Α-Aminobutyric acid

α-Aminobutyric acid
Names
IUPAC name
Homoalanine
Systematic IUPAC name
2-Aminobutanoic acid
Other names
2-Aminobutyric acid; α-Aminobutanoic acid; Ethylglycine;
2-Azaniumylbutanoate
Identifiers
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.018.742
UNII
  • InChI=1S/C4H9NO2/c1-2-3(5)4(6)7/h3H,2,5H2,1H3,(H,6,7) Y
    Key: QWCKQJZIFLGMSD-UHFFFAOYSA-N Y
  • InChI=1/C4H9NO2/c1-2-3(5)4(6)7/h3H,2,5H2,1H3,(H,6,7)
    Key: QWCKQJZIFLGMSD-UHFFFAOYAG
  • O=C(O)C(N)CC
Properties
C4H9NO2
Molar mass 103.12 g/mol
Appearance white solid
Melting point 305 °C (581 °F; 578 K)
Acidity (pKa) 2.55 (carboxyl), 9.60 (amino)
−62.1·10−6 cm3/mol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y verify (what is YN ?)
Infobox references

α-Aminobutyric acid (AABA), also known as homoalanine in biochemistry, is a non-proteinogenic alpha amino acid with chemical formula C4H9NO2. The straight two carbon side chain is one carbon longer than alanine, hence the prefix homo-. The conjugate base of α-aminobutyric acid is the carboxylate α-aminobutyrate.

Homoalanine is biosynthesized by transaminating oxobutyrate, a metabolite in isoleucine biosynthesis. It is used by nonribosomal peptide synthases. One example of a nonribosomal peptide containing homoalanine is ophthalmic acid, which was first isolated from calf lens.

α-Aminobutyric acid is one of the three isomers of aminobutyric acid. The two other are the neurotransmitter γ-aminobutyric acid (GABA) and β-aminobutyric acid (BABA) which is known for inducing plant disease resistance.

This amino acid has been detected in meteorites.