Table 3.

Reaction rates of TMPKmt and TMPKec with various nucleoside triphosphates (NTP)

NTP	M. tuberculosis	E. coli
ATP	100	100
dATP	120	76
ITP	66	1
GTP	60	15
CTP	42	24
UTP	26	13

The reaction medium (0.5 mL final volume) was the same as described in Table 2. The concentrations of dTMP and nucleoside triphosphate were kept constant at 0.5 mM for TMPKmt and at 0.3 mM and 1 mM respectively for TMPKec. Activities with various NTPs are given considering the reaction rate with ATP as 100%.