Valine
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Names | |||
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IUPAC name
Valine
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Other names
2-Amino-3-methylbutanoic acid
2-Aminoisovaleric acid Valic acid | |||
Identifiers | |||
3D model (
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ChEBI |
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ChEMBL |
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ChemSpider | |||
DrugBank |
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ECHA InfoCard
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100.000.703 | ||
EC Number |
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IUPHAR/BPS |
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KEGG |
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PubChem CID
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UNII |
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CompTox Dashboard (EPA)
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Properties[3] | |||
C5H11NO2 | |||
Molar mass | 117.148 g·mol−1 | ||
Density | 1.316 g/cm3 | ||
Melting point | 298 °C (568 °F; 571 K) (decomposition) | ||
soluble, 85 g/L [1] | |||
Acidity (pKa) | 2.32 (carboxyl), 9.62 (amino)[2] | ||
-74.3·10−6 cm3/mol | |||
Supplementary data page | |||
Valine (data page) | |||
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Valine (symbol Val or V)
History and etymology
Valine was first isolated from
Nomenclature
According to IUPAC, carbon atoms forming valine are numbered sequentially starting from 1 denoting the carboxyl carbon, whereas 4 and 4' denote the two terminal methyl carbons.[8]
Metabolism
Source and biosynthesis
Valine, like other branched-chain amino acids, is synthesized by bacteria and plants, but not by animals.
- Acetolactate synthase (also known as acetohydroxy acid synthase)
- Acetohydroxy acid isomeroreductase
- Dihydroxyacid dehydratase
- Valine aminotransferase
Degradation
Like other branched-chain amino acids, the catabolism of valine starts with the removal of the amino group by
Synthesis
- HO2CCH2CH(CH3)2 + Br2 → HO2CCHBrCH(CH3)2 + HBr
- HO2CCHBrCH(CH3)2 + 2 NH3 → HO2CCH(NH2)CH(CH3)2 + NH4Br
Medical significance
Metabolic diseases
The degradation of valine is impaired in the following metabolic diseases:
- Combined malonic and methylmalonic aciduria (CMAMMA)
- Maple syrup urine disease (MSUD)
- Methylmalonic acidemia
- Propionic acidemia
Insulin resistance
Lower levels of serum valine, like other branched-chain amino acids, are associated with weight loss and decreased insulin resistance: higher levels of valine are observed in the blood of diabetic mice, rats, and humans.[14] Mice fed a BCAA-deprived diet for one day had improved insulin sensitivity, and feeding of a valine-deprived diet for one week significantly decreases blood glucose levels.[15] In diet-induced obese and insulin resistant mice, a diet with decreased levels of valine and the other branched-chain amino acids resulted in a rapid reversal of the adiposity and an improvement in glucose-level control.[16] The valine catabolite 3-hydroxyisobutyrate promotes insulin resistance in mice by stimulating fatty acid uptake into muscle and lipid accumulation.[17] In mice, a BCAA-restricted diet decreased fasting blood glucose levels and improved body composition.[18]
Hematopoietic stem cells
Dietary valine is essential for hematopoietic stem cell (HSC) self-renewal, as demonstrated by experiments in mice.[19] Dietary valine restriction selectively depletes long-term repopulating HSC in mouse bone marrow. Successful stem cell transplantation was achieved in mice without irradiation after 3 weeks on a valine restricted diet. Long-term survival of the transplanted mice was achieved when valine was returned to the diet gradually over a 2-week period to avoid refeeding syndrome.
See also
References
- ^ "Physicochemical Information". emdmillipore. 2022. Retrieved 17 November 2022.
- OCLC 859821178.
- ISBN 0-8493-0462-8.
- ^ "Nomenclature and Symbolism for Amino Acids and Peptides". IUPAC-IUB Joint Commission on Biochemical Nomenclature. 1983. Archived from the original on 9 October 2008. Retrieved 5 March 2018.
- ^ "Valine". Encyclopædia Britannica Online. Retrieved 6 December 2015.
- ^ "Valine". Merriam-Webster Online Dictionary. Retrieved 6 December 2015.
- ^ "Valeric acid". Merriam-Webster Online Dictionary. Retrieved 6 December 2015.
- ISBN 978-0-85186-144-9.
- OCLC 945482059.
- ISBN 978-0-309-08537-3.
- ISBN 1-57259-153-6..
- OCLC 42290721.
- ^ Marvel CS (1940). "dl-Valine". Organic Syntheses. 20: 106; Collected Volumes, vol. 3, p. 848..
- PMID 25287287.
- PMID 24684822.
- PMID 29266268.
- PMID 26950361.
- PMID 27346343.
- S2CID 45815137.
External links