SEARCH FOR SYSTEMS OF GENETIC EXCHANGE IN METHANE-OXIDIZING BACTERIA

The possibility of transfer and expression of plasmids of the Inc P-1 incompatibility group in cells of obligate methane-oxidizing bacteria Methylomonas rubra 15sh and Methylococcus thermophilus 111p was studie d. Transfer of conjugative plasmids from Escherichia coli and Pseudomo nas putida into cells of two strains of methane-oxidizing bacteria was accomplished. It was ascertained that these plasmids can exist in cel ls of different strains in an autonomous or integrated state. The plas mids studied could be transferred from cells of methane-oxidizing bact eria into E. coli; on some occasions, these plasmids carried chromosom al segments of methane-oxidizing bacteria. Intraspecific gene transfer was demonstrated for the first time in methane-oxidizing bacteria. Th e fundamental possibility of using the Inc P-1 incompatibility group p lasmids as a tool for genetic analysis of Methylococcus thermophilus a nd Methylomonas rubra was shown.