Isolation and purification of an aminoacylase fromAspergillus oryzae

An aminoacylase (EC 3.5.1.14) has been isolated from a surface culture of the fungusAspergillus oryzae (amilorizin P10X) with a 764-fold degree of purification, an activity yield of 32.7%, and a specific activity in relation to the hydrolysis of N-acetyl-D,L-methionine of 99.3 a.u./o.u. The scheme of the purification of the aminoacylase fromAspergillus oryzae includes: extraction at pH 6.7, precipitation with ammonium sulfate (30 and 80% saturation), gel filtration on Acrilex P-150 (pH 7.5), ion-exchange chromatography on amino-Silochrom Cx-1,5 (mean pore radius 790 Å); the sorption of the enzyme takes place at pH 6.2 and elution with 0.05 M borate buffer, pH 8.0; ion-exchange chromatography on AH-Sepharose 4B at pH 8.0, with elution by a stepwise increase in the concentration of sodium chloride to 0.25 M; and, finally, gel filtration on Sephadex G-200 (pH 8.0). According to the results of disk electrophoresis in 7.5% polyacrylamide gel in a Tris-glycine systems of buffers with a separation pH of 8.9 in the presence of Co²⁺ ions (10^–5 M) of theAspergillus oryzae aminoacylase, two components possessing enzymatic activity were detected, with R_f 0.53 (major component) and R_f 0.63 (minor component).All-Union Scientific-Research Institute for the Genetics and Breeding of Industrial Microorganisms, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 619–624, September–October, 1983.