2-Aminoisobutyric Acid (AIB)

2-Aminoisobutyric acid is an amino acid with the structural formula is H2N-C(CH3)2-COOH. It is contained in some antibiotics of fungal origin, e.g. alamethicin and some lantibiotics. It is not one of the proteinogenic amino acids and rather rare in nature (cf. Non-proteinogenic amino acids). α-Aminoisobutyric acid is a strong helix inducer in peptides. Its oligomers form 3-10 helices. In the laboratory, 2-aminoisobutyric acid may be prepared from acetone cyanohydrin, by reaction with ammonia followed by hydrolysis. The biological tissue distribution of carbon 14-labeled alpha-aminoisobutyric acid (AIB), a synthetic, nonmetabolized amino acid, was determined in nude mice bearing human malignant melanoma heterotransplants in order to investigate the feasibility of using carbon 11 (t 1/2, 20.4 min)-labeled AIB for the visualization of human melanoma in vivo with positron emission tomography (PET).