Paleoclimate feeback involving co-oxidation of alpha-pinene by methane oxidizers

The methane mononxygenase (MMO) enzyme of methane oxidizing bacteria is relatively non-specific and is capable of co-oxidizing a variety of methylated compounds including alpha-pinene produced by conifers. Laboratory and field experiments indicate that aquatic and soil methane oxidation is inhibited by the presence of alpha-pinene as the MMO preferentially oxidizes pinene over methane. Since methane is a potent greenhouse gas, this suggests possible climatic controls between atmospheric methane levels and coverage of coniferous pine forests which may be reflected in stable isotope records.