Biodegradation pathway of 2-chlorodibenzo-p-dioxin and 2-chlorodibenzofuran in the biphenyl-utilising strain JB1

The biphenyl-utilising Burkholderia (previously Alcaligenes) strain JB1 is also able to degrade a number of chlorinated dibenzo-p-dioxins and dibenzofurans. In this study, 4-chlorocatechol and a chlorotrihydroxydiphenyl ether were identified as metabolites of 2-chlorodibenzo-p-dioxin. 5-Chlorosalicylic acid and a chlorotrihydroxybiphenyl were metabolites of 2-chlorodibenzofuran. These results show that degradation of these compounds follows pathways in which the initial reaction is angular dioxygenation, followed by cleavage of an ether bridge. This pathway is similar to that used by dibenzofuran-degrading strains such as Sphingomonas sp. strain RW1.