title: H2-forming N5,N10-methylenetetrahydromethanopterin dehydrogenase: mechanism of H2 formation analyzed using hydrogen isotopes.
abstract: H2-forming N5,N10-methylenetetrahydromethanopterin dehydrogenase catalyzes the reversible dehydrogenation of N5,N10-methylenetetrahydromethanopterin (CH2 = H4MPT) to N5,N10-methenyltetrahydromethanopterin (CH = H4MPT+) and H2. In D2O both HD and D2 are formed from CH2 = H4MPT and in H2O both HD and H2 from CD2 = H4MPT. Evidence is presented that HD is not an intermediate in the formation of D2 and H2, respectively.
authors.affiliation: Laboratorium für Mikrobiologie, Philipps-Universität Marburg, Germany.
authors.forename: A R
authors.initials: AR
authors.lastname: Klein
authors.forename: V M
authors.initials: VM
authors.lastname: Fernández
authors.forename: R K
authors.initials: RK
authors.lastname: Thauer
mesh_terms: D017666:Deuterium Oxide / Q000378:metabolism*; D006859:Hydrogen / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D017014:Methanobacterium / Q000201:enzymology; D000587:Oxidoreductases Acting on CH-NH Group Donors / Q000378:metabolism*
chemical_list: D006859:Hydrogen; D000587:Oxidoreductases Acting on CH-NH Group Donors; C047126:methylenetetrahydromethanopterin dehydrogenase; D017666:Deuterium Oxide