Question

Calculate what the net ATP yield (i.e., taking into consideration both consumption and production) of glycolysis would be in the complete absence of pyruvate kinase (PK)

A deficiency in the glycolytic enzyme PK, is one of the most common enzymatic defects of the red blood cell, with a frequency of about 51 cases per million individuals. This deficiency arises from a mutation in the PK gene that causes a less efficient (but still active) PK to be produced. There are no instances of an individual completely lacking PK in their red blood cells.

Answer 1

In general, glycolysis yields net 2 ATP molecules. Now, if the Pyruvate kinase(PK) enzyme is absent, the last step leading to the formation of pyruvate would not take place. So no ATP formation. This means that only a net yield of 1 ATP molecule will be there in glycolysis, if the PK enzyme is absent.