A β-citryl-L-glutamate-hydrolysing enzyme in rat testes

An enzyme responsible for the deacylation of β-citryl-L-glutamate to citrate and glutamate has been characterized in rat testis. The enzyme required manganese ion for full activity and was strongly inhibited by nucleotides such as ATP or GTP. The activity was localized in the particulate fractions. The enzyme favored $\text{N-}\text{formyl-}\text{L}\text{-glutamate}\text{> β-}\text{citryl-}\text{L}\text{-glutamate}\text{> β-}\text{citryl-}\text{L}\text{-glutamine}$ in a decreasing order. The amidohydrolyase activity was highest in the testis and lung, a moderate activity was detected in heart, kidney and intestine, and low in brain, thymus, stomach, skeletal muscle, spleen and liver. These findings suggest that the amidohydrolase is different from any of amidohydrolases reported so far, amidohydrolase I (EC 3.5.1.14), II (EC 3.5.1.15), III, N-acetyl-lysine deacylase (EC 3.5.1.17) and N-acetyl-β-alanine deacetylase (EC 3.5.1.21), and various peptidases.