Quantification of methanotrophic metabolism
Methanotrophic bacteria are a group of prokaryotes capable of using methane as their sole carbon and energy source. Although efforts have been made to simulate and elucidate their metabolism via computational approaches or 13C tracer analysis, major gaps still exist in our understanding of methanotrophic metabolism at the systems level. Particularly, direct measurements of system-wide fluxes are required to understand metabolic network function. To experimentally quantify metabolism of one-carbon substrates in RuMP cycle methanotrophs, 13C isotopically nonstationary metabolic flux analysis (INST-MFA) is currently the only viable approach. By using this technique, we have quantified metabolism of a type I methanotroph, Methylotuvimicrobium buryatense 5GB1C, in response to different growth conditions. Our quantitative insights into the methanotrophic carbon and energy metabolism will pave the way for future flux analysis studies and set the stage for rational design of methanotrophic strains for industrial applications. Further, the experimental strategies can be applied to other methane or methanol utilizers, and the results will offer a unique and quantitative perspective of diverse methylotrophic metabolism.
