Linked Life Data

17011578

Source:http://linkedlifedata.com/resource/pubmed/id/17011578

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2006-11-19
pubmed:abstractText
Carbon catabolite repression in Bacillus subtilis is carried out mainly by the major regulator CcpA. In contrast, sugar-dependent repression of three genes, sr1 encoding a small untranslated RNA, and two genes, gapB and pckA, coding for gluconeogenic enzymes is mediated by the recently identified transcriptional repressor CcpN. Since previous DNase I footprinting yielded only basic information on the operator sequences of CcpN, chemical interference footprinting studies were performed for a precise contact mapping. Methylation interference, potassium permanganate and hydroxylamine footprinting were used to identify all contacted residues in both strands in the three operator sequences. Furthermore, ethylation interference experiments were performed to identify phosphate residues essential for CcpN binding. Here, we show that each operator has two binding sites for CcpN, one of which was always contacted more strongly than the other. The three sites that exhibited close contacts were very similar in sequence, with only a few slight variations, whereas the other three corresponding sites showed several deviations. Gel retardation assays with purified CcpN demonstrated that the differences in contact number and strength correlated well with significantly different K(D) values for the corresponding single binding sites. However, quantitative DNase I footprinting of whole operator sequences revealed cooperative binding of CcpN that, apparently, compensated the asymmetric contact distribution. Based on these data, possible consequences for the repression mechanism of CcpN are discussed.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0022-2836
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
364
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
434-48
pubmed:dateRevised
2009-7-17
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Transcriptional repressor CcpN from Bacillus subtilis compensates asymmetric contact distribution by cooperative binding.
pubmed:affiliation
AG Bakteriengenetik, Friedrich-Schiller-Universität Jena, Philosophenweg 12, D-07743 Jena, Germany. andreas.licht@uni-jena.de
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't