Isocitric acid

Isocitric acid is a structural isomer of citric acid. Salts and esters of isocitric acid are known as isocitrates. The isocitrate anion is a substrate of the citric acid cycle. Isocitrate is formed from citrate with the help of the enzyme aconitase, and is acted upon by isocitrate dehydrogenase.

Isocitric acid

Names
IUPAC name 1-Hydroxypropane-1,2,3-tricarboxylic acid
Identifiers
CAS Number	320-77-4^Y
3D model (JSmol)	Interactive image
ChEBI	CHEBI:30887^Y
ChEMBL	ChEMBL539669^Y
ChemSpider	1161^Y
DrugBank	DB01727^N°
ECHA InfoCard	100.005.713
KEGG	C00311^Y
MeSH	Isocitrate
PubChem CID	1198
UNII	9RW6G5D4MQ^Y
CompTox Dashboard (EPA)	DTXSID60861871
InChI InChI=1S/C6H8O7/c7-3(8)1-2(5(10)11)4(9)6(12)13/h2,4,9H,1H2,(H,7,8)(H,10,11)(H,12,13)^Y Key: ODBLHEXUDAPZAU-UHFFFAOYSA-N^Y InChI=1/C6H8O7/c7-3(8)1-2(5(10)11)4(9)6(12)13/h2,4,9H,1H2,(H,7,8)(H,10,11)(H,12,13) Key: ODBLHEXUDAPZAU-UHFFFAOYAX
SMILES O=C(O)C(CC(=O)O)C(O)C(=O)O
Properties
Chemical formula	C6H8O7
Molar mass	192.124
Melting point	105 °C (221 °F; 378 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N verify (what is ^YN ?)
Infobox references

Isocitric acid is commonly used as a marker to detect the authenticity and quality of fruit products, most often citrus juices. In authentic orange juice, for example, the ratio of citric acid to D-isocitric acid is usually less than 130. An isocitric acid value higher than this may be indicative of fruit juice adulteration.[1]

Interactive pathway map

Click on genes, proteins and metabolites below to link to respective articles. [§ 1]

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|{{{bSize}}}px|alt=TCA Cycle edit]]

TCA Cycle edit

1. The interactive pathway map can be edited at WikiPathways: "TCACycle_WP78".

See also

• Citric Acid
• Tartaric Acid
• Malic Acid

References

1. Saavedra, L.; Garcia, A.; Barbas, C. (9 June 2000). "Development and validation of a capillary electrophoresis method for direct measurement of isocitric, citric, tartaric and malic acids as adulteration markers in orange juice". Journal of Chromatography A. 881 (1–2): 395–401. doi:10.1016/s0021-9673(00)00258-2. PMID 10905722.