FIG. 5.

Proposed benzene degradation pathway with chlorate as the electron acceptor in strain BC and proposed stoichiometric reactions involved in benzene degradation with chlorate as the electron acceptor in strain BC. [H] indicates reducing equivalents. Benzene metabolism involves the hydroxylation of benzene to phenol, phenol hydroxylation to catechol, extradiol (meta) cleavage of catechol to 2-hydroxymuconic semialdehyde (2-hms), and complete oxidation of 2-hydroxymuconic semialdehyde to carbon dioxide and reducing equivalents. Chlorate metabolism involves the reduction of chlorate to chlorite, dismutation of chlorite into chloride and oxygen, and subsequent reduction of oxygen to water.