Glucose-6-phosphate isomerase is an enzyme that catalyzes the conversion of glucose-6-phosphate into fructose 6-phosphate in the second step of glycolysis. The human variant of this enzyme is encoded by the GPI gene.http://www.creative-enzymes.com/product/Native-Bacillus-Stearothermophilus-Phosphoglucose-Isomerase_758.html