Abstract:
:Vibrio cholerae serogroup O139 emerged on the Indian subcontinent in October 1992 to become the first non-O1 V. cholerae serogroup documented to cause epidemic cholera. Although related to V. cholerae El Tor O1 strains, O139 strains have unique surface structures that include a capsular surface layer and lipopolysaccharide (LPS). Immunoblot analysis of either whole-cell lysates or LPS preparations revealed three electrophoretic forms of the O139 antigen: two slowly migrating forms and one rapidly migrating form that appeared identical to O139 LPS. All three forms of the antigen shared an epitope defined by an O139-specific monoclonal antibody. A serum-sensitive nonencapsulated mutant was isolated that lacks only the slow migrating forms. The slow migrating forms did not stain with silver whereas the rapidly migrating form did, suggesting that the former might constitute highly polymerized O-antigen side-chain molecules that were not covalently bound to core polysaccharide and lipid A (an "O-antigen capsule"). A single transposon insertion resulted in the loss of immunoreactivity of both the LPS and the O-antigen capsule, implying that there are genes common to the biosynthesis of both these macromolecules. The O139 LPS and O-antigen capsule were both important for colonization of the small intestine of the newborn mouse and for serum resistance, demonstrating that both of these forms of the O139 serogroup antigen are virulence factors.
journal_name
Proc Natl Acad Sci U S Aauthors
Waldor MK,Colwell R,Mekalanos JJdoi
10.1073/pnas.91.24.11388subject
Has Abstractpub_date
1994-11-22 00:00:00pages
11388-92issue
24eissn
0027-8424issn
1091-6490journal_volume
91pub_type
杂志文章abstract::Resequencing or reference-based assemblies reveal large parts of the small-scale sequence variation. However, they typically fail to separate such local variation into colinear and rearranged variation, because they usually do not recover the complement of large-scale rearrangements, including transpositions and inver...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1607532113
更新日期:2016-07-12 00:00:00
abstract::The growth of 3T3 and SV101 3T3 cells in a lipid-depleted medium is enhanced by the addition of biotin or some fatty acids. The extent of enhancement depends on the fatty acid(s) supplied. The presence of linoleate is unique, since it induces a morphological alteration in 3T3 cells resulting in a cell similar to an SV...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.71.8.3115
更新日期:1974-08-01 00:00:00
abstract::Recent evidence implicates dysregulation of metabotropic glutamatergic receptor 5 (mGluR5) in pathophysiology of PTSD and suicidality. Using positron emission tomography and [18F]FPEB, we quantified mGluR5 availability in vivo in individuals with PTSD (n = 29) and MDD (n = 29) as a function of suicidal ideation (SI) t...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1818871116
更新日期:2019-06-04 00:00:00
abstract::Transferrin, a nonheme iron-binding protein, is polymorphic in most vertebrate species that have been examined. In pigeons, it is controlled by an autosomal gene, with two known codominant alleles, Tf(A) and Tf(B). The two alleles are found in nearly equal frequencies and the three genotypes are at Hardy-Weinberg equi...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.69.2.326
更新日期:1972-02-01 00:00:00
abstract::The presynaptic plasma membrane protein SNAP-25 (synaptosome-associated protein of 25 kDa) has been implicated as one of several neural-specific components that direct constitutive fusion mechanisms to the regulated vesicle trafficking and exocytosis of neurotransmitter release. There exist two alternatively spliced i...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.92.5.1510
更新日期:1995-02-28 00:00:00
abstract::Galanin is a neuropeptide with a wide variety of biological functions, including that of a strong endogenous anticonvulsant. No nonpeptide ligands, capable of activating galanin receptors, are available today. Based on known pharmacophores of galanin, a combinatorial library was designed, synthesized, and screened at ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.102163499
更新日期:2002-05-14 00:00:00
abstract::Tephritid fruit flies belonging to the Rhagoletis pomonella sibling species complex are controversial because they have been proposed to diverge in sympatry (in the absence of geographic isolation) by shifting and adapting to new host plants. Here, we report evidence suggesting a surprising source of genetic variation...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1730757100
更新日期:2003-09-02 00:00:00
abstract::The search for ever deeper relationships among the World's languages is bedeviled by the fact that most words evolve too rapidly to preserve evidence of their ancestry beyond 5,000 to 9,000 y. On the other hand, quantitative modeling indicates that some "ultraconserved" words exist that might be used to find evidence ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 历史文章,杂志文章
doi:10.1073/pnas.1218726110
更新日期:2013-05-21 00:00:00
abstract::We discuss the generic time behavior of reaction-diffusion processes capable of modeling various types of biological transport processes, such as ligand migration in proteins and gating fluctuations in ion channel proteins. The main observable in these two cases, the fraction of unbound ligands and the probability of ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.88.15.6750
更新日期:1991-08-01 00:00:00
abstract::After treatment with nitrite, Japanese soy sauce was strongly mutagenic to Salmonella typhimurium TA100 without S9 mixture. Two precursors of the mutagen were isolated from Japanese soy sauce, and these were identified as (-)-(1S,3S)-1-methyl-1,2,3,4-tetrahydro-beta-carboline-3-carboxylic acid [(-)-(1S,3S)-MTCA] and i...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.80.10.2912
更新日期:1983-05-01 00:00:00
abstract::F(o)F(1)-ATP synthase manufactures the energy "currency," ATP, of living cells. The soluble F(1) portion, called F(1)-ATPase, can act as a rotary motor, with ATP binding, hydrolysis, and product release, inducing a torque on the gamma-subunit. A coarse-grained plastic network model is used to show at a residue level o...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0708746105
更新日期:2008-01-29 00:00:00
abstract::In plants, the AUXIN RESPONSE FACTOR (ARF) transcription factor family regulates gene expression in response to auxin. In the absence of auxin, ARF transcription factors are repressed by interaction with AUXIN/INDOLE 3-ACETIC ACID (Aux/IAA) proteins. Although the C termini of ARF and Aux/IAA proteins facilitate their ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1400074111
更新日期:2014-04-08 00:00:00
abstract::Insulin provides a classical model of a globular protein, yet how the hormone changes conformation to engage its receptor has long been enigmatic. Interest has focused on the C-terminal B-chain segment, critical for protective self-assembly in β cells and receptor binding at target tissues. Insight may be obtained fro...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1412897111
更新日期:2014-08-19 00:00:00
abstract::O(6)-methylguanine (O(6)meG) and related modifications of guanine in double-stranded DNA are functionally severe lesions that can be produced by many alkylating agents, including N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), a potent carcinogen. O(6)meG is repaired through its demethylation by the O(6)-alkylguanine-DNA...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0812316106
更新日期:2009-02-17 00:00:00
abstract::The integrity of cell membranes is maintained by a balance between the amount of cholesterol and the amounts of unsaturated and saturated fatty acids in phospholipids. This balance is maintained by membrane-bound transcription factors called sterol regulatory element-binding proteins (SREBPs) that activate genes encod...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章,评审
doi:10.1073/pnas.96.20.11041
更新日期:1999-09-28 00:00:00
abstract::The proteasome is responsible for degradation of substrates of the ubiquitin pathway. 20S proteasomes are cylindrical particles with subunits arranged in a stack of four heptameric rings. The outer rings are composed of alpha subunits, and the inner rings are composed of beta subunits. A well-characterized archaeal pr...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.94.14.7156
更新日期:1997-07-08 00:00:00
abstract::Ferritin has a protein shell of 5 X 10(6) Da consisting of 24 subunits of two types, a heavier (H) chain of 21,000 Da and a lighter (L) chain of 19,000 Da. A cDNA clone of the messenger for the L subunit has been isolated from a human monocyte-like leukemia cell line. The clone contains an open reading frame of 522 nu...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.82.10.3139
更新日期:1985-05-01 00:00:00
abstract::Single cortical neurons in the mammalian brain receive signals arising from multiple sensory input channels. Dendritic integration of these afferent signals is critical in determining the amplitude and time course of the neurons' output signals. As of yet, little is known about the spatial and temporal organization of...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1112355108
更新日期:2011-09-13 00:00:00
abstract::We have used a membrane-leak mass spectrometer to follow the time courses of H2 evolution and substrate reduction by nitrogenase [reduced ferredoxin:dinitrogen oxidoreductase (ATP-hydrolyzing), EC 1.18.6.1]. In the absence of added substrates, dinitrogenase passes all of its electrons to protons to form H2, but when a...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.85.24.9446
更新日期:1988-12-01 00:00:00
abstract::Ionizing radiation (IR) induces a variety of DNA lesions among which DNA double-strand breaks (DSBs) are the biologically most significant. It is currently unclear if DSB repair is equally efficient after low and high doses. Here, we use gamma-H2AX, phospho-ATM (pATM), and 53BP1 foci analysis to monitor DSB repair. We...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1002213107
更新日期:2010-08-10 00:00:00
abstract::Lung adenocarcinomas harboring activating mutations in the epidermal growth factor receptor (EGFR) represent a common molecular subset of non-small cell lung cancer (NSCLC) cases. EGFR mutations predict sensitivity to EGFR tyrosine kinase inhibitors (TKIs) and thus represent a dependency in NSCLCs harboring these alte...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1412228112
更新日期:2014-12-30 00:00:00
abstract::The electrical block to fertilization of sea urchin eggs can be overcome by very brief periods of inside-negative egg membrane potential. Lytechinus pictus eggs whose membrane potentials have been clamped at +15 mV cannot be fertilized. If the membrane potential is repolarized to inside-negative voltages for a brief i...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.81.5.1436
更新日期:1984-03-01 00:00:00
abstract::Converging TGF-beta and insulin-like neuroendocrine signaling pathways regulate whether Caenorhabditis elegans develops reproductively or arrests at the dauer larval stage. We examined whether neurotransmitters act in the dauer entry or recovery pathways. Muscarinic agonists promote recovery from dauer arrest induced ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.97.1.460
更新日期:2000-01-04 00:00:00
abstract::Ultrastructural cytochemistry of natural killer cells enriched by Percoll gradient centrifugation showed them to possess arylsulfatase (aryl-sulfate sulfohydrolase, EC 3.1.6.1). The enzyme was located in vesicles, granules, and the parallel tubular arrays, organelles characteristic for cytotoxic lymphocytes. Biochemic...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.80.22.6977
更新日期:1983-11-01 00:00:00
abstract::The role of protein farnesylation in lamin A biogenesis and the pathogenesis of progeria has been studied in considerable detail, but the importance of farnesylation for the B-type lamins, lamin B1 and lamin B2, has received little attention. Lamins B1 and B2 are expressed in nearly every cell type from the earliest s...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1303916110
更新日期:2013-05-21 00:00:00
abstract::The poly(A) site of bovine prolactin (bPRL) mRNA was examined by phased priming of cDNA synthesis with oligodeoxynucleotides of the general sequence d(pT8-N-N'). The existence of multiple poly(A)-adjacent sequences in bPRL mRNA was indicated by the production of specific chain-termination fragments with at least three...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.79.2.223
更新日期:1982-01-01 00:00:00
abstract::Heterosis is widely applied in agriculture; however, the underlying molecular mechanisms for superior performance are not well understood. Ethylene biosynthesis and signaling genes are shown to be down-regulated in Arabidopsis interspecific hybrids. Ethylene is a plant hormone that promotes fruit ripening and maturati...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1722068115
更新日期:2018-05-22 00:00:00
abstract::AvrXa7 is a member of the avrBs3 avirulence gene family, which encodes proteins targeted to plant cells by a type III secretion apparatus. AvrXa7, the product of avrXa7, is also a virulence factor in strain PXO86 of Xanthomonas oryzae pv. oryzae. Avirulence and virulence specificities are associated with the central r...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.170286897
更新日期:2000-08-15 00:00:00
abstract::Relaxin is a member of the insulin family of polypeptides that is best known as a reproductive hormone. In an effort to elucidate the mechanism of action of relaxin we previously localized the specific binding sites of a 32P-labeled relaxin in the rat uterus and brain. These studies suggested that, in addition to its ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.89.6.2384
更新日期:1992-03-15 00:00:00
abstract::The β-1,3-glucan chrysolaminarin is the main storage polysaccharide of diatoms. In contrast to plants and green algae, diatoms and most other algal groups do not accumulate storage polysaccharides in their plastids. The diatom Phaeodactylum tricornutum possesses only a single gene encoding a putative β-1,3-glucan synt...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1719274115
更新日期:2018-05-01 00:00:00