Nitrile Hydratase Structure and Mechanism

Fe-(lll) Nitrile Hydratases Nitrile hydratases function as Lewis acids, in contrast to the mode of action of most nonheme iron center enzymes, which catalyze redox type reactions. The nitrile hydratase activity found in Rhodococcus N-771 [54-56] was found to be photoregulated, with light reversing the in vivo inhibitory nitric oxide (NO) binding and thereby activating the nitrile hydratase [56]. 

Amidase enzymes (EC 3.5.1.4) belong to the hydrolase family of enzymes and catalyze the hydrolysis of monocarboxylic amides to their corresponding acid products. Conventional amidase classification is done according to substrate profile or is based on their amino acid sequence homology [58]. 

Amidases play a significant role in both prokaryotes and eukaryotes, functioning in the production of growth regulators such as auxin and biotin in plants [59], in nutrient metabolism, in the degradation of toxic cyanogenic compounds, and finally in posttranslational modification of amino adds and proteins. 

---