MUTANT GLUCOSE ISOMERASE SHOWING THE CHANGED SUBSTRATE SPECIFICITY AND A METHOD OF ITS PREPARING Russian patent published in 1997 - IPC

FIELD: biotechnology, food industry. SUBSTANCE: method involves the use of crystallography for analysis of glucose isomerase complexes with substrate or its analog-inhibitor. Method ensures to detect amino acid residues change of that in protein molecule provides the alternation of substrate specificity of enzyme. Then mutations in gene sequence encoding glucose isomerase, in part, obtaining from Actinoplanes missouriensis were obtained by site-directed mutagenesis procedure. These mutations provide the required amino acid substitutions. The mutant gene is expressed in recombinant vector in bacterial cells and enzyme mutants were obtained. The expressed mutant forms of glucose isomerase show the alternated kinetic constants (V_max and K_m) with respect to the parent natural enzyme form. EFFECT: improved method of preparing. 3 cl, 4 dwg , 8 tbl