A crystalline amino dicarboxylic acid HOOCCH2CH2CH(NH2)COOH that exists in three optically ismeric forms and occurs usu. as the dextrorotatory L-form both free and combined in glutamine and many proteins in plants and animals, that is usu. obtained by hydrolysis of gluten or from the waste waters of beet-sugar manufacture or by fermentation, and that takes part in transaminations and related metabolic reactions in the living organism; a-amino-glutaric acid
ref: Webster's International Unabridged Dictionary