Characterization of an Aminopeptidase A from Tetragenococcus halophilus CY54 Isolated from Myeolchi-Jeotgal.

In this study, a gene encoding glutamyl (aspartyl)-specific aminopeptidase (PepA; E.C. 3.4.11.7) was cloned from CY54. The translated PepA from CY54 showed very low similarities with PepAs from and genera. The from CY54 was overexpressed in BL21(DE3) using pET26b(+). The recombinant PepA was purified by using an Ni- NTA column. The size of the recombinant PepA was 39.13 kDa as determined by SDS-PAGE, while its optimum pH and temperature were pH 5.0 and 60°C, respectively. In addition, the PepA was completely inactivated by 1 mM EDTA, indicating its metallopeptidase nature. The m and max of the PepA were 0.98 ± 0.006 mM and 0.1 ± 0.002 mM/min, respectively, when Glu-NA was used as the substrate. This is the first report on PepA from species.