IDENTIFICATION AND CHARACTERIZATION OF ACINETOBACTER SP. CNU961 ABLE TO GROW WITH PHENOL AT HIGH-CONCENTRATIONS

An Acinetobacter sp., strain CNU961, with a higher tolerance to phenol was isolated, and identified through a set of taxonomic studies and a genetic complementation test. Enzymatic and mutagenic studies found t hat the strain dissimilate phenol by hydroxylation to catechol followe d by an ortho-ring cleavage pathway to further mineralize it. The phen ol hydroxylase, which is an inducible enzyme and requires NADPH for op timum activity, was not inhibited by phenol at concentrations up to 0. 5 mM. The different kinetic behaviors of the enzyme activities on NADP H and on phenol reflected that the phenol hydroxylase of strain CNU961 is a multisubunit allosteric enzyme consisting of heterogeneous polyp eptides.