title: Plasmid analysis and cloning of the dichloromethane-utilization genes of Methylobacterium sp. DM4.
abstract: The dichloromethane (DCM)-utilizing facultative methylotroph Methylobacterium sp. DM4 was shown to contain three plasmids with approximate size of 120 kb, 40 kb and 8 kb. Curing experiments suggested that the DCM-utilization character was correlated with the possession of an intact 120 kb plasmid. The DCM-utilization genes were cloned on the broad-host-range vector pVK100. Plasmid pME1510, a recombinant plasmid carrying a 21 kb HindIII fragment complemented DCM-utilization-negative derivatives of Methylobacterium sp. DM4 and conferred the DCM-utilization-positive phenotype to a number of Gram-negative methylotrophic bacteria. In Southern hybridization experiments with pMe1510 as a probe, chromosomal DNA from Methylobacterium sp. DM4 gave definite signals while purified plasmid DNA did not. Plasmid pME1510 did not hybridize with total DNA from a cured DCM-non-utilizing derivative of Methylobacterium sp. DM4. It is concluded that the DCM-utilization genes are located on the chromosome or on a megaplasmid. Curing procedures thus led to the formation of a chromosomal or megaplasmid deletion larger than 21 kb and covering the DCM-utilization genes or to the loss of an undetected megaplasmid.
mesh_terms: D002876:Chromosomes, Bacterial; D003001:Cloning, Molecular; D005798:Genes, Bacterial; D008752:Methylene Chloride / Q000378:metabolism; D008772:Methylococcaceae / Q000235:genetics* / Q000378:metabolism; D009693:Nucleic Acid Hybridization; D010957:Plasmids
chemical_list: D008752:Methylene Chloride