5,6,7,8-tetrahydromethanopterin + A = 7,8-dihydromethanopterin + AH2
5,6,7,8-tetrahydromethanopterin + a = 7,8-dihydromethanopterin + ah2
5,6,7,8-tetrahydromethanopterin + A = 7,8-dihydromethanopterin + AH2
5,6,7,8-tetrahydromethanopterin + a = 7,8-dihydromethanopterin + ah2