Question

Trypanosomes living in the bloodstream obtain all their free energy from glycolysis. They take up glucose from the host’s blood and excrete pyruvate as a waste product. In this part of their life-cycle, trypanosomes do not carry out any oxidative phosphorylation, but they do use another oxygen dependent pathway, which is absent in mammals, to oxidize NADH.

Why is this other pathway necessary?

Would the pathway be necessary if the trypanosomes excreted lactate rather than pyruvate?

Why would this pathway be a good target for antiparasitic drugs?

Answer 1

Ans) Glycerol Phosphate oxidase system is the important pathway using which the trypanosome is able to oxidize NADH and is an oxygen dependent pathway. It is able to oxidize the NADH and respiratory system

Ans) This pathway is necessary because the trypanosomes are not able to produce or excrete lactate but pyruvate. In absence of oxygen, lactate can be metabolized by fermentation and it helps in production of ATP molecules. This helps in providing energy and hence the reason why any other oxygen dependent process in not required,

Ans ) This pathway is good for anti-parasitic drugs as the drug is able to perform its function by reducing the respiratory channel for the trypanosome. There will be low rate of oxygen and hence the anti-parasitic drugs can inhibit the