Abstract
Physicochemical properties of the purified leucine amino peptidase from Aspergillus japonica were studied. The molecular weight of this enzyme was estimated to be approx. 31100 by sedimentation equilibrium, and the sedimentation coefficient (S20, W) was determined to be 3.12 S. The extinction coefficient at 278.5 nm, E1%1cm was 7.72 and the isoelectric point was at around pH 8.0 by gel electrofocusing. The helical content was calculated to be 1.7% from the Moffit-Yang plots. The amino acid analyses indicated that the enzyme was composed of 289 amino acid residues and contained one cystine. The amino-terminal amino acid was lysine, and the partial specific volume calculated from amino acid composition was 0.726.
