Leucine

Chemical structure of Leucine
Leucine
Systematic (IUPAC) name
(S)-2-amino-4-methyl-pentanoic acid
Identifiers
CAS number	61-90-5
PubChem	6106
Chemical data
Formula	C6H13NO2
Molar mass	131.18 g/mol
SMILES	CC(C)C[C@H](N)C(O)=O
Complete data

Leucine (abbreviated as Leu or L) is an α-amino acid with the chemical formula HO₂CCH(NH₂)CH₂CH(CH₃)₂. It is an essential amino acid, which means that humans cannot synthesise it. Its codons are UUA, UUG, CUU, CUC, CUA, and CUG. With a hydrocarbon side chain, leucine is classified as a hydrophobic amino acid.

Biosynthesis

As an essential amino acid, leucine is not synthesized in animals, hence it must be ingested, usually as a component of proteins. It is synthesized in plants and microorganisms via several steps starting from pyruvic acid. The initial part of the pathway also leads to valine. The intermediate α-ketovalerate is converted to α-isopropylmalate and then β-isopropylmalate, which is dehydrogenated to α-ketoisocaproate, which in the final step undergoes reductive amination. Enzymes involved in a typical leucine biosynthesis include

• Acetolactate synthase,
• Acetohydroxy acid isomeroreductase,
• Dihydroxyacid dehydratase,
• α-Isopropylmalate synthase,
• α-Isopropylmalate isomerase,
• Leucine aminotransferase.

See also

• Photo-reactive leucine

External links

• Leucine biosynthesis
• Leucine content in food
• Computational Chemistry Wiki
• Leucine prevents muscle loss in rats
• Leucine helps regulate appetite in rats

<tr bgcolor="#ccccff"><td colspan="3" align="center">Major families of biochemicals</td></tr><tr><td colspan="3" style="text-align: center;">Peptides | Amino acids | Nucleic acids | Carbohydrates | Nucleotide sugars | Lipids | Terpenes | Carotenoids | Tetrapyrroles | Enzyme cofactors | Steroids | Flavonoids | Alkaloids | Polyketides | Glycosides</td></tr><tr bgcolor="pink"><td style="white-space: nowrap; width: 10%; color: pink;">Analogues of nucleic acids:</td><td align="center">The 20 Common Amino Acids ("dp" = data page)</td><td style="white-space: nowrap; width: 10%; color: pink;">Analogues of nucleic acids:</td></tr>