Abstract:
:After prolonged exposure to ascorbate, collagen synthesis in cultured human skin fibroblasts increased approximately 8-fold with no significant change in synthesis of noncollagen protein. This effect of ascorbate appears to be unrelated to its cofactor function in collagen hydroxylation. The collagenous protein secreted in the absence of added ascorbate was normal in hydroxylysine but was mildly deficient in hydroxyproline. In parallel experiments, lysine hydroxylase (peptidyllysine, 2-oxoglutarate:oxygen 5-oxidoreductase, EC 1.14.11.4) activity increased 3-fold in response to ascorbate administration whereas proline hydroxylase (prolyl-glycyl-peptide, 2-oxoglutarate:oxygen oxidoreductase, EC 1.14.11.2) activity decreased considerably. These results suggest that collage polypeptide synthesis, posttranslational hydroxylations, and activities of the two hydroxylases are independently regulated by ascorbate.
journal_name
Proc Natl Acad Sci U S Aauthors
Murad S,Grove D,Lindberg KA,Reynolds G,Sivarajah A,Pinnell SRdoi
10.1073/pnas.78.5.2879subject
Has Abstractpub_date
1981-05-01 00:00:00pages
2879-82issue
5eissn
0027-8424issn
1091-6490journal_volume
78pub_type
杂志文章abstract::We have shown recently that the temporal order of antioxidant consumption in human blood plasma exposed to a constant flux of aqueous peroxyl radicals is ascorbate = protein thiols greater than bilirubin greater than urate greater than alpha-tocopherol and that detectable lipid peroxidation starts only after ascorbate...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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abstract::Historical collapse of ancient states or civilizations has raised new awareness about its possible relevance to current issues of sustainability, in the context of global change. This Special Feature examines 12 case studies of societies under stress, of which seven suffered severe transformation. Outcomes were comple...
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2005-07-19 00:00:00
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更新日期:2003-12-23 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1988-10-01 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
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更新日期:2007-01-02 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2001-12-04 00:00:00
abstract::A typical homing endonuclease initiates mobility of its group I intron by recognizing DNA both upstream and downstream of the intron insertion site of intronless alleles, preventing the endonuclease from binding and cleaving its own intron-containing allele. Here, we describe a GIY-YIG family homing endonuclease, I-Bm...
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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abstract::Pro-Leu-Gly-NH2 (MIF) and several structural analogues, all injected in 50-microgram doses daily in mice receiving morphine chronically, were found to prevent development of physical dependence as measured by changes in body temperature associated with naloxone-induced withdrawal. Dose-response studies, using again a ...
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更新日期:1979-01-01 00:00:00
abstract::This work argues that, in a polarized environment, scientists can minimize the likelihood that the audience's biased processing will lead to rejection of their message if they not only eschew advocacy but also, convey that they are sharers of knowledge faithful to science's way of knowing and respectful of the audienc...
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abstract::Helicobacter pylori VacA, a pore-forming toxin secreted by an autotransporter pathway, causes multiple alterations in human cells, contributes to the pathogenesis of peptic ulcer disease and gastric cancer, and is a candidate antigen for inclusion in an H. pylori vaccine. Here, we present a 2.4-A crystal structure of ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2011-03-15 00:00:00
abstract::Design and synthesis of 3D metallic carbon that is stable under ambient conditions has been a long-standing dream. We predict the existence of such phases, T6- and T14-carbon, consisting of interlocking hexagons. Their dynamic, mechanical, and thermal stabilities are confirmed by carrying out a variety of state-of-the...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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abstract::T-box riboswitches control transcription of downstream genes through the tRNA-binding formation of terminator or antiterminator structures. Previously reported T-boxes were described as single-specificity riboswitches that can bind specific tRNA anticodons through codon-anticodon interactions with the nucleotide tripl...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2013-07-30 00:00:00