One mechanism for the catalysis of this reaction by urease was proposed by Blakely and Zerner. It begins with a nucleophilic attack by the carbonyl oxygen of the urea molecule onto the 5-coordinate Ni (Ni-1). A weakly coordinated water ligand is displaced in its place. A lone pair of electrons from one of the nitrogen atoms on the Urea molecule creates a double bond with the central carbon, and the resulting NH2− of the coordinated substrate interacts with a nearby positively charged group. Blakeley and Zerner proposed this nearby group to be a Carboxylate ion, although deprotonated carboxylates are negatively charged.
One mechanism for the catalysis of this reaction by urease was proposed by Blakely and Zerner. It begins with a nucleophilic attack by the carbonyl oxygen of the urea molecule onto the 5-coordinate Ni (Ni-1). A weakly coordinated water ligand is displaced in its place. A lone pair of electrons from one of the nitrogen atoms on the Urea molecule creates a double bond with the central carbon, and the resulting NH2− of the coordinated substrate interacts with a nearby positively charged group. Blakeley and Zerner proposed this nearby group to be a Carboxylate ion, although deprotonated carboxylates are negatively charged.