Abstract:
:The results of electron-nuclear double resonance and electron paramagnetic resonance (EPR) studies on the hydrogen peroxide compound of yeast cytochrome c peroxidase are inconsistent with previous proposals for the source of the EPR signal in this compound, in particular with its identification with an aromatic amino acid radical such as would arise by oxidation of a tryptophanyl side chain. The present observations lead us to propose that the EPR signal is associated with a cluster containing at least one methionine and in which proximate side chains share the charge created by loss of one electron.
journal_name
Proc Natl Acad Sci U S Aauthors
Hoffman BM,Roberts JE,Brown TG,Kang CH,Margoliash Edoi
10.1073/pnas.76.12.6132subject
Has Abstractpub_date
1979-12-01 00:00:00pages
6132-6issue
12eissn
0027-8424issn
1091-6490journal_volume
76pub_type
杂志文章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::K+ channels, which have been linked to regulation of electrogenic solute transport as well as Ca2+ influx, represent a locus in hepatocytes for the concerted actions of hormones that employ Ca2+ and cAMP as intracellular messengers. Despite considerable study, the single-channel basis for synergistic effects of Ca2+ 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.92.15.7115
更新日期:1995-07-18 00:00:00
abstract::Erythropoietin (Epo) is a glycoprotein factor that specifically regulates the proliferation and differentiation of erythroid progenitor cells. Here we describe the isolation of Epo-responsive mouse erythroleukemia cell line SKT6, the characterization of the specific binding of biologically active 125I-labeled human Ep...
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.84.12.4126
更新日期:1987-06-01 00:00:00
abstract::A closed duplex DNA molecule relaxed and containing nucleosomes has a different linking number from the same molecule relaxed and without nucleosomes. What does this say about the structure of the nucleosome? A mathematical study of this question is made, representing the DNA molecule by a ribbon. It is shown that 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.75.8.3557
更新日期:1978-08-01 00:00:00
abstract::Rotifers of the asexual class Bdelloidea are unusual in possessing two or more divergent copies of every gene that has been examined. Phylogenetic analysis of the heat-shock gene hsp82 and the TATA-box-binding protein gene tbp in multiple bdelloid species suggested that for each gene, each copy belonged to one of two ...
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.2136686100
更新日期:2004-02-10 00:00:00
abstract::Phylogenetic comparison of rRNA sequences has suggested that a pseudoknot structure exists in the central domain of small-subunit rRNA. In Escherichia coli 16S rRNA, this pseudoknot would form when positions 570 and 571 pair with positions 865 and 866. Mutations were introduced into this pseudoknot at the phylogenetic...
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.91.23.11148
更新日期:1994-11-08 00:00:00
abstract::The ability to predictably control the coassembly of multiple nanoscale building blocks, especially those with disparate chemical and physical properties such as biomolecules and inorganic nanoparticles, has far-reaching implications in catalysis, sensing, and photonics, but a generalizable strategy for engineering sp...
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.1503533112
更新日期:2015-04-14 00:00:00
abstract::Explaining the variation between human languages and the constraints on that variation is a core goal of linguistics. In the last 20 y, it has been claimed that many striking universals of cross-linguistic variation follow from a hypothetical principle that dependency length--the distance between syntactically related...
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.1502134112
更新日期:2015-08-18 00:00:00
abstract::The role of endocytosis in the control of EGF receptor (EGFR) activation and cell signaling was explored by using mouse fibroblasts in which dynamin was conditionally depleted. Dynamin is a GTPase shown to play an important role in the control clathrin mediated endocytosis of EGFR and other cell surface receptors. 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.1200164109
更新日期:2012-03-20 00:00:00
abstract::A central unresolved issue in evolutionary biology is how metabolic innovations emerge. Low-level enzymatic side activities are frequent and can potentially be recruited for new biochemical functions. However, the role of such underground reactions in adaptation toward novel environments has remained largely unknown 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.1406102111
更新日期:2014-08-12 00:00:00
abstract::It is well established that pregnancy early in life reduces the risk of breast cancer in women and that this effect is universal. This phenomenon of parity protection against mammary cancer is also observed in rodents. Earlier studies have demonstrated that short-term administration of estradiol (E) in combination wit...
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.201393798
更新日期:2001-09-25 00:00:00
abstract::The specificity with which the genetic code is read in protein synthesis, and with which other highly specific biosynthetic reactions take place, can be increased above the level available from free energy differences in intermediates or kinetic barriers by a process defined here as kinetic proofreading. A simple kine...
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.71.10.4135
更新日期:1974-10-01 00:00:00
abstract::Optimal flowering time is critical to the success of modern agriculture. Sorghum is a short-day tropical species that exhibits substantial photoperiod sensitivity and delayed flowering in long days. Genotypes with reduced photoperiod sensitivity enabled sorghum's utilization as a grain crop in temperate zones worldwid...
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.1106212108
更新日期:2011-09-27 00:00:00
abstract::Bacterial transpeptidase and transglycosylase on the surface are essential for cell wall synthesis, and many antibiotics have been developed to target the transpeptidase; however, the problem of antibiotic resistance has arisen and caused a major threat in bacterial infection. The transglycosylase has been considered ...
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.1203900109
更新日期:2012-04-24 00:00:00
abstract::Immune responses to several soluble antigens were compared between B6.C-H-2bm12 mutant and wild-type B6 mice by using a lymph node T-cell proliferation assay. B6.C-H-2bm12 mice failed to respond to beef insulin whereas other IA gene-controlled responses, such as response to poly(L-Tyr, L-Glu)--poly(DL-Ala, L-Lys) 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.78.10.6406
更新日期:1981-10-01 00:00:00
abstract::Activating mutations in BRAF are found in 50% of melanomas and although treatment with BRAF inhibitors (BRAFi) is effective, resistance often develops. We now show that recently discovered NRAS isoform 2 is up-regulated in the setting of BRAF inhibitor resistance in melanoma, in both cell lines and patient tumor tissu...
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.1704371114
更新日期:2017-09-05 00:00:00
abstract::Chromosome region 11p15.5 harbors unidentified genes involved in neoplasms and in the genetic disease Beckwith-Wiedemann syndrome. The genetic analysis of a 170-kb region at 11p15.5 between loci D11S601 and D11S679 resulted in the identification of six transcriptional units. Three genes, hNAP2, CDKN1C, and KVLQT1, are...
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.95.7.3873
更新日期:1998-03-31 00:00:00
abstract::The prefrontal cortex plays a fundamental role in the working memory functions of the cerebral cortex and is also the site of dysfunction in several neurological and psychiatric disorders, including schizophrenia. Prefrontal neurons are distinguished by their capacity for sustained activity during the time a stimulus ...
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.011524298
更新日期:2001-01-02 00:00:00
abstract::Bub1 is a kinase believed to function primarily in the mitotic spindle checkpoint. Mutation or aberrant Bub1 expression is associated with chromosomal instability, aneuploidy, and human cancer. We now find that targeting Bub1 by RNAi or simian virus 40 (SV40) large T antigen in normal human diploid fibroblasts results...
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.0703164104
更新日期:2007-05-15 00:00:00
abstract::Apoptosis has been shown to be a significant form of cell loss in many diseases. Detachment of photoreceptors from the retinal pigment epithelium, as seen in various retinal disorders, causes photoreceptor loss and subsequent vision decline. Although caspase-dependent apoptotic pathways are activated after retinal det...
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.1009179107
更新日期:2010-12-14 00:00:00
abstract::Migration of the cells in osteoblastic lineage, including preosteoblasts and osteoblasts, has been postulated to influence bone formation. However, the molecular bases that link preosteoblastic/osteoblastic cell migration and bone formation are incompletely understood. Nck (noncatalytic region of tyrosine kinase; coll...
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.1518253112
更新日期:2015-12-15 00:00:00
abstract::Mammalian cells typically contain thousands of copies of mitochondrial DNA assembled into hundreds of nucleoids. Here we analyzed the dynamic features of nucleoids in terms of mitochondrial membrane dynamics involving balanced fusion and fission. In mitochondrial fission GTPase dynamin-related protein (Drp1)-deficient...
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.1301951110
更新日期:2013-07-16 00:00:00
abstract::Zeolite and zeolite-like molecular sieves are being used in a large number of applications such as adsorption and catalysis. Achievement of the long-standing goal of creating a chiral, polycrystalline molecular sieve with bulk enantioenrichment would enable these materials to perform enantioselective functions. Here, ...
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.1704638114
更新日期:2017-05-16 00:00:00
abstract::We previously reconstituted Z rings in tubular multilamellar liposomes with FtsZ-YFP-mts, where mts is a membrane-targeting amphiphilic helix. These reconstituted Z rings generated a constriction force but did not divide the thick-walled liposomes. Here we developed a unique system to observe Z rings in unilamellar li...
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.1222254110
更新日期:2013-07-02 00:00:00
abstract::A major part of the present understanding of the molecular basis of signal transduction has been gained from in vitro studies using classical biochemical methods. In this study, we used 31P NMR spectroscopy to investigate the response of live M2R mouse melanoma cells to stimulation by melanocyte-stimulating hormone (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.88.4.1506
更新日期:1991-02-15 00:00:00
abstract::Spatial organization of the binding sites for the priming substrate, the template DNA, and the transcription inhibitor rifampicin (Rif) in Escherichia coli RNA polymerase (EC 2.7.7.6) was probed with chimeric compounds in which Rif is covalently attached to a ribonucleotide. The compounds bind to RNA polymerase in bif...
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.91.25.12036
更新日期:1994-12-06 00:00:00
abstract::Previous work showed that cultured human pancreatic cancer cells overexpress the epidermal growth factor (EGF) receptor. In the present study, we sought to determine whether some of these cell lines produce transforming growth factor alpha (TGF-alpha). Utilizing a radiolabeled TGF-alpha cDNA in hybridization experimen...
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.84.21.7567
更新日期:1987-11-01 00:00:00
abstract::The emergence of multidrug-resistant (MDR) tuberculosis (TB) highlights the urgent need to understand the mechanisms of resistance to the drugs used to treat this disease. The aminoglycosides kanamycin and amikacin are important bactericidal drugs used to treat MDR TB, and resistance to one or both of these drugs is 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.0907925106
更新日期:2009-11-24 00:00:00
abstract::Evolutionary innovations often arise from complex genetic and ecological interactions, which can make it challenging to understand retrospectively how a novel trait arose. In a long-term experiment, Escherichia coli gained the ability to use abundant citrate (Cit(+)) in the growth medium after ∼31,500 generations of e...
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.1314561111
更新日期:2014-02-11 00:00:00
abstract::Scientific cinematography using ultrafast optical imaging is a common tool to study motion. In opaque organisms or structures, X-ray radiography captures sequences of 2D projections to visualize morphological dynamics, but for many applications full four-dimensional (4D) spatiotemporal information is highly desirable....
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.1308650111
更新日期:2014-03-18 00:00:00