Desulfitobacterium hafniense DCB-2 DSM 10664

The Desulfitobacterium genus was discovered in the last decade, but has already become recognized as one of the two most important groups of anaerobic dehalogenating bacteria. Members of this genus dechlorinate both aromatic and alkyl chlorinated compounds including some of the most problematic pollutants, e.g. chlorinated phenols, chlorinated ethenes (widely used solvents) and there is suggestive evidence that they may also dechlorinate polychlorinated biphenyls (PCBs). They are gram positive, of low G+C content, spore-forming bacteria and represent a lineage for which no other genome has been sequenced. The strain being sequenced, Desulfitobacterium hafniense strain DCB-2, grows by chlororespiration on a chlorinated phenolic compounds. The protein responsible for dechlorination has been purified. There is suggestive evidence that the genome of D. hafniense encodes several reductive dehalogenase-like genes. Determination of the sequences of these genes will aid in understanding the substrate ranges of the dehalogenases and the regulation of gene expression. The sequence should also shed light on the origin of the dehalogenase genes since they share a similarity with the family of perchlorethene reductive dehalogenases found in other distantly related bacteria.