Taurine, or 2-aminoethanesulfonic acid, is an organic acid. It is also a major constituent of bile and can be found in lower amounts in the tissues of many animals including humans. Taurine is a derivative of the sulfur-containing (sulfhydryl) amino acid, cysteine. Taurine is the only known naturally occurring sulfonic acid.
Taurine is named after the Latin taurus, which means bull or ox, as it was first isolated from ox bile in 1827 by Austrian scientists Friedrich Tiedemann and Leopold Gmelin. It is often called an amino acid, even in scientific literature, but as it lacks a carboxyl group it is not strictly an amino acid. It does contain a sulfonate group and may be called an amino sulfonic acid. Small polypeptides have been identified which contain taurine but to date no aminoacyl tRNA synthetase has been identified as specifically recognizing taurine and capable of incorporating it onto a tRNA.
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