L-aspartate

Aspartic acid

Names
IUPAC names Trivial: Aspartic acid Systematic: 2-Aminobutanedioic acid
Other names Aminosuccinic acid, asparagic acid, asparaginic acid
Identifiers
CAS Number	617-45-8 Y 56-84-8 (L-isomer) N 1783-96-6 (D-isomer) N
3D model (Jmol)	Interactive image Interactive image
ChEBI	CHEBI:22660 Y
ChemSpider	411 Y
ECHA InfoCard	100.000.265
EC Number	200-291-6
KEGG	C16433 Y
PubChem CID	424
UNII	28XF4669EP Y
InChI InChI=1S/C4H7NO4/c5-2(4(8)9)1-3(6)7/h2H,1,5H2,(H,6,7)(H,8,9) Y Key: CKLJMWTZIZZHCS-UHFFFAOYSA-N Y InChI=1/C4H7NO4/c5-2(4(8)9)1-3(6)7/h2H,1,5H2,(H,6,7)(H,8,9) Key: CKLJMWTZIZZHCS-UHFFFAOYAE
SMILES O=C(O)CC(N)C(=O)O C(C(C(=O)O)N)C(=O)O
Properties
Chemical formula	C4H7NO4
Molar mass	133.10 g·mol−1
Appearance	colourless crystals
Density	1.7 g/cm3
Melting point	270 °C (518 °F; 543 K)
Boiling point	324 °C (615 °F; 597 K) (decomposes)
Solubility in water	4.5 g/L
Acidity (pKa)	3.9
Magnetic susceptibility (χ)	-64.2·10−6 cm3/mol
Hazards
Safety data sheet	See: data page
NFPA 704	1 1 0
Supplementary data page
Structure and properties	Refractive index (n), Dielectric constant (εr), etc.
Thermodynamic data	Phase behaviour solid–liquid–gas
Spectral data	UV, IR, NMR, MS
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N  (what is YN ?)
Infobox references

Aspartic acid (abbreviated as Asp or D; encoded by the codons [GAU and GAC]), also known as aspartate, is an α-amino acid that is used in the biosynthesis of proteins. Similar to all other amino acids it contains an amino group and a carboxylic acid. Its α-amino group is in the protonated –NH+
3 form under physiological conditions, while its α-carboxylic acid group is deprotonated −COO⁻ under physiological conditions. Aspartic acid has an acidic side chain (CH₂COOH) which reacts with other amino acids, enzymes and proteins in the body. Under physiological conditions (pH 7.4) in proteins the side chain usually occurs as the negatively charged aspartate form, −COO⁻ . It is a non-essential amino acid in humans, meaning the body can synthesize it as needed.

D-Aspartate is one of two D-amino acids commonly found in mammals.^[3].

In proteins aspartate sidechains are often hydrogen bonded, often as asx turns or asx motifs, which often occur at the N-termini of alpha helices.

Asp's L-isomer is one of the 22 proteinogenic amino acids, i.e., the building blocks of proteins. Asp (and glutamic acid) is classified as acidic, with a pK_a of 3.9, however in a peptide this is highly dependent on the local environment (as with all amino acids), and could be as high as 14. Asp is pervasive in biosynthesis.

Aspartic acid was first discovered in 1827 by Auguste-Arthur Plisson and Étienne Ossian Henry by hydrolysis of asparagine, which had been isolated from asparagus juice in 1806. Their original method used lead hydroxide, but various other acids or bases are more commonly used instead.