A novel coenzyme from bacterial primary alcohol dehydrogenases

METHYLOTROPHIC bacteria are able to use methane derivatives as their sole source of carbon and metabolic energy and so can sustain growth on methane, methanol and other organic compounds which lack carbon–carbon bonds1. They are not autotrophic and, being unable to use carbon dioxide, rely ultimately on their ability to oxidise these substances. Although the primary alcohol dehydrogenases from a variety of methanol-grown bacteria have been purified and compared, and despite the increasing commerical importance of these organisms as sources of ‘single cell protein’, the essential features of these oxidative pathways remain unknown. The dehydrogenases exhibit a rather broad substrate specificity for primary alcohols and formaldehyde, and seem to contain a common and novel cofactor2–6, which may be more generally associated with the oxidation of single-carbon compounds. The structure of the cofactor is reported here.