methane to CH3OH using methane monooxygenases (MMOs). Furthermore, two types of MMO have been isolated from methanotrophs: soluble methane monooxygenase (sMMO) and particulate methane monooxygenase (pMMO). Cells containing pMMO have demonstrated higher growth capabilities and higher affinity for methane than sMMO containing cells. It is suspected that copper ions may play a key role in both pMMO regulation and the enzyme catalysis, thus limiting pMMO cells to more copper-rich environments than sMMO producing cells. See also Borg (microbiology) References External links Anaerobic oxidation of methane Methane-Eating Bug Holds Promise For Cutting Greenhouse Gas. Media Release, GNS Science, New Zealand Pseudomonadota