Isoleucine Deamination and Oxidation

The video tutorial explains the catabolic pathway of isoleucine, a branched-chain amino acid. It covers the initial reactions involving transaminase and the alpha-ketoacid dehydrogenase complex, leading to the production of NADH. The process of beta oxidation is discussed, highlighting the generation of FADH2 and reduced ubiquinol. The catabolism of Propionyl CoA is detailed, including its conversion to succinyl CoA via vitamin B12-dependent reactions. The video concludes with a calculation of the energy yield from isoleucine catabolism.

What is the initial molecule formed in the catabolism of isoleucine?

• 2-methylbutanoyl-CoA

• 3-methyl-2-keto-pentanoate

• Acetyl-CoA

• Propionyl-CoA

What is the role of branched chain transaminase in isoleucine catabolism?

• Decarboxylation

• Transamination

• Hydration

• Oxidation

Which enzyme complex is responsible for the decarboxylation in isoleucine catabolism?

• Branched chain transaminase

• Alpha-ketoacid dehydrogenase complex

• Beta-hydroxyacyl-CoA dehydrogenase

• Methylmalonyl-CoA mutase

During beta-oxidation, what is the first energy-yielding molecule produced?

• ATP

• Ubiquinol

• NADH

• FADH2

Which molecule is reduced to ubiquinol during the catabolism of isoleucine?

• ATP

• Coenzyme A

• NADH

• FADH2

What are the two products formed from 2-methylacetoacetyl-CoA?

• NADH and FADH2

• Acetyl-CoA and Propionyl-CoA

• Succinyl-CoA and Acetyl-CoA

• Propionyl-CoA and Succinyl-CoA

What is the significance of the TCA cycle in isoleucine catabolism?

• It generates propionyl-CoA.

• It is not involved in isoleucine catabolism.

• It produces energy in the form of ATP, NADH, and FADH2.

• It converts isoleucine directly to glucose.

Which vitamin is essential for the function of methylmalonyl-CoA mutase?

• Vitamin D

• Vitamin C

• Vitamin B12

• Vitamin B6

What is the final product of the methylmalonyl-CoA mutase reaction?

• Acetyl-CoA

• Propionyl-CoA

• 3-methyl-2-keto-pentanoate

• Succinyl-CoA

How many NADH molecules are generated from the complete catabolism of isoleucine?

• 3

• 5

• 6

• 8