Norleucine
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| Names | |
|---|---|
| Preferred IUPAC name
(2S)-2-Aminohexanoic acid | |
| Other names
Caprine
Glycoleucine | |
| Identifiers | |
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3D model (JSmol)
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| 1721748 | |
| ChEBI | |
| ChemSpider | |
| DrugBank | |
| ECHA InfoCard | 100.009.512 |
| EC Number |
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| 464584 | |
| KEGG | |
| MeSH | Norleucine |
PubChem CID
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| RTECS number |
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| UNII | |
CompTox Dashboard (EPA)
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| Properties | |
| C6H13NO2 | |
| Molar mass | 131.175 g·mol−1 |
| Melting point | 301 °C (574 °F; 574 K) (decomposes) [3] |
| 16 g/L at 23 °C [1] | |
| Acidity (pKa) | 2.39 (carboxyl), 9.76 (amino)[2] |
| Related compounds | |
Related Aminoacids
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Norvaline (2-amino-pentanoic) Aminocaproic acid (6-amino-hexanoic) Leucine (2-amino-4-methyl-pentanoic) Isoleucine (2-amino-3-methyl-pentanoic) Lysine (2,6-diamino-hexanoic) |
Related compounds
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Caproic acid (hexanoic) |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Norleucine[a] (abbreviated as Nle) is an amino acid with the formula CH3(CH2)3CH(NH2)CO2H. A systematic name for this compound is 2-aminohexanoic acid. The compound is an isomer of the more common amino acid leucine. Like most other α-amino acids, norleucine is chiral. It is a white, water-soluble solid.
Occurrence
[edit]Together with norvaline, norleucine is found in small amounts in some bacterial strains where its concentration can approach millimolar. Its biosynthesis has been examined. It arises via the action of 2-isopropylmalate synthase on α-ketobutyrate. The incorporation of Nle into peptides reflects the imperfect selectivity of the associated aminoacyl-tRNA synthetase. In Miller–Urey experiments probing prebiotic synthesis of amino acids, norleucine and especially norvaline are formed.[6]
Uses
[edit]It is nearly isosteric with methionine, even though it does not contain sulfur.[7] For this reason, norleucine has been used to probe the role of methionine in Amyloid-β peptide (AβP) the central constituent of senile plaques in Alzheimer's disease. A study showed that with the substitution of the methionine at the 35 position with norleucine the neurotoxic effects of the Aβ peptides were completely negated.[8]
See also
[edit]- Leucines, description of the isomers of leucine
- norvaline, isomer of valine that has similar biochemistry to that of norleucine.
Notes
[edit]References
[edit]- ^ Sicherheitsdatenblatt Acros.[permanent dead link]
- ^ Dawson, R.M.C., et al., Data for Biochemical Research, Oxford, Clarendon Press, 1959.
- ^ Hermann Römpp, Jürgen Falbe und Manfred Regitz: Römpp Lexikon Chemie, 9. Auflage, Georg Thieme Verlag, Stuttgart 1992.
- ^ "Nomenclature and Symbolism For Amino Acids and Peptides". Pure and Applied Chemistry. 56 (5): 595–624. 1984. doi:10.1351/pac198456050595.
- ^ "Nomenclature and Symbolism for Amino Acids and Peptides – Symbols for Amino Acids – 'Nor' amino acids". iupac.qmul.ac.uk. Retrieved 31 May 2025.
- ^ Alvarez-Carreno, Claudia; Becerra, Arturo; Lazcano, Antonio "Norvaline and Norleucine May Have Been More Abundant Protein Components during Early Stages of Cell Evolution" Origins of Life and Evolution of Biospheres 2014, volume 43, 363-375. doi:10.1007/s11084-013-9344-3
- ^ Moroder, Luis "Isosteric replacement of sulfur with other chalcogens in peptides and proteins" Journal of Peptide Science 2005, volume 11, 187-214. doi:10.1002/psc.654
- ^ Clementi, ME & Misiti, F (Nov 2005). "Substitution of methionine 35 inhibits apoptotic effects of Abeta(31-35) and Abeta(25-35) fragments of amyloid-beta protein in PC12 cells". Med. Sci. Monit. 11 (11): BR381-5. PMID 16258386.