Microtubule-associated protein involved in membrane protein-cytoskeleton interactions. It is thought to anchor the inhibitory glycine receptor (GLYR) to subsynaptic microtubules (Probable). Acts as a major instructive molecule at inhibitory synapses, where it also clusters GABA type A receptors (By similarity). Has also a catalytic activity and catalyzes two steps in the biosynthesis of the molybdenum cofactor. In the first step, molybdopterin is adenylated. Subsequently, molybdate is inserted into adenylated molybdopterin and AMP is released. ATP + H(+) + molybdopterin = adenylyl-molybdopterin + diphosphate adenylyl-molybdopterin + H(+) + molybdate = AMP + H2O + Mo-molybdopterin Cofactor biosynthesis; molybdopterin biosynthesis. Homotrimer, homodimer and homooligomer (By similarity). Interacts with glycine receptors (PubMed:10649567). In the N-terminal section; belongs to the MoaB/Mog family. In the C-terminal section; belongs to the MoeA family.