Structure and catalytic mechanism of particulate methane monooxygenase

Particulate methane monooxygenase is a membrane-bound enzyme that catalyzes the oxidation of methane to methanol in methanotrophs. pMMO is expressed when metal ion is available, and its active site is believed to contain copper. Whereas sMMO is well characterized, most aspects of pMMO biochemistry remain unknown and somewhat controversial. This review emphasizes the advances in the past ten years in studies related to pMMO and copper-dependent regulation in methanotrophs. The pMMO metal centers have been characterized spectroscopically, and the first pMMO crystal structure has been determined.