Purification and properties of a novel glycine amino peptidase from Actinomucor elegans and its potential application

Abstract

X . M A , X . Z H O U A N D T . Y O S H I M O T O . 2004.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 56AE5 kDa by SDS-PAGE. It hydrolysed glycine from substrate more efficiently than other amino acids. The optimal temperature for this enzyme was 40°C and at pH 8AE0 it showed its highest activity. The K m and K cat of the enzyme for glycine-b-naphthylamine was 0AE24 mM M and 100AE8 s )1 , respectively. Zinc, copper, cadmium and o-phenanthrolin suppressed almost all enzyme activities at the concentration of 1AE0 mM M. 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.

Phylogenetic Status of Two Undescribed Zygomycete Species from Korea:Actinomucor elegansandMucor minutus

“…Some of them are commonly used for producing popular fermented soybean foods including Sufu and Chao [ 8 ]. In addition, A. elegans is also considered a good source of glycine aminopeptidase and glucosamine [ 9 10 ]. A. elegans var.…”

Examining activity–pH relationships of soil nitrogen hydrolytic enzymes

“…Similar to protease pH optima, this indicates a mismatch between the environmental pH of the extracellular enzyme and the enzyme pH optima that may be attributable to pH‐dependent mechanism of catalysis, which likely evolved first for intracellular functions. For example, pH optima have been reported for purified LAP (pH 8.0–9.0) (Nampoothiri et al., 2005; Sopanen & Mikola, 1975), GAP (pH 8.0–8.4) (Ito et al., 2003; Ma et al., 2004; Murao et al., 1985), and AAP (pH 7.5–8.5) (Biagioni et al., 1990; Sidorowicz et al., 1981) of fungal, plant, and animal species. It should be noted that aminopeptidase activity pH optima have been found to be substrate‐sensitive by up to 1 pH unit (Biagioni et al., 1990), meaning that the apparent pH optima could differ from our chromogenic substrate ( p NA‐based) assays if assayed using fluorogenic or natural (e.g., dipeptide) substrates.…”

Debittering effect of Actinomucor elegans peptidases on soybean protein hydrolysates

“…Although leucine, proline, tyrosine, and valine were slightly bitter or tasteless at the tasted concentration, peptides coupled with glycine in their amino and carboxyl groups could become very bitter. Besides, Ma et al [18] found that the glycine amino peptidase was able to improve the protease activity considerably in the process of protein hydrolyzing. Table 3 shows that the carboxypeptidase activity towards N-CBZ-Ile-Leu is signiWcantly high in the A. elegans extract (p<0.01).…”