Methanofuran

Structure of the methanofurans

Methanofuran describes a family of chemical compounds found in methanogenic archaea.^[1] These species feature a 2-aminomethylfuran linked to phenoxy group. At least three different end groups are recognized: R = tricarboxyheptanoyl (methanofuran), glutamyl-glutamyl (methanofuran b), tricarboxy-2-hydroxyheptanoyl (methanofuran c, see picture).

Formylation of MFR

Methanofuran converts to formylmethanofuran in an early stage of methanogenesis. The enzyme formylmethanofuran dehydrogenase (EC: 1.2.99.5) formylates methanofuran using CO₂, the primary C1 source in methanogenesis.^[2]

Deformylation of MFR

The enzyme formylmethanofuran:tetrahydromethanopterin formyltransferase catalyzes the transfer of the formyl group from formylmethanofuran to N5 on tetrahydromethanopterin, ḥ. This enzyme has been crystallized; it contains no prosthetic group.^[3]

References

1. ^ Thauer RK (September 1998). "Biochemistry of methanogenesis: a tribute to Marjory Stephenson. 1998 Marjory Stephenson Prize Lecture". Microbiology 144 (Pt 9): 2377–406. PMID 9782487. http://mic.sgmjournals.org/cgi/pmidlookup?view=long&pmid=9782487. 
2. ^ Vorholt JA, Thauer RK (September 1997). "The active species of CO₂ utilized by formylmethanofuran dehydrogenase from methanogenic Archaea". Eur. J. Biochem. 248 (3): 919–24. PMID 9342247. http://onlinelibrary.wiley.com/resolve/openurl?genre=article&sid=nlm:pubmed&issn=0014-2956&date=1997&volume=248&issue=3&spage=919. 
3. ^ Acharya P, Warkentin E, Ermler U, Thauer RK, Shima S (March 2006). "The structure of formylmethanofuran: tetrahydromethanopterin formyltransferase in complex with its coenzymes". J. Mol. Biol. 357 (3): 870–9. doi:10.1016/j.jmb.2006.01.015. PMID 16466742. http://linkinghub.elsevier.com/retrieve/pii/S0022-2836(06)00043-X.