description | Protein which binds molybdenum (or molybdopterin) or protein involved in the transport of molybdenum, a metallic element, chemical symbol Mo. It plays an essential role in the active site of all eukaryotic Mo-containing enzymes. In plants, Mo enzymes are important for nitrate assimilation, phytohormone synthesis, and purine catabolism. Mo is often coordinated to the sulfur atoms of a pterin derivative (molybdopterin [MPT]), thereby forming the active Molybdenum cofactor (Moco), which is highly conserved in eukaryotes, eubacteria, and archaebacteria |