Allothreonine is an

amino acid Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although over 500 amino acids exist in nature, by far the most important are the 22 α-amino acids incorporated into proteins. Only these 22 a ...

with the formula . It is the

diastereomer In stereochemistry, diastereomers (sometimes called diastereoisomers) are a type of stereoisomer. Diastereomers are defined as non-mirror image, non-identical stereoisomers. Hence, they occur when two or more stereoisomers of a compound have di ...

of the amino acid

threonine Threonine (symbol Thr or T) is an amino acid that is used in the biosynthesis of proteins. It contains an α-amino group (which is in the protonated −NH form when dissolved in water), a carboxyl group (which is in the deprotonated −COO− ...

. Like most other amino acids, allothreonine is a water-soluble colorless solid. Although not one of the

proteinogenic amino acid Proteinogenic amino acids are amino acids that are incorporated biosynthetically into proteins during translation from RNA. The word "proteinogenic" means "protein creating". Throughout known life, there are 22 genetically encoded (proteinogenic) ...

s, it has often been the subject for the synthesis of novel proteins using an

expanded genetic code An expanded genetic code is an artificially modified genetic code in which one or more specific codons have been re-allocated to encode an amino acid that is not among the 22 common naturally-encoded proteinogenic amino acids. The key prerequisit ...

Racemic In chemistry, a racemic mixture or racemate () is a mixture that has equal amounts (50:50) of left- and right-handed enantiomers of a chiral molecule or salt. Racemic mixtures are rare in nature, but many compounds are produced industrially as r ...

allothreonine can be produced in the laboratory from bromomethoxybutyric acid.

Structure

Threonine has R, S stereochemistry at carbons 2 and 3 for the naturally occurring stereoisomer and S, R stereochemistry for its enantiomer. Allothreonine has S, S stereochemistry at carbons 2 and 3 in the natural stereoisomer, but R, R in the very rare enantiomer.

Occurrence

Katanosins are a group of potent

antibiotics An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting pathogenic bacteria, bacterial infections, and antibiotic medications are widely used in the therapy ...

contain allothreonine. Peptides containing the allothreonine residue have also been isolated from natural source.{{cite journal , doi=10.1021/jo1025145 , title=Solid Phase Synthesis of Globomycin and SF-1902 A₅ , date=2011 , last1=Sarabia , first1=Francisco , last2=Chammaa , first2=Samy , last3=García-Ruiz , first3=Cristina , journal=The Journal of Organic Chemistry , volume=76 , issue=7 , pages=2132–2144 , pmid=21366318

References

Alpha-Amino acids Ketogenic amino acids