UGT1A4 transfers GlcA from UDP-GlcA to BIL to form BMG

Stable Identifier
Reaction [transition]
Homo sapiens
bilirubin + UDP-glucuronic acid => bilirubin monoglucuronide + UDP
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Bilirubin (BIL) is a breakdown product of heme. Its accumulation in the blood can be fatal. It is highly lipophilic and thus requires conjugation to become more water soluble to aid excretion. Both UGT1A1 tetramer and UGT1A4 can transfer glucuronic acid (GlcA) to bilirubin to form either its monoglucuronide (BMG) or diglucuronide (BDG) conjugates (Bosma et al. 1994, Ritter et al. 1992, Peters & Jansen 1986, Gorden et al. 1983, Choudhury et al. 1981, Fevery et al. 1971).

Literature References
PubMed ID Title Journal Year
4639028 Bilirubin conjugates in bile of man and rat in the normal state and in liver disease

Michiels, R, Van, Damme B, Heirwegh, KP, Fevery, J, De Groote, J

J Clin Invest 1972
6654901 The hepatic microsomal formation of bilirubin diglucuronide

Goresky, CA, Gordon, ER, Sommerer, U

J Biol Chem 1983
6796486 Bilirubin mono- and diglucuronide formation by human liver in vitro: assay by high-pressure liquid chromatography

Shouval, R, Wu, G, Chowdhury, JR, Chowdhury, NR, Arias, IM

Hepatology 1981
1339448 A novel complex locus UGT1 encodes human bilirubin, phenol, and other UDP-glucuronosyltransferase isozymes with identical carboxyl termini

Owens, IS, Chen, F, Ritter, JK, Kimura, S, Sheen, YY, Yeatman, MT, Tran, HM

J. Biol. Chem. 1992
3082969 Microsomal UDP-glucuronyltransferase-catalyzed bilirubin diglucuronide formation in human liver

Jansen, PL, Peters, WH

J Hepatol 1986
8027054 Bilirubin UDP-glucuronosyltransferase 1 is the only relevant bilirubin glucuronidating isoform in man

Goldhoorn, B, Bosma, PJ, Jansen, PL, Oude, Elferink R, Bakker, C, Seppen, J, Chowdhury, JR, Chowdhury, NR

J Biol Chem 1994
Event Information
Go Biological Process
Catalyst Activity

glucuronosyltransferase activity of UGT1A4 [endoplasmic reticulum membrane]

Orthologous Events
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