Transformation of Tetranuclear [{MoO3(Lcat)Cu}2]2- into Trinuclear [MoO2{Lcat}2Cu2] and Possible Implications on the Formation of Bis(MPT)Mo by MobA

Abstract

Many molybdoenzymes contain two molybdopterin (MPT) ligands but the mechanism for the transformation of mono(MPT)Mo to bis(MPT)Mo is lacking. Using a catecholate-based system, we demonstrate that [MoVI(Lcat)O3]2- forms a dimeric structure, which spontaneously disproportionates to produce [MoVI(Lcat)2O2]2- and molybdate. This suggests a similar transformation of [{MoO3(MPT)}2]4- into [MoO2(MPT)2]2- is feasible.