Functional genomics of dichloromethane utilization in Methylobacterium extorquens DM4.

摘要: Dichloromethane (CH(2)Cl(2) , DCM) is a chlorinated solvent mainly produced by industry, and common pollutant. Some aerobic methylotrophic bacteria are able to grow with this methane as their sole carbon energy source, using DCM dehalogenase/glutathione S-transferase encoded dcmA transform into two molecules of HCl one molecule formaldehyde, toxic intermediate metabolism. In Methylobacterium extorquens DM4 known genome sequence, lies on 126 kb dcm genomic island not found so far in other DCM-dechlorinating strains. An experimental search for the molecular determinants involved specific cellular responses strain growing was performed. Random mutagenesis minitransposon containing promoterless reporter gfp gene yielded 25 mutants DCM-associated phenotype. Differential proteomic analysis cultures grown methanol defined 38 differentially abundant proteins. The 5.5 islet directly dehalogenation only seven clusters response be localized within island. shown involve core extorquens, providing new insights DCM-dependent adjustments C1 metabolism regulation, suggesting stress during growth DCM. Fatty acid, hopanoid peptidoglycan metabolisms were affected, hinting at membrane-active effects due its properties. A chloride-induced efflux transporter termed CliABC also newly identified. Thus, dechlorination driven elicits complex adaptive dechlorinating well non-dechlorinating