A mutation in either dsbA or dsbB, a gene encoding a component of a periplasmic disulfide bond-catalyzing system, is required for high-level expression of the Bacteroides fragilis metallo-beta-lactamase, CcrA, in Escherichia coli.
AUTOR(ES)
Alksne, L E
RESUMO
The metallo-beta-lactamase gene, ccrA, from Bacteroides fragilis is functionally expressed in Escherichia coli only in the presence of a genomic mutation in iarA or iarB (increased ampicillin resistance), identified in this study as dsbA or dsbB, respectively. DsbA and DsbB are components of a periplasmic protein disulfide bond-catalyzing system. Data indicated that DsbA interacted with CcrA, creating aberrant disulfide bond linkages that render CcrA proteolytically unstable. Mutations in dsbA or dsbB permissive for CcrA expression eliminated or greatly reduced DsbA activity, allowing CcrA to assume a disulfide bond-free and proteolytically stable conformation.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=176611Documentos Relacionados
- Dsb-insensitive expression of CcrA, a metallo-beta-lactamase from Bacteroides fragilis, in Escherichia coli after amino acid substitution at two cysteine residues within CcrA.
- Biochemical characterization of the metallo-beta-lactamase CcrA from Bacteroides fragilis TAL3636.
- Purification of metallo-B-lactamase CcrA from Bacteroides fragilis with salting-out method
- Mutational Analysis of the Disulfide Catalysts DsbA and DsbB
- Paradoxical redox properties of DsbB and DsbA in the protein disulfide-introducing reaction cascade
