Hepatocellular carcinoma (HCC) is among theleading causes of cancer death worldwide. Studies of geneexpression in HCC cells demonstrated that the enzyme ornithineaminotransferase (OAT) is upregulated in these cells. Ornithine(structure to the right) is both an intermediate in the urea cycleas well as a precursor for the synthesis of the nonessentialamino acid proline. Unlike many aminotransferases, OAT actson the side chain amine of ornithine rather than the alpha-amino3.group.If OAT takes ornithine and alpha-ketoglutarate as(a)substrates, draw the structures of the products released aftercatalysis.(b)What cofactor does OAT use and how is it linked to the enzyme?Devise a strategy to alleviate HCC based on OAT and describe the specific steps required(c)to accomplish this. What is a major challenge in this approach? What pre-clinical effects would youwant to demonstrate before attempting to treat patients?

Aminotransferases are group of enzymes that catalyzes the transamination reaction between amino acid…

Answered: If OAT takes ornithine and…

Biochemistry

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ISBN:9781319114671

Author:Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.

Publisher:Lubert Stryer, Jeremy M. Berg, John L. Tymoczko, Gregory J. Gatto Jr.

Chapter1: Biochemistry: An Evolving Science

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Glucose-6-phosphatase deficiency (G6PD), also known as von Gierke disease, is glycogen storage disease. It is an autosomal recessive disease occurring most frequently in males of African or Middle Eastern descent. G6PD is involved in many reactions, but we will focus on the following simplified pathway: The conversion of glycogen to glucose is called:
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What does this important observation imply about the relation between the amino acid sequence of insulin and its three-dimensional structure?

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If OAT takes ornithine and alpha-ketoglutarate as (a) substrates, draw the structures of the products released after catalysis.