Reaction 1: Phosphate Ester Synthesis
Phosphate is added to the glucose at the C-6 position. The
reaction is a phosphate ester synthesis using the alcohol on
the glucose and a phosphate from ATP.
This first reaction is endothermic and thus requires energy
from a coupled reaction with ATP. ATP is used by being
hydrolyzed to ADP and phosphate giving off energy and the phosphate
for reaction with the glucose for a net loss of ATP.
This reaction is catalyzed by hexokinase.