Enzymes of glucose isomerization in various microorganisms

Screening tests for glucose-isomerizing strains of various type, reference and laboratory strains of bacteria including actinomycetes, and yeasts were carried out. The ability to convert glucose to fructose was found to be widely distributed among various microorganisms. It was shown that glucose-isomerizing ability was most prevalent in the genera Aerobacter and Escherichia, but was not found in the bacterial genera belonging to the order Pseudomonadales. Although their activities were not very high (probably due to unsuitable culture conditions) more than 70% of the actinomycetes and 60% of the yeasts grown on xylose possessed glucose-isomerizing activity.