Dichloromethane-degrading bacteria in the genomic age.

Dichloromethane (DCM) is a volatile toxic halogenated solvent mainly produced and used industrially. DCM-degrading bacteria have long been models of choice for studying bacterial dehalogenation metabolism at the physiological, biochemical and genetic levels, and have also been used in bioremediation processes. DCM-degrading strains isolated in recent years will be discussed in the context of enzymes known to catalyze dehalogenation of DCM. Insights into the modes of adaptation of bacteria to DCM gained by comparative genomic analysis, highlight the importance of horizontal gene transfer in the dissemination of genes for DCM metabolism in the environment.