Re-face stereospecificity of NADP dependent methylenetetrahydromethanopterin dehydrogenase from Methylobacterium extorquens AM1 as determined by NMR spectroscopy.
MtdA catalyzes the dehydrogenation of N(5),N(10)-methylenetetrahydromethanopterin (methylene-H4MPT) with NADP(+) as electron acceptor. In the reaction two prochiral centers are involved, C14a of methylene-H4MPT and C4 of NADP(+), between which a hydride is transferred. The two diastereotopic protons at C14a of methylene-H4MPT and at C4 of NADPH can be seen separately in 1H-NMR spectra. This fact was used to determine the stereospecificity of the enzyme. With (14aR)-[14a-2H(1)]-[14a-13C]methylene-H4MPT as the substrate, it was found that the pro-R hydrogen of methylene-H4MPT is transferred by MtdA into the pro-R position of NADPH.
Hagemeier
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Max-Planck-Institut für terrestrische Mikrobiologie and Laboratorium für Mikrobiologie des Facherbereichs Biologie der Philipps-Universität, Marburg, Germany.
Bartoschek
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Griesinger
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Thauer
R K
RK
Vorholt
J A
JA
D020601:Methylobacterium extorquens / Q000201:enzymology*; D015394:Molecular Structure; D009249:NADP / Q000737:chemistry*; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods; D000587:Oxidoreductases Acting on CH-NH Group Donors / Q000737:chemistry*; D011622:Pterins / Q000737:chemistry
C091917:N(5),N(10)-methylene-tetrahydromethanopterin; D011622:Pterins; D009249:NADP; D000587:Oxidoreductases Acting on CH-NH Group Donors; C047126:methylenetetrahydromethanopterin dehydrogenase