6PG

6PG refers to 6-phosphogluconate. It is a metabolic intermediate found in several biochemical pathways, most notably the pentose phosphate pathway and glycolysis. In the pentose phosphate pathway, 6-phosphogluconate is formed from glucose-6-phosphate and is then further metabolized to produce NADPH and ribulose-5-phosphate. This pathway is crucial for generating reducing power in the form of NADPH, which is essential for various reductive biosynthetic processes and for protecting cells against oxidative stress.

6-phosphogluconate also plays a role in the Entner-Doudoroff pathway, an alternative route for glucose breakdown found in some bacteria. In this pathway, 6-phosphogluconate is dehydrated and cleaved into pyruvate and glyceraldehyde-3-phosphate. The formation and subsequent reactions of 6-phosphogluconate are catalyzed by specific enzymes, including 6-phosphogluconate dehydrogenase in the pentose phosphate pathway and 6-phosphogluconate dehydratase in the Entner-Doudoroff pathway. The concentration of 6-phosphogluconate can be an indicator of the flux through these metabolic pathways.