Glucuronidation (WP1241)

Mus musculus

Metabolism of xenobiotic compounds consists of phase I and a phase II biotransformation reactions, being compound modification and conjugation reactions respectively. In phase I biotransformation, the compound is modificated via oxidation, reduction, hydrolysis, or other minor reactions, to reveal a reactive group to which a conjugation molecule can react to. In phase II, a small conjugation molecule reacts with the phase I modified molecule, producing a much more water-soluble molecule that can be excreted more easily. Glucuronidation is a phase II biotransformation reaction in which glucuronide acts as a conjugation molecule and binds to a substrate via the catalysis of glucuronosyltransferases. First, in a series of reactions the cosubstrate uridine diphosphate glucuronic acid (UDPGA) is formed. The glucuronosyltransferases (UGTs) then catalyze the transfer of glucuronic acid from UDPGA to a substrate resulting in a glucuronidated substrate and leaving uridine 5'-diphosphate. UGTs are a very broad and divers group of enzymes and count as the most significant group of conjugation enzymes in xenobiotic metabolism, qualitatively because glucuronic acid can be coupled to a large diversity of functional groups and quantitatively because of the large and divers number of substrates that are formed.


Christine Chichester and Egon Willighagen


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Mus musculus



Pathway Ontology

glucuronidation conjugation pathway


Label Type Compact URI Comment
Adenosine 3',5'-diphosphate Metabolite hmdb:HMDB0000061
2H+ Metabolite chebi:15378
Glucose 6-phosphate Metabolite hmdb:HMDB0001401
Uridine 5'-diphosphate Metabolite hmdb:HMDB0000295
NAD Metabolite hmdb:HMDB0000902
Water Metabolite hmdb:HMDB0002111
Adenosine triphosphate Metabolite hmdb:HMDB0000538
NADH Metabolite hmdb:HMDB0001487
Uridine diphosphate glucose Metabolite hmdb:HMDB0000286
Phosphate Metabolite hmdb:HMDB0001429
Glucose 1-phosphate Metabolite hmdb:HMDB0001586
Uridine diphosphate glucuronic acid Metabolite hmdb:HMDB0000935
Phosphate Metabolite hmdb:HMDB0001429
Uridine triphosphate Metabolite hmdb:HMDB0000285
D-Glucose Metabolite hmdb:HMDB0000122
Ugp2 GeneProduct ensembl:ENSMUSG00000001891
Pgm3 GeneProduct ensembl:ENSMUSG00000056131
PGM5 GeneProduct ncbigene:226041
Pgm1 GeneProduct ensembl:ENSMUSG00000029171
Hk1 GeneProduct ensembl:ENSMUSG00000037012
Ugdh GeneProduct ensembl:ENSMUSG00000029201
Pgm2 GeneProduct ensembl:ENSMUSG00000025791
Ugt1a5 GeneProduct ncbigene:394433
Ugt1a8 GeneProduct mgi:MGI:3576090
Ugt2a3 GeneProduct ncbigene:72094
Ugt2b1 GeneProduct ncbigene:71773
Ugt2b34 GeneProduct ncbigene:100727
Ugt1a10 GeneProduct ncbigene:394430
Ugt1a5 GeneProduct ncbigene:394433
Ugt2a1 GeneProduct ncbigene:94215
Ugt1a1 GeneProduct ncbigene:394436
Ugt1a9 GeneProduct ncbigene:434493
Ugt2a2 GeneProduct ncbigene:552899
Ugt1a2 GeneProduct ncbigene:22236


  1. The biochemistry of drug metabolism--an introduction: part 4. reactions of conjugation and their enzymes. Testa B, Krämer SD. Chem Biodivers. 2008 Nov;5(11):2171–336. PubMed Europe PMC Scholia
  2. Androgen-stimulated UDP-glucose dehydrogenase expression limits prostate androgen availability without impacting hyaluronan levels. Wei Q, Galbenus R, Raza A, Cerny RL, Simpson MA. Cancer Res. 2009 Mar 15;69(6):2332–9. PubMed Europe PMC Scholia