Inhibition of Escherichia coli growth and diaminopimelic acid epimerase by 3-chlorodiaminopimelic acid

Autor: Baumann, R J, Bohme, E H, Wiseman, J S, Vaal, M, Nichols, J S
Zdroj: Antimicrobial Agents and Chemotherapy; August 1988, Vol. 32 Issue: 8 p1119-1123, 5p
Abstrakt: The diaminopimelic acid (DAP) analog, 3-chloro-DAP, was synthesized and tested as the racemic acid for antibacterial activity and for inhibition of DAP epimerase. 3-Chloro-DAP was a potent inhibitor of DAP epimerase purified from Escherichia coli (Ki = 200 nM), and it is argued that 3-chloro-DAP is converted to a tight-binding transition state analog at the active site of this enzyme. Furthermore, 3-chloro-DAP inhibited growth of two E. coli mutants. In one of the mutants known for supersusceptibility to beta-lactams, inhibition was not seen until the mid-log phase of growth, while in the other mutant, a DAP auxotroph, inhibition occurred much earlier. Growth inhibition was reversed by DAP in both strains. In the auxotroph, the reversal was specific for meso-DAP, indicating that DAP epimerase was the target for 3-chloro-DAP. Thus we suggest a novel mechanism of bacterial growth inhibition which depends on DAP epimerase inhibition by a DAP analog.
Databáze: Supplemental Index