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KREBS CYCLE

The Krebs cycle is a series of biochemical changes that occur during the metabolism of nutrients, facilitating the storage of energy for further use. It is named after Hans Adolph Krebs (1900–1981), the biochemist who identified it. The alternative, and more descriptive, name is the tricarboxylic, or citric acid, cycle. The fundamental process involves oxidizing acetate molecules to carbon dioxide (CO₂) and water with transfer of the metabolic energy to "high energy" bonds for later use by the body. In the process, acetate is attached biochemically to a dicarboxylic acid to produce citric acids—the tricarboxylic acid from which the cycle derives its name. The citric acid then goes through a number of biochemical steps to oxidize the two carbons from acetate, and to regenerate the dicarboxylic acid to which the acetate was originally attached.

GEORGE A. BRAY

(SEE ALSO: Energy; Nutrition)