L-arginine amidinohydrolase

The official EC name of this enzyme is L-arginine amidinohydrolase, the last word refers to the fact that the amidino group (dotted circle in the equation) is cleaved from arginine by introduction of a molecule of water across the C—N bond. In the reaction, a nonpeptide C—N bond is cleaved thus, the second EC number for arginase is 5 its whole classification number is 3.5.3.1. 

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