Glykolat

Glykolat, also known as glycolate, refers to the deprotonated form of glycolic acid or to salts and esters derived from glycolic acid. The glycolate anion has the formula C2H3O3−, while the parent acid glycolic acid is C2H4O3. It is a small hydroxycarboxylate that occurs in various natural and synthetic forms, depending on pH and context.

Biological role and occurrence: In plants, glycolate is a central intermediate in photorespiration. It is produced when the enzyme RuBisCO oxygenates ribulose-1,5-bisphosphate, forming 2-phosphoglycolate which is dephosphorylated to glycolate. Glycolate is transported to peroxisomes and oxidized to glyoxylate, generating hydrogen peroxide. Glyoxylate is then transaminated to form glycine and, through subsequent reactions, the carbon skeleton is returned to the Calvin cycle as 3-phosphoglycerate. In animals, plants, and microorganisms, glycolate appears as a minor metabolite from various oxidative pathways and can be further metabolized or excreted.

Industrial and research context: Glycolate and its salts or esters are used in cosmetics, as chelating agents, and as intermediates in organic synthesis. In biochemical research, glycolate serves as a substrate and probe for studying peroxisomal and mitochondrial metabolism and for investigating pathways related to photorespiration.

Safety and handling: Glycolate salts are generally of low acute toxicity, but concentrated solutions can be irritating. Standard chemical hygiene practices apply when handling these compounds.

See also: Glyoxylate, photorespiration, glycolic acid.

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