The main function of trypanothione synthase is to use the free energy generated from ATP hydrolysis to conjugate glutathione and spermidine to form the intermediate of glutathionylspermidine and then the final product of trypanothione.
It also catalyzes the reverse reaction as well, albeit at a much lower rate.
Under conditions found to be the optimum for both the forward and backwards reactions, trypanothione synthase from trypanosoma cruzi was found to have an amidase activity that was only about 1% of the forwards synthetase activity.
 This low activity can be explained by the blocking of the catalytic Cys in the amidase active site in order for the protein to properly fold.

In parasitic kinetoplastids trypanothione synthase activity is key to survival.
 Due to the need for trypanothione in order to defend against oxidative stresses, and maintain thiol and ribonucleotide metabolism.
It was observed that induced knockout of trypanothione synthase through RNA interference caused a reduced growth rate of twofold among trypanosoma brucei due to the immediate disruption of flux through thiol redox.
 In other similar experiments which observed cell death after knocking out trypanothione synthase, it was shown that after two hours of being exposed to hydrogen peroxide in order to mimic the oxidant attack of phagocytes, the cells which did not contain working trypanothione synthase had a much higher death rate than wild type T. brucei.
The main function of trypanothione synthase is to use the free energy generated from ATP hydrolysis to conjugate glutathione and spermidine to form the intermediate of glutathionylspermidine and then the final product of trypanothione. It also catalyzes the reverse reaction as well, albeit at a much lower rate. Under conditions found to be the optimum for both the forward and backwards reactions, trypanothione synthase from trypanosoma cruzi was found to have an amidase activity that was only about 1% of the forwards synthetase activity.  This low activity can be explained by the blocking of the catalytic Cys in the amidase active site in order for the protein to properly fold.
In parasitic kinetoplastids trypanothione synthase activity is key to survival.  Due to the need for trypanothione in order to defend against oxidative stresses, and maintain thiol and ribonucleotide metabolism. It was observed that induced knockout of trypanothione synthase through RNA interference caused a reduced growth rate of twofold among trypanosoma brucei due to the immediate disruption of flux through thiol redox.  In other similar experiments which observed cell death after knocking out trypanothione synthase, it was shown that after two hours of being exposed to hydrogen peroxide in order to mimic the oxidant attack of phagocytes, the cells which did not contain working trypanothione synthase had a much higher death rate than wild type T. brucei.
Trypanothione synthase