Enzymic degradation of bromoxynil by cell-free extracts of Streptomyces felleus.

A method is described for spectrophotometric monitoring the degradation of the herbicide bromoxynil by cell-free extracts of Streptomyces felleus. The method involves a decrease in absorbance at 286 nm (absorption maximum of bromoxynil) that can be ascribed most probably to the cleavage of the aromatic ring of the bromoxynil molecule. Conditions necessary for measuring this degradation together with physico-chemical features of the degradation indicate that the reaction(s) is seemingly catalyzed by an Fe2+-dependent dioxygenase whose activity was not, however, detected in cell-free extracts of a bromoxynil-sensitive mutant of S. felleus as well as other bromoxynil-sensitive streptomycete strains.