NifEN-B complex of Azotobacter vinelandii is fully functional in nitrogenase FeMo cofactor assembly.

abstract：:Sheep antibodies directed against an AMP-bovine serum albumin conjugate exhibit highly specific binding toward AMP. These antibodies bind to the AMP moiety of adenylylated glutamine synthetase [L-glutamate:ammonia ligase (ADP-forming), EC 6.3.1.2] from Escherichia coli and to no other antigenic determinant on the prot...

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

authors： Hohman RJ,Rhee SG,Stadtman ER

更新日期：1980-12-01 00:00:00

abstract：:Free hydrogen (H2) is a basal energy source underlying chemosynthetic activity within igneous ocean crust. In an attempt to systematically account for all H2 within young oceanic lithosphere (<10 Ma) near the Mid-Ocean Ridge (MOR), we construct a box model of this environment. Within this control volume, we assess abi...

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

authors： Worman SL,Pratson LF,Karson JA,Schlesinger WH

更新日期：2020-06-16 00:00:00

abstract：:Previous studies have shown that the oxidants Cu(++), H(2)O(2), and diamide mimic the stimulatory effect of insulin on 3-O-methylglucose transport in isolated fat cells. The present experiments were designed to determine whether sulfhydryl oxidation plays a key role in the activation of the glucose transport system. I...

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

authors： Czech MP,Lawrence JC Jr,Lynn WS

更新日期：1974-10-01 00:00:00

abstract：:Although gamma frequency oscillations are common in the brain, their functional contributions to neural computation are not understood. Here we report in vitro electrophysiological recordings to evaluate how noisy gamma frequency oscillatory input interacts with the overall activation level of a neuron to determine th...

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

authors： Markowitz DA,Collman F,Brody CD,Hopfield JJ,Tank DW

更新日期：2008-06-17 00:00:00

abstract：:Orai1 and stromal interaction molecule 1 (STIM1) mediate store-operated Ca(2+) entry (SOCE) in immune cells. STIM1, an endoplasmic reticulum (ER) Ca(2+) sensor, detects store depletion and interacts with plasma membrane (PM)-resident Orai1 channels at the ER-PM junctions. However, the molecular composition of these ju...

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

authors： Woo JS,Srikanth S,Nishi M,Ping P,Takeshima H,Gwack Y

更新日期：2016-03-08 00:00:00

abstract：:The mitochondrial enzyme glutaminase C (GAC) catalyzes the hydrolysis of glutamine to glutamate plus ammonia, a key step in the metabolism of glutamine by cancer cells. Recently, we discovered a class of allosteric inhibitors of GAC that inhibit cancer cell growth without affecting their normal cellular counterparts, ...

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

authors： Stalnecker CA,Ulrich SM,Li Y,Ramachandran S,McBrayer MK,DeBerardinis RJ,Cerione RA,Erickson JW

更新日期：2015-01-13 00:00:00

abstract：:The specific ornithine decarboxylase inhibitor alpha-difluoromethylornithine, when given to adult rats in vivo for 5 wk, resulted in a decrease in peripheral blood cell elements in normal rats and a marked suppression of marrow recovery in rats with chemotherapy-induced marrow hypoplasia. In normal rats, alpha-difluor...

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

authors： Luk GD,Sharkis SJ,Abeloff MD,McCann PP,Sjoerdsma A,Baylin SB

更新日期：1983-08-01 00:00:00

abstract：:We have found that poly(L-lysine) can be a very effective agent in preventing the growth of Ehrlich ascites tumors in mice. When given optimal doses of poly(L-lysine) (Mr 60 x 10(3)) intraperitoneally for 5 consecutive days, beginning on day 1 after inoculation with Ehrlich ascites cells. White Swiss mice show nearly ...

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

authors： Arnold LJ Jr,Dagan A,Gutheil J,Kaplan NO

更新日期：1979-07-01 00:00:00

abstract：:To evade host immune mechanisms, many bacteria secrete immunomodulatory enzymes. Streptococcus pyogenes, one of the most common human pathogens, secretes a large endoglycosidase, EndoS, which removes carbohydrates in a highly specific manner from IgG antibodies. This modification renders antibodies incapable of elicit...

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

authors： Trastoy B,Lomino JV,Pierce BG,Carter LG,Günther S,Giddens JP,Snyder GA,Weiss TM,Weng Z,Wang LX,Sundberg EJ

更新日期：2014-05-06 00:00:00

abstract：:Ischemia and reperfusion both contribute to tissue damage after myocardial infarction. Although many drugs have been shown to reduce infarct size when administered before ischemia, few have been shown to be effective when administered at reperfusion. Moreover, although it is generally accepted that a burst of reactive...

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

authors： Granville DJ,Tashakkor B,Takeuchi C,Gustafsson AB,Huang C,Sayen MR,Wentworth P Jr,Yeager M,Gottlieb RA

更新日期：2004-02-03 00:00:00

abstract：:Let G be a reductive algebraic group and let B be an affine variety with an algebraic action of G. Everything is defined over the field C of complex numbers. Consider the trivial G-vector bundle B x S = S over B where S is a G-module. From the endomorphism ring R of the G-vector bundle S a construction of G-vector bun...

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

authors： Masuda M,Petrie T

更新日期：1991-10-15 00:00:00

abstract：:The structure of respiratory cytochrome c551 of Pseudomonas aeruginosa, with 82 amino acids, has been solved by x-ray analysis and refined to a crystallographic R factor of 16.2%. It has the same basic folding pattern and hydrophobic heme environment as cytochromes c, c2, and c550, except for a large deletion at the b...

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

authors： Almassy RJ,Dickerson RE

更新日期：1978-06-01 00:00:00

abstract：:Using a water-based prebiotic model of sugar synthesis involving glycolaldehyde self-condensation, we demonstrate that homochiral L-dipeptide catalysts lead to the stereospecific syntheses of tetroses. The asymmetric effect is largest for erythrose, which may reach a D-enantiomeric excess of >80% with L-Val-L-Val cata...

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

authors： Weber AL,Pizzarello S

更新日期：2006-08-22 00:00:00

abstract：:Sodium/hydrogen exchangers (NHEs) are ubiquitous ion transporters that serve multiple cell functions. We have studied two mammalian isoforms, NHE1 (ubiquitous) and NHE3 (epithelial-specific), by measuring extracellular proton (H+) gradients during whole-cell patch clamp with perfusion of the cell interior. Maximal Na(...

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

authors： Fuster D,Moe OW,Hilgemann DW

更新日期：2004-07-13 00:00:00

abstract：:In spite of the diversity of possible biological forms observed in nature, a limited range of morphospace is frequently occupied for a given trait. Several mechanisms have been proposed to explain this bias in the distribution of phenotypes including selection, drift, and developmental constraints. Despite extensive w...

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

authors： Malagón JN,Ahuja A,Sivapatham G,Hung J,Lee J,Muñoz-Gómez SA,Atallah J,Singh RS,Larsen E

更新日期：2014-09-30 00:00:00

abstract：:Previous studies have shown that Arthrobacter pyridinolis can transport D-fructose or L-rhamnose using either a phosphoenolpyruvate:hexose phosphotransferase (phosphoenolpyruvate:protein phosphotransferase, EC 2.7.3.9) system or a respiration-coupled transport system which requires the presence of exogenous L-malate. ...

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

authors： Wolfson EB,Krulwich TA

更新日期：1974-05-01 00:00:00

abstract：:Although prairie voles (Microtus ochrogaster) are socially monogamous, males vary in both sexual and spatial fidelity. Most males form pairbonds, cohabit with one female, and defend territories. Wandering males, in contrast, have expansive home ranges that overlap many males and females. In the laboratory, pairing is ...

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

authors： Ophir AG,Wolff JO,Phelps SM

更新日期：2008-01-29 00:00:00

abstract：:Mixed-metal oxides play a very important role in many areas of chemistry, physics, materials science, and geochemistry. Recently, there has been a strong interest in understanding phenomena associated with the deposition of oxide nanoparticles on the surface of a second (host) oxide. Here, scanning tunneling microscop...

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

authors： Park JB,Graciani J,Evans J,Stacchiola D,Ma S,Liu P,Nambu A,Sanz JF,Hrbek J,Rodriguez JA

更新日期：2009-03-31 00:00:00

abstract：:Hypnotic analgesia in some respects resembles opiate analgesia. We tested the hypothesis that some features of hypnotic analgesia are mediated through neuronal pathways activating specific opiate receptors in brain. The opiate antagonist naloxone had no effect on hypnotic analgesia in three subjects. Thus, the hypothe...

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

authors： Goldstein A,Hilgard ER

更新日期：1975-06-01 00:00:00

abstract：:To probe the structure of the gamma heavy chain of membrane IgG and the mRNA and gene segments that encode it, we have analyzed cDNA clones derived from a gamma 1 membrane RNA of B lymphoma 2PK-3. The nucleotide sequence of the clones indicated that membrane gamma 1 chains bear a COOH-terminal 71-residue segment that ...

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

authors： Tyler BM,Cowman AF,Gerondakis SD,Adams JM,Bernard O

更新日期：1982-03-01 00:00:00

abstract：:Myelin basic proteins (MBP) are major constituents of the myelin sheath of oligodendrocytes and Schwann cells in the central nervous system and the peripheral nervous system, respectively. We previously showed that MBP-related transcripts are present in the bone marrow and the immune system. These mRNAs are transcribe...

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

authors： Marty MC,Alliot F,Rutin J,Fritz R,Trisler D,Pessac B

更新日期：2002-06-25 00:00:00

abstract：:The principal axes of inertia are eigenvectors that can be calculated for any rigid body. We report studies of the position of the principal axes in crystallographically solved protein molecules. We find with high frequency that at least one principal axis penetrates the surface of the respective protein in a region u...

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

authors： Foote J,Raman A

更新日期：2000-02-01 00:00:00

abstract：:The kinetics of charge transfer depend crucially on the dielectric reorganization of the medium. In enzymatic reactions that involve charge transfer, atomic dielectric response of the active site and of its surroundings determines the efficiency of the protein as a catalyst. We report direct spectroscopic measurements...

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

authors： Mertz EL,Krishtalik LI

更新日期：2000-02-29 00:00:00

abstract：:Sequence polymorphism of class II major histocompatibility complex-encoded molecules (Ia) not only accounts for the allelic variability in Ia structure relevant to T-lymphocyte responses but also seems to result in differential quantitative expression of particular Ia heterodimers. The contributions of different allel...

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

authors： Braunstein NS,Germain RN

更新日期：1987-05-01 00:00:00

abstract：:Establishment of functional synaptic connections in a selective manner is essential for nervous system operation. In mammalian retinas, rod and cone photoreceptors form selective synaptic connections with different classes of bipolar cells (BCs) to propagate light signals. While there has been progress in elucidating ...

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

authors： Cao Y,Wang Y,Dunn HA,Orlandi C,Shultz N,Kamasawa N,Fitzpatrick D,Li W,Zeitz C,Hauswirth W,Martemyanov KA

更新日期：2020-09-22 00:00:00

abstract：:We show that epidermal growth factor (EGF) receptor can be transferred in a biologically active orientation from donor hepatic membranes to recipient receptorless fibroblast cells. The recipient cells (NR-6) normally lack EGF receptors and are biologically unresponsive to EGF. The transfer of receptors from donor plas...

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

authors： Bishayee S,Feinman J,Pittenger M,Michael H,Das M

更新日期：1982-03-01 00:00:00

abstract：:The world's oceans are undergoing profound changes as a result of human activities. However, the consequences of escalating human impacts on marine mammal biodiversity remain poorly understood. The International Union for the Conservation of Nature (IUCN) identifies 25% of marine mammals as at risk of extinction, but ...

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

authors： Davidson AD,Boyer AG,Kim H,Pompa-Mansilla S,Hamilton MJ,Costa DP,Ceballos G,Brown JH

更新日期：2012-02-28 00:00:00

abstract：:Glial fibrillary acidic protein (GFAP) is an intermediate-filament (IF) protein that is highly specific for cells of astroglial lineage, although its tissue-specific role is speculative. Determination of the primary structure of this protein should be of importance for understanding the functional role it plays in ast...

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

authors： Reeves SA,Helman LJ,Allison A,Israel MA

更新日期：1989-07-01 00:00:00

abstract：:Recently it has become apparent that N = 2 supersymmetric quantum field theory has something to do with cluster algebras. I review one aspect of the connection: supersymmetric quantum field theories have associated hyperkähler moduli spaces, and these moduli spaces carry a structure that looks like an extension of the...

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

authors： Neitzke A

更新日期：2014-07-08 00:00:00

abstract：:Pancreatic and gastrointestinal D cells were examined by immunocytochemistry using antisera against somatostatin-28 (SS28) and its NH2-terminal fragment SS28-(1-12), followed by the staphylococcal protein A-gold (pAg) complex. In pancreatic and gastric D cells incubated with antiserum against SS28-(1-12) the gold part...

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

authors： Ravazzola M,Benoit R,Ling N,Guillemin R,Orci L

更新日期：1983-01-01 00:00:00