Description
The enzymes isolated from the bacteria Pseudomonas cichorii, Pseudomonas sp. ST-24, Rhodobacter sphaeroides and Mesorhizobium loti catalyse the epimerization of various ketoses at the C-3 position, interconverting D-fructose and D-psicose, D-tagatose and D-sorbose, D-ribulose and D-xylulose, and L-ribulose and L-xylulose. The specificity depends on the species. The enzymes from Pseudomonas cichorii and Rhodobacter sphaeroides require Mn2+