Molybdenum Cofactor-Containing Enzymes and Pathways

To date, more than 50 enzymes are known to contain Mo and most of them occur in prokaryotes while only six were found in eukaryotes. In all organisms studied so far, the Mo-cofactor is synthesized by a highly conserved biosynthetic pathway that can be divided into four steps, each producing a specific biochemical intermediate. Different nomenclatures were introduced for genes and gene products involved in Mo-co formation according to the organism they belong. On the basis of the active site structure and catalytic function, molybdenum- dependent enzymes can be grouped into two categories: bacterial nitrogenases and pterin-based enzymes. Human and plants Mo-co deficiency are also described.