Structure and Substrate Specificity of -Methyl Thiourocanate Hydratase.

Nicotinamide adenine dinucleotide (NAD) is a common cofactor in enzyme-catalyzed reactions that involve hydride transfers. In contrast, urocanase and urocanase-like enzymes use NAD for covalent electrophilic catalysis. Deciphering avenues by which this unusual catalytic strategy has diversified by evolution may point to approaches for the design of novel enzymes.