PMID:2607970
| Citation |
No author listed (1989) Regulation of enterobacterial cephalosporinase production: the role of a membrane-bound sensory transducer. Mol. Microbiol. 3:1121-30 |
|---|---|
| Abstract |
In clinical isolates of Enterobacter cloacae, resistance to the newer beta-lactam antibiotics often results from overproduction of a cephalosporinase encoded by the beta-lactam-inducible ampC gene. Regulation of ampC is controlled by the divergently expressed activator gene, ampR, and a second unlinked locus. In this presentation we show that although Escherichia coli has lost its ampR gene it has retained the second regulatory locus and that this comprises the bicistronic ampDE operon. Genetic and biochemical studies define the ampD gene as encoding a repressor for ampC transcription whereas the ampE gene product is a cytoplasmic membrane protein. Inactivation of the AmpD protein by mutation causes massive overproduction of cephalosporinase which, in E. cloacae, can terminate in therapeutic failure. In contrast, loss of AmpE results in a total block in induction, despite the presence of the activator, AmpR. |
| Links | |
| Keywords |
Amino Acid Sequence; Ampicillin/pharmacology; Bacterial Proteins/genetics; Base Sequence; Cephalosporinase/biosynthesis; Cephalosporinase/genetics; Cloning, Molecular; Enterobacter/enzymology; Enterobacter/genetics; Enterobacteriaceae/enzymology; Gene Expression Regulation, Enzymologic; Genes, Bacterial; Genes, Regulator; Membrane Proteins/genetics; Molecular Sequence Data; Mutation; Nucleic Acid Hybridization; Operon; Plasmids; RNA, Messenger; Restriction Mapping; Signal Transduction; Transcription, Genetic; Transformation, Bacterial; beta-Lactamases/biosynthesis |
| edit table |
Significance
You can help EcoliWiki by summarizing why this paper is useful
Useful Materials and Methods
You can help Ecoliwiki by describing the useful materials (strains, plasmids, antibodies, etc) described in this paper.
Annotations
| Gene product | Qualifier | GO ID | GO term name | Evidence Code | with/from | Aspect | Notes | Status |
|---|---|---|---|---|---|---|---|---|
| edit table |
EcoliWiki Links
Add links to pages that link here (e.g. gene, product, method pages)
References
See Help:References for how to manage references in EcoliWiki.