aminolevulinic acid (ALA) /am′inōlev′o̅o̅lin″ik/ , the aliphatic precursor of heme. It is formed in the body from the condensation of glycine and succinyl coenzyme A and undergoes further condensation to form porphobilinogen. Aminolevulinic acid may be detected in the urine of some patients with porphyria, liver disease, and lead poisoning.
