X Ma1, X Zhou, T Yoshimoto. 1. Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, China. maxiaohong@zju.edu.cn
Abstract
AIMS: To study the properties and show the potential application of a glycine aminopeptidase from Actinomucor elegans. METHODS AND RESULTS: The enzyme was estimated to have molecular mass of 320 kDa by gel filtration and the subunit size of 56.5 kDa by SDS-PAGE. It hydrolysed glycine from substrate more efficiently than other amino acids. The optimal temperature for this enzyme was 40 degrees C and at pH 8.0 it showed its highest activity. The Km and Kcat of the enzyme for glycine-beta-naphthylamine was 0.24 mm and 100.8 s(-1), respectively. Zinc, copper, cadmium and o-phenanthrolin suppressed almost all enzyme activities at the concentration of 1.0 mm. In the process of hydrolysing proteins, it could improve the protease activity considerably. CONCLUSIONS: It was a hexamer metalloenzyme which was specific for the substrates with glycinse residue at the N-terminal and some metal cations were needed to maintain its activity. SIGNIFICANCE AND IMPACT OF THE STUDY: This study demonstrates the properties of a novel aminopeptidase and shows its potential application in the process of the food industry.
AIMS: To study the properties and show the potential application of a glycine aminopeptidase from Actinomucor elegans. METHODS AND RESULTS: The enzyme was estimated to have molecular mass of 320 kDa by gel filtration and the subunit size of 56.5 kDa by SDS-PAGE. It hydrolysed glycine from substrate more efficiently than other amino acids. The optimal temperature for this enzyme was 40 degrees C and at pH 8.0 it showed its highest activity. The Km and Kcat of the enzyme for glycine-beta-naphthylamine was 0.24 mm and 100.8 s(-1), respectively. Zinc, copper, cadmium and o-phenanthrolin suppressed almost all enzyme activities at the concentration of 1.0 mm. In the process of hydrolysing proteins, it could improve the protease activity considerably. CONCLUSIONS: It was a hexamer metalloenzyme which was specific for the substrates with glycinse residue at the N-terminal and some metal cations were needed to maintain its activity. SIGNIFICANCE AND IMPACT OF THE STUDY: This study demonstrates the properties of a novel aminopeptidase and shows its potential application in the process of the food industry.