2-Aminoisobutyric acid
（重定向自Amino isobutyric acid）
2-Aminoisobutyric acid, or α-aminoisobutyric acid (AIB) or α-methylalanine or 2-methylalanine, 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. Oligomers of AIB form 310 helices.