Table 3.

Changes in thermal stabilization of DHPS imparted by the observed sulfonamide resistant variations.

	DHPS Variant	TM (°C)	Δ TM (°C)
Rosenbach 25923		38.63 ± 0.09
NCTC 8325		42.48 ± 0.01
Primary mutation	F17L	39.14 ± 0.0	0.51
	S18L	39.52 ± 0.003	0.89
	T51M	38.7 ± 0.09	0.07
Secondary mutation	E208K	34.89 ± 0.04	−3.74
	KE257_dup	34.26 ± 0.1	−4.37
Double mutation	F17L E208K	34.77 ± 0.05	−3.86
	F17L KE257_dup	40.34 ± 0.14	1.71
	T51M E208K	35.67 ± 0.05	−2.96

Changes in melting temperature (ΔT_M) are relative to the Rosenbach 25923 wild type DHPS enzyme.