Glucuronic acid

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Structural formula
Structure of glucuronic acid
β- D -glucuronic acid
General
Surname Glucuronic acid
other names

(2 S , 3 S , 4 S , 5 R , 6 R ) -3,4,5,6-tetrahydroxytetrahydropyran-2-carboxylic acid

Molecular formula C 6 H 10 O 7
Brief description

colorless solid

External identifiers / databases
CAS number
  • 576-37-4
  • 6556-12-3 ( D -glucuronic acid)
EC number 229-486-4
ECHA InfoCard 100.026.807
PubChem 65041
ChemSpider 58552
DrugBank DB03156
Wikidata Q409216
properties
Molar mass 194.14 g mol −1
Physical state

firmly

Melting point

165 ° C

pK s value

3.18

solubility

soluble in water and ethanol

safety instructions
GHS labeling of hazardous substances
no GHS pictograms
H and P phrases H: no H-phrases
P: no P-phrases
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Glucuronic acid (or glucuronate ), often abbreviated as GlcA in biochemical terms , is the uronic acid of D - glucose , from which it differs in the oxidation state on the sixth carbon, where a carboxy group is present instead of a hydroxyl group . It is found in plant and animal organisms.

In human metabolism, the substance is used in particular for detoxification (phase II of biotransformation ): Toxins and drugs or steroid hormones such as estrogen are made water-soluble by combining with glucuronic acid ( glucuronidation ); these conjugates can then be excreted more easily. Glucuronic acid is also a component of glycosaminoglycans ( cartilage ). It is also the starting point for the biosynthesis of ascorbic acid .

The acid dissolves in water and alcohol , its melting point is 165 ° C. Mutarotation is seen in the crystalline form .

physiology

α- D -glucuronic acid in ( 1 ) Tollens / Fischer, ( 2 ) Haworth , ( 3 ) armchair representation and ( 4 ) stereochemical view

The biosynthesis of glucuronic acid starts from UDP-glucose , which is produced during glycogen build-up. This is converted to UDP-glucuronate with the help of UDP-glucose-6-dehydrogenase . When bound to UDP, glucuronic acid is easily passed on to other ligands by means of UDP-glucuronosyltransferase , which increases their solubility in water. To build up the cartilage, UDP-glucuronate has to be transported into the endoplasmic reticulum with the help of the UDP-glucuronate transporter , where it is converted to UDP-α- D -xylose by means of UDP-glucuronate decarboxylase . β- glucuronidase catalyzes the breakdown of inositol and dermatan or keratan sulfates to pure glucuronic acid (this is then excreted).

Web links

Wikibooks: Biochemistry and Pathobiochemistry: Uronic Acid Metabolism  - Learning and Teaching Materials

Individual evidence

  1. ↑ a b Data sheet glucuronic acid from Acros, accessed on July 11, 2007.
  2. ↑ a b Entry on d-glucuronic acid. In: Römpp Online . Georg Thieme Verlag, accessed on December 25, 2014.
  3. ↑ Data sheet D-Glucuronic acid from Sigma-Aldrich , accessed on May 7, 2017 ( PDF ).