Characterization of an L-Arabinose Isomerase from Bacillus thermoglucosidasius for D-Tagatose Production

摘要

L-Arabinose isomerase from Bacillus thermoglucosidasius KCTC 1828 (BTAI) was expressed in Escherichia coli. The optimal temperature and pH for the activity of the purified BTAI were 40 °C and pH 7.0. The Mn~(2+) ion was an activator of BTAI activity. The kinetic parameters of BTAI for D-galactose were a K_m of 175 mm and a k_(cat)/K_m of 2.8 mM~(-1)min~(-1). The conversion ratio by BTAI to D-tagatose reached 45.6% at 40 °C.