Linked Life Data

11918818

Source:http://linkedlifedata.com/resource/pubmed/id/11918818

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2002-3-28
pubmed:abstractText
The utilization of organosulphur compounds as sources of sulphur by Escherichia coli is strongly repressed by sulphate. To search for the signal enabling E. coli to alternate gene expression according to the sulphur source, we investigated the transcriptional control of the ssuEADCB operon, required for the transport and desulphonation of aliphatic sulphonates. We demonstrate that, of the two LysR-type regulators involved in expression from the ssu promoter, Cbl acts as a direct and sufficient activator of transcription in vivo and in vitro, whereas CysB downregulates the promoter efficiency. Most importantly, the Cbl-mediated transcription initiation at the ssu promoter in vitro is abolished in the presence of an early metabolite of the sulphate assimilatory pathway, adenosine 5'-phosphosulphate (APS). This role for APS was confirmed in vivo by measuring the expression of beta-galactosidase from a transcriptional ssu-lacZ fusion in strains containing different mutations blocking the synthesis and consumption of APS. Our data comprise the first evidence that APS may act as the negative cofactor of the transcriptional regulator Cbl, and that APS, and not sulphate itself, serves as the signalling molecule for sulphate excess.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0950-382X
pubmed:author
pubmed:issnType
Print
pubmed:volume
43
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1347-58
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
The switch from inorganic to organic sulphur assimilation in Escherichia coli: adenosine 5'-phosphosulphate (APS) as a signalling molecule for sulphate excess.
pubmed:affiliation
Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5A, 02-106 Warsaw, Poland.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't