Toxoplasma gondii is an obligate intracellular parasite with the remarkable ability to infect any nucleated cell. The complex life cycle of the parasite takes place in a wide range of host niches with significant differentiation events. To adapt to these niches, the parasite is thought to rewire its metabolic capabilities, switching between biosynthesis and scavenge mechanisms. In this thesis, I will explore an integrated computational and experimental approach to understand the contributions of enzymes involved in the TCA cycle, fatty acid, vitamin B6 and heme metabolism, for the fast replicating tachyzoite stage. I describe the generation of harmonized stage-specific metabolic model, capable of predicting in silico essential genes, reactions, synthetic lethal pairs and a minimal media, along with experimental validation with CRISPR-Cas9 mediated genetics and metabolomics approaches. The importance of an essential TCA cycle enzyme, aconitase, and metabolic capabilities of a cyst-forming parasite, B. besnoiti was further interrogated and understood.