Abstract:
:Sensory adaptation of low-abundance chemoreceptors in Escherichia coli requires assistance from high-abundance receptors, because only high-abundance receptors carry the carboxyl-terminal pentapeptide sequence NWETF that enhances adaptational covalent modification. Using membrane vesicles containing both high-abundance receptor Tar and low-abundance receptor Trg, we observed effective assistance in vitro for all three adaptational modifications: methylation, demethylation and deamidation. These results demonstrated that adaptational assistance involves not only the previously documented assistance for methylation but also assistance for the two CheB-catalysed reactions. We determined rates of assisted methylation and demethylation at many ratios of assisting to assisted receptor. Analysis by a model of assistance indicated one Tar dimer could assist seven Trg dimers in methylation or five in demethylation, defining assistance neighbourhoods. These neighbourhoods were larger than a trimer of homodimers, required only receptors and were minimally affected by formation of signalling complexes. Time courses of assisted Trg methylation in membranes with low amounts of Tar showed that assisting receptors did not diffuse beyond initial neighbourhoods for at least two hours. Taken together, these observations indicate that chemoreceptors can form stable neighbourhoods larger than trimers in the absence of other chemotaxis proteins. Such interactions are likely to occur in natural receptor clusters in vivo.
journal_name
Mol Microbioljournal_title
Molecular microbiologyauthors
Li M,Hazelbauer GLdoi
10.1111/j.1365-2958.2005.04641.xsubject
Has Abstractpub_date
2005-06-01 00:00:00pages
1617-26issue
6eissn
0950-382Xissn
1365-2958pii
MMI4641journal_volume
56pub_type
杂志文章abstract::The Gram-negative bacterium Vibrio cholerae is the infectious agent responsible for the disease Asiatic cholera. The genes required for V. cholerae virulence, such as those encoding the cholera toxin (CT) and toxin-coregulated pilus (TCP), are controlled by a cascade of transcriptional activators. Ultimately, the dire...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2005.04589.x
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abstract::The gltX gene, encoding the glutamyl-tRNA synthetase (GluRS), and the valU operon, whose transcripts contain three tRNAVal/UAC and one tRNALys/UUU, are adjacent and divergently transcribed. It is the only known case of adjacent genes encoding an aminoacyl-tRNA synthetase and a tRNA precursor in Escherichia coli. The g...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.1998.00745.x
更新日期:1998-03-01 00:00:00
abstract::SigD and SigE (Salmonella invasion gene) are proteins needed for optimal invasion of Salmonella typhimurium into eukaryotic cells in vitro. SigD is a secreted protein and SigE is a putative chaperone required for SigD stability and/or secretion. SigD is secreted by a type III secretion apparatus encoded within a patho...
journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1046/j.1365-2958.2000.01772.x
更新日期:2000-02-01 00:00:00
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pub_type: 杂志文章,评审
doi:10.1111/mmi.14633
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journal_title:Molecular microbiology
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journal_title:Molecular microbiology
pub_type: 杂志文章
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pub_type: 杂志文章,评审
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更新日期:2004-09-01 00:00:00
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journal_title:Molecular microbiology
pub_type: 杂志文章
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journal_title:Molecular microbiology
pub_type: 杂志文章
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更新日期:1998-07-01 00:00:00
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pub_type: 杂志文章,评审
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journal_title:Molecular microbiology
pub_type: 评论,杂志文章
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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/j.1365-2958.2007.06016.x
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:10.1111/j.1365-2958.2009.06641.x
更新日期:2009-04-01 00:00:00
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journal_title:Molecular microbiology
pub_type: 杂志文章,评审
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更新日期:2012-08-01 00:00:00
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journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.2010.07291.x
更新日期:2010-09-01 00:00:00
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journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.1993.tb01660.x
更新日期:1993-06-01 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:1999-07-01 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:2011-05-01 00:00:00
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pub_type: 杂志文章
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更新日期:2004-02-01 00:00:00
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更新日期:2010-08-01 00:00:00
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pub_type: 杂志文章
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journal_title:Molecular microbiology
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更新日期:2011-09-01 00:00:00
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pub_type: 杂志文章
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更新日期:2002-10-01 00:00:00
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pub_type: 杂志文章
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更新日期:2008-10-01 00:00:00
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journal_title:Molecular microbiology
pub_type: 杂志文章,评审
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更新日期:2014-10-01 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:1992-05-01 00:00:00