6NXZ

Crystal structure of trimethoprim-resistant type II dihydrofolate reductase in complex with a bisbenzimidazole inhibitor

Experimental procedure

Experimental method	SINGLE WAVELENGTH
Source type	ROTATING ANODE
Source details	RIGAKU MICROMAX-007 HF
Temperature [K]	93
Detector technology	CCD
Collection date	2014-09-30
Detector	RIGAKU SATURN 944+
Wavelength(s)	1.54
Spacegroup name	I 41 2 2
Unit cell lengths	67.617, 67.617, 51.977
Unit cell angles	90.00, 90.00, 90.00

Refinement procedure

Resolution	47.860 - 1.750
R-factor	0.1785
Rwork	0.177
R-free	0.20820
Structure solution method	MOLECULAR REPLACEMENT
Starting model (for MR)	2rh2
RMSD bond length	0.020
RMSD bond angle	2.061
Data reduction software	HKL-2000
Data scaling software	HKL-2000
Phasing software	REFMAC
Refinement software	REFMAC (5.8.0073)

Data quality characteristics

	Overall	Inner shell	Outer shell
Low resolution limit [Å]	50.000	50.000	1.780
High resolution limit [Å]	1.750	4.750	1.750
Rmerge	0.204	0.150
Rmeas	0.205	0.151
Rpim	0.020	0.014
Number of reflections	6007	366	153
<I/σ(I)>	4.6
Completeness [%]	94.3	99.2	48.7
Redundancy	79.2	116.5	1.5
CC(1/2)		0.999	0.697

Crystallization Conditions

crystal ID	method	pH	temperature	details
1	VAPOR DIFFUSION, HANGING DROP	8	277	The protein concentration was adjusted from 13.3 mg/ml to 10 mg/mL by addition of a final concentration of 25% MPD. Reservoirs were prepared in Eppendorf tubes with 100mM Tris-Cl pH 8.0 55% MPD in a Greiner 24-well hanging-drop crystallization plate. On a siliconized glass cover slip (Hampton Research), 2.0 uL of protein solution were combined with 2.0 uL of the reservoir solution. The plate was incubated at 277 K, and crystals were obtained after 3-4 days.