Abstract：
:Pseudomonas fluorescens Pf-5, a rhizosphere-inhabiting bacterium that suppresses several soilborne pathogens of plants, produces the antibiotics pyrrolnitrin, pyoluteorin, and 2,4-diacetylphloroglucinol. A gene necessary for pyrrolnitrin production by Pf-5 was identified as rpoS, which encodes the stationary-phase sigma factor sigma s. Several pleiotropic effects of an rpoS mutation in Escherichia coli also were observed in an RpoS- mutant of Pf-5. These included sensitivities of stationary-phase cells to stresses imposed by hydrogen peroxide or high salt concentration. A plasmid containing the cloned wild-type rpoS gene restored pyrrolnitrin production and stress tolerance to the RpoS- mutant of Pf-5. The RpoS- mutant overproduced pyoluteorin and 2,4-diacetyl-phloroglucinol, two antibiotics that inhibit growth of the phytopathogenic fungus Pythium ultimum, and was superior to the wild type in suppression of seedling damping-off of cucumber caused by Pythium ultimum. When inoculated onto cucumber seed at high cell densities, the RpoS- mutant did not survive as well as the wild-type strain on surfaces of developing seedlings. Other stationary-phase-specific phenotypes of Pf-5, such as the production of cyanide and extracellular protease(s) were expressed by the RpoS- mutant, suggesting that sigma s is only one of the sigma factors required for the transcription of genes in stationary-phase cells of P. fluorescens. These results indicate that a sigma factor encoded by rpoS influences antibiotic production, biological control activity, and survival of P. fluorescens on plant surfaces.
journal_name
Proc Natl Acad Sci U S Aauthors
Sarniguet A,Kraus J,Henkels MD,Muehlchen AM,Loper JEdoi
10.1073/pnas.92.26.12255subject
Has Abstractpub_date
1995-12-19 00:00:00pages
12255-9issue
26eissn
0027-8424issn
1091-6490journal_volume
92pub_type
杂志文章abstract：:The mammalian RNase A superfamily comprises a diverse array of ribonucleolytic proteins that have a variety of biochemical activities and physiological functions. Two rapidly evolving RNases of higher primates are of particular interest as they are major secretory proteins of eosinophilic leukocytes and have been foun...
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.080071397
更新日期：2000-04-25 00:00:00
abstract：:Homozygous lymphoblastoid cell lines representing Dw subtypes of the DR2 serotype were studied for structural polymorphism at DR beta. These subtypes included Dw2, Dw12, and non-Dw2/non-Dw12. Analysis by two-dimensional gel electrophoresis showed that two DR beta genes were expressed in each cell line studied. One of ...
journal_title：Proceedings of the National Academy of Sciences of the United States of America
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doi：10.1073/pnas.84.13.4591
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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.90.1.75
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journal_title：Proceedings of the National Academy of Sciences of the United States of America
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doi：10.1073/pnas.96.1.109
更新日期：1999-01-05 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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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.97.24.13286
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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.92.5.1510
更新日期：1995-02-28 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：2003-08-19 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：1975-06-01 00:00:00
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更新日期：2006-09-05 00:00:00
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pub_type： 杂志文章
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更新日期：2008-03-18 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.0802597105
更新日期：2008-08-12 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.73.7.2458
更新日期：1976-07-01 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
doi：10.1073/pnas.0308652100
更新日期：2004-02-17 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.76.4.1613
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
pub_type： 杂志文章
doi：10.1073/pnas.81.8.2484
更新日期：1984-04-01 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：2011-05-10 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.1408018111
更新日期：2014-07-01 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：2005-04-05 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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journal_title：Proceedings of the National Academy of Sciences of the United States of America
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更新日期：2001-02-13 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：2017-10-03 00:00:00
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doi：10.1073/pnas.0511344103
更新日期：2006-02-28 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.85.12.4355
更新日期：1988-06-01 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
doi：10.1073/pnas.0406098101
更新日期：2004-12-14 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.84.13.4418
更新日期：1987-07-01 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：1998-05-26 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.80.9.2524
更新日期：1983-05-01 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
doi：10.1073/pnas.0702623104
更新日期：2007-05-08 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.78.4.2562
更新日期：1981-04-01 00:00:00
