L-Aspartic Acid

Aspartic acid (abbreviated as D-AA, Asp, or D) is an α-amino acid with the chemical formulaHOOCCH(NH2)CH2COOH. The carboxylate anion and salts of aspartic acid are known as aspartate. The L-isomer of aspartate is one of the 22 proteinogenic amino acids, i.e., the building blocks of proteins. Its codons are GAU and GAC.

Aspartic acid is, together with glutamic acid, classified as an acidic amino acid with a pKa of3.9, however, in a peptide, the pKa is highly dependent on the local environment. A pKa as high as 14 is not at all uncommon. Aspartate is pervasive in biosynthesis. As with all amino acids, the presence of acid protons depends on onthe residue's local chemical environment and the of the solution.