Question

1. Describe the role of LDH in the catabolism of glucose.

2. Carbon monoxide is an inhibitor of Complex IV (cytochrome c oxidase). What is the effect of carbon monoxide on ATP and NADH levels? Explain your answer.

3. A new chemical has shown promising activity as an inhibitor of an enzyme from the malaria parasite. How would you determine whether it acted as a competitive or non-competitive inhibitor?

BIOCHEMISTRY QUESTIONS

Answer 1

1. LDH (lactate dehydrogenase) play very important role in anareboic respiration.

Anaerobic respiration is the process of conversion of pyruvate (formed in glycolysis) into lactate in the absence of oxygen.

For anaerobic respiration to occur , lactate dehydrogenase is required to convert NADH to NAD+.

This NAD+ is required in the glycolysis ie, breakdown or catabolism of glucose.

NAD+ is required when glyceraldehyde-3-phosphate dehydrogenase oxidizes glyceraldehyde-3-phosphate in glycolysis, which generates NADH.

NADH produces ATP which are the energy source of every cell.

So, LDH is required in the glycolysis ie, the catabolism of glucose into pyruvatepyruvate for ATP generation to take place in presence of oxygen.

In the absence of oxygen, it helps breakdown the pyruvate molecules into lactate in muscle cells.