6-Phosphogluconic acid, also known as 6-phospho-D-gluconate or gluconic acid-6-phosphate, belongs to the class of organic compounds known as monosaccharide phosphates. These are monosaccharides comprising a phosphated group linked to the carbohydrate unit. 6-Phosphogluconic acid is an extremely weak basic (essentially neutral) compound (based on its pKa). 6-Phosphogluconic acid exists in all living species, ranging from bacteria to humans. Within humans, 6-phosphogluconic acid participates in a number of enzymatic reactions. In particular, 6-phosphogluconic acid can be biosynthesized from gluconolactone; which is mediated by the enzyme 6-phosphogluconolactonase. In addition, 6-phosphogluconic acid can be converted into D-ribulose 5-phosphate through the action of the enzyme 6-phosphogluconate dehydrogenase, decarboxylating. In humans, 6-phosphogluconic acid is involved in the metabolic disorder called the transaldolase deficiency pathway. Outside of the human body, 6-Phosphogluconic acid has been detected, but not quantified in, several different foods, such as cascade huckleberries, common chokecherries, half-highbush blueberries, american cranberries, and okra. This could make 6-phosphogluconic acid a potential biomarker for the consumption of these foods. A gluconic acid phosphate having the phosphate group at the 6-position.