At the end of step 10 of Glycolysis (phosphoenolpyruvate to pyruvate) you generate 1 ATP. However from what I've been told there is actually enough energy to generate 2 ATP there but it doesn't happen for whatever reason.

 

So my question is what can you do to drive the reaction to produce that 2nd ATP? I heard something about using inorganic phosphate to drive the reaction but I don't know the details.

Only one ATP is produced because phosphoenolpyruvate has one phospho group which can be transfered producing ATP. In Glycolysis you got at that step 2 ATP because two phosphoenolpyruvate are converted to pyruvate and ATP.

 

I don't know if it it possible to drive the reaction to produce more ATP. Maybe in vitro but I doubt that is the way it works in cells. Especially because there is a negative regulation of pyruvate kinase by ATP.

I think the total free energy of the hydrolysis of PEP is roughly twice that of ATP. That allows the transfer of P from PEP to ADP. However, PEP has only one phosphate to offer. Where should the second come from?