Si-face stereospecificity at C5 of coenzyme F420 for F420-dependent N5,N10-methylenetetrahydromethanopterin dehydrogenase, F420-dependent N5,N10-methylenetetrahydromethanopterin reductase and F420H2:dimethylnaphthoquinone oxidoreductase.
Coenzyme F420-dependent enzymes catalyze the reversible reduction of F420 by stereospecific hydride transfer to C5 of 5-deazaflavin. Two F420-dependent enzymes have been investigated with respect to the stereochemistry of hydride transfer, the F420-dependent NADP reductase and the F420-reducing hydrogenase. Both enzymes were found to be Si-face specific. In this study we report that three additional F420-dependent enzymes are also Si-face specific: N5,N10-methylenetetrahydromethanopterin dehydrogenase, N5,N10-methylenetetrahydromethanopterin reductase and coenzyme F420H2: dimethylnaphthoquinone oxidoreductase (F420H2 dehydrogenase). Thus, all five characterized F420-dependent enzymes are Si-face specific, which is noteworthy since coenzyme F420 is functionally similar to pyridine nucleotides and both Si-face specific and Re-face specific pyridine-nucleotide-dependent enzymes exist.
Kunow
J
J
Laboratorium für Mikrobiologie des Fachbereichs Biologie, Philipps-Universität Marburg, Germany.
Schwörer
B
B
Setzke
E
E
Thauer
R K
RK
D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000378:metabolism*; D000587:Oxidoreductases Acting on CH-NH Group Donors / Q000378:metabolism*; D012256:Riboflavin / Q000031:analogs & derivatives* / Q000378:metabolism; D013237:Stereoisomerism
C015084:coenzyme F420; C072742:F420H2 dehydrogenase; D010088:Oxidoreductases; D000587:Oxidoreductases Acting on CH-NH Group Donors; C047126:methylenetetrahydromethanopterin dehydrogenase; D012256:Riboflavin