rat bone marrow to a lethal dose of x-irradiation or cyclophosphamide.


Hemoglobin Köln disease occurring as a fresh mutation: erythrocyte metabolism and survival.


Osler's museum specimens of heart disease. Their nature and significance.


Sick sinus node syndrome as the presenting manifestation of reticulum cell sarcoma.


The Kuna Indians: their attitudes toward the aged.


Gene expression in vitro from deoxyribonucleic acid of bacteriophage T7.


Arginine decarboxylase from Escherichia coli. IV. Structure of the pyridoxal phosphate binding site.


Studies on the conversion of proinsulin to insulin. I. Conversion in vitro with trypsin and carboxypeptidase B.


Deoxyribonucleic acid polymerase of bacteriophage T7.


The purification and characterization of Escherichia coli enolase.


Protein degradation in Escherichia coli. II. Strain differences in the degradation of protein and nucleic acid resulting from starvation.


Biosynthesis of riboflavin. Formation of 6-hydroxy-2,4,5-triaminopyrimidine in rib 7  mutants of Saccharomyces cerevisiae.


Sugar transport. 3. Purification and properties of a phosphocarrier protein (HPr) of the phosphoenolpyruvate-dependent phosphotransferase system of Escherichia coli.


Pharmacologic evaluation of gentamicin in newborn infants.


Gentamicin in serious neonatal infections: absorption, excretion, and clinical results in 25 cases.


Gentamicin in the treatment of meningitis.


Gentamicin in pediatrics. II. Treatment of severe urinary-tract infections caused by gram-negative bacilli and of staphylococcal infections.


Susceptibility of gram-negative anaerobic bacilli to gentamicin and other aminoglycosides.


R factor-mediated resistance to gentamicin in a clinical isolate of Escherichia coli.


Peritoneal clearance and removal of gentamicin.


The use of gentamicin in peritoneal dialysis. II. Microbiologic and clinical results.


Chelsea Hospital for Women, 1871-1971.

Chelsea Hospital for Women, 1871-1971.


Cardiac transplant as left-ventricular assist device. I. Technique.


Lung function at birth in babies developing respiratory distress.


Sex chromosome abnormalities and the gynaecologist.


Educational programs in practical-vocational nursing accredited by NAPNES.


Sir Aldo Castellani, K.C.M.G., M.D., F.R.C.P., F.A.C.P.


Antimalarial effects of tetracyclines in man.


Treatment of Plasmodium falciparum malaria in Cameroon with a single dose of antifolic drugs. 2. Combination of sulfametopyrazine and trimethoprim.


Treatment of Plasmodium falciparum malaria in Cameroon with a single dose of antifolic drugs. 1. Combination of sulfametopyrazine and pyrimethamine.


Episodic pain in the thigh.

Episodic pain in the thigh.


Van Gogh's suicide.

Van Gogh's suicide.


Diseases of domestic rabbits: a bibliography.


A small-animal operating table for use with halothane anaesthetic administered by intubation or inhalation.


A simple apparatus for the inflation fixation of lungs at constant pressure.


Polyribosomes of Escherichia coli. I. Isolation of polysomes from a complex of DNA and membrane.


Polyribosomes of Escherichia coli. II. In vivo and in vitro studies on DNA bound and cytoplasmic polysomes.


Purification and characterization of 50S ribosomal proteins of Escherichia coli.


Conversion of lambda defective lysogens from the non-immune state to the immune state.


Segregation of galactoside permease, a membrane marker during growth and cell division in Escherichia coli.


Social antivenereal activity of the Polish Eugenic Society in Warsaw (1916-1939). A contribution to the history of medical societies.


Selforganization of matter and the evolution of biological macromolecules.


The effect of partial amygdalectomy on emotional disturbances and epileptic seizures.


Contraceptive technology: current and prospective methods.


On fitting the 'facts' of social class and criminal behaviour: a rejoinder to Box and Ford.


The morphology and development of neuroglial cells.


The interaction of axonal and dendritic elements in the developing and the mature synapses.


Developmental aspects of synaptology with special emphasis upon the cerebellar cortex.


The biological activities of the subunits of the 7S nerve growth factor protein.


Studies on the development of the avian visual system.


The thyroid as a time clock in the developing nervous system.


Hormonal and nutritional aspects of prenatal brain development.


The effect of visual deprivation on the developing avian optic lobe.


Developmental alterations in cerebral ribonucleic acid and protein synthesis.


Regulatory mechanisms responsible for alterations in protein and nucleic acid synthesis in developing brain tissue.


Levels of two brain-specific proteins during degeneration and development.


S-100 protein accumulation in developing animals and cell cultures.


Differentiation of the neural elements of the cerebral cortex in the rat.


In vitro steroid synthesis by foetal rabbit adrenals.


Effects of zinc and other metal ions on the stability and activity of Escherichia coli alkaline phosphatase. Measurement of the ultraviolet circular dichroism of apo-(alkaline phosphatase) in urea solutions showed substantial denaturation in 3m-urea. A zinc-deficient mutant alkaline phosphatase behaved similarly. The stability of the enzyme in 6m-urea was followed as a function of its zinc content and was found to be dependent on the first two of the four zinc atoms bound by apoenzyme. Phosphatase activity was mostly dependent on a second pair of zinc atoms. Mn(2+), Co(2+), Cu(2+) or Cd(2+) also restored structural stability. Sedimentation-velocity and -equilibrium experiments revealed that dissociation of the dimer accompanied apoenzyme denaturation in urea concentrations of 1m or higher, without treatment with disulphide-reducing agent.


Ubiquinones, plastoquinones and vitamins K.


Characterization of cytoplasmic and chloroplast 5S ribosomal ribonucleic acid from broad-bean leaves. Green leaves of the broad bean (Vicia faba) contain two 5S RNA components that can be separated from each other by polyacrylamide-gel electrophoresis. The major component is located in the larger subunit of cytoplasmic ribosomes, whereas the minor component occurs in the larger subunit of chloroplast ribosomes. Their electrophoretic mobilities relative to those of Escherichia coli 5S RNA (120 nucleotides) and plant 4S RNA (78 nucleotides) suggest that they consist of 118 and 122 nucleotide residues respectively. Thermal ;melting' profiles of plant cytoplasmic and chloroplast 5S RNA species at 260nm indicate the similarity of their secondary structures, not only to each other, but also to those of E. coli and mammalian 5S RNA species. The base compositions of the two plant 5S RNA species have more in common with each other than with the corresponding molecules from either E. coli or mammalian cells.


Remarks of moderator.

Remarks of moderator.


Genetic counseling: the trees and the forests.


The pathogenesis of diabetic angiopathy and growth hormone.


Effect of anesthetic drugs on the heart: a critical review of myocardial contractility and its relationship to hemodynamics.


Clinical trial of 'furoxone' in children with enteric fever.


Cardiac arrhythmias related to artificial pacemakers.


The interaction in vitro between polymorphonuclear leukocytes and mycoplasma. The interaction, between mycoplasma (PPLO) and human or rabbit leukocytes was examined in vitro. Upon incubation of M. hominis or M. arthritidis for 2 hr with rabbit peritoneal exudate granulocytes or leukocytes from human peripheral blood, no killing of mycoplasma was observed either in the presence or absence of type-specific antiserum. However, (14)CO(2) production from glucose-1-(14)C was stimulated up to 10-fold in the presence of live or heat-killed PPLO. The extent of stimulation depended upon the number of organisms and the presence of type-specific antiserum. The stimulation of (14)CO(2) production seems not because of tight adherence of PPLO to the leukocytes, since PPLO were quantitatively recovered in the medium after sedimenting the granulocytes. The enhanced conversion of medium lysolecithin to cellular lecithin that accompanies phagocytosis of polystyrene particles was significantly reduced when PPLO were also present. Mycoplasma alone elicited no stimulation of lecithin formation. Killing of E. coli, a microorganism readily engulfed and killed by leukocytes in vitro, was diminished when the leukocytes were preincubated with mycoplasma. These findings indicate that M. hominis and M. arthritidis are not ingested by granulocytes to any detectable extent, but that these organisms affect the leukocytes' metabolism and also impair phagocytosis of E. coli.


Peculiar immunobiology of bone marrow allografts. II. Rejection of parental grafts by resistant F 1  hybrid mice. F(1) hybrid mice are capable of rejecting inbred parental strain bone marrow grafts after a single lethal exposure to X-rays. The incompatibility is genetically controlled by the Hybrid-histocompatibility-1 (Hh-1) locus in or near the D end of the Histocompatibility-2 (H-2) region. The onset of parental graft rejection begins 9-12 hr after transplantation and is completed by 24 hr. Maturation of hybrid resistance does not occur until the 22nd day of life. In adults, the resistance to parental marrow grafts can be temporarily abrogated or weakened by administration of cyclophosphamide or dead cultures of Corynebacterium parvum, acute supralethal exposures to radiation, or by split-dose irradiation with 6-37-day intervals. Parental marrow grafts elicit a transplantation reaction in irradiated F(1) mice which is indistinguishable from that elicited in irradiated allogeneic (H-2-incompatible) hosts. Because of this immunogenetic similarity, the following question is raised: are the same or different alloantigens responsible for rejection of parental and allogeneic marrow grafts? In the first case, Hh-1 alleles would be recessive determinants of tissue-specific transplantation antigens, whereas in the second case they would be the determinants of parental- and tissue-specific antigens subject to genetic suppression in Hh-1 heterozygotes. Although the available evidence is not conclusive in excluding one of the two possibilities, it favors the concept that allograft reactivity to hemopoietic cells is elicited by recessive tissue-specific antigens.


The conquest of scurvy and the discovery of Hawaii: an ethnobotanical triumph.


Cholesterol metabolism in the macrophage. II. Alteration of subcellular exchangeable cholesterol compartments and exchange in other cell types. Macrophage membrane cholesterol is present in two subcellular cholesterol pools, a rapidly exchanging compartment comprising about two-thirds of the total cholesterol, and a slowly exchanging compartment comprising one-third of the total. The morphological identification of the kinetically distinguishable pools proceeded by alteration of each compartment. Trypsin treatment markedly decreased the rate of cholesterol exchange without removing cholesterol from the membrane. Recovery of normal exchange rates took more than 7 hr and required protein synthesis. This suggested that a plasma membrane receptor is involved in positioning of lipoproteins for exchange, and is consistent with the plasma membrane localization of the rapidly exchanging compartment. Extensive pinocytosis by nondegradable dextran, dextran sulfate, or sucrose resulted in the accumulation of many secondary lysosomes, thus increasing the relative proportion of intracellular membranes. The measurable granule membrane area, cholesterol content, phospholipid content, and the relative size of the slowly exchanging cholesterol compartment all increased. The amount of intracellular membrane altered by extensive phagocytosis of latex particles also increased the size of the slowly exchanging cholesterol compartment. This suggested that the slowly exchanging pool of cholesterol represented the intracellular membranes primarily of lysosomal origin. Rabbit alveolar macrophages and thioglycollate-stimulated peritoneal macrophages contain many secondary lysosomes as a result of multiple bouts of in vivo phagocytosis and pinocytosis. In both of these cells the fast and slow pools are equal in size. The increased cholesterol content was attributable to the increase in the relative size of the slowly exchanging compartment. L-cells and melanoma cells also exchange their cholesterol with that of serum lipoproteins. Both cells contain few cholesterol-rich intracellular membranes, and had lower cellular cholesterol contents. In these cells the slowly exchanging pool was a minor contribution to cell cholesterol. Studies with these cells provided further evidence for the lysosomal membrane and plasma membrane localization of the slowly and rapidly exchanging cholesterol compartments.


Clinical trial of a pepsin inactivator in the treatment of peptic ulcer. A preliminary report.


The effectiveness of iontophoresis in reducing cervical hypersensitivity.


Implant-bone macerator.

Implant-bone macerator.


Experimental human gingivitis.

Experimental human gingivitis.


Skin grafting the burned patient. Essentials of nursing care.


Edward Mather Kent (1907-1970).

Edward Mather Kent (1907-1970).


The metabolism and pharmacology of 5-fluorouracil.


Cameron Haight (1901-1970).

Cameron Haight (1901-1970).


List of members of The American Association for Thoracic Surgery, 1971-1972.


Clinico-pathologic correlations in acute poststreptococcal glomerulonephritis. A correlation between renal functions, morphologic damage and clinical course of 46 children with acute poststreptococcal glomerulonephritis.


Control of hydrogen ion homeostasis and renal acidosis.


Education for nursing--the diploma way.

Education for nursing--the diploma way.


Electronic data processing in pediatric EEG research.


Coping and marathon sensitivity training.


Dogmatism and sociometric status as determinants of interaction in a small group.


The use of granular pesticides from the point of view of residues.


Recent applications of mass spectrometry and combined gas chromatography-mass spectrometry to pesticide residue analysis.


The use of human sclera as an encircling band for surgical treatment of retinal detachment.


Management of keloids by surgical excision and local injections of a steroid.


Surgical advances in the treatment of rare craniofacial anomalies.


Altered plasma membranes in experimental scrapie.


Evaluation of a new selective beta-adrenergic receptor stimulant.


Direct microscopic studies of clamp connection formation in growing hyphae of Schizophyllum commune. II. The A-mutant homokaryon and pseudo-clamp connections.


Human arm to retina circulation time. Determination by simultaneous fluorophotometry.


The purification and properties of the  -lactamase specified by the resistance factor R-1818 in Escherichia coli and Proteus mirabilis. 1. The beta-lactamase specified by the R-1818 resistance factor in Escherichia coli was purified 300-fold; the resulting preparation gave a single peak on Sephadex G-100 and a single band on polyacrylamide-gel electrophoresis. 2. The beta-lactamase specified by the same R-factor in Proteus mirabilis was purified over 2000-fold, but was still far from pure. The specific activity of this preparation was one-fifth that of the purified enzyme from E. coli. 3. The two enzymes were shown to be identical as regards substrate specificity, pH optimum, K(m) values and molecular weight. 4. It is suggested that the low beta-lactamase activity of extracts of P. mirabilis (R-1818), about 5% of that from E. coli (R-1818) in crude extracts, could be due to inefficient transcription of the R-factor DNA by Proteus RNA polymerase.


Low-density lipoproteins.

Low-density lipoproteins.


Characterization of the  -lactamase specified by the resistance factor R-1818 in E. coli K12 and other Gram-negative bacteria. 1. The amino acid composition of the beta-lactamase from E. coli (R-1818) was determined. 2. The R-1818 beta-lactamase is inhibited by formaldehyde, hydroxylamine, sodium azide, iodoacetamide, iodine and sodium chloride. 3. The K(m) values for benzylpenicillin, ampicillin and oxacillin have been determined by using the R-factor enzyme from different host species. The same values were obtained, irrespective of the host bacterium. 4. The molecular weight of the enzyme was found to be 44600, and was the same for all host species. 5. The relationship of R-1818 and R-GN238 beta-lactamases is discussed.


Some relationships between R-factor and chromosomal  -lactamase in Gram-negative bacteria. 1. The beta-lactamases specified by Klebsiella aerogenes 418 and the R-factor R-7268 have been partially purified. 2. The molecular weights of the K. aerogenes strains 418 and 373, Aerobacter cloacae 53, R-7268 and R-TEM beta-lactamases were all about 20000; that of the enzymes from Escherichia coli strains 419 and 214T was about 31000. 3. These enzymes were also compared by means of their K(m) values for benzylpenicillin and ampicillin, and their behaviour on starch-gel electrophoresis. 4. The beta-lactamases specified by the two Klebsiella strains, the Aerobacter strain, and the R-factors R-TEM and R-7268 were found to comprise a broadly similar group. However, within this group, only two enzymes seemed to be identical, namely those specified by the two R-factors. The two E. coli strains produce identical beta-lactamases which are very different from the ;Klebsiella/Aerobacter-type' enzymes.


Effect of point mutations in the lac promoter on transient and severe catabolite repression of the lac operon of Escherichia coli. 1. Experiments were devised to show whether the point mutations L8 and L29 in the lac promoter alleviate transient repression. 2. Several recombinants were picked from matings between a single F(-)p(+) strain and Hfr strains carrying mutations L8 and L29. All of the 19 p(-) recombinants tested proved to suffer no transient repression, whereas all of the eight p(+) recombinants tested suffered prolonged transient repression. 3. A diploid strain was constructed in which more than 90% of the thiogalactoside transacetylase is synthesized from the episome with a wild-type lac promoter, whereas 100% of the beta-galactosidase is synthesized from the chromosome with a promoter carrying mutation L8. In this diploid the synthesis of thiogalactoside transacetylase suffered transient repression but the synthesis of beta-galactosidase did not. 4. Exactly similar results were obtained with a diploid strain in which the chromosomal promoter carried mutation L29. 5. The same diploid strains were used in experiments to show whether mutations L8 and L29 alleviate the severe catabolite repression caused by growth in glucose plus gluconate. In both strains glucose+gluconate repressed the synthesis of beta-galactosidase much less than the synthesis of thiogalactoside transacetylase. 6. These and previously reported results can be explained by assuming (a) that both mutations L8 and L29 render the lac promoter partially, but not completely, insensitive to catabolite repression, and (b) that transient repression is an exceptionally severe form of catabolite repression.


The limitation of glycolysis in adenine-deficient Escherichia coli. 1. In many instances, there was no change in the rate of oxygen consumption per cell when adenine was withdrawn from purine auxotrophs of Escherichia coli and Salmonella typhimurium. 2. However, adenine deficiency inhibited the metabolism of glucose, mannitol or glycerol in a purA(-) strain, in purB(-) or purH(-) strains in the absence of histidine and in purB(-) mutants supplied with hypoxanthine. These are all instances where reactions occur to consume adenine nucleotides. 3. The inhibition of glucose oxidation is accompanied by the accumulation of fructose 1,6-diphosphate and dihydroxyacetone phosphate. 4. Insufficiency of ADP for phosphoglycerate kinase is the most probable cause of the inhibition.


The separation of intracellular serum albumin from rat liver. 1. Antibody precipitation of serum albumin from rat liver extracts yields impure preparations of the protein. 2. When rat liver is labelled with l-[1-(14)C]leucine, antibody precipitation of albumin leads to material that is contaminated with a protein or proteins of very high specific radioactivity. Only 10-25% of the radioactivity of the antibody precipitate is associated with serum albumin. 3. A chromatographic procedure is described that can be used to separate radiochemically pure serum albumin from antibody precipitates obtained from extracts of rat liver. 4. Extracellular albumin secreted by liver slices yields a precipitate with antibody which contains much less radioactive impurity. About 70-90% of the radioactivity is associated with serum albumin. Serum albumin separated by antibody precipitation from rat serum labelled in vivo was not contaminated with the radiochemical impurities associated with intracellular albumin. 5. A simple method is described of obtaining the content of serum albumin in rat liver extracts by the technique of isotope dilution and ion-exchange chromatography.


Chromatography of nucleic acid digests on thin layers of cellulose impregnated with polyethyleneimine. Methods are described for the separation of oligodeoxyribonucleotides and oligoribonucleotides by chromatography on thin layers of cellulose impregnated with polyethyleneimine.


Phototransformation of 4-thiouridine in Escherichia coli valine transfer ribonucleic acid to uridine, cytidine, and N 4 -methylcytidine.


Sulfur-deficient transfer ribonucleic acid. The natural substrate for ribonucleic acid sulfurtransferase from Escherichia coli.


Template activities of the phi X-174 replicative allomorphic deoxyribonucleic acids.


Pyrimidine dimer formation in poly (d-dT) and apurinic acid.


Binding of radioactive oligonucleotides to ribosomes.


Alkylated DNA as template in the synthesis of RNA in vitro.


Characterization of ribosomes and RNAs from Mycoplasma hominis.


Ribosomes from fig fruits: physical properties and the occurrence of transient dimers.


Reaction of puromycin with N-acetylphenylalanyl-tRNA on ribosomes reassociated from Escherichia coli ribosomal subunits.


The activity of ribosomes whose RNA has been degraded by incubation in the presence or absence of oxidized glutathione.


Effect of age and arteriosclerosis on the response of Parkinsonian patients to levodopa. Twenty-four patients with Parkinsonism were treated with levodopa for up to one year. Ten were aged under 65, 12 were aged 65 or over, and two were specifically included because they were considered to have arteriosclerotic Parkinsonism. These two patients showed no response to treatment. The 10 younger patients showed less clinical evidence of arteriosclerosis than the older ones, and responded significantly better to treatment with levodopa. Mean improvement was 61% in the younger group after 12 months' treatment and 28% in the older group. Improvement was greatest within three months of starting treatment. Abnormal movements which resulted from treatment with levodopa could be reduced with only slight loss of therapeutic benefit by the addition of tetrabenazine.


The role of bone marrow of x-irradiated mice in thymic recovery.


Colony formation in agar: in vitro assay for haemopoietic stem cells.


Short-term cultures of mouse marrow cells separated by velocity sedimentation.


Immunological unresponsiveness against the 4-hydroxy-3,5-dinitro-phenacetyl (NNP) hapten in different lymphoid cell populations.


Genetics of the immune response. I. The immune response to the phage fd in high and low responding inbred strains of mice.


The problem of poverty: a historical and psychological view.


Inhibition of growth of Candida albicans by iron-unsaturated lactoferrin: relation to host-defense mechanisms in chronic mucocutaneous candidiasis.


Suppressed synthesis of viral DNA, protein, and mature virions during replication of canine herpesvirus at elevated temperature.


4,17 -dimethyl-4-aza-5 -androstan-17 -ol acetate and related azasteroids.


Antihypertensive properties of cryptenamine used with reserpine and methyclothiazide.


Derivatives of 17 -aza-D-homo-5-androsten-3 -ol.


The Department of Medicine University of Otago Medical School, Dunedin, New Zealand.


The mammary gland of the ewe as a source of neutrophils and macrophages for repeated collections.


Bitter humour: the development of ideas about bile salts.


Radioisotope ventricular dilution curves and standard radiocardiography in mitral valve disease.


The Chester Scott Keefer auditorium.

The Chester Scott Keefer auditorium.


Cellular development of the human fetus and maternal poverty.


Mechanisms of hemolysis--the minimal red-cell defect.


Soy protein quality.

Soy protein quality.


Anemia and iron intake.

Anemia and iron intake.


Regulation of growth hormone secretion by growth hormone.


Mobilization of liver iron by ferroxidase. I. (Ceruloplasmin).


Zinc homeostasis during pregnancy.

Zinc homeostasis during pregnancy.


Fatty acid esterification in rat adipose tissue from various body sites.


Parathyroid hormone effects on mineral absorption and excretion.


Trigonelline as a major urinary metabolite of niacytin in the rat.


Copying errors by children as a function of stimulus size and mode of presentation.


Form perception: dimensions of pattern reproduction.


Effects of a creativity training program on stimulus preferences.


Need associations to acquisition modes, education, and adjustment.


Labeling theory and community psychiatry. The impact of psychiatric sociology on ideology and practice in American psychiatry.


The active centre of rabbit muscle triose phosphate isomerase. The site that is labelled by glycidol phosphate. 1. Glycidol (2,3-epoxypropanol) phosphate is a specific irreversible inhibitor of rabbit muscle triose phosphate isomerase (EC 5.3.1.1); the site of attachment has now been studied. 2. The labelled enzyme was digested with pepsin and a modified peptide isolated. The sequence of the peptide is: Ala-Tyr-Glu-Pro-Val-Trp. 3. It is the glutamic acid residue in this peptide that is labelled: the peptide is thus a gamma-glutamyl ester derived from glycerol phosphoric acid. The same site is labelled by a mixture of glycidol and inorganic phosphate. 4. Kinetic and stereochemical features of these reactions are discussed.


Studies on the high-sulphur proteins of reduced merino wool. Amino acid sequence of protein SCMKB-3B 3 . The complete amino acid sequence of wool protein SCMKB-IIIB3 was determined. The peptides used for the sequence work were obtained by peptic and thermolysin digestions and were fractionated by chromatography on DEAE-cellulose, paper chromatography and electrophoresis. The peptides were analysed by dansyl-Edman degradation, mass spectrometry and tritium-labelling of C-terminal residues. The protein consists of 98 residues and has acetylalanine as N-terminal residue and carboxymethylcysteine as C-terminus. It is homologous with protein SCMKB-IIIB2 (Haylett & Swart, 1969). A salient feature of the sequence of protein SCMKB-IIIB3 is three consecutive cysteine residues.


Studies on the high-sulphur proteins of reduced merino wool. Amino acid sequence of protein SCMKB-3B 4 . The complete amino acid sequence of protein SCMKB-IIIB4 is presented. It is closely related to the sequence of protein SCMKB-IIIB3 (Haylett, Swart & Parris, 1971) differing in only four positions. The peptic and thermolysin peptides of protein SCMKB-IIIB4 were analysed by the dansyl-Edman method (Gray, 1967) and by tritium-labelling of C-terminal residues (Matsuo, Fujimoto & Tatsuno, 1966). This protein is the third member of a group of high-sulphur wool proteins with molecular weight of about 11400. It consists of 98 residues and has acetylalanine and carboxymethylcysteine as N- and C-terminal residues respectively.


The utilization of prolyl peptides by Escherichia coli. Peptides that have an N-terminal proline residue are taken up by Escherichia coli and are degraded by intracellular peptidases. A mutant that is unable to transport oligopeptides with N-terminal alpha-amino acids is also unable to transport the peptides with N-terminal proline. Dipeptides and oligopeptides can prevent the uptake of the corresponding prolyl peptides and the converse competitive interactions are also observed. Although the peptide alpha-amino group is essential to the process of peptide transport, the results with the prolyl peptides indicate that the dipeptide and oligopeptide permeases can handle peptides with either an alpha-amino or alpha-imino group.


The requirement for the protonated  -amino group for the transport of peptides in Escherichia coli. Many glycine peptides support growth of a glycine auxotroph of Escherichia coli. If the alpha-amino group of these peptides is methylated, the products are still utilized for growth, and also retain comparable ability with the unsubstituted peptides to compete with natural peptides for transport into the cell. In contrast, glycine peptides devoid of an alpha-amino group, or that have the alpha-amino group substituted by one of a number of acyl groups are not utilized, although E. coli possesses intracellular enzymic activity able to release glycine from such compounds; further, these derivatives do not compete with natural peptides for transport into the cell.


Uptake of tetracycline by membrane preparations from Escherichia coli. 1. A membrane fraction from Escherichia coli has been prepared essentially free from ribosomes by treatment of the membranes with Triton X-100 at 0 degrees C followed by differential centrifugation. 2. The ribosome-free membrane vesicles absorbed tetracycline by a reversible temperature-dependent process with an apparent K(m) of 0.029mm at pH7.5 and 37 degrees C. 3. The absorption process was negligible below 25 degrees C and had an optimum at 40 degrees C; a pH optimum at 7.5 was observed. 4. The absorption of tetracycline was strongly inhibited by EDTA and ATP; ADP inhibited less strongly and AMP had no effect. 5. There was no significant difference in the rates or extent of uptake of tetracycline by membranes prepared from tetracycline-sensitive and tetracycline-resistant, R-factor-bearing E. coli.


Intensification by intrauterine devices of bactericidal activity in the rabbit uterus.


Current concepts of the morphology and biology of Treponema pallidum based on electron microscopy.


Bilirubin in the amniotic fluid. A review.


Determination of human growth hormone (H.G.H.) activity in the amniotic fluid in foeto-maternal disease.


Dihydrofolate reductase inhibitors as antimicrobial agents and their potentiation by sulfonamides.


The activation of  -galactosidase by divalent and monovalent cations. Transient- and steady-state studies.


Substrate- and antibiotic-binding sites at the peptidyl-transferase centre of Escherichia coli ribosomes. Studies on the chloramphenicol. lincomycin and erythromycin sites.


Ribosomal proteins. Isolation of proteins from 50S ribosomal subunits of Escherichia coli.


Ribosomal proteins. Isolation of the proteins from 30S ribosomal subunits of Escherichia coli.


Fate of exogenous DNA in Arabidopsis thaliana. Translocation and integration.


Tobacco mosaic virus specific immunoglobulins from horse serum. I. Physical and chemical characterization.


Cellular and subcellular study of the in vitro immune response.


Abortive infection by bacteriophage BF23 due to the colicin Ib factor. I. Genetic studies of nonrestricted and amber mutants of bacteriophage BF23.


Combined human menopausal gonadotropin therapy and donor insemination.


Structural and regulatory control of aryl sulfatase in Neurospora: the use of interspecific differences in structural genes.


Exchange reactions catalyzed by acetate kinase.


On the mechanism of 5-enolpyruvylshikimate 3-phosphate synthetase.


Crystallization with hapten of the Fab' fragment from a mouse IgA myeloma protein with antidinitrophenyl activity.


Activation of selectively reduced and alkylated trypsinogen and enzymic properties of the activated product.


Computer aided diagnosis: a learning model.


Immunological rejection as a cause of abortion.


Immunological aspects of foeto-maternal relations in lower vertebrates.


To Otto E. Aufranc, MD--an appreciation.


The international metric system and medicine.


Home dialysis and renal transplantation in childhood.


Geoffrey Gossip Harkness.

Geoffrey Gossip Harkness.


Leonard Arthur Elmslie Dixon.

Leonard Arthur Elmslie Dixon.


Etiology and pathogenesis of rheumatoid arthritis. Current lines of investigation.


Rheumatoid arthritis of the spinal column. Pathologic aspects and treatment.


Rheumatoid hand repairs.

Rheumatoid hand repairs.


Validation and extension of the contigency model of leadership effectiveness: a review of empirical findings.


Ornithine-vasopressin (POR-8) as a vasoconstrictor in anesthetics used for ordinary dental treatment.


A methodological study of oral vestibular sulcus reproduction.


Pyruvate kinase deficiency.

Pyruvate kinase deficiency.


Dr. John Morgan's 18th-century journey abroad, retraced in 1970.


Reflections on "the subclavian steal".

Reflections on "the subclavian steal".


Soft or hard, dependent or addicted?

Soft or hard, dependent or addicted?


Deprivation and progress.

Deprivation and progress.


Bilateral jugular venous blood flow by thermal dilution.


Officers of the American Roentgen Ray Society and the American Radium Society.


Renal homotransplantation: spectrum of angiographic findings of the kidney.


Roscoe P. O'Bannon, M.D. 1896-1971.

Roscoe P. O'Bannon, M.D. 1896-1971.


The particulate graft in tumor surgery.

The particulate graft in tumor surgery.


Auricular cancer. Some surgical and pathologic considerations.


Simplified method of canine orthotopic hepatic transplantation.


A tracheostomy cuff designed to prevent suffocation.


Perilymphatic communication routes in guinea pig cochlea.


Combined effects of noise and kanamycin.


The role of vasoconstriction in noise-induced hearing loss.


Surgical management of localized thoracic infections in immunosuppressed patients.


Chylothorax.

Chylothorax.


Morphological study of a case of complete, isolated, and asymptomatic agenesis of the corpus callosum.


Some morphological characteristics of the developing pyramidal cell as observed in vitro in cultures of human, fetal, cerebral, cortical tissue.


The American Cancer Society's professional education conferences. An historical review.


Antiquity of breast cancer.

Antiquity of breast cancer.


Newer concepts in the management of patients with breast cancer.


Identification of high risk groups in breast cancer.


Oral contraceptives and pathologic changes in the breast.


Morphological evidence for immune response to breast cancer. An historical review.


Thymic antigen-reactive cells do not specify serological properties of antibody.


Frequency of antigen-sensitive cells to thymus-independent antigens.


Immune response of the hamster to oral and parenteral immunization.


The immunosuppressive capacity of alloantisera in mice, including sera directed primarily against thymic antigens.


Identification of mouse thymus antigen recognition function in a minor, low-density, low-theta cell subpopulation.


Haydn Jones Morris.

Haydn Jones Morris.


Hamilton Bailey.

Hamilton Bailey.


Coronary hemodynamics during successive elevation of heart rate by pacing in subjects with angina pectoris.


Use of exercise testing for diagnostic and functional evaluation of patients with arteriosclerotic heart disease.


The assay of chlorpromazine and metabolites in blood, urine, and other tissues.


Inadequate reimbursement for Medicaid.

Inadequate reimbursement for Medicaid.


Interracial attitudes of younger and older adults in a biracial population.


Dermal arthroplasty.

Dermal arthroplasty.


The Maribor method of burns treatment. A report on the work of Janzekovic at Maribor, Yugoslavia.


New directions in the chemistry of natural products: the organic chemist as a pathfinder for biochemistry and medicine.


Delayed primary suture in flexor tendon division.


Air Vice-Marshal George H. Morley.

Air Vice-Marshal George H. Morley.


In vitro protection against radiation damage to template activity in DNA synthesis.


Temperature dependence of radiation sensitivity in the dry state. 3. Investigations with isolated infectious Phi-X174-DNA.


Pulse radiolysis studies of the radiosensitizer Nor-pseudopelletierine-N-oxyl (NPPN). I. Radiation chemistry.


Protection of RNA polymerase against ionizing radiation by mixed disulphide formation.


Isolation of the luteinizing hormone and follicle-stimulating hormone-releasing hormone from porcine hypothalami.


Purification and characterization of a deoxyribonucleic acid polymerase from rat liver.


A modified technique for surgical repair of myelomeningocele.


Will financing determine program?

Will financing determine program?


Roentgen videodensitometric measure of coronary blood flow. Determination from simultaneous indicator-dilution curves at selected sites in the coronary circulation and in coronary artery-saphenous vein grafts.


Proper perspective on vesicoureteral reflux.


Transplantation of organs other than kidneys.


The problem of Newcastle disease.

The problem of Newcastle disease.


Simplicity of mammalian regulatory systems inferred by single gene determination of sex phenotypes.


Electron density profiles of nerve myelin.


Effect of ethylene on root extension of cereals.


Serum-mediated immunological non-reactivity between histoincompatible cells in tetraparental mice.


Use of a sustained-release multiple emulsion to extend the period of radio protection conferred by cysteamine.


Comparative psychotomimetic effects of stereoisomers of amphetamine.


Reaction of metallic copper with biological substrates.


Incidence of R +  Escherichia coli in coastal bathing waters of Britain.


Contrast illusions in perspective.

Contrast illusions in perspective.


Intrahypothalamic adrenergic and cholinergic injection effects on temperature and ingestive behavior in the rat.


Recent advances in surgery of the fallopian tubes.


Objective effects of dexamphetamine and amobarbital and their relations to psychasthenic personality traits.


The effect of LSD on sleep-deprived men.


The concomitant effects of mild sleep loss and an anticholinergic drug.


Rhode Island's first woman physician.

Rhode Island's first woman physician.


Effects of N-acetyl dimethoxyphenethylamine (NADMPEA) in man.


The medical humanists--Linacre and Caius.


Histopathology of Crohn's disease.

Histopathology of Crohn's disease.


Analogies between lymphocyte receptors and the resulting humoral antibodies.


Specific fractionation of immunocompetent cells.


Influence of vaginal flora on body temperature during the puerperium.


Comparison between nitrous oxide and methoxyflurane for obstetrical analgesia.


Serratia marcescens endophthalmitis.

Serratia marcescens endophthalmitis.


A trephine for primary corneal transplant in repair of corneal laceration.


The semicentenary of insulin.

The semicentenary of insulin.


Release of pituitary melanocyte-stimulating hormone by the oxytocin fragment, H-Cys-Tyr-Ile-Gln-Asn-Oh.


Phosphoenolpyruvate carboxylase of E. coli: discrimination of regulatory sites for four kinds of allosteric effectors by the method of genetic desensitization.


Glutamate-binding protein and its relation to glutamate transport in Escherichia coli K-12.


Mitochondrial DNA-directed RNA polymerase from Saccharomyces cerevisae mitochondria.


Effect of siomycin on the acceptor site of Escherichia coli ribosomes.


Synthesis and characterisation of a decapeptide having LH-RH-FSH-RH activity.


Synthesis of the porcine LH- and FSH-releasing hormone by the solid-phase method.


Isolation and properties of  -ketoglutarate dehydrogenase complex from baker's yeast (Saccharomyces cerevisiae).


The pancreatic  -cell recognition of insulin secretagogues. II. Site of action of tolbutamide.


A new crystalline growth factor for mammalian cells in vitro, isolated from a commercial peptone.


Isolation and partial characterization of a chromophore-peptide fragment from pepsin digests of phytochrome.


On the activation of pepsinogen.

On the activation of pepsinogen.


A lipid requirement for induction of alkaline phosphatase, one of periplasmic enzymes, in Escherichia coli.


Properties of DNA isolated from organs of calves treated with S-(1,2-dichlorovinyl)-L-cysteine. 3. Template activity for bacterial RNA polymerase.


Reconstitution in vitro of membranous particles by complementation between extracts of chl-r mutants in Escherichia coli K12.


Lac repressor binding to operator analogues: comparison of poly(d(A-T)), poly(d(A-BrU)), and poly(d(A-U)).


A thermostable protein factor acting on in vitro DNA transcription.


Luteinizing hormone releasing activity in the hypothalamus of anestrous and cyclic ewes.


Effects of ergotamine tartrate on prolactin and growth hormone secretion by rat adenohypophysis in vitro.


Phagocytosis as the basis of accelerated sperm disappearnace ligated IUD-bearing uterine horns of the ewe.


Smooth muscle antibody in malignant disease. Smooth muscle antibody at titres of 1/10 or more was found in 54 (67.5%) out of 80 patients with malignant disease and in 9 (20%) out of 46 controls. The incidence of S.M. antibody ranged from 18/30 (60%) in malignant melanoma to 7/8 (83%) in carcinoma of the ovary. The presence of this antibody is possibly related to changes in the malignant cell membrane.A new antibody directed at an antigen presumed to be located in bile canaliculi among other sites is described.


Controlled clinical trial of clofazimine in untreated lepromatous leprosy. A comparison of clofazimine and dapsone in the management of untreated lepromatous leprosy showed no significant differences between the two drugs in terms of morphological and bacterial indices. The incidence of erythema nodosum leprosum was similar in the two groups. Since dapsone is cheaper than clofazimine it remains the drug of choice for the routine management of untreated lepromatous leprosy.


The comparative effect of busulphan ('Myleran') and aminochlorambucil on haemopoietic colony forming units in the rat.


The use of  59 Fe uptake for the evaluation of cell proliferation in spleen colonies.


The efficiency of the assay for haemopoietic colony forming cells.


The clinical biochemistry of phosphorus.


The significance of bile acids in gastrointestinal and hepatic disease.


A micro-procedure for the preparation of highly purified  14 C-,  35 S-, and  32 P-labeled transcriptases from E. coli.


Preparation of B cell deficient guinea pig islets of Langerhans.


Increase of plasma insulin after intravenous injection of trypsin in rat.


Studies on the effect of combined growth hormone and cortisol on the insulin response to glucose in the hypophysectomized dog.


Phosphoglucomutase mutants of Escherichia coli K-12. Bacteria with strongly depressed phosphoglucomutase (EC 2.7.5.1) activity are found among the mutants of Escherichia coli which, when grown on maltose, accumulate sufficient amylose to be detectable by iodine staining. These pgm mutants grow poorly on galactose but also accumulate amylose on this carbon source. Growth on lactose does not produce high amylose but, instead, results in the induction of the enzymes of maltose metabolism, presumably by accumulation of maltose. These facts suggest that the catabolism of glucose-1-phosphate is strongly depressed in pgm mutants, although not completely abolished. Anabolism of glucose-1-phosphate is also strongly depressed, since amino acid- or glucose-grown pgm mutants are sensitive to phage C21, indicating a deficiency in the biosynthesis of uridine diphosphoglucose or uridine diphosphogalactose, or both. All pgm mutations isolated map at about 16 min on the genetic map, between purE and the gal operon.


Characterization of mutants of Escherichia coli temperature-sensitive for ribonucleic acid regulation: an unusual phenotype associated with a phenylalanyl transfer ribonucleic acid synthetase mutant. A mutant strain AA-522, temperature-sensitive for protein synthesis, was isolated from a stringent strain (CP-78) of Escherichia coli K-12. The mutant strain has a relaxed phenotype at the nonpermissive growth temperature. Protein synthesis stops completely at 42 C, whereas the rate of ribonucleic acid (RNA) synthesis is maintained at 20% of the 30 C rate. Sucrose-gradient centrifugation analysis of RNA-containing particles formed at 42 C indicated the presence of "relaxed particles." These particles possess 16S and 23S RNA and are precursors to normal 50S and 30S ribosomal subunits. A search for the temperature-sensitive protein responsible for the halt in protein synthesis implicated phenylalanyl transfer RNA (tRNA) synthetase. Essentially no enzyme activity is detected in vitro at 30 or 40 C. Analysis of phenylalanyl tRNA synthetase activity in revertants of strain AA-522 indicated the presence of intragenic suppressor mutations. Revertants of strain AA-522 analyzed for the relaxed response at 42 C were all stringent; strain AA-522 was stringent at 30 C. These data indicate that a single mutation in phenylalanyl tRNA synthetase is responsible for both a block in protein synthesis and the relaxed phenotype at 42 C.


Potassium transport loci in Escherichia coli K-12. Mutants of Escherichia coli K-12 requiring considerably elevated concentrations of potassium for growth are readily obtained as double mutants combining a kdp mutation with a mutation in one or more of five other loci. These loci are referred to as trk, for transport of K, because these mutations result in alterations in K transport. The kdp mutation is essential in the isolation and identification of this type of mutant; in a Kdp(+) strain, the presence of a trk mutation does not prevent growth of the strain in media containing very low concentrations of K. The trk loci are widely scattered over the E. coli chromosome; none of them is very near any other trk locus or near the kdp genes.


Binding of radioactive benzylpenicillin to sporulating Bacillus cultures: chemistry and fluctuations in specific binding capacity. The chemistry of the binding of (14)C-benzylpenicillin to sporulating cultures of Bacillus megaterium and B. subtilis is similar to that in a 4-hr vegetative culture of Staphylococcus aureus. Unlabeled penicillins prevent the binding of (14)C-benzylpenicillin, but benzylpenicilloic acid and benzylpenilloic acid do not. Bound antibiotic can be removed from cells with neutral hydroxylamine at 25 C. Sporulating cultures display two intervals of enhanced binding, whereas binding to stationaryphase S. aureus cells remains constant. The first period of increased binding activity occurs during formation of the spore septum or cell wall primordium development, and the second coincides with cortex biosynthesis.


Mapping the gene determining ornithine transcarbamylase and its operator in Escherichia coli B. The gene determining ornithine transcarbamylase in Escherichia coli B is argI, not argF. The argI gene has been located at 84 min on the linkage map, close to the gene for aspartate transcarbamylase, with neighboring markers in clockwise order fdp pyrB argI valS. A mutation in its operator locus, argO(I), has been mapped between argI and valS, so that this gene, unlike the argCBH portion of the argECBH cluster, appears to be oriented in the same direction as most of the other known E. coli operons.


Biochemical characterization of the ctr mutants of Escherichia coli. A test procedure based on complementation in mixed extracts is described for the assay of heat-stable protein and enzyme I of the phosphoenolpyruvate-dependent phosphotransferase system. The test was used to assay a collection of pleiotropic carbohydrate mutants of Escherichia coli (ctr mutants) and revertants of these mutants. All mutants were found to lack enzyme I of the phosphoenolpyruvate-dependent transferase system. Revertants of these mutants to complete wild phenotype regained enzyme I-forming ability. Reversion to partial wild type was not accompanied by restoration of enzyme I-forming ability.


Extent of host deletions associated with bacteriophage P2-mediated eduction. A series of independent Escherichia coli K eductants has been isolated and tested to determine the extent of their deletions. The deletions cover the P2 prophage in location H, the his operon, a suppressor of the recBC phenotype (sbcB), the gene for gluconate-6-phosphate dehydrogenase (gnd), a locus involved in cell wall synthesis (rfb), and in some cases all or part of genes involved in methylgalactoside uptake (mglP). One end of the deletion, the P2 prophage end, appears to be the same for all eductants. The other end, however, can be located before, within, and after the mglP locus.


Mechanism of action of rifampin on Mycobacterium smegmatis. Deoxyribonucleic acid (DNA)-dependent ribonucleic acid (RNA) polymerase (EC 2.7.7.6) isolated from a rifampin-sensitive strain of Mycobacterium smegmatis was 90% inhibited by 1 mug of rifampin per ml; enzyme from a rifampin-resistant mutant was not affected by this concentration of antibiotic. Inhibition of phenylalanine-1-(14)C incorporation by rifampin in growing cultures was complete about 6 min after addition of antibiotic. Under the same conditions, uracil-2-(14)c incorporated was blocked after 1.5 to 2 min. Rifampin kills M. smegmatis very slowly. When rifampin-inhibited cultures were transferred to a rifampin-free medium, there was a partial resumption of uracil-2-(14)C incorporation, even in the presence of chloramphenicol. We conclude that a primary event in the inhibition of M. smegmatis by rifampin is the block of DNA-dependent RNA polymerase.


Isolation and partial characterization of temperature-sensitive Escherichia coli mutants with altered leucyl- and seryl-transfer ribonucleic acid synthetases. Two temperature-sensitive mutants of Escherichia coli have been found in which the conditional growth is a result of a thermosensitive leucyl-transfer ribonucleic acid (tRNA) synthetase and seryl-tRNA synthetase, respectively. The corresponding genetic loci, leuS and serS, cotransduce with lip and serC, respectively. As a result of the mutationally altered leucyl-tRNA synthetase, some leucine-, valine-, and isoleucine-forming enzymes were derepressed. Thus, leucyl-tRNA synthetase is involved in the repression of the enzymes needed for the synthesis of branched-chain amino acids.


Pigmentation and acriflavine resistance in Serratia marcescens. Stable, orange, acriflavine-resistant variants were selected by treatment of a wild-type, red, acriflavine-sensitive strain of Serratia marcescens with acriflavine. Visible, ultraviolet, infrared, and nuclear magnetic resonance spectra of purified pigment from the red strain were identical to those of the pigment from the orange strain, and the orange mutant was not due to a mutation affecting the structure of the pigment, prodigiosin. The color of the red strain was not affected by variations in pH between 5.0 and 8.0, whereas the color of the orange mutant changed from pink to orange over the same pH range. This variation was mimicked by the pH-induced variation in color of prodigiosin purified from either the red, wild-type or the orange, mutant strains. Density-gradient centrifugation of cell fragments after ultrasonic disintegration resulted in characteristic pigmented bands. Biochemical characterization of these pigmented bands showed that they contained pigment and a protein component, but no lipids, polysaccharides, sugars, glucosamine, or phosphates were detected. Further fractionation of these pigmented bands by zone electrophoresis on a sucrose density gradient indicated that some pigment in S. marcescens was specifically attached to protein components.


Effects of hydrostatic pressure and temperature on the uptake and respiration of amino acids by a facultatively psychrophilic marine bacterium. Studies of pressure and temperature effects on glutamic acid transport and utilization indicated that hydrostatic pressure and low temperature inhibit glutamate transport more than glutamate respiration. The effects of pressure on transport were reduced at temperatures near the optimum. Similar results were obtained for glycine, phenylalanine, and proline. Pressure effects on the transport systems of all four amino acids were reversible to some degree. Both proline and glutamic acid were able to protect their transport proteins against pressure damage. The data presented indicate that the uptake of amino acids by cells under pressure is inhibited, which is the cause of their inability to grow under pressure.


Mutants of Escherichia coli unable to make protein at 42 C. Members of a collection of mutants of Escherichia coli unable to form colonies on nutrient agar at 42 C have been characterized on the basis of their growth response to a shift from 32 to 42 C in liquid medium. Forty-four mutants, which show an abrupt, nonlethal cessation of growth when moved to the restrictive temperature, have been characterized with respect to the effect of the mutation responsible for temperature sensitivity on deoxyribonucleic acid, ribonucleic acid, and protein synthesis. In 12 mutants, the mutation causing temperature sensitivity of growth primarily affects protein synthesis, in each case through an altered aminoacyl-transfer ribonucleic acid synthetase. Mutants with temperature-sensitive glutamyl-, phenylalanyl-, and valyl-transfer ribonucleic acid synthetases have been obtained, and the genes specifying these enzymes have been mapped by conjugation and transduction. Another mutant has been shown to possess a temperature-sensitive tryptophanyl-transfer ribonucleic acid synthetase, but this is not responsible for inability to grow at 42 C on media containing tryptophan.


Stimulation of ribonucleic acid synthesis by chloramphenicol in a rel +  aminoacyl-transfer ribonucleic acid synthetase mutant of Escherichia coli. Escherichia coli strain 9D3 possesses a highly temperature-sensitive valyl-transfer ribonucleic acid (tRNA) synthetase (EC 6.1.1.9). Since 9D3 is a rel(+) strain, it cannot carry out net RNA synthesis at high temperature. A 100-mug amount of chloramphenicol (CAP) per ml added in the absence of valine cannot stimulate RNA synthesis. Either 300 mug of CAP or 100 mug of CAP plus 50 mug of valine per ml, however, promotes nearly maximal RNA synthesis. These results can be understood as follows. (i) Valyl-tRNA is required for net RNA synthesis, (ii) the synthetase lesion is incomplete, (iii) the rate of mutant acylation of tRNA(val) at high temperature is valine-dependent, and (iv) the CAP concentration determines the rate of residual protein synthesis. Data are also presented which demonstrate that the rate of net RNA synthesis can greatly increase long after the addition of CAP, if the amount of valyl-tRNA increases.


Growth of Escherichia coli on short-chain fatty acids: growth characteristics of mutants. The parent Escherichia coli K-12 is constitutive for the enzymes of the glyoxylate bypass and adapts to growth on long-chain fatty acids (C(12) to C(18)). It does not utilize medium-chain (C(6) to C(11)) or short-chain (C(4), C(5)) n-monocarboxylic acids. Several mutants of this strain which grow using short- or medium-chain acids, or both, as the sole carbon source were selected and characterized. One mutant (D(1)) synthesizes the beta-oxidation enzymes constitutively and grows on medium-chain but not on short-chain acids. A second (N(3)) is partially derepressed for synthesis of these enzymes and grows both on medium-chain and on short-chain acids. Secondary mutants (N(3)V(-), N(3)B(-), N(3)OL(-)) were derived from N(3). N(3)V(-) grows on even-chain but not on odd-chain acids and exhibits a lesion in propionate oxidation. N(3)B(-) grows on odd-chain but not on even-chain acids and exhibits no crotonase activity as assayed by hydration of crotonyl-CoA. N(3)OL(-) grows on acetate and propionate but does not utilize fatty acids C(4) to C(18); it exhibits multiple deficiencies in the beta-oxidation pathway. Growth on acetate of N(3), but not of the parent strain, is inhibited by 4-pentenoate. Revertants of N(3) which are resistant to growth inhibition by 4-pentenoate (N(3)PR) exhibit loss of ability to grow on short-chain acids but retain the ability to grow on medium-chain and long-chain acids. The growth characteristics of these mutants suggest that in order to grow at the expense of butyrate and valerate, E. coli must be (i) derepressed for synthesis of the beta-oxidation enzymes and (ii) derepressed for synthesis of a short-chain fatty acid uptake system.


Phenotypic restoration by molybdate of nitrate reductase activity in chlD mutants of Escherichia coli. ChlD mutants of Escherichia coli are pleiotropic, lacking formate-nitrate reductase activity as well as formate-hydrogenlyase activity. Whole-chain formate-nitrate reductase activity, assayed with formate as the electron donor and measuring the amount of nitrite produced, was restored to wild-type levels in the mutants by addition of 10(-4)m molybdate to the growth medium. Under these conditions, the activity of each of the components of the membrane-bound nitrate reductase chain increased after molybdate supplementation. In the absence of nitrate, the activities of the formate-hydrogenlyase system were also restored by molybdate. Strains deleted for the chlD gene responded in a similar way to molybdate supplementation. The concentration of molybdenum in the chlD mutant cells did not differ significantly from that in the wild-type cells at either low or high concentrations of molybdate in the medium. However, the distribution of molybdenum between the soluble protein and membrane fractions differed significantly from wild type. We conclude that the chlD gene product cannot be a structural component of the formate-hydrogenlyase pathway or the formate-nitrate reductase pathway, but that it must have an indirect role in processing molybdate to a form necessary for both electron transport systems.


Growth of Escherichia coli on short-chain fatty acids: nature of the uptake system. Mutants of Escherichia coli K-12 which grow on butyrate and valerate were studied with respect to uptake of these substrates. To utilize short-chain and medium-chain fatty acids, E. coli must synthesize the beta-oxidation enzymes constitutively. In addition, growth on the C(4) and C(5) acids requires a second mutation which permits entry of these substrates. At pH 5, both in the parent and mutant strains, butyrate and valerate penetrate as the undissociated acids but appear not to be activated and thus inhibit growth. At pH 7, the parent strain is not permeable to the anions, whereas the mutant concentrates these substrates. There appear to be two components of the uptake system, a nonspecific diffusion component and an energy-linked activating enzyme. Two mutant types which take up short-chain fatty acids are described. One synthesizes the uptake system constitutively and is inhibited by 4-pentenoate when cultured on acetate. In the other, the uptake system is inducible, and the strain is pentenoate-resistant when grown on acetate but pentenoate-sensitive when cultured on butyrate or valerate.


RecA + -dependent repair of gamma-ray damage to Escherichia coli does not require recombination between existing homologous chromosomes. Chemostat-grown Escherichia coli showed recA(+)-dependent resistance to gamma radiation even though between 50 and 75% of the population possessed only a single unreplicated genome, suggesting that recombination between homologous chromosomes before replication is not necessary for manifestation of recA(+)-dependent resistance to gamma radiation.


Analysis for antigenic similarities among the 30S ribosomal proteins of Escherichia coli. Antiserum was made against a single 30S protein, 30S-7. The amount of complement fixed by total 30S protein in the presence of this antiserum indicated that protein 30S-7 was the major antigen in the mixture of proteins. Each of the 30S ribosomal proteins was tested for cross-reactivity with anti-30S-7. This was done by determining if any of the other 30S proteins inhibited complement fixation by 30S-7. None of the other 30S proteins was found to inhibit complement fixation by 30S-7, indicating that 30S-7 is antigenically distinct from the other proteins.


Relationship between sex-pili formation and macarbomycin sensitivity in Escherichia coli. The presence in Escherichia coli strains of derepressed sex factors determining F-type pili formation was found to increase their sensitivity to macarbomycin.


Evidence that the majority of leucine transfer ribonucleic acid is not involved in repression in Salmonella typhimurium. Leucine transfer ribonucleic acid (tRNA) was almost fully charged, and the isoleucine-valine and leucine enzymes remained derepressed when trifluoroleucine was added to a leucine auxotroph. High levels of charged leucine tRNA and derepression were also found in a leucyl-tRNA synthetase mutant.


The role of three cytoplasmic fibers in BHK-21 cell motility. I. Microtubules and the effects of colchicine. Microtubule breakdown in the presence of 5 or 40 microg/ml of colchicine is observed in BHK-21/C13 fibroblast-like cells. Several morphological and physiological effects are noted in the absence of microtubules: (a) the cells transform from fibroblast-like to epithelial-like cells; (b) the normal pattern of intracellular birefringence changes and a juxtanuclear cap of birefringent filaments is formed; (c) time-lapse cinematography demonstrates that cell locomotion is inhibited in colchicine-treated cells, even though membrane ruffling persists. The results are discussed in terms of the specific roles of microtubules in cultured cell motility and possible functional relationships of the three types of cytoplasmic fibers seen in BHK-21 cells.


Intrinsic birefringence of glycerinated myofibrils. Patterns of intrinsic birefringence were revealed in formalin-fixed, glycerinated myofibrils from rabbit striated muscle, by perfusing them with solvents of refractive index near to that of protein, about 1.570. The patterns differ substantially from those obtained in physiological salt solutions, due to the elimination of edge- and form birefringence. Analysis of myofibrils at various stages of shortening has produced results fully consistent with the sliding filament theory of contraction. On a weight basis, the intrinsic birefringence of thick-filament protein is about 2.4 times that of thin-filament protein. Nonadditivity of thick- and thin-filament birefringence in the overlap regions of A bands may indicate an alteration of macromolecular structure due to interaction between the two types of filaments.


Frozen thin sections of fresh tissue for electron microscopy, with a description of pancreas and liver. A simple method has been developed that allows frozen thin sections of fresh-frozen tissue to be cut on a virtually unmodified ultramicrotome kept at room temperature. A bowl-shaped Dewar flask with a knifeholder in its depths replaces the stage of the microtome; a bar extends down into the bowl from the microtome's cutting arm and bears the frozen tissue near its lower end. When the microtome is operated, the tissue passes a glass or diamond knife in the depths of the bowl as in normal cutting. The cutting temperature is maintained by flushing the bowl with cold nitrogen gas, and can be set anywhere from about -160 degrees C up to about -30 degrees C. The microtome is set for a cutting thickness of 540-1000 A. Sections are picked up from the dry knife edge, and are placed on membrane-coated grids, flattened with the polished end of a copper rod, and either dried in nitrogen gas or freeze-dried. Throughout the entire process the tissue is kept cold and does not come in contact with any solvent. The morphology seen in frozen thin sections of rat pancreas and liver generally resembles that in conventional preparations, although freezing damage and low contrast limit the detail that can be discerned. Among unusual findings is a frequent abundance of mitochondrial granules in material prepared by this method.


Basal bodies, but not centrioles, in Naegleria. Amebae of Naegleria gruberi transform into flagellates whose basal bodies have the typical centriole-like structure. The amebae appear to lack any homologous structure, even during mitosis. Basal bodies are constructed during transformation and, in cells transforming synchronously at 25 degrees C, they are first seen about 10 min before flagella are seen. No structural precursor for these basal bodies has been found. These observations are discussed in the light of hypotheses about the continuity of centrioles.


Septate and gap junctions in molluscan gill epithelium.


Further observations on the occurrence of nexuses in benign and malignant human cervical epithelium. An estimate is made of the frequency of occurrence of nexuses ("gap junctions") in a spectrum of human cervical epithelia, ranging from normal to malignant, since a deficiency of nexuses may be important in abnormal cell-to-cell communication in malignant tissues. The normal cervical epithelium has approximately ten nexuses per cell in the basal layer of proliferating cells and 200 nexuses per cell in the more differentiated intermediate zone. Nexuses are rare between invasive malignant epithelial cells (carcinoma cells). In many areas of cell proliferation near the edge of the tumor mass, fewer than one nexus per cell is present. However, up to four nexuses per cell can be found in some well differentiated regions of invasive carcinoma. Preinvasive malignant epithelia (severe dysplasia and carcinoma-in situ) have as few nexuses as invasive carcinoma. In abnormal but benign epithelia (squamous metaplasia and mild dysplasia), nexuses are abundant. The data indicate that a decrease in number of nexuses correlates with the severity of the morphological alteration in the dysplastic epithelium. Also the deficiency of nexuses in groups of carcinoma cells can occur many cell generations before the development of invasion of the malignant epithelium into the connective tissue. The diminution of nexuses before invasion suggests that a deficiency of nexuses may be one of the important factors in eventually permitting the development of the diffusely infiltrating type of invasion which is characteristic of highly malignant tumors such as squamous carcinomas.


The occurrence of synaptonemal complexes in the slime mold Echinostelium minutum de Bary.


[Surfaces of stone models made in elastic material impression. I. Stone model surfaces and treatment of alginate impressions].


A histological study of the incidence of plasma cells and lymphocytes in human gingival tissues.


Drug biotransformation interactions in man. V. Acetaminophen and salicylic acid.


The jubilee of the Commonwealth Health Department.


Kidneys for transplants.

Kidneys for transplants.


Surgeon John Harris's grave.

Surgeon John Harris's grave.


Nicotine and cardiogenesis. An experimental study.


Xanthogranulomatous pyelonephritis in childhood with Ascaris lumbricoides infestation.


Edwardsiella tarda associated with human disease.


Radioisotope labels for the study of leukocyte kinetics. II.


Preservation of pig liver using hypothermia, hyperbaric oxygenation and perfusion.


Multienzyme systems.

Multienzyme systems.


Historical notes on rheumatology.

Historical notes on rheumatology.


Some aspects of metabolic bone disease related to rheumatology.


Hip-joint surgery in the twentieth century.


Vineland scale of ego development.

Vineland scale of ego development.


Renal circulation in rats treated with hexadimethrine bromide.


Conformation of viral nucleic acids in situ.


Salmonella enteritis. I. Role of reduced gastric secretion in pathogenesis.


Conduction disturbances of the left bundle branch system and their relationship to complete heart block. I. A review of experimental, electrophysiologic and electrocardiographic aspects.


Schools of public health in the USA and Canada. (Year ending June 1971).


Hirschsprung's disease.

Hirschsprung's disease.


The Sociological Section of the American Public Health Association, 1910-1922.


A selected public health bibliography with annotations.


The structure of developing bone marrow sinuses in extramedullary autotransplant of the marrow in rats.


Residents and residencies.

Residents and residencies.


Early Arizona Medical Association activities.


Preoperative and postoperative cardiac output determinations using an instantaneous pulmonary capillary blood flow method.


An active site peptide from pepsin C.

An active site peptide from pepsin C. Porcine pepsin C is inactivated rapidly and irreversibly by diazoacetyl-dl-norleucine methyl ester in the presence of cupric ions at pH values above 4.5. The inactivation is specific in that complete inactivation accompanies the incorporation of 1mol of inhibitor residue/mol of enzyme and evidence has been obtained to suggest that the reaction occurs with an active site residue. The site of reaction is the beta-carboxyl group of an aspartic acid residue in the sequence Ile-Val-Asp-Thr. This sequence is identical with the active-site sequence in pepsin and the significance of this in terms of the different activities of the two enzymes is discussed.


Continuous positive-pressure ventilation for children with respiratory failure.


Clinical application of the lactic dehydrogenase zymogram in anesthesia.


Location of aromatic amino acids and belix content in Escherichia coli ribonucleic acid polymerase. 1. The perturbing effect of glycerol on the direct spectrum of Escherichia coli DNA-dependent RNA polymerase has been studied. 2. By comparison with model compounds and with the unfolded polymerase in 3.8m-urea it was possible to determine the ratio of tyrosine and tryptophan residues present. On reduction of the urea-treated enzyme with 2-mercaptoethanol, no further change in the difference spectrum occurred. 3. The amino acid composition of the enzyme is given. 4. In the intact protein approx. 30% of the tryptophan and 54% of the tyrosine residues were exposed. In conjunction with the extinction value and molecular weight this corresponded to 7 tryptophan residues and 57 tyrosine residues on the surface and 16 tryptophan residues and 48 tyrosine residues ;buried'. 5. The optical rotatory dispersion of the enzyme was unaffected by 20% glycerol. 6. The helix content calculated from Moffit plots over 560-300nm was 13%, and from the 233nm trough 13%.


Clinical aspects of the various forms of nonmedical use of drugs. II.


The Tenth Annual Baxter-Travenol Lecture.


Seventh Annual Becton, Dickinson and Company Oscar Schwidetzky Memorial Lecture.


Antiemetic effectiveness of haloperidol in human volunteers challenged with apomorphine. Guest discussion.


Vitamin C and the common cold.

Vitamin C and the common cold.


The relationship between carbohydrate content and enzymic activity of yeast invertase.


The smooth lipopolysaccharide character of 1,4,(5),12 and 1,9,12 transductants formed as hybrids between groups B and D of salmonella.


Fingerprint maps of tryptic peptides from subunits of Escherichia coli and T 4 -modified DNA-dependent RNA polymerases.


A correlation of changes in host and T 4  bacteriophage specific RNA synthesis with changes of DNA-dependent RNA polymerase in Escherichia coli infected with bacteriophage T 4 .


Physiology, homoeostasis and ageing.

Physiology, homoeostasis and ageing.


The role of platelets in passively transferred endotoxin resistance.


Public health hazards from environmental chemical carcinogens, mutagens and teratogens.


Biodynamic models and their applications.


Intestinal absorption in the "contaminated small-bowel syndrome".


Report of the panel of the colloquium on selected infectious diseases of swine.


MEDLARS.

MEDLARS.


Antigens common to human and bacterial cells: urinary tract pathogens.


Pulmonary shunt determination: a comparison between oxygen inhalation (Berggren) and xenon-133 methods.


Hypothalamic influences on prolactin secretion in man.


Patterns of bile acids and microflora in the human small intestine.


Infectious drug resistance in Thailand. II. Infectious drug resistance in Escherichia coli isolated from healthy adults and hospitalized patients in Bangkok.


The value of pharmacological studies in the development of new antinematodal drugs.


Adaptation of the malaria parasite to its environment during the life cycle.


Structural analogs of lysergic acid.

Structural analogs of lysergic acid.


Toxogonin: oral administration to man.

Toxogonin: oral administration to man.


Dysfunctional antepartum nutrition.

Dysfunctional antepartum nutrition.


Nutritive influences upon reproduction.

Nutritive influences upon reproduction.


Metabolic abnormalities in uremia.

Metabolic abnormalities in uremia.