Hydrogen utilization by Methylocystis sp. strain SC2 expands the known metabolic versatility of type IIa methanotrophs

The objective of this study was to assess whether Methylocystis sp. strain SC2, as a representative for Methylocystis spp., can utilize hydrogen to optimize the biomass yield by mixed utilization of CH4 and H2, rather than CH4 as the sole source of energy. Thus, we aimed to show that, in the presence of H2, CH4 will primarily be used for synthesis of cell carbon and increased biomass/protein yield. In particular, we intended to explore those CH4/O2 ratios, which maximize the effect of hydrogen addition on the biomass yield and proteome reconstruction of strain SC2. To achieve our goals, we combined hydrogen-based growth experiments with our recently optimized proteomics workflow.