[Glucose isomerase activity in suspension of Arthrobacter nicotianae cells and adsorption immobilization of the microorganisms on inorganic carriers].

Kinetics of monosaccharide isomerization has been studied in suspensions of intact, non-growing Arthrobacter nicotianae cells. Under the conditions of the study, glucose and fructose were isomerized at the same maximum rate of 700 micromol/min per 1 g dried cells, which increased with temperature (the dependence was linear at 60-80 degrees C). The proposed means of adsorption immobilization of A. nicotianae cells involve inorganic carriers differing in macrostructure, chemical nature, and surface characteristics. Biocatalysts obtained by adsorbing the cells of A. nicotianae on carbon-containing foam ceramics in the coarse of submerged cultivation were relatively stable and retained original activity (catalysis of monosaccharide isomerization) throughout 14 h of use at 70 degrees C. Maximum glucose isomerase activity (2 micromol/min per 1 g) was observed with biocatalysts prepared by adsorption of non-growing A. nicotianae cells to the macroporous carbon-mineral carrier Sapropel and subsequent drying of the cell suspension together with the carrier.