Table 1.

Kinetic parameters of the M. tuberculosis Dut and Dcd:dut enzymes.

Enzyme	kcat (s−1)	KM (μM)	Kd.dUPNPP (μM)	kcat/KM (M−1 s−1)	Efficiency
wt Dut	1.22 ± 0.06	1.7 ± 0.5	0.9 ± 0.5	7.18E + 05	1
S148A Dut	0.43 ± 0.04	1.5 ± 0.6	1.8 ± 1.0	2.87E + 05	0.4
T138stop Dut	0.0035 ± 0.0001	6.7 ± 0.4	3.9 ± 1.3	5.22E + 02	0.0007
D83N Dut	0.0013 ± 0.0005	7.7 ± 6.7*	1.5 ± 0.1	1.69E + 02*	0.0002
wt Dcd:dut dUTPase	0.033 ± 0.008	12 ± 3	—	2.75 E + 03	0.004
wt Dcd:dut dCTP deaminase	0.022 ± 0.005	20 ± 12		1.10 E + 03	NA
A115F Dcd:dut	no activity	—	—	—	—

*Data not reliable due to the limitations of the activity measurement.

NA: not applicable.