Mineralization of 4-chlorodibenzofuran by a consortium consisting of Sphingomonas sp. strain RW1 and Burkholderia sp. strain JWS

Abstract

The dibenzofuran-degrading bacterium Sphingomonas sp. strain RW1 (R.-M. Wittich, H. Wilkes, V. Sinnwell, W. Francke, and P. Fortnagel, Appl. Environ. Microbiol. 58:1005-1010, 1992) attacks 4-chlorodibenzofuran on the unsubstituted aromatic ring via distal dioxygenation adjacent to the ether bridge to produce 3'-chloro-2,2',3-trihydroxybiphenyl, which was identified by nuclear magnetic resonance spectroscopy and mass spectrometry. The compound is subsequently meta cleaved, and the respective intermediate is hydrolyzed to form a C-5 moiety, which is further degraded to Krebs cycle intermediates and to 3-chlorosalicylate. This dead-end product is released into the culture medium. A coculture of strain RW1 and the 3,5- dichlorosalicylate-degrading strain Burkholderia sp. strain JWS (A. Schindowski, R.-M. Witrich, and P. Fortnagel, FEMS Microbiol. Lett. 84:63- 70, 1991) is able to completely degrade 4-chlorodibenzofuran with concomitant release of CI- and formation of biomass.