Abstract：
:Legionella pneumophila can replicate inside amoebae and also alveolar macrophages to cause Legionnaires' Disease in susceptible hosts. When nutrients become limiting, a stringent-like response coordinates the differentiation of L. pneumophila to a transmissive form, a process mediated by the two-component system LetA/S and the sigma factors RpoS and FliA. Here we demonstrate that the broadly conserved RNA binding protein CsrA is a global repressor of L. pneumophila transmission phenotypes and an essential activator of intracellular replication. By analysing csrA expression and the phenotypes of csrA single and double mutants and a strain that expresses csrA constitutively, we demonstrate that, during replication in broth, CsrA represses every post-exponential phase phenotype examined, including cell shape shortening, motility, pigmentation, stress resistance, sodium sensitivity, cytotoxicity and efficient macrophage infection. At the transition to the post-exponential phase, LetA/S relieves CsrA repression to induce transmission phenotypes by both FliA-dependent and -independent pathways. For L. pneumophila to avoid lysosomal degradation in macrophages, CsrA repression must be relieved by LetA/S before phagocytosis; conversely, before intracellular bacteria can replicate, CsrA repression must be restored. The reciprocal regulation of replication and transmission exemplified by CsrA likely enhances the fitness of microbes faced with fluctuating environments.
journal_name
Mol Microbioljournal_title
Molecular microbiologyauthors
Molofsky AB,Swanson MSdoi
10.1046/j.1365-2958.2003.03706.xsubject
Has Abstractpub_date
2003-10-01 00:00:00pages
445-61issue
2eissn
0950-382Xissn
1365-2958pii
3706journal_volume
50pub_type
杂志文章abstract：:Gram-negative bacteria survive harmful environmental stressors by modifying their outer membrane. Much of this protection is afforded upon remodeling of the lipid A region of the major surface molecule lipopolysaccharide (LPS). For example, the addition of cationic substituents, such as 4-amino-4-deoxy-L-arabinose (L-...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/mmi.13018
更新日期：2015-07-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.1994.tb00426.x
更新日期：1994-07-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.1990.tb02014.x
更新日期：1990-01-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1046/j.1365-2958.2001.02489.x
更新日期：2001-07-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.1993.tb01714.x
更新日期：1993-08-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1046/j.1365-2958.2003.03908.x
更新日期：2004-03-01 00:00:00
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pub_type： 杂志文章
doi：10.1111/j.1365-2958.1993.tb01135.x
更新日期：1993-02-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1046/j.1365-2958.2000.02152.x
更新日期：2000-11-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章,评审
doi：10.1111/j.1365-2958.2008.06224.x
更新日期：2008-06-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
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更新日期：1997-01-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1046/j.1365-2958.2002.02805.x
更新日期：2002-02-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.2005.04957.x
更新日期：2006-01-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1046/j.1365-2958.2000.02178.x
更新日期：2000-11-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.2004.04037.x
更新日期：2004-05-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/mmi.13024
更新日期：2015-07-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1046/j.1365-2958.2001.02517.x
更新日期：2001-07-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.2007.06027.x
更新日期：2008-02-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.2005.04918.x
更新日期：2005-11-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1046/j.1365-2958.2002.03085.x
更新日期：2002-08-01 00:00:00
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pub_type： 杂志文章
doi：10.1046/j.1365-2958.2003.03909.x
更新日期：2004-03-01 00:00:00
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pub_type： 杂志文章
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更新日期：1999-07-01 00:00:00
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pub_type： 杂志文章
doi：10.1046/j.1365-2958.2001.02356.x
更新日期：2001-04-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1046/j.1365-2958.2003.03907.x
更新日期：2004-02-01 00:00:00
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pub_type： 杂志文章
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更新日期：2007-12-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1046/j.1365-2958.2002.02938.x
更新日期：2002-05-01 00:00:00
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journal_title：Molecular microbiology
pub_type：
doi：10.1111/mmi.12016
更新日期：2012-11-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 评论,杂志文章
doi：10.1111/j.1365-2958.2010.07380.x
更新日期：2010-11-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.2010.07060.x
更新日期：2010-03-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1046/j.1365-2958.2001.02603.x
更新日期：2001-09-01 00:00:00
abstract：:Two operons, comAB and comCDE, play a key role in the co-ordination of spontaneous competence development in cultures of Streptococcus pneumoniae. ComAB is required for export of the comC-encoded competence-stimulating peptide (CSP). Upon CSP binding, the histidine kinase ComD activates ComE, its cognate response regu...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1046/j.1365-2958.2000.02187.x
更新日期：2000-11-01 00:00:00
