INITIAL REACTIONS IN ANAEROBIC ETHYLBENZENE OXIDATION BY A DENITRIFYING BACTERIUM, STRAIN EB1

Initial reactions in anaerobic oxidation of ethylbenzene were investig ated in a denitrifying bacterium, strain EB1, Cells of strain EB1 mine ralized ethylbenzene to CO2 under denitrifying conditions, as demonstr ated by conversion of 69% of [C-14]ethylbenzene to (CO2)-C-14, In anae robic suspensions of strain EB1 cells metabolizing ethylbenzene, the t ransient formation and consumption of 1-phenylethanol, acetophenone, a nd an as yet unidentified compound were observed, On the basis of grow th experiments and spectroscopic data, the unknown compound is propose d to be benzoyl acetate, Cell suspension experiments using (H2O)-O-18 demonstrated that the hydroxyl group of the first product of anoxic et hylbenzene oxidation, 1-phenylethanol, is derived from water, A tentat ive pathway for anaerobic ethylbenzene mineralization by strain EB1 is proposed.