[Beta-galactosidase of the superthermophilic anaerobic bacteria Thermoanaerobium sp. 2905 and its immobilization].

The composition of nutrition medium for cultivating the extreme thermophilic anaerobe Thermoanaerobium sp. 2905 was optimized, which enabled the bacterial beta-galactosidase production to be substantially enhanced. Xylan and ammonium phosphate were selected as optimal carbon and nitrogen sources, respectively. The enzyme was purified fivefold by precipitation of the aqueous cell extract with alcohol (1:1, v/v), and crude preparation with a specific activity of 46 U per mg protein was obtained. Cells of the extreme thermophile were entrapped into natural or synthetic latex.