Table 1. Comparison of K_m values for cAMP hydrolysis of T. brucei and T. cruzi PDEs.

The K_m values for cAMP hydrolysis of the T. cruzi PDEBs were measured, and compared with those of their T. brucei PDEB orthologues, published previously, as well as with the K_m of TbrPDEA. K_m values for cAMP hydrolysis were calculated using non-linear analysis with the Prism software. The K_m values for TbrPDEA, TbrPDEB1 and TbrPDEB2 are from previously published data, as is one of the TcrPDEB2 values.

	Km (μM)
Substrate	TbPDE1/TbrPDEA	TbPDE2B/TbrPDEB2	TbPDE2C/TbrPDEB1	TcrPDEB2	TcrPDEB1
cAMP	>600 [15]	2.4±0.6 [12]	8.0±2.3 [13]	5.8±0.6 7.3±0.9 [18]	11.2±0.2