Kinetics and regulation of beta-lactamase formation in methylotrophic bacterium

The regulation and kinetics of formation of an inducible, cell-bound oxacillin-hydrolyzing beta-lactamase (M-OXA) by a methanol-grown Pseudomonas strain were investigated in batch, chemostat, and two-stage continuous cultures. The extent to which enzyme production occurs declines at increased growth rates, and the rate of M-OXA beta-lactamase production follows a kinetic pattern that is partially growth independent and partially inversely growth linked. Growth and enzyme formation are regulated differently by medium constituents. The initial steps of M-OXA beta-lactamase synthesis takes place during the exponential growth phase, and active enzyme is produced by induced nonproliferating cells, probably through a turnover mechanism.