2-Aminoisobutyric acid
[CAS# 62-57-7]

Identification

• Classification: Biochemical >> Amino acids and their derivatives >> Alanine derivatives
• Name: 2-Aminoisobutyric acid
• Synonyms: 2-Amino-2-methylpropionic acid; alpha-Aminoisobutyric acid; 2-Methylalanine
• Molecular Formula: C₄H₉NO₂
• Molecular Weight: 103.12
• Protein Sequence: X
• CAS Registry Number: 62-57-7
• EC Number: 200-544-0
• SMILES: CC(C)(C(=O)O)N

Properties

• Melting point: 335 °C
• Water solubility: SOLUBLE

Safety Data

• Hazard Symbols: GHS07 Warning
• Risk Statements: H319
• Safety Statements: P264+P265-P280-P305+P351+P338-P337+P317

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Eye irritation	Eye Irrit.	2	H319
Specific target organ toxicity - single exposure	STOT SE	3	H335
Eye irritation	Eye Irrit.	2A	H319
Skin irritation	Skin Irrit.	2	H315

Discovery and Applications

2-Aminoisobutyric acid (AIB), also known as α-aminoisobutyric acid, is a non-proteinogenic amino acid with the chemical formula (CH3)2C(NH2)COOH. AIB is characterized by a unique structure with two methyl groups attached to the α carbon, making it one of the simplest amino acids with a tertiary α carbon.

The discovery of 2-aminoisobutyric acid dates back to the early studies of amino acids and peptides. AIB occurs naturally in certain peptide antibiotics such as alamethicin and in some microbial metabolites. Its synthesis involves simple methods including the Strecker synthesis, using acetone as a starting material, reaction with ammonia and hydrocyanic acid, followed by hydrolysis to produce AIB.

AIB is widely used in peptide synthesis and research. Due to its steric hindrance and rigidity, its incorporation into peptides produces significant conformational effects. This makes AIB a valuable tool for studying peptide structure and stability and for designing peptides with specific secondary structures such as helices and turns.

In pharmaceutical research, AIB-containing peptides have shown potential therapeutic properties. For example, peptides containing AIB residues can exhibit greater resistance to enzymatic degradation, resulting in enhanced stability and prolonged activity in biological systems. This makes AIB an essential component of peptide drug design.

AIB is used to develop synthetic biomaterials and biopolymers. Its unique structural properties facilitate the formation of materials with specific mechanical and chemical properties. These materials can be used in a variety of applications, including drug delivery systems, tissue engineering, and scaffolds for cell growth.

In the agricultural sector, AIB derivatives are explored for use as plant growth regulators and crop protection. Their ability to influence plant metabolic pathways makes them candidate materials for improving crop yield and resilience.

AIB plays an important role in protein engineering research. By introducing AIB into protein sequences, researchers can study the effects of conformational constraints on protein folding and function. This can lead to the design of proteins with enhanced stability and desired properties for industrial and medical applications.

AIB is a model compound for studying the behavior of amino acids and peptides under different conditions. Its simplicity and well-defined structure make it an ideal subject for studying the fundamental principles of organic and bioorganic chemistry.

Although 2-aminoisobutyric acid is generally considered safe, proper laboratory practices should be followed when handling this substance. It should be stored in a cool, dry place and handled with appropriate personal protective equipment to avoid ingestion, inhalation, or contact with skin and eyes.

References

1964. BACTERIAL METABOLISM OF 2-METHYLALANINE. Journal of Bacteriology, 88(5).
DOI: 10.1128/jb.88.5.1296-1303.1964

2003. Prevention of Peptide Fibril Formation in an Aqueous Environment by Mutation of a Single Residue to Aib. Biochemistry, 42(12).
DOI: 10.1021/bi026856t

2008. Studies on the Selective Trifluoroacetolytic Scission of Native Peptaibols and Model Peptides Using HPLC and ESI-CID-MS. Chemistry & Biodiversity, 5(11).
DOI: 10.1002/cbdv.200890200