Characterization of a Thermally Stable β-galactosidase Produced by Thermophilic Anoxybacillus sp. AH1

Thermostable β-galactosidases from thermophilic bacteria have attracted increasing interest to various advantages in industrial and biotechnological applications. In this study, a highly thermally stable β-galactosidase produced by Anoxybacillus sp. AH1was purified characterized. The highest enzyme production was achieved after the bacterium incubated for 24 hours. precipitation with ammonium sulphate dialysis, gel filtration chromatography using Sephadex G-75. After purification steps, found be 10.2-fold yield of 13.9%. molecular mass galactosidase estimated 75 kDa SDS-PAGE. retained at 71% original activity 60 °C 53% 70 oC within 120 minutes. Km Vmax values were calculated as 1.249 mM 0.5 μmol minutes-1, respectively. Ca2+, Zn2+, Mg2+ significantly activated activity, whereas inhibited Cu+2 well metal ion chelators1,10-phenanthroline (phen) ethylenediaminetetraacetic acid (EDTA). Purified increased PMSF (phenylmethylsulfonyl fluoride), PCMB (p-chloromercuribenzoic acid), DTT (dithiothreitol), β-ME (β-mercaptoethanol) 2 mM, but completely NEM (N-ethylmaleimide) 1 mM.