Abstract:
:A reaction cycle for electron-transportdriven proton pumps is proposed. It includes two distinct conformational states of the pump protein in which the primary electron acceptor has different reduction potentials. This has as an unavoidable consequence that the steady-state rate equation for the catalytic reaction driving the pump is nonhyperbolic. The model can be used to simulate experimental results for the kinetics of cytochrome oxidase (EC 1.9.3.1) in a wide range of experimental conditions (ionic strength, pH, temperature). It is thus not necessary to invoke more than one binding site for cytochrome c to account for the biphasic response of the oxidase activity to the concentration of this substrate.
journal_name
Proc Natl Acad Sci U S Aauthors
Brzezinski P,Malmström BGdoi
10.1073/pnas.83.12.4282subject
Has Abstractpub_date
1986-06-01 00:00:00pages
4282-6issue
12eissn
0027-8424issn
1091-6490journal_volume
83pub_type
杂志文章abstract::The Ly-6 locus encodes several cell surface proteins whose functions are unknown. Although it is hypothesized that these proteins may be receptors, there is no direct evidence that they bind a ligand. Herein we present evidence that Ly-6A.2, a Ly-6 protein expressed on T lymphocytes, binds a ligand expressed on normal...
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.92.10.4294
更新日期:1995-05-09 00:00:00
abstract::Barth, Larsen, and others showed that complex submanifolds of complex projective space, CP(N), of small codimension strongly resemble CP(N) both homotopically and cohomologically. These results are generalized to yield analogous results for complex subspaces of arbitrary homogeneous complex manifolds. One very special...
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.74.4.1332
更新日期:1977-04-01 00:00:00
abstract::Antimicrobial peptides, in particular α-defensins expressed by Paneth cells, control microbiota composition and play a key role in intestinal barrier function and homeostasis. Dynamic conditions in the local microenvironment, such as pH and redox potential, significantly affect the antimicrobial spectrum. In contrast ...
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.1817376116
更新日期:2019-02-26 00:00:00
abstract::Current evidence suggests that the length of poly(A) tails of bacterial mRNAs result from a competition between poly(A) polymerase and exoribonucleases that attack the 3' ends of RNAs. Here, we show that host factor Hfq is also involved in poly(A) tail metabolism. Inactivation of the hfq gene reduces the length of pol...
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.040549897
更新日期:2000-02-15 00:00:00
abstract::Pseudomonas aeruginosa infects every type of host that has been examined by deploying multiple virulence factors. Previous studies of virulence regulation have largely focused on chemical cues, but P. aeruginosa may also respond to mechanical cues. Using a rapid imaging-based virulence assay, we demonstrate that P. ae...
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.1415712111
更新日期:2014-11-25 00:00:00
abstract::In this study we sought to better understand the role of the glycoprotein quality control machinery in the assembly of MHC class I molecules with high-affinity peptides. The lectin-like chaperone calreticulin (CRT) and the thiol oxidoreductase ERp57 participate in the final step of this process as part of the peptide-...
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.1102524108
更新日期:2011-03-22 00:00:00
abstract::We show that a drop of liquid a few hundred microns in diameter placed under a solid, elastic, thin film (∼10 μm thick) causes it to bulge by tens of microns. The deformed shape is governed by equilibrium of tensions exerted by the various interfaces and the solid film, a form of Neumann's triangle. Unlike Young's equ...
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.1304587110
更新日期:2013-06-25 00:00:00
abstract::Tandem gene duplication is an important mutational process in evolutionary adaptation and human disease. Hypothetically, two tandem gene copies should produce twice the output of a single gene, but this expectation has not been rigorously investigated. Here, we show that tandem duplication often results in more than d...
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.1605886113
更新日期:2016-05-24 00:00:00
abstract::Predicting the timing of upcoming events is critical for successful interaction in a dynamic world, and is recognized as a key computation for attentional orienting. Temporal predictions can be formed when recent events define a rhythmic structure, as well as in aperiodic streams or even in isolation, when a specified...
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.1810596115
更新日期:2018-11-27 00:00:00
abstract::Linkage disequilibrium between polymorphisms in a natural population may result from various evolutionary forces, including random genetic drift due to sampling of gametes during reproduction, restricted migration between subpopulations in a subdivided population, or epistatic selection. In this report, we present evi...
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.92.20.9047
更新日期:1995-09-26 00:00:00
abstract::Single-copy transgenes in Caenorhabditis elegans can be subjected to a potent, irreversible silencing process termed small RNA-induced epigenetic silencing (RNAe). RNAe is promoted by the Piwi Argonaute protein PRG-1 and associated Piwi-interacting RNAs (piRNAs), as well as by proteins that promote and respond to seco...
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.1501979112
更新日期:2015-05-19 00:00:00
abstract::Specific viral transformation rather than cell selection can explain the previously observed increase in the proportion of type III procollagen compared to type I procollagen in BALB 3T3 cells transformed by Kirsten murine sarcoma virus (Ki-MSV). Two subclones of BALB 3T3 A31 were productively infected with with a tem...
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.78.10.6028
更新日期:1981-10-01 00:00:00
abstract::We show that a large class of finite factors has free entropy dimension less than or equal to one. This class includes all prime factors and many property T factors. ...
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.97.18.9881
更新日期:2000-08-29 00:00:00
abstract::A strain of Escherichia coli, selected on the basis of its resistance to colicin N, reveals distinct structural and functional alterations in unspecific OmpF porin. A single mutation [Gly-119-->Asp (G119D)] was identified in the internal loop L3 that contributes critically to the formation of the construction inside 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.91.22.10675
更新日期:1994-10-25 00:00:00
abstract::Glucagon-like peptide 1 (GLP-1) is a hormone derived from the preproglucagon molecule and is secreted by intestinal L cells. It is the most potent stimulator of glucose-induced insulin secretion and also suppresses in vivo acid secretion by gastric glands. A cDNA for the GLP-1 receptor was isolated by transient expres...
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.89.18.8641
更新日期:1992-09-15 00:00:00
abstract::Measurements of the water proton spinlattice relaxation (T(1)) in 106 human tumors confirms earlier results with animals [Damadian, R. (1971) Science 171, 1151-1153]. T(1) of all the tumors studied were significantly longer than T(1) of the corresponding normal tissues. Mean standard error and range were reported for ...
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.71.4.1471
更新日期:1974-04-01 00:00:00
abstract::Balanced genetic polymorphism has been proposed as a source from which to infer population history complementary to that of neutral genetic polymorphism, because genetic polymorphism maintained by balancing selection permits inferences about population size over much longer spans of time. However, empirical data for b...
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.96.1.168
更新日期:1999-01-05 00:00:00
abstract::Allergies are highly prevalent, and allergic responses can be triggered even in the absence of allergens due to Pavlovian conditioning to a specific cue. Here we show in humans suffering from allergic rhinitis that merely reencountering the environmental context in which an allergen was administered a week earlier is ...
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.1920564117
更新日期:2020-05-19 00:00:00
abstract::Network theory provides a powerful tool for the representation and analysis of complex systems of interacting agents. Here, we investigate the U.S. House of Representatives network of committees and subcommittees, with committees connected according to "interlocks," or common membership. Analysis of this network revea...
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.0500191102
更新日期:2005-05-17 00:00:00
abstract::RNA interfering is a eukaryote-specific gene silencing by 20∼23-nucleotide (nt) microRNAs and small interfering RNAs that recruit Argonaute proteins to complementary RNAs for degradation. In humans, Argonaute2 (AGO2) has been known as the only slicer while Argonaute3 (AGO3) barely cleaves RNAs. Therefore, the intrinsi...
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.2015026117
更新日期:2020-11-17 00:00:00
abstract::The nonclassical MHC class I-related (MHC-I) molecule HFE controls cellular iron homeostasis by a mechanism that has not been fully elucidated. We examined the regulation of HFE by K5, the E3 ubiquitin ligase encoded by Kaposi's sarcoma-associated herpesvirus (KSHV/HHV8), that is known to down-regulate classical MHC-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.1003421107
更新日期:2010-09-14 00:00:00
abstract::The testis-determining gene Sry is located on the short arm of the mouse Y chromosome in a region known to have undergone duplications and rearrangements in comparison with the equivalent portion of the human Y chromosome. Detailed analysis of the Sry genomic locus reveals a further difference in that the mouse Sry op...
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.89.17.7953
更新日期:1992-09-01 00:00:00
abstract::It has been shown that the pituitary contains a cytotropic factor (CTF) that stimulates the secretion of catecholamines by dopaminergic neurons of the hypothalamus. In the present study, CTF was purified from rat pituitaries and found by means of mass spectrometric analysis to be adenosine. This finding was corroborat...
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.92.12.5351
更新日期:1995-06-06 00:00:00
abstract::Time series data on arthropod populations are critical for understanding the magnitude, direction, and drivers of change. However, most arthropod monitoring programs are short-lived and restricted in taxonomic resolution. Monitoring data from the Arctic are especially underrepresented, yet critical to uncovering and u...
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.2002557117
更新日期:2021-01-12 00:00:00
abstract::Using the technique of DNA fingerprinting, we investigated the genetic structure within and among four wild-caught colonies (n = 50 individuals) of a eusocial mammal, the naked mole-rat (Heterocephalus glaber; Rodentia: Bathyergidae). We found that DNA fingerprints of colony-mates were strikingly similar and that betw...
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.87.7.2496
更新日期:1990-04-01 00:00:00
abstract::Brain function depends on adaptive self-organization of large-scale neural assemblies, but little is known about quantitative network parameters governing these processes in humans. Here, we describe the topology and synchronizability of frequency-specific brain functional networks using wavelet decomposition of magne...
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.0606005103
更新日期:2006-12-19 00:00:00
abstract::The bacterial superantigen staphylococcal enterotoxin A (SEA) is an extremely potent activator of T lymphocytes when presented on major histocompatibility complex (MHC) class II molecules. To develop a tumor-specific superantigen for cancer therapy, we have made a recombinant fusion protein of SEA and the Fab region 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.91.19.8945
更新日期:1994-09-13 00:00:00
abstract::Phosphorylation of purified microtubule-associated proteins (MAPs) inhibits the rate and extent of MAP-stimulated microtubule assembly. The extent of microtubule assembly is reduced as a result of a decrease in the fraction of tubulin polymerized, without a significant change in the critical protein concentration. The...
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.78.6.3413
更新日期:1981-06-01 00:00:00
abstract::Integrated hepadnaviral DNA in livers and tumors of chronic hepatitis B patients has been reported for many years. In this study, we investigated whether hepatitis B virus DNA integration occurs preferentially at sites of cell DNA damage. A single I-SceI homing endonuclease recognition site was introduced into the 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.0403925101
更新日期:2004-07-27 00:00:00
abstract::Targeted disruption of the pp60(src) (Src) gene has implicated this tyrosine kinase in osteoclast-mediated bone resorption and as a therapeutic target for the treatment of osteoporosis and other bone-related diseases. Herein we describe the discovery of a nonpeptide inhibitor (AP22408) of Src that demonstrates in vivo...
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.97.17.9373
更新日期:2000-08-15 00:00:00