Table 1. Kinetic parameters for recombinant tritryp trypanothione synthetase (TryS).

Parasite	T. cruzi			T. b. brucei				L. major [26]	L. infantum [20]	C. fasciculate [23]
Strain	Silvio X10 clone 7 [25]	Tulahuen 0	Ninoa [22]	427 (MITat1.4) [27]			427a [24]	Friedlin	JPCM5	USb
KM GSHc	570 ± 50	140 ± 13	760 ± 210	56.2 ± 10.7d	23.8 ± 2.3e	142 ± 20	34 ± 4	89 ± 7	170 ± 23	1175
Ki GSH	1200 ± 100	1690 ± 172	Nof	36.5 ± 6.7d	55 ± 6e	254 ± 45	143 ± 20	1000 ± 80	699 ± 75	Yes
KM SPg	625 ± 39	702 ± 70	860 ± 95	37.8 ± 5.0d	45.4 ± 2.0e	238 ± 25	92 ± 25	940 ± 140	1434 ± 135	7424
KM ATP	53 ± 3	41 ± 6	70 ± 40	7.1 ± 0.4d	8.6 ± 0.6e	19 ± 5	6.6 ± 0.5	63 ± 2	43 ± 7	52
Ki ADP	NDh	60 ± 6	NDh	NDh	NDh	40 ± 5	NDh	NDh	90 ± 8	NDh

The apparent K_M and K_i values (μM) were determined using the lactate dehydrogenase (LDH)/pyruvate kinase (PK) assay and the K_i ADP was assessed using the end-point assay. Whenever available, the values are expressed as the mean ± S.D.. The parameters determined for the N-terminal His-tagged tritryp TryS studied in this work are shown in bold letters and the references to data published earlier in brackets. Please, refer to S8 Table for details about the conditions employed in the kinetic characterization of each enzyme.

^a Trypanosoma brucei brucei, strain 427, cell line 449.

^b US, unknown strain.

^c GSH, glutathione

^d Kinetic parameters determined for untagged Trypanosoma brucei TryS (TbTryS) using the PK/LDH coupled assay [27].

^e Kinetic parameters determined for untagged TbTryS using the end-point assay [18].

^f No, denotes lack of GSH inhibition at 4.5 mM.

^g SP, spermidine.

^h ND, not determined.