Immobilization of a Recombinant Strain Producing Glucose Isomerase inside SiO2-Xerogel and Properties of Prepared Biocatalysts

An original method of immobilization of non-growing microorganism cells inside xerogel of silicium dioxide containing insoluble hydroxyl compounds of cobalt(II) has been developed. A recombinant strain producing glucose isomerase has been constructed on the basis of Escherichia coli with the use of a gene of Arthrobacter nicotianae. It was revealed that glucose isomerase activity and stability of biocatalysts prepared on the basis of the recombinant E. coli strain was 3-5 times greater compared with the biocatalysts prepared with the use of the donor strain A. nicotianae. Under conditions of continuous hydrolysis of 3 M fructose at 62 65 degrees C in a fixed bed reactor, time of half-inactivation of the biocatalysts prepared from the recombinant strain and A. nicotianae was similar to 60 and similar to 25 days, respectively.