[Phenol degradation by Rhodococcus opacus strain 1G].

During cultivation in a liquid medium, the bacterium Rhodococcus opacus 1G was capable of growing on phenol at a concentration of up to 0.75 g/l. Immobilization of Rhodococcus opacus 1G had a positive effect on cell growth in the presence of phenol at high concentrations. The substrate at concentrations of 1.0 and 1.5 g/l was completely utilized over 24 and 48 h, respectively. The key enzymes of phenol degradation (two pyrocatechol 1,2-dioxygenases and muconate cycloisomerase) were isolated. One of the dioxygenases was very unstable. By substrate specificity, another enzyme belonged to pyrocatechol 1,2-dioxygenases of the classical ortho-pathway. Chloropyrocatechols and chlorophenols served as competitive antagonists of pyrocatechol 1,2-dioxygenases. The inhibitory effect of other aromatic compounds was less significant. Our results suggest that this strain holds promise for bioremediation of phenol wastewater.