MppA, a periplasmic binding protein essential for import of the bacterial cell wall peptide L-alanyl-gamma-D-glutamyl-meso-diaminopimelate.

ABSTRACT: Mutants of a diaminopimelic acid (Dap)-requiring strain of Escherichia coli were isolated which failed to grow on media in which Dap was replaced by the cell wall murein tripeptide, L-alanyl-gamma-D-glutamyl-mesodiaminopimelate. In one such mutant, which is oligopeptide permease (Opp) positive, we have identified a new gene product, designated MppA (murein peptide permease A), that is about 46% identical to OppA, the periplasmic binding protein for Opp. A plasmid carrying the wild-type mppA gene allows the mutant to grow on tripeptide. Two other mutants that failed to grow on tripeptide were resistant to triornithine toxicity, indicating a defect in the opp operon. An E. coli strain whose entire opp operon was deleted but which carried the mppA locus was unable to grow on murein tripeptide

SUBMITTER: Park JT 

PROVIDER: S-EPMC107010 | biostudies-literature | 1998 Mar

REPOSITORIES: biostudies-literature