Chloromethane stimulates growth of Methylomicrobium album BG8 on methanol

Abstract Studies were performed to determine if the growth of Methylomicrobium album BG8 on methanol could be enhanced through the provision of chloromethane. M. album BG8 was found to be able to oxidize chloromethane via the particulate methane monooxygenase with an apparent Ks of 11±3 μM and Vmax of 15±0.6 nmol (min mg protein)−1. When up to 2.6 mM chloromethane was provided with 5 mM methanol, methanotrophic growth was significantly enhanced in comparison to the absence of chloromethane, indicating that methanotrophs can utilize chloromethane to support growth, although it could not serve as a sole growth substrate. [14C]chloromethane was found to be oxidized to [14C]CO2 as well as incorporated into biomass. These results indicate that reactions previously thought to be cometabolic may actually provide some benefit to methanotrophs and that these cells can use multiple compounds to enhance growth.