Influence of substrate concentration on the induction of amidases in herbicide degradation

Two bacteria which are able to hydrolyze phenylamide herbicides show differences in the induction of amidases at very low inducer concentrations. In the strain 28/1 no amidase activity could be found at inducer concentrations below 0.01 to 0.05 mm in dependence on the inducer. In the strain Rhodococcus spec. b3 a low level of a constitutive amidase was observed. With increasing inducer concentration from 0.001 to 0.5 mm an increasing amidase activity was measured.