ENVIRONMENTAL CONTROLS ON BACTERIAL LIPID PRODUCTION BY A METHANOTROPH-METHYLOTROPH CO-CULTURE

Summary Methane-oxidizing bacteria regulate the natural release of methane, however, the role of aerobic methane oxidation in the geologic record is poorly constrained. Our study evaluates potential biomarkers for methane-oxidizing bacteria by assessing the environmental controls on bacteriohopanepolyol (BHP) production by a Type I methanotroph, Methylobacter sp. We also evaluate the partnership of Methylobacter sp. with a methylotroph, Methylotenera, sp., which is known to co-occur with methanotrophs and is thought to play a role in enhancing methane oxidation rates. We set up incubation experiments for an enrichment co-culture of Methylobacter sp. and Methylotenera sp. to evaluate how temperature, methane concentrations, and salinity influence (1) the culture’s lipidome (specifically BHPs), (2) the community composition, and (3) methane oxidation rates.