Now, the enzyme that catalyze this step is known as phosphorglucomutase. And what this enzyme does is the following. Inside the active side of this enzyme is a phosphorylated serine residue. And that phosphoryl group on that serene residue is initially placed onto carbon one. And what that generates is an intermediate molecule known as glucose one six bisphosphate. In the second step that is not shown here, this blue phosphoryl group is transferred back onto that Serene residue and that regenerates the catalytic enzyme, the phosphoglucomutase.