Abstract:
:Lipid interactions with the integral membrane protein Na,K-ATPase (ATP phosphohydrolase, EC 3.6.1.3) purified from the electric organ of Electrophorus electricus were studied by spin labeling. A protein-associated component (boundary layer) in equilibrium with the fluid bilayer is clearly evident in the electron spin resonance spectra. The influence of charge on this equilibrium was determined by varying the head group of the lipid while maintaining the chain length and the position of the label constant. The lipid spin labels were 14-proxylstearylmethyl phosphate and the corresponding dimethylphosphate, alcohol, and quaternary amine. By using a pairwise spectral analysis, as well as a conventional spectral analysis, the binding affinity was found to decrease in the order of negative greater than neutral greater than positive charges. The fraction bound decreased from about 0.57 for the negatively charged phosphate to 0.25 for the positively charged quaternary amine. The amount of each bound lipid was nearly constant over the temperature range investigated (5-35 degrees C). High salt concentrations reversibly abolished the selectivity between the labels, confirming the role of charge in the binding equilibria.
journal_name
Proc Natl Acad Sci U S Aauthors
Brotherus JR,Jost PC,Griffith OH,Keana JF,Hokin LEdoi
10.1073/pnas.77.1.272subject
Has Abstractpub_date
1980-01-01 00:00:00pages
272-6issue
1eissn
0027-8424issn
1091-6490journal_volume
77pub_type
杂志文章abstract::Activator protein-1 (AP-1) is a crucial transcription factor implicated in numerous cancers. For this reason, nine homologues of the AP-1 leucine zipper region have been characterized: Fos (c-Fos, FosB, Fra1, and Fra2), Jun (c-Jun, JunB, and JunD), and semirational library-designed winning peptides FosW and JunW. 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.0509880103
更新日期:2006-06-13 00:00:00
abstract::Cytochrome c maturation in Escherichia coli requires the ccm operon, which encodes eight membrane proteins (CcmABCDEFGH). CcmE is a periplasmic heme chaperone that binds heme covalently and transfers it onto apocytochrome c in the presence of CcmF, CcmG, and CcmH. In this work we addressed the functions of the ccmABCD...
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.96.11.6462
更新日期:1999-05-25 00:00:00
abstract::Cyanobacteria, blue-green algae, are the most abundant autotrophs in aquatic environments and form the base of all aquatic food chains by fixing carbon and nitrogen into cellular biomass. The single most important nutrient for photosynthesis and growth is nitrate, which is severely limiting in many aquatic environment...
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.0602517103
更新日期:2006-06-27 00:00:00
abstract::Homopyrimidine oligonucleotides bind to the major groove of a complementary homopyrimidine.homopurine stretch by triple helix formation. The bla gene from transposon Tn3 contains a homopyrimidine.homopurine sequence of 13 base pairs located just downstream of the RNA polymerase binding site. A 13-mer homopyrimidine ol...
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.89.2.504
更新日期:1992-01-15 00:00:00
abstract::Proteolytic removal of the pre-segment from growing nascent chains of pre-human placental lactogen (hPL) occurred during in vitro translation of placental mRNA if crude membranes derived from ascites lysates, dog pancreas, or rat liver rough endoplasmic reticulum were added to the translation mixtures. The cotranslati...
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.76.9.4225
更新日期:1979-09-01 00:00:00
abstract::Improving global yields of important agricultural crops is a complex challenge. Enhancing yield and resource use by engineering improvements to photosynthetic carbon assimilation is one potential solution. During the last 40 million years C(4) photosynthesis has evolved multiple times, enabling plants to evade the cat...
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.1109503108
更新日期:2011-08-30 00:00:00
abstract::Proteins fold through a variety of mechanisms. For a given protein, folding routes largely depend on the protein's stability and its native-state geometry, because the landscape is funneled. These ideas are corroborated for cytochrome c by using a coarse-grained topology-based model with a perfect funnel landscape tha...
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.0505274102
更新日期:2005-08-30 00:00:00
abstract::The suprachiasmatic nucleus (SCN) is the principal circadian pacemaker of mammals, coordinating daily rhythms of behavior and metabolism. Circadian timekeeping in SCN neurons revolves around transcriptional/posttranslational feedback loops, in which Period (Per) and Cryptochrome (Cry) genes are negatively regulated by...
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.1101767108
更新日期:2011-08-23 00:00:00
abstract::Cortical networks that have been found to operate close to a critical point exhibit joint activations of large numbers of neurons. However, in motor cortex of the awake macaque monkey, we observe very different dynamics: massively parallel recordings of 155 single-neuron spiking activities show weak fluctuations on th...
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.1818972116
更新日期:2019-06-25 00:00:00
abstract::T cells transferred into severe lymphopenic hosts undergo rapid proliferation known as "endogenous proliferation" that are distinct from conventional homeostatic proliferation. Unlike homeostatic proliferation, cytokines, such as IL-7 are dispensable, yet TCR:MHC interaction is essential for this process to occur. How...
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.0909954106
更新日期:2009-12-01 00:00:00
abstract::Chemical labeling of proteins inside of living cells can enable studies of the location, movement, and function of proteins in vivo. Here we demonstrate an approach for chemical labeling of proteins that uses the high-affinity interaction between an FKBP12 mutant (F36V) and a synthetic, engineered ligand (SLF'). A flu...
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.0401609101
更新日期:2004-07-06 00:00:00
abstract::Protein kinase P (PK-P) activated by histones or certain other basic compounds has been purified previously from yeast [Yanagita, Y., Abdel-Ghany, M., Raden, D., Nelson, N. & Racker, E. (1987) Proc. Natl. Acad. Sci. USA 84, 925-929]. It is shown here that PK-P is present in solubilized membranes of A-431 carcinoma cel...
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.84.24.8888
更新日期:1987-12-01 00:00:00
abstract::By using a structure-based computer-assisted search, we have found a butyrophenone derivative that is a selective inhibitor of the human immunodeficiency virus 1 (HIV-1) protease. The computer program creates a negative image of the active site cavity using the crystal structure of the HIV-1 protease. This image was c...
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.87.17.6644
更新日期:1990-09-01 00:00:00
abstract::Oxidation of molecular hydrogen catalyzed by [NiFe] hydrogenases is a widespread mechanism of energy generation among prokaryotes. Biosynthesis of the H2-oxidizing enzymes is a complex process subject to positive control by H2 and negative control by organic energy sources. In this report we describe a novel signal tr...
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.95.21.12474
更新日期:1998-10-13 00:00:00
abstract::Platelets are best known for their vasoprotective responses to injury and inflammation. Here, we have asked whether they also support vascular integrity when neither injury nor inflammation is present. Changes in vascular barrier function in dermal and meningeal vessels were measured in real time in mouse models using...
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.2007642117
更新日期:2020-09-29 00:00:00
abstract::[Ala3-15N][Val1]Gramicidin A has been prepared by solid-phase peptide synthesis and studied by solid-state 15N nuclear magnetic resonance spectroscopy. The synthesis of desformyl[Ala3-15N][Val1]gramicidin A employed N-hydroxysuccinimide esters of 9-fluorenylmethoxycarbonyl-N alpha-amino acids and completely avoided th...
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.85.5.1384
更新日期:1988-03-01 00:00:00
abstract::A murine monoclonal antibody (OKT9) raised against human leukemic cells binds to a wide variety of leukemia and tumor cell lines and to a minority of leukemia cells taken directly from patients. Fetal thymus and liver are strongly reactive as are some normal, immature hemopoietic cells and activated lymphocytes. React...
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.78.7.4515
更新日期:1981-07-01 00:00:00
abstract::Kdo (3-deoxy-d-manno-oct-2-ulosonic acid) is an eight-carbon sugar mostly confined to Gram-negative bacteria. It is often involved in attaching surface polysaccharides to their lipid anchors. α-Kdo provides a bridge between lipid A and the core oligosaccharide in all bacterial LPSs, whereas an oligosaccharide of β-Kdo...
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.1603146113
更新日期:2016-05-31 00:00:00
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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.78.4.2559
更新日期:1981-04-01 00:00:00
abstract::The phosphatase and tensin homolog (PTEN) is a tumor suppressor that is inactivated in many human cancers. PTEN loss has been associated with resistance to inhibitors of the epidermal growth factor receptor (EGFR), but the molecular basis of this resistance is unclear. It is believed that unopposed phosphatidylinosito...
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.0911188107
更新日期:2010-04-06 00:00:00
abstract::Different splice variants of the proinflammatory cytokine IL-32 are found in various tissues; their putative differences in biological function remain unknown. In the present study, we report that IL-32γ is the most active isoform of the cytokine. Splicing to one less active IL-32β appears to be a salvage mechanism to...
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.1016005108
更新日期:2011-03-22 00:00:00
abstract::Cereal agriculture originated with the domestication of barley and early forms of wheat in the Fertile Crescent. There has long been speculation that barley was domesticated more than once. We use differences in haplotype frequency among geographic regions at multiple loci to infer at least two domestications of barle...
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.0611377104
更新日期:2007-02-27 00:00:00
abstract::Through a process called "bioturbation," burrowing macrofauna have altered the seafloor habitat and modified global carbon cycling since the Cambrian. However, the impact of macrofauna on the community structure of microorganisms is poorly understood. Here, we show that microbial communities across bioturbated, but ge...
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.1917494117
更新日期:2020-07-07 00:00:00
abstract::Chlorpromazine (3 x 10(-4)M) prevents the stimulation of adenyl cyclase activity in thyroid membranes produced by thyrotropin and prostaglandin, ACTH stimulation of adenyl cyclase in adrenal tissue, and glucagon- and epinephrine-stimulation of adenyl cyclase activity in liver. Baseline activity is unaffected. Parathyr...
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.65.2.454
更新日期:1970-02-01 00:00:00
abstract::Rhythmic, spontaneously pulsating cardiac cells cultured from newborn rats are immediately stimulated to beat faster by addition of a number of tubulin-binding agents but not by their non-tubulin-binding analogues. The tubulin-binding agents tested include vinblastine, vincristine, navelbine, two analogs of vinblastin...
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.89.4.1256
更新日期:1992-02-15 00:00:00
abstract::A cloned complementary DNA sequence has been isolated from a human placental cDNA library in the bacteriophage expression vector lambda gt11 after screening with polyclonal antibodies against human placental aromatase-system cytochrome P-450 (P-450Arom). A single recombinant clone, lambda hAROM1, was characterized by ...
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.83.17.6387
更新日期:1986-09-01 00:00:00
abstract::Two-dimensional Raman-terahertz (THz) spectroscopy is presented as a multidimensional spectroscopy directly in the far-IR regime. The method is used to explore the dynamics of the collective intermolecular modes of liquid water at ambient temperatures that emerge from the hydrogen-bond networks water forming. Two-dime...
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.1317459110
更新日期:2013-12-17 00:00:00
abstract::Understanding the detailed mechanism of the activation of voltage-gated ion channels has been a problem of great current interest. Reliable molecular simulations of voltage effects present a major challenge because meaningful converging microscopic simulations are not yet available and macroscopic treatments involve m...
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.1121094109
更新日期:2012-02-28 00:00:00
abstract::Harvey and Kirsten murine sarcoma viruses each encode a structurally and functionally related 21-kilodalton protein (p21), which is the transforming protein of each virus. Using probes from the 0.9-kilobase (kb) p21-coding region of each virus (called v-Ha-ras and v-Ki-ras, respectively), we have molecularly cloned fr...
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.79.16.4848
更新日期:1982-08-01 00:00:00
abstract::DNA photolyase is a pyrimidine-dimer repair enzyme that uses visible light. Photolyase generally contains two chromophore cofactors. One is a catalytic cofactor directly contributing to the repair of a pyrimidine-dimer. The other is a light-harvesting cofactor, which absorbs visible light and transfers energy to the c...
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.241371398
更新日期:2001-11-20 00:00:00