The Soluble Aminopeptidase System from Saccobolus platensis. Characterization of a New Glutamate Aminopeptidase

Fernández, Murray, P., and Passeron, S. 1995. The soluble aminopeptidase system from Saccobolus platensis. Characterization of a new glutamate aminopeptidase. Experimental Mycology 19, 214-222. The aminopeptidase pattern from the fungus Saccobolus platensis was investigated by ion-exchange chromatography fractionation of the soluble proteins. The chromogenic p-nitroanilide derivatives of nine different amino acids were used as substrates. Apart from the previously characterized major alanine aminopeptidase (P. Fernádez Murray, A. Samela, and S. Passeron, 1992. Exp. Mycol. 16, 279-290), two new minor aminopeptidase activities were found: one mainly a proline aminopeptidase and a second highly specific for the hydrolysis of the chromogenic derivative of glutamate. This last activity was subjected to ammonium sulfate fractionation and successive phenyl-Sepharose, DEAE-Sephacel, and Sephacryl S-200 HR column chromatography. A highly purified enzyme fraction was obtained. This new glutamate aminopeptidase had a molecular weight of 22 kDa and an optimum pH range of 7.2-8.0 and was inhibited by o-phenanthroline and bestatin.