entkaurenoic

Ent-kaurenoic acid is a natural diterpenoid carboxylic acid with the ent-kaurane skeleton. It is a key intermediate in the early steps of gibberellin biosynthesis in many plants. The biosynthetic pathway for gibberellins begins with geranylgeranyl diphosphate, which is converted through several steps to ent-kaurene. Oxidation of ent-kaurene by ent-kaurene oxidase yields ent-kaurenoic acid, which is then acted upon by ent-kaurenoic acid oxidase to form GA12, a central gibberellin precursor. From GA12, additional enzymatic steps produce the various gibberellins that regulate plant growth and development.

Occurrence and significance: Ent-kaurenoic acid has been detected in a wide range of plant species, including cereals, legumes, and woody plants, as part of the gibberellin biosynthetic pool. It is typically present in small amounts within plant tissues and can be produced in experimental systems for research purposes.

Chemical and physical properties: As a lipophilic diterpenoid containing a carboxylic acid group, ent-kaurenoic acid has limited water solubility. It is usually isolated from plant extracts as a solid or oil, depending on preparation and purity. Its reactivity is largely governed by the carboxyl group and the hydrocarbon skeleton.

Research and applications: Ent-kaurenoic acid is used in biochemistry and plant physiology to study the gibberellin biosynthetic pathway and its regulation. It is also utilized in metabolic engineering contexts to explore modulation of gibberellin production in plants or microbial systems.

See also: gibberellins, ent-kaurene, KAO (ent-kaurenoic acid oxidase).