isoleucine

n. amino acid which is an essential nutrient occurring in proteins (Biochemistry)

Isoleucine (abbreviated as Ile or I) is an α-amino acid with the chemical formula HO2CCH(NH2)CH(CH3)CH2CH3. It is an 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 hydrophobic amino acid. Together with threonine, isoleucine is one of two common amino acids that have a chiral side chain. Four stereoisomers of isoleucine are possible, including two possible diastereomers of L-isoleucine. However, isoleucine present in nature exists in one enantiomeric form, (2S,3S)-2-amino-3-methylpentanoic acid.
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Isoleucine /iso·leu·cine/ an essential amino acid produced by hydrolysis of fibrin and other proteins; necessary for optimal infant growth and for [more]Isoleucine - Community and Resources

Noun
1. an essential amino acid found in proteins; isomeric with leucine
(hypernym) essential amino acid

((CH3)2CHCH(NH2)COOH) -amino-ß-methylvaleric acid].
A naturally occuring amino acid with a nonpolar side chain.