[Thermostability of glutamine synthetase in Candida tropicalis feed yeasts in Mg-, Mn- and Co-activated systems].

The thermostability of glutamine synthetase of Candida tropicalis was studied in systems activated by Mg, Mn and Co. The enzyme was found to be very thermolabile. Its thermostability depended on the nature of a bivalent cation used in the reaction mixture. Metals stabilized the enzyme since preincubation with metal cations increased the thermostability of glutamine synthetase. Purification of the enzyme preparation increased the stabilizing action of bivalent cations (Mg2+, Mn2+, Co2+).