Alanine

General
Chemical name	(S)-2-Aminopropanoic acid
Synonyms	α-Alanine Ritalanine
Abbreviations	A, Ala
Chemical formula	C3H7NO2
Physical properties
Molecular mass	89.0932 g/mol
ρ	1.401 g/cm3
Tm	297 °C
Tb	? °C
Chemical properties
pI	6.00
pKa	2.33 9.71
H-bond acceptors	3
H-bond donors	2
Tautomers	none
Miscellaneous
CAS [1]	56-41-7
EINECS	200-273-8
PubChem [2]	602

Alanine (Ala) is an α-AA. It exists as two distinct enantiomers - L-Ala and D-Ala. L-Ala is one of the 20 AAs most widely used in protein synthesis, second to Leu, accounting for 7.8% of the primary structure in a sample of 1,150 proteins (Doolittle, 1989). D-Ala occurs in bacterial cell walls and in some peptide antibiotics.

Structure

Ala's α-carbon atom is substituted with a methyl group (-CH₃), making it one of the simplest α-amino acids with respect to molecular structure and also resulting in Ala being classified as an aliphatic AA.

Synthesis

Ala is most commonly made by transfer of an amine group to pyruvate. Because transamination reactions are readily reversible, Ala can be easily formed from Pyr and thus has close links to metabolic pathways such as Glycolysis, Gluconeogenesis, and TCAC.

Function

The methyl group of Ala is very non-reactive, and is thus rarely directly involved in protein function. However Ala can play a role in substrate recognition or specificity, particularly in interactions with other non-reactive atoms such as carbon.

References

Doolittle RF (1989). "Redundancies in protein sequences" in Prediction of Protein Structures and the Principles of Protein Conformation. (Fasman GD, ed.), pp 599-623, Plenum Press, New York.

External links

• Computational Chemistry Wiki