Quantitative assessment of methane bioconversion based on kinetics and bioenergetics

The biological conversion of methane under ambient conditions can be performed by methanotrophs that utilize methane as both a sole source of energy and a carbon source. However, compared to the established microbial chassis used for general fermentation with sugar as a feedstock, the productivity of methanotrophs is low. The fundamental knowledge of their metabolic or cellular bottlenecks is limited. In this review, the industrial-scale potential of methane bioconversion was evaluated. In particular, the enzyme kinetics associated with the oxidation and assimilation of methane were investigated to evaluate the potential of methane fermentation. The kinetics of enzymes involved in methane metabolism were compared with those used in the metabolic processes of traditional fermentation (glycolysis). Through this analysis, the current limitations of methane metabolism were identified. Methods for increasing the efficiency of methane bioconversion and directions for the industrial application of methane-based fermentation were discussed.