Linked Life Data

11065366

Source:http://linkedlifedata.com/resource/pubmed/id/11065366

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:dateCreated
2001-1-11
pubmed:abstractText
In the complete genome sequence of the cyanobacterium SYNECHOCYSTIS: sp. strain PCC 6803 [Kaneko et al. (1996 ). DNA Res 3, 109-136] genes were identified encoding putative group 3 sigma-factors SigH (Sll-0856), SigG (Slr-1545) and SigF (Slr-1564) and the regulatory protein RsbU (Slr-2031). Mutations in these genes were generated by interposon mutagenesis to study their importance in stress acclimation. For the genes sigH, sigF and rsbU, the loci segregated completely. However, attempts to mutagenize the sigG locus resulted in merodiploids. Under standard growth conditions only minor differences were detected between the mutants and wild-type. However, cells of the RsbU mutant showed a clear defect in regenerating growth after a nitrogen- and sulphur-starvation-induced stationary phase. After applying salt, heat and high-light shocks, stress protein synthesis was analysed by means of one- and two-dimensional electrophoresis. Cells of the SigF mutant showed a severe defect in the induction of salt stress proteins. Although the acclimation to moderate salt stress up to 684 mM NaCl was not significantly changed in this mutant, its ability to acclimate to higher concentrations of NaCl was reduced. Northern blot experiments showed a constitutive expression of the rsbU and sigF genes. The expression of the sigH gene was found to be stress-stimulated, particularly in heat-shocked cells, whilst that of sigG was transiently decreased under stress conditions. Possible functions of these regulatory proteins in stress acclimation of Synechocystis cells are discussed.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
1350-0872
pubmed:author
pubmed:issnType
Print
pubmed:volume
146 ( Pt 11)
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2877-89
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Stress responses of Synechocystis sp. strain PCC 6803 mutants impaired in genes encoding putative alternative sigma factors.
pubmed:affiliation
Universität Rostock, FB Biologie, Institut für Molekulare Physiologie und Biotechnologie, Doberaner Str. 143,D-18051 Rostock, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't