Active site mutants show various ampicillin sensitivitiesa

StrainsResult of growth on LB + ampicillin concn (μg/ml) of:
JT272 CPHC+++±
JT357 CPPC++++++++++±±
JT358 CSFC+++++++±
JT359 CPSC+++++++
JT360 CPLC+++++++++
  • a The active site CPHC of wild-type DsbA was mutated to CPPC, CSFC, CPSC, or CPLC. Wild-type E. coli (MG1655) strains carrying a CcrA plasmid and possessing the various chromosomal mutations in the active site of DsbA were streaked onto LB plates containing various concentrations of ampicillin. Sizes of colonies after an overnight incubation at 37°C are denoted as follows: +++, large colonies; ++, medium-sized colonies; +, small colonies; ±, tiny colonies; −, lack of growth.

  • b Growth on LB alone.