phosphogluconate pathway

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A biochemical flowchart shows the metabolic pathways for carbohydrate utilization, including glycolysis, the pentose phosphate pathway, and the tricarboxylic acid (TCA) cycle. The diagram traces the conversion of glucose, fructose, and glycerol through various intermediates, leading to energy production, carbon dioxide release, and biosynthesis of amino acids and porphyrins. Key steps and branches are labeled, with colored boxes highlighting biosynthetic outputs.

phosphogluconate pathway

chemical reaction

Also known as: pentose phosphate cycle, pentose shunt glycolytic pathway, phosphogluconate oxidative glycolytic pathway(Show More)

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A biochemical flowchart shows the metabolic pathways for carbohydrate utilization, including glycolysis, the pentose phosphate pathway, and the tricarboxylic acid (TCA) cycle. The diagram traces the conversion of glucose, fructose, and glycerol through various intermediates, leading to energy production, carbon dioxide release, and biosynthesis of amino acids and porphyrins. Key steps and branches are labeled, with colored boxes highlighting biosynthetic outputs. — pathways for the utilization of carbohydrates Pathways for the utilization of carbohydrates.

The phosphogluconate pathway, also known as the pentose phosphate cycle, is a metabolic route for glucose catabolism. It begins with the oxidation of glucose 6-phosphate, catalyzed by glucose 6-phosphate dehydrogenase, producing 6-phosphogluconate and reducing NADP+ to NADPH. A second oxidation step, catalyzed by 6-phosphogluconate dehydrogenase, further oxidizes 6-phosphogluconate, yielding ribulose 5-phosphate and carbon dioxide.1

While not a primary route for glucose oxidation in most cells, this pathway is crucial for generating reducing power in the cytoplasm via NADPH. This is particularly important in tissues involved in fatty acid and steroid biosynthesis, such as the liver and adrenal gland. Additionally, the pathway provides pentoses necessary for nucleic acid synthesis. In photosynthetic organisms, some reactions of this pathway are involved in sugar formation from carbon dioxide. In some microorganisms lacking complete glycolysis, an alternative route involves the conversion of 6-phosphogluconate to 2-keto-3-deoxy-6-phosphogluconate (KDPG), which then splits into pyruvate and glyceraldehyde-3-phosphate.1

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metabolism
The phosphogluconate pathway
Many cells possess, in addition to all or part of the glycolytic pathway that comprises reactions [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, and 11], other pathways of glucose catabolism that involve, as the first unique step, the oxidation of…
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Many cells possess, in addition to all or part of the glycolytic pathway that comprises reactions [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, and 11], other pathways of glucose catabolism that involve, as the first unique step, the oxidation of…
Read More

blood disease
Hemolytic anemias
…through a pathway called the pentose phosphate pathway. The anaerobic pathway, the main route of metabolism, provides energy in the form of adenosine triphosphate (ATP). Deficiencies of enzymes such as pyruvate kinase in this pathway shorten red cell survival times because energy-requiring activities within the red cell are curtailed. Deficiencies…
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…through a pathway called the pentose phosphate pathway. The anaerobic pathway, the main route of metabolism, provides energy in the form of adenosine triphosphate (ATP). Deficiencies of enzymes such as pyruvate kinase in this pathway shorten red cell survival times because energy-requiring activities within the red cell are curtailed. Deficiencies…
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photosynthesis
Elucidation of the carbon pathway
…reduction pathway called the reductive pentose phosphate (RPP) cycle, or the Calvin-Benson cycle. An additional pathway for carbon transport in certain plants was later discovered in other laboratories (see above Carbon fixation in C₄ plants). All the steps in these pathways can be carried out in the laboratory by isolated…
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…reduction pathway called the reductive pentose phosphate (RPP) cycle, or the Calvin-Benson cycle. An additional pathway for carbon transport in certain plants was later discovered in other laboratories (see above Carbon fixation in C₄ plants). All the steps in these pathways can be carried out in the laboratory by isolated…
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plant
Principal pathways and cycles
…then enter glycolysis or the pentose phosphate pathway. The reactions of both pathways take place in the cytoplasm of the cell.
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…then enter glycolysis or the pentose phosphate pathway. The reactions of both pathways take place in the cytoplasm of the cell.
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