Threonine

n. essential amino acid

Threonine (abbreviated as Thr or T) is an α-amino acid with the chemical formula HO2CCH(NH2)CH(OH)CH3. Its codons are ACU and ACA. This essential amino acid is classified as polar. Together with serine and tyrosine, threonine is one of three proteinogenic amino acids bearing an alcohol group. The threonine residue is susceptible to numerous posttranslational modifications. The hydroxy side chain can undergo O-linked glycosylation. In addition, threonine residues undergo phosphorylation through the action of a threonine kinase. In its phosphorylated form, it can be referred to as phosphothreonine.
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Threonine /thre·o·nine/ a naturally occurring amino acid essential for human metabolism. thre·o·nine n. Abbr. [more]Threonine - Community and Resources

Noun
1. a colorless crystalline amino acid found in protein; occurs in the hydrolysates of certain proteins; an essential component of human nutrition
(hypernym) essential amino acid

(CH3CH(OH)CH(NH2)COOH) -amino-ß-hydroxybutyric acid.
A naturally occuring amino acid with a hydroxyl group on its side chain. Closely related to serine.