sucrose catabolic process

Definition

Target type: biologicalprocess

The chemical reactions and pathways resulting in the breakdown of sucrose, the disaccharide fructofuranosyl-glucopyranoside. [GOC:go_curators]

Sucrose catabolism is the breakdown of sucrose, a disaccharide composed of glucose and fructose, into its constituent monosaccharides. This process is essential for energy production and the utilization of sugars in living organisms. It occurs primarily in the cytoplasm of plant and animal cells and involves a series of enzymatic reactions.

1. **Hydrolysis by Sucrase:** Sucrose catabolism begins with the hydrolysis of sucrose by the enzyme sucrase. Sucrase cleaves the glycosidic bond between glucose and fructose, resulting in the formation of free glucose and fructose.

2. **Glucose Metabolism:** The liberated glucose can then enter glycolysis, the central pathway of carbohydrate metabolism. Glycolysis is a ten-step process that converts glucose into pyruvate, generating ATP (adenosine triphosphate) and reducing equivalents (NADH).

3. **Fructose Metabolism:** Fructose, on the other hand, follows a different metabolic pathway. It is first phosphorylated by fructokinase to form fructose-1-phosphate. Subsequently, fructose-1-phosphate is cleaved by aldolase B into glyceraldehyde-3-phosphate and dihydroxyacetone phosphate, both of which are intermediates in glycolysis.

4. **Energy Production:** The breakdown of glucose and fructose through glycolysis generates ATP, the primary energy currency of cells. The reducing equivalents generated during glycolysis are used in oxidative phosphorylation, a process that further generates ATP from the oxidation of NADH and FADH2.

5. **Regulation:** Sucrose catabolism is tightly regulated to ensure the appropriate supply of energy and building blocks for cells. The activity of sucrase and other enzymes involved in the process is regulated by factors such as substrate availability, hormone levels, and cellular energy status.

6. **Biological Significance:** Sucrose catabolism is a crucial process for all living organisms. It provides energy for cellular processes, supplies precursor molecules for biosynthesis, and plays a role in regulating blood sugar levels. In plants, sucrose catabolism is essential for the transport and utilization of sugars produced during photosynthesis. In animals, it is involved in the digestion and metabolism of dietary sugars.'
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Proteins (1)

Compounds (30)