Open AccessThe Active Species of ‘CO 2 ’ Utilized by Formylmethanofuran Dehydrogenase from Methanogenic Archaea
Author(s) -
Vorholt Julia A.,
Thauer Rudolf K.
Publication year - 1997
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1997.00919.x
Subject(s) - archaea , methanogenesis , methanosarcina barkeri , enzyme , dehydrogenase , carbon monoxide dehydrogenase , methanosarcina , euryarchaeota , biochemistry , chemistry , active site , biology , methane , catalysis , ecology , gene , carbon monoxide
Formylmethanofuran dehydrogenase from methanogenic Archaea catalyzes the reversible conversion of CO 2 and methanofuran to formylmethanofuran, which is an intermediate in methanogenesis from CO 2 a biological process yielding approximately 0.3 billion tons of CH 4 per year. With the enzyme from Methanosarcina barkeri , it is shown that CO 2 rather than HCO 3 is the active species of ‘CO 2 ’ utilized by the dehydrogenase. Evidence is also presented that the enzyme catalyzes a methanofuran‐dependent exchange between CO 2 and the formyl group of formylmethanofuran. The results are consistent with N ‐carboxymethanofuran being an intermediate in CO 2 reduction to formylmethanofuran.