Methanofurans (MFRs) are a family ofchemical compounds found inmethanogenicarchaea.[1] These species feature a 2-aminomethylfuran linked tophenoxy group. At least three different end groups are recognized: R = tricarboxyheptanoyl (methanofuran),glutamyl-glutamyl (methanofuran b), tricarboxy-2-hydroxyheptanoyl (methanofuran c, see picture).
Methanofuran converts toformylmethanofuran in an early stage ofmethanogenesis. The enzyme formylmethanofuran dehydrogenase (EC: 1.2.99.5)formylates methanofuran usingCO
2, the primary C1 source in methanogenesis.[2]
Theenzyme formylmethanofuran:tetrahydromethanopterin formyltransferasecatalyzes the transfer of theformyl group from formylmethanofuran to N5 ontetrahydromethanopterin,H
4MPT. This enzyme has been crystallized; it contains noprosthetic group.[3]