Question

What is the first reaction of the pentose phosphate pathway?

(a) Oxidation of glucose 6-phosphate to 6-phosphoglucono-δ-lactone

(b) Oxidation of 6-phosphogluconate to ketopentose ribulose 5-phosphate

(c) Reduction of 6-phosphoglucono-δ-lactone to glucose 6-phosphate

(d) Reduction of ketopentose ribulose 5-phosphate to 6-phosphogluconate

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This question is from Pentose Phosphate Pathway of Glucose Oxidation in section Principles of Bioenergetics and Glycolysis of Biochemistry

Answer 1

The correct answer is (a) Oxidation of glucose 6-phosphate to 6-phosphoglucono-δ-lactone

For explanation: The first reaction of the pentose phosphate pathway is the oxidation of glucose 6-phosphate to 6-phosphoglucono-δ-lactone by glucose 6-phosphate dehydrogenase.