Question

Propose an experiment to demonstrate that malonate is a competitive

inhibitor of Succinate DeHydrogenase rather than a non-competitive inhibitor.

Answer 1

You should design set up for this in following way:

You should have phosphate buffer, succinate dehydrogenase enzyme and malonate in equal amount and all favourable concentration in 10 set of test tube.

Now marks from 1 to 10 test tube and add succinate in the test tube in increasing concentration of substrate (succinate) from 20mM , 30 mM, 40 mM, 50mM, 60mM , 70mM, 80mM, 90mM, 100mM, 110mM. ( any of your choice )

Now take the absorbance value in spectrophotometer which will tells about enzyme activity.

You will find that in case of competitive inhibition, there will be less enzymatic activity in less amount of substrate. But you will find that with increase in concentration of substrate (succinate), the rate of enzyme activity is increased. This shows competitive inhibition.

If this trend do not follow, this will depict non competitive inhibition.