n-Alkane dissimilation by Rhodopseudomonas sphaeroides transferred OCT plasmid.

The OCT plasmid from Pseudomonas maltophilia N246-1 was transferred to Rhodopseudomonas sphaeroides M1 with very low frequency (1.4-1.9 × 10(-5) per recipient cell at pH 7-8 for a 3-hour reaction time). P. maltophilia N246-1 was able to utilize C8-C14 of n-alkanes, whereas R. gas-liquid chromatography determined that the broad range of carbon numbers of n-alkanes in crude oil was remarkably degraded by the transconjugant, R. sphaeroides M1-C1, compared with donor strain N246-1. The fact that donor and transconjugant strains simultaneously lost the capacity to utilize n-alkanes on L-broth medium suggests that the OCT plasmids are unstable. It was found that the OCT plasmid of P. maltophilia N246 was incompatible with the IncP-2 group of P. aeruginosa KCTC 11245.