Linked Life Data

8804390

Source:http://linkedlifedata.com/resource/pubmed/id/8804390

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
1996-10-31
pubmed:abstractText
The unorthodox two-component sensor protein BvgS of Bordetella pertussis contains several interesting sequence motifs of unknown functional relevance, such as a histidine motif in its output domain, which is conserved among several unorthodox sensor proteins, a putative nucleotide binding site [Walker box type A] in its linker region, and a region in its periplasmic domain with significant homology to the TonB protein of Escherichia coli. We investigated potential functions of these sequences by constructing B. pertussis strains that express mutant BvgS derivatives. The His1172 residue in the output domain was exchanged for Gln, and the Walker motif was mutated either by the replacement of Lys625 by Arg, or of Gly624 by Val and Lys625 by Leu. To analyse the TonB motif, the periplasmic domain of BvgS was replaced with the corresponding domain of EvgS, an E. coli sensor that is highly homologous to BvgS but lacks the similarity with TonB. All mutations except the conservative Lys/Arg exchange in the Walker box caused the inactivation of BvgS, indicating the functional importance of the conserved motifs. The activity of the mutant proteins could be restored by complementation in trans with various separately expressed, truncated parts of BvgS. Mutations in the BvgS receiver domain could be complemented not only by a construct expressing the wild-type receiver and output domains, but also by the derivative containing the His-Gln exchange. Therefore, the histidine motif, although important for BvgS function, is not essential for complementation of BvgS mutants. The mutations in the Walker box and in the periplasmic domain could be complemented by a truncated BvgS derivative lacking the receiver and output domains. The characterization of a spontaneous revertant of the strain expressing the originally inactive EvgS/BvgS hybrid protein revealed the presence of a mutation in the BvgS linker region, conferring constitutive activity on the protein. As TonB energizes transport processes across the outer membrane of E. coli, the strain expressing the constitutive EvgS/BvgS hybrid protein lacking the TonB motif was used in preliminary investigations of a possible direct involvement of BvgS in transport processes.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0026-8925
pubmed:author
pubmed:issnType
Print
pubmed:day
27
pubmed:volume
252
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
169-76
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:8804390-Amino Acid Sequence, pubmed-meshheading:8804390-Bacterial Proteins, pubmed-meshheading:8804390-Blotting, Western, pubmed-meshheading:8804390-Bordetella pertussis, pubmed-meshheading:8804390-Chromosome Mapping, pubmed-meshheading:8804390-Cloning, Molecular, pubmed-meshheading:8804390-Conserved Sequence, pubmed-meshheading:8804390-Fimbriae, Bacterial, pubmed-meshheading:8804390-Genetic Complementation Test, pubmed-meshheading:8804390-Histidine, pubmed-meshheading:8804390-Molecular Sequence Data, pubmed-meshheading:8804390-Mutagenesis, Site-Directed, pubmed-meshheading:8804390-Mutation, pubmed-meshheading:8804390-Phenotype, pubmed-meshheading:8804390-Plasmids, pubmed-meshheading:8804390-Signal Transduction, pubmed-meshheading:8804390-Transcription Factors, pubmed-meshheading:8804390-Virulence Factors, Bordetella
pubmed:year
1996
pubmed:articleTitle
Conserved sequence motifs in the unorthodox BvgS two-component sensor protein of Bordetella pertussis.
pubmed:affiliation
Lehrstuhl für Mikrobiologie, Theodor-Boveri-Institut für Biowissenschaften (Biozentrum) der Universität Würzburg, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't