The enzyme catalyses the reaction in the direction of producing (5-formylfuran-3-yl)methyl phosphate, an intermediate in the biosynthesis of methanofuran. The sequence of events starts with the removal of a phosphate group, followed by aldol condensation and cyclization. Methanofuran is a carbon-carrier cofactor involved in the first step of the methanogenic reduction of carbon dioxide by methanogenic archaea. Formerly EC?4.1.99.21.
