Question

9.) 2,4-Dinitrophenol (2,4-DNP or simply DNP) is an organic compound with the formula HOC₆H₃(NO₂)_{2, and is} a proton ionophore that affects the membrane of the mitochondria. When an individual takes it, the person will lose weight and generate a lot of heat. Why is this? (DNP allows protons to move freely across the innner membrane of mitochondria).

Answer 1

9) Dinitrophenol produces its glycolytic effect through its effect on the muscle contraction process . Carbohydrate consumption markedly increases in the presence of dinitrophenol which allows for rapid weight loss when dinitrophenol is taken in small doses. Pyruvic acid is aerobically metabolised to H2O and CO2, but results in the production of lactic acid when metabolised anaerobically. The discrepancy between the stimulation of glycolysis and the inhibition of oxidative phosphorylation results in a rapid rise in the production of pyruvic acid, leading to an increased production of lactic acid

DNP acts as a protonophore, allowing protons to leak across the inner mitochondrial membrane and thus bypass ATP synthase. This makes ATP energy production less efficient. In effect, part of the energy that is normally produced from cellular respiration is wasted as heat