MoeA family. Members of this family are involved in biosynthesis of the molybdenum cofactor (MoCF), an essential cofactor of a diverse group of redox enzymes. MoCF biosynthesis is an evolutionarily conserved pathway present in eubacteria, archaea and eukaryotes. MoCF contains a tricyclic pyranopterin, termed molybdopterin (MPT). MoeA, together with MoaB, is responsible for the metal incorporation into MPT, the third step in MoCF biosynthesis. The plant homolog Cnx1 is a MoeA-MogA fusion protein. The mammalian homolog gephyrin is a MogA-MoeA fusion protein, that plays a critical role in postsynaptic anchoring of inhibitory glycine receptors and major GABAa receptor subtypes.