Abstract:
:We have identified two chromosomal genes of Escherichia coli K12 that are required for the expression of conjugative plasmid functions in the presence of normal plasmid DNA. Hfr cells with mutations in both of these genes are resistant to donor-specific bacteriophage and defective as conjugal donors. These characteristics can be attributed to the inability of mutant Hfr cells to elaborate F-pili, surface organelles required both for conjugal donor ability and for sensitivity to donor-specific bacteriophages. Mutant cells are also defective in surface exclusion, the property of donor cells to act as poor conjugal recipients. This defect can be attributed in part to a reduction in the amount of the F-plasmid traT gene product in the outer membrane of mutant cells; this protein is one of two plasmid gene products required for the full expression of surface exclusion. We have designated the chromosomal genes identified by these mutations as cpxA and cpxB; the mnemonic cpx signifying conjugative plasmid expression.
journal_name
Proc Natl Acad Sci U S Aauthors
McEwen J,Silverman Pdoi
10.1073/pnas.77.1.513subject
Has Abstractpub_date
1980-01-01 00:00:00pages
513-7issue
1eissn
0027-8424issn
1091-6490journal_volume
77pub_type
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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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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
pub_type: 杂志文章,随机对照试验
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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abstract::Mutations in copper/zinc superoxide dismutase (SOD1) are causative for dominantly inherited amyotrophic lateral sclerosis (ALS). Despite high variability in biochemical properties among the disease-causing mutants, a proportion of both dismutase-active and -inactive mutants are stably bound to spinal cord mitochondria...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2008-03-11 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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abstract::The c-myc oncogene has been implicated in a wide spectrum of B-cell neoplasias. In normal cells, the level of expression of the c-myc gene correlates with growth status. In the present study, we examined the effect of receptor-mediated inhibition of growth on c-myc expression in a B-cell lymphoma. The murine lymphoma ...
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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abstract::A stable free-radical polymeric derivative of prostaglandin B1 (PGBx) has been synthesized that exhibits regenerative effects on oxidative phosphorylation in aged mitochondria. The molecular weights of the most active preparations fall between 2000 and 2600. PGBx is characterized by a single-line electron spin resonan...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1979-04-01 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:1980-09-01 00:00:00
abstract::Activator-dependent recruitment of TFIID initiates formation of the transcriptional preinitiation complex. TFIID binds core promoter DNA elements and directs the assembly of other general transcription factors, leading to binding of RNA polymerase II and activation of RNA synthesis. How TATA box-binding protein (TBP) ...
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:2006-08-15 00:00:00