Phosphorylation of ADP From 1,3-bisphosphoglycerate

In a reversible reaction, the phosphoryl group of the acid anhydride of glyceroyl phosphate is transferred to ADP by phosphoglycerate kinase. 

The net result of this reaction is the formation of two molecules of ATP per molecule of glucose. This formation of ATP is known as substrate-level phosphorylation to distinguish it from the oxidative phosphorylation coupled to electron transport that occurs in mitochondria (Chapter 14). In erythrocytes, 

---