MINERALIZATION OF 4-CHLORODIBENZOFURAN BY A CONSORTIUM CONSISTING OF SPHINGOMONAS SP STRAIN RW1 AND BURKHOLDERIA SP STRAIN JWS

The dibenzofuran-degrading bacterium Sphingomonas sp. strain RW1 (R.-M . Wittich, H. Wilkes, V. Sinnwell, W. Francke, and P. Fortnagel, Appl. Environ. Microbiol. 58:1005-10101 1992) attacks 4-chlorodibenzofuran on the unsubstituted aromatic ring via distal dioxygenation adjacent t o the ether bridge to produce 3'-chloro-2,2',3-trihydroxybiphenyl, whi ch ct as identified by nuclear magnetic resonance spectroscopy and mas s spectrometry. The compound is subsequently meta cleaved, and the res pective intermediate is hydrolyzed to form a C-5 moiety. Which is furt her degraded to Krebs cycle intermediates and to 3-chlorosalicylate. T his dead-end product is released into the culture medium. A coculture of strain RW1 and the 3,5-dichlorosalicylate-degrading strain Burkhold eria sp. strain JWS (A. Schindowski, R.-M. Wittich, and P. Fortnagel, FEMS Microbial. Lett. 8-1:63-70, 1991) is able to completely degrade 4 -chlorodibenzofuran with concomitant release of Cl- and formation of b iomass.