pentose phosphate pathway
Definition: a secondary pathway for the oxidation of d-glucose (not occurring in skeletal muscle), generating reducing power (NADPH) in the cytoplasm and synthesizing pentoses and a few other sugars. It also provides a means of converting pentoses and certain other sugars into intermediates of the glycolytic pathway. It proceeds from d-glucose 6-phosphate to d-ribulose and d-ribose phosphates, thence (with d-xylulose 5-phosphate) to d-sedoheptulose 7-phosphate and d-glyceraldehyde 3-phosphate; carbon dioxide is released in the gluconate-ribulose step. In plants, it participates in the formation of d-glucose from carbon dioxide in the dark reactions of photosynthesis. This pathway is defective in certain inherited diseases, glucose-6-phosphate dehydrogenase deficiency.
Synonym(s): Dickens shunt, hexose monophosphate pathway, hexose monophosphate shunt, pentose monophosphate shunt, pentose phosphate cycle, phosphogluconate pathway, Warburg-Dickens-Horecker shunt, Warburg-Lipmann-Dickens-Horecker shunt