Which of the following is the rate-limiting enzyme of gluconeogenesis?

Phosphofructokinase-1 is the rate-limiting enzyme of glycolysis - option a is excluded Pyruvate kinase catalyses one of the irreversible reactions of glycolysis and the reactions is a substrate-level phosphorylation(SLP) - option b is excluded Glycerol kinase is involved in gluconeogenesis, triglyceride, phospholipid synthesis. It is not a rate-limiting enzyme of gluconeogenesis - option c is excluded. Fructose 1,6-bisphosphatase conves fructose 1,6-bisphosphate to fructose 6-phosphate, using one water molecule and releasing one phosphate. This is one of the four rate-limiting steps of gluconeogenesis - option d is the answer.