Question

In the citric acid cycle, what metabolites serve as starting points for the metabolic pathways of fats and proteins?

Propose a new cancer drug and biochemical target based on the regulation of hypoxia in cancer cells (short description).

Answer 1

starting points forthe metabolic pathways of fats and proteins in Acetyl CoA the citric acid cycle serves as In the citric acid cycle, all the aerobic organism harvest stored energy from the food in a series of chemical reactions through the oxidation of acetyl CoA which is derived from carbohydrates, fats and proteins and transformed into adenosine triphosphate (ATP) and carbon dioxide. In the first step, the glycolysis occurs where the simple sugar molecules broke down to produce pyruvate, which further transformed in to acetyl CoA in the mitochondria. In the citric acid cycle, these acetyl CoA is modified to produce energy precursors in a step-by-step process. Hypoxia in cancer cells defined as the situation where cancer (tumor) cells have been deprived of oxygen in comparison to the normal cells. The blood supply of the tumor cells rapidly increases with increases in the tumor, leaving with significantly lower oxygen concentration than in healthy tissue cells. This situation in the cancer cells is called hypoxia. The development of specifically designed bioreductive prodrugs such as Tirapazamine (TPZ) plays a significant role to target these kinds of hypoxic tumor cells. Tirapazamine (TPZ) selectively attacks and kills the oxygen-deficient tumor cells through bioreductive mechanisms in which the selective toxicity towards the hypoxic cancer cells through an enzymatic one-electron reduction to the TPZ radical. Whereas in case of normal cells with availability of sufficient oxygen, this species reacts with oxygen to give back TPZ molecules, together with a superoxide radical portions of the tumor some