What is function of uridine diphosphate Glucuronosyltransferase?

Uridine 5′-diphospho (UDP)-glucuronosyltransferases (UGTs) are a superfamily of phase II enzymes which have roles in the conjugation of xenobiotics or endogenous compounds, including drugs and bilirubin, with glucuronic acid to make them easier to excrete.

Where is UDP Glucuronyl transferase?

UDP-glucuronosyltransferase: A liver enzyme essential to the disposal of bilirubin (the chemical that results from the normal breakdown of hemoglobin from red blood cells).

What does lack of UDP Glucuronosyl transferase cause?

The deficiency of this enzyme (UDP-glucuronosyltransferase) results in a condition called Gilbert’s disease in which there are mild elevations of bilirubin pigment in the blood. The elevated bilirubin pigment can sometimes cause mild yellowing (jaundice) of the eyes.

Which enzyme is responsible for the conjugation of bilirubin?

Bilirubin is conjugated within the hepatocyte to glucuronic acid by a family of enzymes, termed uridine-diphosphoglucuronic glucuronosyltransferase (UDPGT).

What is UDP enzyme?

The UDP-glucuronosyltransferases (UGTs) are a superfamily of enzymes that catalyze the conjugation of glucuronic acid to molecules primarily to facilitate systemic elimination (Radominska-Pandya et al., 1999).

What is the difference between Crigler-Najjar and Gilbert?

Symptoms of this disorder (if any) may result from reduced activity of the liver UGT1A1 enzyme. Gilbert syndrome is caused by mutations of the same gene that causes Crigler-Najjar syndrome, but affected individuals maintain about one third of the normal activity of the UGT1A1 enzyme.

What are UGT enzymes?

UDP-glucuronosyltransferase (UGT) enzymes catalyze the attachment of a glucuronic acid moiety to various drugs and other xenobiotics, as well as to endogenous compounds such as bilirubin. This conjugation promotes their excretion.

What is conjugated and unconjugated bilirubin?

Some bilirubin is bound to a certain protein (albumin) in the blood. This type of bilirubin is called unconjugated, or indirect, bilirubin. In the liver, bilirubin is changed into a form that your body can get rid of. This is called conjugated bilirubin or direct bilirubin.

Why bilirubin is conjugated with glucuronic acid?

Once in the liver, glucuronic acid is added to unconjugated bilirubin by the enzyme glucuronyl transferase. This forms conjugated bilirubin, which is soluble. This allows conjugated bilirubin to be excreted into the duodenum in bile.

What is UDP glycosyltransferase?

UDP-glycosyltransferases (UGTs) are important conjugation enzymes found in all kingdoms of life, catalyzing a sugar conjugation with small lipophilic compounds and playing a crucial role in detoxification and homeostasis.

What is Crigler Najjar type 1?

Crigler Najjar syndrome, type 1 is an inherited disorder in which bilirubin, a substance made by the liver, cannot be broken down. This condition occurs when the enzyme that normally converts bilirubin into a form that can easily be removed from the body does not work correctly.

What is the difference between Crigler-Najjar syndrome type 1 and type 2?

Crigler-Najjar syndrome is divided into two types. Type 1 (CN1) is very severe, and affected individuals can die in childhood due to kernicterus, although with proper treatment, they may survive longer. Type 2 (CN2) is less severe.

What enzyme catalyzes the conjugation of bilirubin?

Conjugation of bilirubin is catalyzed by bilirubin uridine diphosphate-glucuronosyltransferase (UDPGT-1),29 one of a family of enzymes that catalyze the hepatic glucuronidation of a number of endogenously produced or exogenously introduced small molecules, such as bilirubin, barbiturates, and phenols.

Where are UGT enzymes found?

This enzyme converts the toxic form of bilirubin (unconjugated bilirubin) to its nontoxic form (conjugated bilirubin), making it able to be dissolved and removed from the body. The bilirubin-UGT enzyme is primarily found in cells of the liver, where bilirubin glucuronidation takes place.

What is the function of uridine diphosphate glucuronosyltransferase?

The uridine diphosphate glucuronosyltransferase (UGT) superfamily of endoplasmic reticulum-bound enzymes is responsible for conjugating a glucuronic acid moiety to a variety of compounds, thus allowing these compounds to be more easily eliminated.

What type of reaction is UDP glucuronosyltransferase?

Uridine 5′-diphospho-glucuronosyltransferase (UDP-glucuronosyltransferase, UGT) is a microsomal glycosyltransferase (EC 2.4.1.17) that catalyzes the transfer of the glucuronic acid component of UDP-glucuronic acid to a small hydrophobic molecule. This is a glucuronidation reaction.

How is bilirubin made in the body?

Bilirubin is made in the body when red blood cells break down through a natural process.

What is the role of glucuronosyltransferases in Phase II metabolism?

Glucuronosyltransferases are responsible for the process of glucuronidation, a major part of phase II metabolism. Arguably the most important of the Phase II (conjugative) enzymes, UGTs have been the subject of increasing scientific inquiry since the mid-to-late 1990s. The reaction catalyzed by the UGT enzyme involves the addition…