Table 1. Kinetics of P. falciparum TrpRSs.

protein	substrate	Kmapp (μM)	Vmaxapp(nmole/min)
TrpRScyt	ATP	622 ± 0.3	292 ± 0.01
	tryptophan	15.6 ± 0.6	77 ± 0.001
	tRNA
	*P. falciparum	0.020 ± 0.004	15 ± 0.01
	E. coli	1.2 ± 0.8	80 ± 0.1
	S. cerevisiae	0.23 ± 0.05	51 ± 0.02
TrpRSapi	tryptophan	5.3 ± 1.2	29 ± 0.001
	tRNA
	*P. falciparum	0.04 ± 0.02	1 ± 0.001
	E. coli	0.12 ± 0.03	15 ± 0.001
	S. cerevisiae	3.6 ± 1.3	2 ± 0.001

^*Total tRNA was used to determine kinetics of Pf  TrpRSs.