Abstract:
:Incorporation experiments with labeled sirohydrochlorin and trimethylisobacteriochlorin demonstrate that ring contraction in vivo to the corrin macrocycle of vitamin B12 liberates acetic acid. The C-20 atom of the precursors becomes the acetate carboxyl carbon.
journal_name
Proc Natl Acad Sci U S Aauthors
Battersby AR,Bushell MJ,Jones C,Lewis NG,Pfenninger Adoi
10.1073/pnas.78.1.13subject
Has Abstractpub_date
1981-01-01 00:00:00pages
13-5issue
1eissn
0027-8424issn
1091-6490journal_volume
78pub_type
杂志文章abstract::The rise of inorganic-biological hybrid organisms for solar-to-chemical production has spurred mechanistic investigations into the dynamics of the biotic-abiotic interface to drive the development of next-generation systems. The model system, Moorella thermoacetica-cadmium sulfide (CdS), combines an inorganic semicond...
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.1610554113
更新日期:2016-10-18 00:00:00
abstract::We have previously shown that in neutrophils deprived of granulocyte colony-stimulating factor, apoptosis is preceded by acidification and that the protection against apoptosis conferred on neutrophils by granulocyte colony-stimulating factor is dependent upon delay of this acidification. To test the hypothesis that 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.93.2.654
更新日期:1996-01-23 00:00:00
abstract::The topology of the tight junction is probed by introducing dipicrylamine (dpa-), a lipid-soluble anion, into the membranes of hepatocyte pairs in culture. Once partitioned into the membrane, dpa- ions are free to move in the hydrophobic core of the membrane, where their mobile charges greatly increase membrane capaci...
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.88.20.9365
更新日期:1991-10-15 00:00:00
abstract::The structures of human platelet alpha 2-adrenergic receptors and rat liver alpha 1-adrenergic receptors were compared by utilizing isoelectric focusing, NaDodSO4/PAGE, and monoclonal antibody crossreactivity. Digitonin-solubilized alpha 1- and alpha 2-adrenergic receptors have an identical isoelectric point of 4.6. 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.82.14.4842
更新日期:1985-07-01 00:00:00
abstract::Prions are composed solely of an alternatively folded isoform of the prion protein (PrP), designated PrP(Sc). N-terminally truncated PrP(Sc), denoted PrP 27-30, retains infectivity and polymerizes into rods with the ultrastructural and tinctorial properties of amyloid. We report here that some polyoxometalates (POMs) ...
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.0812770106
更新日期:2009-03-10 00:00:00
abstract::Calcium, a universal second messenger, regulates diverse cellular processes in eukaryotes. Ca2+ and Ca2+/calmodulin-regulated protein phosphorylation play a pivotal role in amplifying and diversifying the action of Ca(2+)-binding domain was cloned and characterized from lily. The cDNA clone contains an open reading 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.92.11.4897
更新日期:1995-05-23 00:00:00
abstract::The electron tunnelling distance between redox enzymes is estimated. The energy transfer mechanism between a pair of charges is described. The dielectric degrees of freedom are incorporated into the electron transfer rate formula. ...
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.73.8.2770
更新日期:1976-08-01 00:00:00
abstract::Polyploidy, which results from whole genome duplication (WGD), has shaped the long-term evolution of eukaryotic genomes in all kingdoms. Polyploidy is also implicated in adaptation, domestication, and speciation. Yet when WGD newly occurs, the resulting neopolyploids face numerous challenges. A particularly pernicious...
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.1919459117
更新日期:2020-04-21 00:00:00
abstract::The DNA-binding protein CCCTC-binding factor (CTCF) and the cohesin complex function together to shape chromatin architecture in mammalian cells, but the molecular details of this process remain unclear. Here, we demonstrate that a 79-aa region within the CTCF N terminus is essential for cohesin positioning at CTCF bi...
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.1911708117
更新日期:2020-01-28 00:00:00
abstract::Mutant I1A cells, lacking IL-1 receptor-associated kinase (IRAK) mRNA and protein, have been used to study the involvement of IRAK in NFkappaB and c-Jun N-terminal kinase (JNK) activation. A series of IRAK deletion constructs were expressed in I1A cells, which were then tested for their ability to respond to IL-1. Bot...
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.071054198
更新日期:2001-04-10 00:00:00
abstract::Somatostatin (somatotropin release-inhibiting factor; SRIF) is a tetradecapeptide present in brain, pancreas, gastrointestinal tract, and thyroid that inhibits the secretion or action of several hormones in these tissues. We observed that the toad urinary bladder contains concentrations of endogenous somatostatin (8.0...
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.77.8.4984
更新日期:1980-08-01 00:00:00
abstract::The 1H NMR signal from oxymyoglobin, a low-concentration diamagnetic protein, is visible in myocardial tissue. The methyl group of the Val-E11 resonates in a clear spectral region at -2.76 ppm and responds to dynamic changes in cellular oxygenation. With CO, the signal shifts to -2.4 ppm. The Val-E11 peak assignment 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.89.10.4731
更新日期:1992-05-15 00:00:00
abstract::A vestigial, nonphotosynthetic plastid has been identified recently in protozoan parasites of the phylum Apicomplexa. The apicomplexan plastid, or "apicoplast," is indispensable, but the complete sequence of both the Plasmodium falciparum and Toxoplasma gondii apicoplast genomes has offered no clue as to what essentia...
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.95.21.12352
更新日期:1998-10-13 00:00:00
abstract::The role of missense changes in BRCA1 in breast cancer susceptibility has been difficult to establish. We used comparative evolutionary methods to identify potential functionally important amino acid sites in exon 11 and missense changes likely to disrupt gene function, aligning sequences from 57 eutherian mammals and...
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.0237285100
更新日期:2003-02-04 00:00:00
abstract::Circular RNA replicons have been reported in plants and, in one case, in animal cells. We describe such an element in yeast. In certain yeast strains, a 20S RNA species appears on transfer of cells to acetate medium. This phenotype shows cytoplasmic (non-Mendelian) inheritance and the 20S RNA is associated with 23-kDa...
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.87.19.7628
更新日期:1990-10-01 00:00:00
abstract::Direct structural insights on the fundamental mechanisms of permeation, selectivity, and gating remain unavailable for the Na(+) and Ca(2+) channel families. Here, we report the spectroscopic structural characterization of the isolated Voltage-Sensor Domain (VSD) of the prokaryotic Na(+) channel NaChBac in a lipid bil...
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.0914109107
更新日期:2010-03-23 00:00:00
abstract::Von Willebrand factor (vWF) was purified from the plasma of a patient with type IIB von Willebrand disease (vWF from such a patient, IIB vWF) who had a normal platelet count and showed no evidence of spontaneous platelet aggregation. Large multimers of IIB vWF were absent from purified preparations and from plasma. Ri...
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.82.21.7424
更新日期:1985-11-01 00:00:00
abstract::Ubiquitin is a highly conserved protein that is encoded by a multigene family. It is generally believed that this gene family is subject to concerted evolution, which homogenizes the member genes of the family. However, protein homogeneity can be attained also by strong purifying selection. We therefore studied the 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.97.20.10866
更新日期:2000-09-26 00:00:00
abstract::Kinetics of growth and decay of triplet states of molecules at known orientation in a magnetic field have been measured. Amplitudes of the zero field eigenstates in each of the eigenstates at finite field were varied by choice of orientation. No interference between the amplitudes of the zero field states was found in...
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.72.11.4203
更新日期:1975-11-01 00:00:00
abstract::The failure to induce self-tolerance of simian virus 40 large tumor antigen (T antigen) expressed in the pancreatic beta cells of transgenic mice results in an autoimmune response against this protein and the cells that synthesize it. In every transgenic mouse with delayed onset of T-antigen expression and consequent ...
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.87.19.7487
更新日期:1990-10-01 00:00:00
abstract::Homozygous uniparental mouse embryos, produced by microsurgical removal of the male pronucleus from fertilized eggs and diploidization of the female pronucleus with cytochalasin, were surrounded with blastomeres from normal embryos to produce chimeric embryos. A few of these chimeras developed into viable adults, and ...
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.83.17.6509
更新日期:1986-09-01 00:00:00
abstract::Pressures of 200-1000 atmospheres (20-100 MPa) are found to decrease significantly the amount of phosphate (H32PO4-2)transported into the rabbit erythrocyte under otherwise physiological conditions. Such compression does not cause irreversible morphological changes or result in membrane disruption. The findings are in...
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.73.8.2767
更新日期:1976-08-01 00:00:00
abstract::Autocatalytic activation of an initiator caspase triggers the onset of apoptosis. In dying cells, caspase-9 activation is mediated by a multimeric adaptor complex known as the Apaf-1 apoptosome. The molecular mechanism by which caspase-9 is activated by the Apaf-1 apoptosome remains largely unknown. Here we demonstrat...
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.1418000111
更新日期:2014-11-18 00:00:00
abstract::Independent transgene insertions differ in expression based on their location in the genome; these position effects are of interest because they reflect the influence of genome organization on gene regulation. Position effects also represent potentially insurmountable obstacles to the rigorous functional comparison 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.95.26.15513
更新日期:1998-12-22 00:00:00
abstract::The frequency of recombination between the G gamma-globin (HBG2) and parathyroid hormone (PTH) loci on the short arm of human chromosome 11 was estimated by typing greater than 700 single-sperm samples from two males. The sperm-typing technique employed involves the polymerase chain reaction and allele-specific oligon...
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.86.23.9389
更新日期:1989-12-01 00:00:00
abstract::Based on the cell surface expression of CD4 and CD8 molecules, murine thymocytes can be divided into four populations: these include CD4-, CD8- double-negative and CD4+, CD8+ double-positive subpopulations, both of which consist largely of immature cells, and the single positive, CD4+ or CD8+, subsets that contain fun...
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.85.22.8633
更新日期:1988-11-01 00:00:00
abstract::[3H]Thymidine-labeled progeny DNA was isolated after infection of Escherichia coli with two different bacteriophage T4 mutants. These strands were isolated shortly after the initiation of DNA replication and hybridized to 15 different (EcoRI) T4 restriction fragments cloned in plasmid vectors. Uniformly labeled T4 [32...
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.76.12.6137
更新日期:1979-12-01 00:00:00
abstract::Mutations in sequences at the C terminus of the capsid precursor protein of human immunodeficiency virus type 1 that affect the viral p6 protein prevent release of budded virus particles from the cell surface. The experiments reported here define an important step in the life cycle of the virus, the release of the bud...
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.88.8.3195
更新日期:1991-04-15 00:00:00
abstract::Although(,) vascular remodeling is a hallmark of many chronic inflammatory disorders such as rheumatoid arthritis, inflammatory bowel disease, and psoriasis, anti-vascular strategies to treat these conditions have received little attention to date. We investigated the anti-inflammatory activity of systemic blockade 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.0907550106
更新日期:2009-12-15 00:00:00
abstract::Host-defense cationic antimicrobial peptides ( approximately 12-50 aa long) play an essential protective role in the innate immune system of all organisms. Lipopeptides, however, are produced only in bacteria and fungi during cultivation, and they are composed of specific lipophilic moieties attached to anionic peptid...
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.0606129103
更新日期:2006-10-24 00:00:00