Title MINIREVIEW] Hydroxylation of methane through component interactions in soluble methane monooxygenases
Author Seung Jae Lee
Address Department of Chemistry and Research Institute of Physics and Chemistry, Chonbuk National University, Jeonju 54896, Republic of Korea
Bibliography Journal of Microbiology, 54(4),277-282, 2016,
DOI 10.1007/s12275-016-5642-6
Key Words methane monooxygenase, oxydoreductase, diiron active site, reductase, hydroxylation, methane
Abstract Methane hydroxylation through methane monooxygenases (MMOs) is a key aspect due to their control of the carbon cycle in the ecology system and recent applications of methane gas in the field of bioenergy and bioremediation. Methanotropic bacteria perform a specific microbial conversion from methane, one of the most stable carbon compounds, to methanol through elaborate mechanisms. MMOs express particulate methane monooxygenase (pMMO) in most strains and soluble methane monooxygenase (sMMO) under copper-limited conditions. The mechanisms of MMO have been widely studied from sMMO belonging to the bacterial multicomponent monooxygenase (BMM) superfamily. This enzyme has diiron active sites where different types of hydrocarbons are oxidized through orchestrated hydroxylase, regulatory and reductase components for precise control of hydrocarbons, oxygen, protons, and electrons. Recent advances in biophysical studies, including structural and enzymatic achievements for sMMO, have explained component interactions, substrate pathways, and intermediates of sMMO. In this account, oxidation of methane in sMMO is discussed with recent progress that is critical for understanding the microbial applications of C-H activation in one-carbon substrates.