 Toxoplasma gondii is an obligate intracellular parasite that can cause both acute and chronic infections in humans and other mammals. Two distinct forms exist within the parasite, tachyzoids and bradyzoids, which are responsible for different stages of the disease cycle. Amylapectin, a carbohydrate polymer, is produced by the parasite and plays an important role in its growth and development. Knockout studies on two genes involved in amylapectin production and degradation, UDP sugar pyrophosphorylase, USP, and alpha-glucon water dikinase, GWD, revealed that they play critical roles in the parasite's ability to form tachyzoids and bradyzoids, as well as in the reactivation of chronic infections. These findings suggest that amylapectin metabolism is essential for optimal tachyzoid growth and bradyzoid formation and reactivation. This article was authored by Pu Chen, Song Song Yu, Yi Dan Wang, and others.