abstract：:Mitochondrial membrane potentials and resistances have been determined under various metabolic conditions by the use of piezoelectric-driven microelectrodes. The mean state 3 potentials (about +19 mv) are higher than the potentials in state 4 (about +9 mv). DNP in uncoupling concentrations or KCN have no significant e...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Tupper JT,Tedeschi H

更新日期：1969-07-01 00:00:00

abstract：:Synthetic bradykinin, a nonapeptide formed from alpha-2 globulin in plasma, injected intra-arterially or intraperitoneally in cats in doses of 10-50 mug, evoked activity in the central nervous system in pathways associated with the signaling of pain. Similar injections of bradykinin in intact normal cats and dogs evok...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Lim RK,Krauthamer G,Guzman F,Fulp RR

更新日期：1969-07-01 00:00:00

abstract：:Light chains were obtained from IgG rabbit antibodies to the group-specific carbohydrates of groups A and C streptococci. An analysis of the amino acid alternatives which exist at the first three positions of the N-terminus in both light-chain preparations shows a marked restriction in amino acid sequence heterogeneit...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Hood L,Lackland H,Eichman K,Kindt TJ,Braun DG,Krause RM

更新日期：1969-07-01 00:00:00

abstract：:The rate of derepressed synthesis of a membrane protein required for lactose transport (M protein) by Escherichia coli is increased in response to increased gene dosage to the same extent as the rates of synthesis of beta-galactosidase and galactoside acetylase. However, elevated gene dosage does not increase beta-gal...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Fox CF

更新日期：1969-07-01 00:00:00

abstract：:The law of the iterated logarithm provides a family of bounds all of the same order such that with probability one only finitely many partial sums of a sequence of independent and identically distributed random variables exceed some members of the family, while for others infinitely many do so. In the former case, the...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Slivka J

更新日期：1969-06-01 00:00:00

abstract：:The matrix of second derivatives of 21 apparent local energy minima of deca-L-alanine has been computed. The results show that all these conformations are true local energy minima and, therefore, potentially stable conformations for this peptide. Calculations of the relative statistical weights of these conformations ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Gibson KD,Scheraga HA

更新日期：1969-06-01 00:00:00

abstract：:An argument is presented in favor of the hypothesis that, bovine carboxypeptidases A and B fit by and large, the concept of homology on the levels of both amino acid sequence and three-dimensional structure. Two peptide sequences from carboxypeptidases A and B, comprising 46 amino acid residues, display structural hom...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Bradshaw RA,Neurath H,Walsh KA

更新日期：1969-06-01 00:00:00

abstract：:A muscarone-binding material has been found in Torpedo electroplax. The material behaves in several ways as one would expect of the binding component of the acetylcholine receptor, especially in its high affinity for muscarone (approximate K = 7 x 10(-6)M), acetylcholine (approximate K = 1.1 x 10(-6)M), curare, and ni...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： O'Brien RD,Gilmour LP

更新日期：1969-06-01 00:00:00

abstract：:An enzymatic activity, having the properties expected of a B-specific host-controlled modification enzyme, has been purified from an extract of Escherichia coli strain B. This activity renders the unmodified replicative form of phage fd resistant to B-specific restriction and is only present in strains carrying intact...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Kühnlein U,Linn S,Arber W

更新日期：1969-06-01 00:00:00

abstract：:For length and area, a central fact is that the value of the length of a curve or the area of a surface, as given by the Lebesgue theory, is at least as great as that given by the classical formula, whenever the latter has meaning. This is now found not to be valid in higher dimensions. We give an example of a continu...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Goffman C

更新日期：1969-05-01 00:00:00

abstract：:Two nucleases that catalyze the excision of photoproducts from UV-irradiated DNA have been extensively purified from M. luteus (M. lysodeikticus). The first enzyme, an endonuclease, has been purified 5000-fold and is free of conflicting nuclease activities. It introduces single-strand breaks into irradiated DNA but do...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Kaplan JC,Kushner SR,Grossman L

更新日期：1969-05-01 00:00:00

abstract：:We have found a soluble cyclase, using for assay radioactively marked ATP as precursor. The reaction product was isolated by thin-layer chromatography and identified by specific degradation. After homogenization, part of the activity remained in the particulate fraction but could be easily extracted. The cyclase was c...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Tao M,Lipmann F

更新日期：1969-05-01 00:00:00

abstract：:The self-adjoint algebra of operators generated by the semigroup of translation operators acting on the Hilbert space of functions supported on the half-line is studied. A real-valued index is introduced and is used to determine the spectrum of the Wiener-Hopf integral operators with distribution kernel having an almo...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Coburn LA,Douglas RG

更新日期：1969-04-01 00:00:00

abstract：:Negative cooperativity has been observed in CTP synthetase, an allosteric enzyme which contains a regulatory site. Thus, the same enzyme exhibits negative cooperativity for GTP (an effector) and glutamine (a substrate) and positive cooperativity for ATP and UTP (both substrates). In the process of the delineation of t...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Levitzki A,Koshland DE Jr

更新日期：1969-04-01 00:00:00

abstract：:The 23S twisted circular form of ColE(1) DNA has been isolated from Escherichia coli as a tightly associated DNA-protein complex with a sedimentation coefficient of approximately 24S. Treatment of this complex with pronase, trypsin, sodium dodecyl sulfate, Sarkosyl, or heat results in a conversion to a slower sediment...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Clewell DB,Helinski DR

更新日期：1969-04-01 00:00:00

abstract：:The ribonucleotide reductase system of Escherichia coli B participates in the biosynthesis of DNA by reducing ribonucleoside diphosphates to the corresponding deoxyribonucleotides. The enzyme is regulated in a complicated way by allosteric modifiers. We now find that infection of E. coli with the bacteriophage T4 resu...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Berglund O,Karlström O,Reichard P

更新日期：1969-03-01 00:00:00

abstract：:The formation of nerve-muscle junctions in monolayer cultures of embryonic muscle and spinal cord cells is described. Muscle-forming cells (myoblasts) from leg muscles of 12-day chick embryos were separated with trypsin and cultured on a collagen substrate for two days. Suspensions of ventral spinal cord cells from si...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Shimada Y,Fischman DA,Moscona AA

更新日期：1969-03-01 00:00:00

abstract：:Fibroblasts cultured from the skin of a patient with metachromatic leukodystrophy have been found to manifest the biochemical defect of this inborn error of metabolism, a deficiency of arylsulfatase A. Diseased cells had less than five per cent of normal arylsulfatase-A activity, while activities of other lysosomal en...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Porter MT,Fluharty AL,Kihara H

更新日期：1969-03-01 00:00:00

abstract：:Several tissue culture cell lines that were transformed by a tumor virus have been found to react with an agglutinin, while under identical conditions their untransformed parent cell lines did not agglutinate. Since a short treatment of the parent cell line with low concentrations of proteases exposed the same aggluti...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Burger MM

更新日期：1969-03-01 00:00:00

abstract：:Escherichia coli K12 2320(lambda)-15B has a mutation that results in ochre suppressor activity.(1) This mutation concomitantly causes a decreased growth rate in rich medium, an increased sensitivity to streptomycin,(1) and the production of some altered 30S ribosomes which are differentially sensitive to RNase.(2) The...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Gartner TK,Orias E,Lannan JE,Beeson J,Reid PJ

更新日期：1969-03-01 00:00:00

abstract：:Several authors have considered Markov processes defined by the motion of a particle on a fixed line with a random velocity(1, 6, 8, 10) or a random diffusivity.(5, 12) A "random evolution" is a natural but apparently new generalization of this notion. In this note we hope to show that this concept leads to simple and...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Griego RJ,Hersh R

更新日期：1969-02-01 00:00:00

abstract：:A specific antibody against proinsulin has been obtained by adsorbing the original anti-proinsulin guinea pig serum with a solid immunosorbent of Sephadex-insulin. The specificity of the antibody against antigenic determinants of proinsulin was established by radioimmunoassay and by passive cutaneous anaphylaxis (PCA)...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Yip CC,Logothetopoulos J

更新日期：1969-02-01 00:00:00

abstract：:There are certain genes on the sex chromosome of Drosophila for which the female contains twice as many copies as the male. Some of the genes in this group produce the same phenotype in each sex despite the dosage difference and are said, therefore, to manifest dosage compensation. The structural genes for glucose-6-p...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Seecof RL,Kaplan WD,Futch DG

更新日期：1969-02-01 00:00:00

abstract：:The operon model was proposed by Jacob and Monod in 1961 to explain the regulation of enzyme synthesis in bacteria. The model requires two genetic elements: a locus i which directs the synthesis of a repressor, and a locus called the operon which contains an operator gene and associated structural genes. The repressor...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Zubay G,Lederman M

更新日期：1969-02-01 00:00:00

abstract：:Nannofossils section sign here described are from the middle Proterozoic Paradise Creek Formation, along Paradise Creek in northwestern Queensland, Australia. These fossils, in chert blebs associated with branched stromatolites, comprise cubic colonies analogous to living Eucapsis, a member of the blue-green algal fam...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Licari GR,Cloud PE,Smith WD

更新日期：1969-01-01 00:00:00

abstract：:On the basis of earlier energy computations, the various single peptide units in proteins were designated as helix-making or helix-breaking.(1) With the use of these designations, empirical rules for distinguishing between alpha-helical and non-alpha-helical regions of proteins have been formulated. These rules includ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Kotelchuck D,Scheraga HA

更新日期：1969-01-01 00:00:00

abstract：:The circular dichroism data on 17 adenine nucleosides show that the 260- and 207-mmu absorption systems of the adenine chromophore each contain at least two electronic transitions. The CD maxima are commonly found at around 260, 220, and 200 mmu, and occasionally at 240 mmu. Solvent studies suggest that these CD bands...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Miles DW,Robins MJ,Robins RK,Eyring H

更新日期：1969-01-01 00:00:00