Isoleucine





Chemical structure of L-isoleucine

Isoleucine

Systematic (IUPAC) name
(2S,3S)-2-amino-3-methylpentanoic acid
Identifiers
CAS number 73-32-5
PubChem         791
Chemical data
Formula O2 
Molar mass 131.18 g/mol
SMILES CC[C@H](C)[C@H](N)C(O)=O
Complete data

Isoleucine (abbreviated as Ile or I)[1] is an α-essential amino acid, which means that humans cannot synthesize it, so it must be part of our diet. Its codons are AUU, AUC and AUA.

With a hydrocarbon side chain, isoleucine is classified as a diastereomers of L-isoleucine. However, isoleucine present in nature exists in one enantiomeric form, (2S,3S)-2-amino-3-methylpentanoic acid.

Biosynthesis

As an essential amino acid, isoleucine is not synthesized in animals, hence it must be ingested, usually as a component of proteins. In plants and microorganisms, it is synthesized via several steps, starting from alpha-ketoglutarate. Enzymes involved in this biosynthesis include:[2]

  1. Acetolactate synthase
  2. Acetohydroxy acid isomeroreductase
  3. Dihydroxyacid dehydratase
  4. Valine aminotransferase

Isomers of isoleucine



Forms of Isoleucine
Common name: isoleucine D-isoleucine L-isoleucine DL-isoleucine allo-D-isoleucine allo-L-isoleucine allo-DL-isoleucine
Synonyms: (R)-Isoleucine L(+)-Isoleucine (R*,R*)-isoleucine alloisoleucine
PubChem:CID 791CID 94206 CID 6306 CID 76551
EINECS number:207-139-8 206-269-2 200-798-2 216-143-9 216-142-3 221-464-2
CAS number:443-79-8 319-78-8 73-32-5 1509-35-9 1509-34-8 3107-04-8

Synthesis

Isoleucine can be synthesized in a multistep procedure starting from 2-bromobutane and diethylmalonate.[3] Synthetic isoleucine was originally reported in 1905.[4]

References

  1. ^ IUPAC-IUBMB Joint Commission on Biochemical Nomenclature. Nomenclature and Symbolism for Amino Acids and Peptides. Recommendations on Organic & Biochemical Nomenclature, Symbols & Terminology etc. Retrieved on 2007-05-17.
  2. ^ Nelson, D. L.; Cox, M. M. "Lehninger, Principles of Biochemistry" 3rd Ed. Worth Publishing: New York, 2000. ISBN 1-57259-153-6.
  3. ^ Marvel, C. S. “dl-Isoleucine” Organic Syntheses, Collected Volume 3, p.495 (1955). http://www.orgsyn.org/orgsyn/pdfs/CV3P0495.pdf
  4. ^ Bouveault and Locquin, Compt. rend., 141, 115 (1905).
 
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Isoleucine". A list of authors is available in Wikipedia.