Linked Life Data

11797051

Source:http://linkedlifedata.com/resource/pubmed/id/11797051

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2002-1-17
pubmed:abstractText
The Escherichia coli Tat protein export pathway transports folded proteins synthesized with N-terminal twin-arginine signal peptides. Twin-arginine signal sequences contain a conserved SRRxFLK "twin-arginine" amino acid sequence motif which is required for protein export by the Tat pathway. The E. coli trimethylamine N-oxide reductase (TorA) is a Tat-dependent periplasmic molybdoenzyme that facilitates anaerobic respiration with trimethylamine N-oxide as terminal electron acceptor. Here, we describe mutant strains constructed with modified TorA twin-arginine signal peptides. Substitution of the second arginine residue of the TorA signal peptide twin-arginine motif with either lysine or aspartate, or the simultaneous substitution of both arginines with lysine residues, completely abolished export. In each case, the now cytoplasmically localised TorA retained full enzymatic activity with the artificial electron donor benzyl viologen. However, the mutant strains were incapable of anaerobic growth with trimethylamine N-oxide and the non-fermentable carbon-source glycerol. The growth phenotype of the mutant strains was exploited in a genetic screen with the aim of identifying second-site suppressor mutations that allowed export of the modified TorA precursors.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0302-8933
pubmed:author
pubmed:issnType
Print
pubmed:volume
177
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
107-12
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
A genetic screen for suppressors of Escherichia coli Tat signal peptide mutations establishes a critical role for the second arginine within the twin-arginine motif.
pubmed:affiliation
Department of Molecular Microbiology, John Innes Centre, Norwich NR4 7UH, UK.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't