Regarding the Embden-Meyerhof Pathway

Dear Sir/Madam:

. Prior to synthesizing ATP, it was necessary to first make a substrate having high-energy phosphate. The enzyme Enolase in the glycolysis pathway similarly makes a high- energy phosphate in preparation for the ATP synthesis. Enolase catalyses the formation of phosphoenolpyruvate (PEP) from 2-phosphoglycerate (2-PG), which involve the removal of water molecule. The free energy change is quite small, about 1.8kJ/mol under cellular condition.

So, my question for Sir is, how the Enolase transform a substrate with a low free energy into PEP with a very high free energy of hydrolysis ?

Thank you!

From : Kent