FIG. 3.

Hydrolysis of fumarodinitrile and decanoic acid dinitrile by the purified nitrilase from Synechocystis sp. strain PCC6803. The reactions were performed in 1 ml of Na-K phosphate buffer (pH 7.0) containing 1 mM (♦) or 3 mM (•) fumarodinitrile (left panel) or decanoic acid dinitrile (right panel) and 80 μg of purified enzyme. Aliquots (100 μl each) were removed after different time intervals, the reactions were terminated by the addition of 10 μl of HCl (1 M), and precipitated protein was removed by centrifugation (2 min, 16,600 × g). The concentration of ammonia was subsequently determined by using the Spectroquant test.