Glukuronosiltransferase: Perbedaan antara revisi
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''''''Uridin 5'-difosfo-glukuronosyltransferase'''''' ([[Uridin difosfat|UDP]]-glukuronosiltransferase, UGT)<ref>{{en}} {{cite web
| url = http://www.chem.qmul.ac.uk/iubmb/enzyme/EC2/4/1/17.html
| title = EC 2.4.1.17
| accessdate = 2011-05-18
| work = Queen Mary University of London
| archive-date = 2016-11-12
| archive-url = https://web.archive.org/web/20161112133630/http://www.chem.qmul.ac.uk/iubmb/enzyme/EC2/4/1/17.html
| dead-url = no
}}</ref> adalah [[enzim]] [[fase]] II yang meng[[katalis]] reaksi [[konjugasi]] [[gugus fungsional|gugus]] [[glukuronil]] dari [[asam glusuronat|''uridin 5'-asam difosfoglukuronat'']] ke berbagai [[substrat]] [[nukleofilik]] eksogenus dan endogenus untuk menghasilkan [[senyawa organik|senyawa]] [[glukuronida]] yang mempunyai kadar toksin lebih rendah dan lebih ''polar'' sehingga lebih mudah untuk di[[ekskresi]].<ref>{{en}} {{cite web
| url = http://jn.nutrition.org/content/137/4/890.full
| title = UGT1A1 Polymorphism Is Associated with Serum Bilirubin Concentrations in a Randomized, Controlled, Fruit and Vegetable Feeding Trial
| accessdate = 2011-06-02
| work = Interdisciplinary Graduate Program in Nutritional Sciences, Department of Epidemiology, University of Washington; Jyh-Lurn Chang, Jeannette Bigler, Yvonne Schwarz, Shuying S. Li, Lin Li, Irena B. King, John D. Potter dan Johanna W. Lampe
| archive-date = 2018-01-11
| archive-url = https://web.archive.org/web/20180111215657/http://jn.nutrition.org/content/137/4/890.full
| dead-url = no
}}</ref> [[Substrat]] UGT dapat berupa [[bilirubin]] dan [[estrogen]],<ref>{{en}} {{cite web
| url = http://toxsci.oxfordjournals.org/content/78/1/1.full
| title = Glucuronidation and Susceptibility to Chemical Carcinogenesis
| accessdate = 2011-05-18
| work = Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Illinois; Matthew A. Wallig
| archive-date = 2023-08-06
| archive-url = https://web.archive.org/web/20230806191948/https://academic.oup.com/toxsci/article/78/1/1/1625678
| dead-url = no
}}</ref> khususnya senyawa [[karsinogen]]ik seperti [[fenolik]], [[hidrokarbon]] [[poliaromatik]], [[amina]] [[aromatik]].
Reaksi konjugasi UGT disebut reaksi [[glukuronidasi]], yang biasa terjadi pada [[lintasan metabolisme|lintasan]] [[detoksifikasi]] dengan variasi enzim detoks lain seperti [[sitokrom P450]] dan [[glutathion]] S-[[transferase]]. Glusuronidasi mencegah terjadinya oksidasi terus-menerus pada ''electrophile'' yang lebih lanjut dapat menimbulkan reaksi kimiawi antara [[toksin]] dengan [[DNA]], [[RNA]] dan [[protein]] [[inti sel|inti]] lainnya.<ref>{{en}} {{cite web
| url = http://www.ncbi.nlm.nih.gov/pubmed/1914494
| title = Roles of UDP-glucuronosyltransferases in chemical carcinogenesis
| accessdate = 2011-06-02
| work = Institute of Toxicology, University of Tübingen; Bock KW.
| archive-date = 2023-08-06
| archive-url = https://web.archive.org/web/20230806191938/https://pubmed.ncbi.nlm.nih.gov/1914494/
| dead-url = no
}}</ref> Manusia dengan tingkat glusuronidasi yang rendah, memiliki risiko [[kanker]] yang lebih tinggi, karena [[senyawa organik|senyawa]] hidrokarbon poliaromatik memerlukan konjugasi [[asam glusuronat]] agar dapat menjadi inaktif.
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UGT-1A1 merupakan enzim utama yang berperan pada proses glusuronidasi [[estradiol]],<ref>{{en}} {{cite web
| url = http://cancerres.aacrjournals.org/content/60/4/950.abstract?ijkey=27d089b032d6ea3eddc5f0be99628221cb7e174b&keytype2=tf_ipsecsha
| title = Genetic Polymorphisms in Uridine Diphospho-Glucuronosyltransferase 1A1 and Association with Breast Cancer among African Americans
| accessdate = 2011-05-18
| work = Department of Biology and Center for Cancer Research, Massachusetts Institute of Technology, Department of Epidemiology and Lineberger Comprehensive Cancer Center, University of North Carolina, School of Public Health, Queensland University of Technology; Chantal Guillemette, Robert C. Millikan, Beth Newman, dan David E. Housman
| archive-date = 2023-08-06
| archive-url = https://web.archive.org/web/20230806192007/https://aacrjournals.org/cancerres/article/60/4/950/507129/Genetic-Polymorphisms-in-Uridine-Diphospho
| dead-url = no
}}</ref> dan senyawa endogenus lain seperti bilirubin, steroid seks, [[estriol]] dan 17ß-estradiol, serta senyawa xenobiotik yang berasal dari asupan makanan seperti fenol, [[anthrakuinon]], dan [[flavon]]. Senyawa karsinogen dari asupan makanan seperti ''[[2-amino-1-metil-6-fenilimidakso(4,5-b)piridin]]'' dan [[benzoapirena]] juga ikut terkonjugasi. Aktivitas UGT-1A1 terutama meningkat pada [[kanker payudara]] dan [[hepatokarsinoma]].
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== Kontroversi ==
* {{en}} [http://www.ncbi.nlm.nih.gov/pubmed/12806614 UDP glucuronosyltransferase (UGT1A7) gene polymorphisms increase the risk of chronic pancreatitis and pancreatic cancer] {{Webarchive|url=https://web.archive.org/web/20230806191929/https://pubmed.ncbi.nlm.nih.gov/12806614/ |date=2023-08-06 }}
** {{en}} [http://www.ncbi.nlm.nih.gov/pubmed/16199544 Polymorphisms of UDP-glucuronosyltransferase 1A7 are not involved in pancreatic diseases] {{Webarchive|url=https://web.archive.org/web/20230806191938/https://pubmed.ncbi.nlm.nih.gov/16199544/ |date=2023-08-06 }}
== Rujukan ==
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