ISOLATION AND CHARACTERIZATION OF A NITRILE HYDRATASE FROM A RHODOCOCCUS SP

A new nitrile hydratase producing strain of Rhodococcus has been found. A method for purification of the nitrile hydratase and a characterization of the enzyme is described. The hydratase is a 52‐kdal protein consisting of two subunits of molecular weights, 26 and 23 kdal, respectively. The hydratase exhibits a broad substrate specificity. Aliphatic saturated or unsaturated nitriles, as well as aromatic nitriles, are substrates for the enzyme. Inhibition of the enzyme activity by amides and carboxylic acids was observed. The optimum pH of the hydratase is 7.5. The enzyme is rather unstable, even at room temperature. The enzyme may be applied for the production of acrylamide. For this application of the enzyme, the optimal temperature is about 4°C, where the enzyme exhibits a satisfactory activity and stability. Copyright © 1990 Society of Chemical Industry