N-formylmethanofuran + 5,6,7,8-tetrahydromethanopterin + H(+) => N(5)-formyl-5,6,7,8-tetrahydromethanopterin + methanofuran
n-formylmethanofuran + 5,6,7,8-tetrahydromethanopterin + h(+) => n(5)-formyl-5,6,7,8-tetrahydromethanopterin + methanofuran