beta -galactosidase from Thermus sp

摘要

A beta -galactosidase having a high thermostability is produced by Thermus sp. FERM BP-1678, FERM BP-1679, and FERM BP-1680. The beta -galactosidase has an optimum temperature of 75 to 85 degrees celsius, and an optimum pH of 4.5 to 6.5 and an enzymatic activity which is not lowered substantially by 50 mM each of galactose and glucose. The beta -galactosidase is used to hydrolyze lactose in foods, such as milk, at a high temperature at which the putrefaction by saprophytes is difficult.