Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1995-2-22
pubmed:abstractText
The Escherichia coli CadC protein is required for activation of cadBA transcription under conditions of low external pH and exogenous lysine. cadBA encodes proteins involved in the decarboxylation of lysine to cadaverine, and cadaverine excretion. Sequence analysis suggested that CadC contains a single transmembrane segment separating a DNA-binding domain in the amino terminus from a periplasmic domain. Western analysis of subcellular fractions demonstrated that CadC is expressed and concentrated in the cytoplasmic membrane in cells grown either at an inducing pH (pH 5.8) or at a non-inducing pH (pH 7.6). Eight cadC mutants were isolated based on their ability to confer expression of a cadA-lacZ fusion independent of low external pH or exogenous lysine. Five of these mutants expressed the cadA-lacZ fusion at both pH 5.8 and pH 7.6, but retained the requirement for the lysine signal while the other three mutants displayed pH independence at pH 5.8 but not at pH 7.6. These results support a model in which CadC is a membrane-bound transcriptional activator of the cadBA operon capable of sensing (directly or indirectly) signals generated outside the cytoplasmic membrane as a consequence of acidic pH and lysine.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0950-382X
pubmed:author
pubmed:issnType
Print
pubmed:volume
14
pubmed:geneSymbol
cadA, cadB, cadC
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
7-16
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:7830562-Bacterial Proteins, pubmed-meshheading:7830562-Base Sequence, pubmed-meshheading:7830562-Blotting, Western, pubmed-meshheading:7830562-Carboxy-Lyases, pubmed-meshheading:7830562-Cell Membrane, pubmed-meshheading:7830562-DNA Primers, pubmed-meshheading:7830562-Escherichia coli, pubmed-meshheading:7830562-Genes, Bacterial, pubmed-meshheading:7830562-Hydrogen-Ion Concentration, pubmed-meshheading:7830562-Lysine, pubmed-meshheading:7830562-Molecular Sequence Data, pubmed-meshheading:7830562-Mutagenesis, Site-Directed, pubmed-meshheading:7830562-Operon, pubmed-meshheading:7830562-Phenotype, pubmed-meshheading:7830562-Plasmids, pubmed-meshheading:7830562-Polymerase Chain Reaction, pubmed-meshheading:7830562-Recombinant Fusion Proteins, pubmed-meshheading:7830562-Restriction Mapping, pubmed-meshheading:7830562-Trans-Activators, pubmed-meshheading:7830562-beta-Galactosidase
pubmed:year
1994
pubmed:articleTitle
Altered pH and lysine signalling mutants of cadC, a gene encoding a membrane-bound transcriptional activator of the Escherichia coli cadBA operon.
pubmed:affiliation
Department of Biotechnology, Parke-Davis Pharmaceutical Research, Division of Warner-Lambert Co., Ann Arbor, Michigan 48105.
pubmed:publicationType
Journal Article