Abstract:
:Swarming bacteria move in multicellular groups and exhibit adaptive resistance to multiple antibiotics. Analysis of this phenomenon has revealed the protective power of high cell densities to withstand exposure to otherwise lethal antibiotic concentrations. We find that high densities promote bacterial survival, even in a nonswarming state, but that the ability to move, as well as the speed of movement, confers an added advantage, making swarming an effective strategy for prevailing against antimicrobials. We find no evidence of induced resistance pathways or quorum-sensing mechanisms controlling this group resistance, which occurs at a cost to cells directly exposed to the antibiotic. This work has relevance to the adaptive antibiotic resistance of bacterial biofilms.
journal_name
Proc Natl Acad Sci U S Aauthors
Butler MT,Wang Q,Harshey RMdoi
10.1073/pnas.0910934107subject
Has Abstractpub_date
2010-02-23 00:00:00pages
3776-81issue
8eissn
0027-8424issn
1091-6490pii
0910934107journal_volume
107pub_type
杂志文章abstract::SoxR is a transcription factor that governs a global defense against the oxidative stress caused by nitric oxide or excess superoxide in Escherichia coli. SoxR is a homodimer containing a pair of [2Fe-2S] clusters essential for its transcriptional activity, and changes in the stability of these metal centers could con...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.93.18.9449
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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
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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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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
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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:2009-06-02 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:2015-05-12 00:00:00