[Functional analysis of the genome fragment involved in aerobic dichloromethane degradation by methylobacterium dichloromethanicum DM4].

The hypothetical genes of Methylobacterium dichloromethanicum DM4, METDI 2671 (bioD2), and METDI 2680 located within the chromosomal fragment (126 kb) associated with dichloromethane (DCM) degradation have been studied. The reverse transcription polymerase chain reaction method (RT-PCR) showed the presence of transcripts of both genes in cells grown on DCM and methanol. The mobilized suicidal vector pK18mob was used to obtain knockout mutants in these genes. The BIO mutant (with an insertion in the bioD2 gene) after cultivation on methanol was characterized by a lower growth rate on DCM compared to the wild-type DM4 strain, while the MT mutant (with an insertion in the METDI 2680 gene) did not differ from the initial strain in respect of these characteristics. The results demonstrate the involvement of the bioD2 gene in biotin biosynthesis coupled with DCM degradation.