Genome sequencing of environmental Escherichia coli expands understanding of the ecology and speciation of the model bacterial species.

abstract：:Among the earliest and most important stages during tumorigenesis is the activation of the angiogenic process, an event that is termed the "switch to the angiogenic phenotype." We have developed an in vivo system that can reliably recapitulate the stages in tumor development that represent this transition. Using this ...

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

authors： Fang J,Shing Y,Wiederschain D,Yan L,Butterfield C,Jackson G,Harper J,Tamvakopoulos G,Moses MA

更新日期：2000-04-11 00:00:00

abstract：:The initial electron transfer steps in the photosynthetic reaction center of the purple bacterium Rhodobacter sphaeroides have been investigated by femtosecond time-resolved spectroscopy. The experimental data taken at various wavelengths demonstrate the existence of at least four intermediate states within the first ...

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

authors： Holzapfel W,Finkele U,Kaiser W,Oesterhelt D,Scheer H,Stilz HU,Zinth W

更新日期：1990-07-01 00:00:00

abstract：:In movies or on TV, a wheel can seem to rotate backwards, due to the temporal subsampling inherent in the recording process (the wagon wheel illusion). Surprisingly, this effect has also been reported under continuous light, suggesting that our visual system, too, might sample motion in discrete "snapshots." Recently,...

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

authors： VanRullen R,Reddy L,Koch C

更新日期：2005-04-05 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 covalent linkage of supramolecular monomers provides a powerful strategy for constructing dynamic polymeric materials whose properties can be readily tuned either by the selection of monomers or the choice of functional linkers. In this strategy, the stabilities of the supramolecular monomers and the reactions use...

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

authors： Zhang M,Li S,Yan X,Zhou Z,Saha ML,Wang YC,Stang PJ

更新日期：2016-10-04 00:00:00

abstract：:Methods to accurately predict potential drug target mutations in response to early-stage leads could drive the design of more resilient first generation drug candidates. In this study, a structure-based protein design algorithm (K* in the OSPREY suite) was used to prospectively identify single-nucleotide polymorphisms...

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

authors： Reeve SM,Gainza P,Frey KM,Georgiev I,Donald BR,Anderson AC

更新日期：2015-01-20 00:00:00

abstract：:A procedure using ion exchange chromatography has been developed to detect alterations in a polysaccharide produced by Neurospora crassa. The polysaccharide, isolated from medium that has supported the growth of a culture, is highly responsive to the 3-methyl-2-benzothiazolinone hydrazone assay, indicating a high hexo...

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

authors： Springer WD,Srb AM

更新日期：1978-03-01 00:00:00

abstract：:We have examined the 270 MHz nuclear magnetic resonance spectrum and relaxation kinetic behavior of tRNA2Glu (E. coli) in the absence of Mg++, a condition which produces an inactive form of this tRNA. The results show that the denatured form has about five fewer proton resonances in the region from -12 to -15 ppm. Rel...

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

authors： Bina-Stein M,Crothers DM,Hilbers CW,Shulman RG

更新日期：1976-07-01 00:00:00

abstract：:A series of pyrimidine nucleoside analogues containing [2',5'-bis-O-(tert-butyldimethylsilyl)-3'-spiro-5''-(4''-amino- 1'',2''-oxathiole-2'',2''-dioxide)]-beta-D-ribofuranose as the pentose were found to inhibit human immunodeficiency virus type 1 [HIV-1(IIIB)] replication at a concentration of 0.06-0.8 microM but wer...

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

authors： Balzarini J,Pérez-Pérez MJ,San-Félix A,Schols D,Perno CF,Vandamme AM,Camarasa MJ,De Clercq E

更新日期：1992-05-15 00:00:00

abstract：:Gaseous molecular ions containing argon and perchlorethylene, Ar(n)(C(2)Cl(4))(m) (+) in which n >/= 1-29 and m >/= 1-4, are produced by electron bombardment of van der Waals clusters formed by expanding an Ar/C(2)Cl(4) mixture through a supersonic nozzle. Previous attempts to observe such ions in a high-pressure mass...

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

authors： Buelow SJ,Worsnop DR,Herschbach DR

更新日期：1981-12-01 00:00:00

abstract：:The notion that tRNA and 5S rRNA interact through evolutionarily conserved complementary sequences has been tested by nucleolytic modification of the 5S rRNA, using the modified rRNA to reconstitute the large ribosomal subunit, and assaying for poly(uridylic acid)-directed polyphenylalanine synthesis. The 5S rRNA sequ...

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

authors： Pace B,Matthews EA,Johnson KD,Cantor CR,Pace NR

更新日期：1982-01-01 00:00:00

abstract：:Salmonella enterica serovar Typhi can colonize the gallbladder and persist in an asymptomatic carrier state that is frequently associated with the presence of gallstones. We have shown that salmonellae form bile-mediated biofilms on human gallstones and cholesterol-coated surfaces in vitro. Here, we test the hypothesi...

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

authors： Crawford RW,Rosales-Reyes R,Ramírez-Aguilar Mde L,Chapa-Azuela O,Alpuche-Aranda C,Gunn JS

更新日期：2010-03-02 00:00:00

abstract：:Antigen receptor gene assembly is regulated by transcriptional promoters and enhancers, which control the accessibility of gene segments to a lymphocyte-specific V(D)J recombinase. However, it remained unclear whether accessibility depends on the process of transcription itself or chromatin modifications that accompan...

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

authors： Sikes ML,Meade A,Tripathi R,Krangel MS,Oltz EM

更新日期：2002-09-17 00:00:00

abstract：:Microstructural, δ(13)C isotope and C/N ratio investigations were conducted on excavated material from the black Younger Dryas boundary in Lommel, Belgium, aiming for a characterisation of the carbon content and structures. Cubic diamond nanoparticles are found in large numbers. The larger ones with diameters around o...

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

authors： Tian H,Schryvers D,Claeys P

更新日期：2011-01-04 00:00:00

abstract：:Rhizobia colonize their legume hosts by different modes of entry while initiating symbiotic nitrogen fixation. Most legumes are invaded via growing root hairs by the root hair-curl mechanism, which involves epidermal cell responses. However, invasion of a number of tropical legumes happens through fissures at lateral ...

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

authors： Goormachtig S,Capoen W,James EK,Holsters M

更新日期：2004-04-20 00:00:00

abstract：:A lysine-to-arginine substitution at amino acid 65 (K65R) in human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) is associated with resistance to 2',3'-dideoxycytidine (ddC), 2',3'-dideoxyinosine (ddI), and the (-) enantiomer of 2',3'-dideoxy-3'-thiacytidine (3TC). To further characterize the molecu...

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

authors： Gu Z,Arts EJ,Parniak MA,Wainberg MA

更新日期：1995-03-28 00:00:00

abstract：:Transport affects climate directly and indirectly through mechanisms that cause both warming and cooling of climate, and the effects operate on very different timescales. We calculate climate responses in terms of global mean temperature and find large differences between the transport sectors with respect to the size...

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

authors： Berntsen T,Fuglestvedt J

更新日期：2008-12-09 00:00:00

abstract：:Regulatory T cells (Treg) comprise multiple subsets and are important in controlling immunity and inflammation. However, the induction and mode of action of the various distinct Treg subsets remain ill defined, particularly in humans. Here, we describe a human CD8+ lymphocyte activation gene-3 (LAG-3)+CD25+FoxP3+ Treg...

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

authors： Joosten SA,van Meijgaarden KE,Savage ND,de Boer T,Triebel F,van der Wal A,de Heer E,Klein MR,Geluk A,Ottenhoff TH

更新日期：2007-05-08 00:00:00

abstract：:A somatic mutation in the X linked PIGA gene is responsible for the deficiency of glycosyl phosphatidylinositol (GPI)-anchored proteins on blood cells from patients with paroxysmal nocturnal hemoglobinuria. No inherited form of GPI-anchor deficiency has been described. Because conventional Piga gene knockout is associ...

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

authors： Keller P,Tremml G,Rosti V,Bessler M

更新日期：1999-06-22 00:00:00

abstract：:Pancreatic cancer is one of the most deadly cancers affecting the Western world. Because the disease is highly metastatic and difficult to diagnosis until late stages, the 5-y survival rate is around 5%. The identification of molecular cancer drivers is critical for furthering our understanding of the disease and deve...

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

authors： Mann KM,Ward JM,Yew CC,Kovochich A,Dawson DW,Black MA,Brett BT,Sheetz TE,Dupuy AJ,Australian Pancreatic Cancer Genome Initiative.,Chang DK,Biankin AV,Waddell N,Kassahn KS,Grimmond SM,Rust AG,Adams DJ,Jenkins NA,Copela

更新日期：2012-04-17 00:00:00

abstract：:By using harmonic radar, we report the complete flight paths of displaced bees. Test bees forage at a feeder or are recruited by a waggle dance indicating the feeder. The flights are recorded after the bees are captured when leaving the hive or the feeder and are released at an unexpected release site. A sequence of b...

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

authors： Menzel R,Greggers U,Smith A,Berger S,Brandt R,Brunke S,Bundrock G,Hülse S,Plümpe T,Schaupp F,Schüttler E,Stach S,Stindt J,Stollhoff N,Watzl S

更新日期：2005-02-22 00:00:00

abstract：:Ras is a guanine nucleotide-binding protein that cycles between inactive GDP-bound and active GTP-bound states to regulate a diverse array of cellular processes, including cell growth, apoptosis, and differentiation. The guanine nucleotide-bound state of Ras is tightly maintained by regulatory factors to promote regul...

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

authors： Williams JG,Pappu K,Campbell SL

更新日期：2003-05-27 00:00:00

abstract：:The formation of amyloid-like aggregates by expanded polyglutamine (polyGln) sequences is suspected to play a critical role in the neuropathology of Huntington's disease and other expanded CAG-repeat diseases. To probe the folding of the polyGln sequence in the aggregate, we replaced Gln-Gln pairs at different sequenc...

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

authors： Thakur AK,Wetzel R

更新日期：2002-12-24 00:00:00

abstract：:Myxococcus xanthus is a Gram-negative bacterium that aggregates to form fruiting bodies when nutrients are limiting. Previous studies showed that the frz mutants that are defective in chemotaxis exhibited irregular and infrequent patterns of cellular reversal. In contrast, wild-type cells, when examined individually, ...

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

authors： Shi W,Ngok FK,Zusman DR

更新日期：1996-04-30 00:00:00

abstract：:We have shown that 3-nitropropionate, an isoelectronic analogue of succinate, is a suicide inactivator of succinate dehydrogenase [succinate:(acceptor) oxidoreductase, EC 1.3.99.1] as follows. (i) When rat liver mitochondria oxidize succinate in the presence of 3-nitropropionate carbanion, the rate of O(2) consumption...

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

authors： Alston TA,Mela L,Bright HJ

更新日期：1977-09-01 00:00:00

abstract：:Temporal patterning of biological variables, in the form of oscillations and rhythms on many time scales, is ubiquitous. Altering the temporal pattern of an input variable greatly affects the output of many biological processes. We develop here a conceptual framework for a quantitative understanding of such pattern de...

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

authors： Brezina V,Orekhova IV,Weiss KR

更新日期：1997-09-16 00:00:00

abstract：:Skeletal muscle L-type Ca2+ channels respond to trains of brief depolarizations with a strong shift of the voltage dependence of channel activation toward more negative membrane potentials and slowing of channel deactivation. Increased Ca2+ entry resulting from this potentiation of channel activity may increase contra...

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

authors： Johnson BD,Scheuer T,Catterall WA

更新日期：1994-11-22 00:00:00

abstract：:Mouse lymphocytic cells of the established line GF-14 were allowed to accumulate intracellular 3H-labeled aminoisobutyric acid (AIB), frozen, and stored over liquid N2. After internal radiation had reduced survival to 1 in 10(4), survivors were plated and tested for their ability to transport AIB. Out of 200 clones te...

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

authors： Finkelstein MC,Slayman CW,Adelberg EA

更新日期：1977-10-01 00:00:00

abstract：:Sex determination in mammals is governed by antagonistic interactions of two genetic pathways, imbalance in which may lead to disorders/differences of sex development (DSD) in human. Among 46,XX individuals with testicular DSD (TDSD) or ovotesticular DSD (OTDSD), testicular tissue is present in the gonad. Although the...

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

authors： Eozenou C,Gonen N,Touzon MS,Jorgensen A,Yatsenko SA,Fusee L,Kamel AK,Gellen B,Guercio G,Singh P,Witchel S,Berman AJ,Mainpal R,Totonchi M,Mohseni Meybodi A,Askari M,Merel-Chali T,Bignon-Topalovic J,Migale R,Costanzo

更新日期：2020-06-16 00:00:00

abstract：:Euplotes raikovi of the wild-type strain 13 was found to be heterozygous (mat-1/mat-2) for the genetic locus mat, which is supposed to control the mating-type specificity of freely released mating pheromones ("euplomones"), and capable of yielding the two types of corresponding homozygotes (mat-1/mat-1, mat-2/mat-2). ...

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

authors： Luporini P,Raffioni S,Concetti A,Miceli C

更新日期：1986-05-01 00:00:00