Catalytic mechanisms of CHLαGcT. The kinetic data are consistent with an ordered Bi-Bi reaction mechanism. UDP-Glc binds to CHLαGcT (E) prior to cholesterol binding, and α-glucosyl cholesterol (Glc-CHL) is released prior to UDP release from the enzyme-UDP complex. The arrows indicate the directions of reactions. kp represents a kinetic constant to form a product, Glc-CHL. Adapted from Lee, H.; Wang, P.; Hoshino, H.; Ito, Y.; Kobayashi, M.; Nakayama, J.; Seeberger, P.H.; Fukuda, M. Glycobiology, 2008, 18(7), 549–558.