5,10-methenyl-5,6,7,8-tetrahydromethanopterin + NADPH => 5,10-methylenetetrahydromethanopterin + NADP(+)
5,10-methenyl-5,6,7,8-tetrahydromethanopterin + nadph => 5,10-methylenetetrahydromethanopterin + nadp(+)