Bioinformatics, bacterial expression and enzyme activity analyses of dichloromethane dehalogenase from Methylobacterium rhodesianum H13

Identification of dcmR, the regulatory gene governing expression of dichloromethane dehalogenase in Methylobacterium sp. strain DM4.

The genes for dichloromethane utilization by Methylobacterium sp. strain DM4 are encoded on a 2.8-kb sequenced DNA fragment, the dcm region. This fragment contains dcmA, the structural gene of dichloromethane dehalogenase and, upstream of dcmA, a 1.5-kb region responsible for inducibility of dichloromethane dehalogenase by dichloromethane. A fragment of the dcm region covering dcmA and 230 bp o...

Dichloromethane dehalogenase with improved catalytic activity isolated from a fast-growing dichloromethane-utilizing bacterium.

A methylotrophic bacterium, denoted strain DM11, was isolated from groundwater and shown to utilize dichloromethane or dibromomethane as the sole carbon and energy source. The new isolate grew at the high rate of 0.22 h-1 compared with 11 previously characterized dichloromethane-utilizing bacteria (micromax, 0.08 h-1). The dichloromethane dehalogenase from strain DM11 (group B enzyme) was purif...

Effects of bacterial host and dichloromethane dehalogenase on the competitiveness of methylotrophic bacteria growing with dichloromethane.

Methylobacterium sp. strain DM4 and Methylophilus sp. strain DM11 can grow with dichloromethane (DCM) as the sole source of carbon and energy by virtue of homologous glutathione-dependent DCM dehalogenases with markedly different kinetic properties (the kcat values of the enzymes of these strains are 0.6 and 3.3 S-1, respectively, and the Km values are 9 and 59 microM, respectively). These stra...

Growth inhibition of Escherichia coli by dichloromethane in cells expressing dichloromethane dehalogenase/glutathione S-transferase.

Dichloromethane (DCM) dehalogenase converts DCM to formaldehyde via the formation of glutathione metabolites and generates 2 mol HCl per mol DCM metabolized. Growth of Escherichia coli expressing DCM dehalogenase was immediately and severely inhibited during conversion of 0.3 mM DCM. Intracellular pH (pH(i)) rapidly decreased and chloride ions were steadily released into the medium. Bacterial g...

optimization of bacterial urate oxidase enzyme activity