2F1F

Crystal structure of the regulatory subunit of acetohydroxyacid synthase isozyme III from E. coli

X-RAY DIFFRACTION

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION	8.5	293	10-25 mg/ml protein in 0.5 M MgCl2, 1:1 mixed with reservoir made up of 30-40% PEG400, 0.4-0.6 M MgCl2, 100 mM Tris-HCl pH 8.5, VAPOR DIFFUSION, temperature 293K

Crystal Properties
Matthews coefficient	Solvent content
2.69	54.26

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 98.6	α = 90
b = 98.6	β = 90
c = 80	γ = 90

Symmetry
Space Group	I 4

Diffraction

Diffraction Experiment
ID #	Crystal ID	Scattering Type	Data Collection Temperature	Detector	Detector Type	Details	Collection Date	Monochromator	Protocol
1	1	x-ray	100	CCD	ADSC QUANTUM 4	bent crystal	2004-11-30	M	MAD
2	1	x-ray		M	SINGLE WAVELENGTH
3	1

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	ESRF BEAMLINE ID14-4	0.97924, 0.97942, 0.93928	ESRF	ID14-4

Data Collection

Overall
ID #	Resolution (High)	Resolution (Low)	Percent Possible (Observed)	R Merge I (Observed)	R Sym I (Observed)	Net I Over Average Sigma (I)	Redundancy	Number Reflections (All)	Number Reflections (Observed)	Observed Criterion Sigma (F)	Observed Criterion Sigma (I)	B (Isotropic) From Wilson Plot
1,2	1.75	40	99.2	0.063	0.057	15.1	6.15	38313	38313			38.2

Highest Resolution Shell
ID #	Resolution (High)	Resolution (Low)	Percent Possible (All)	Percent Possible (Observed)	R Merge I (Observed)	R-Sym I (Observed)	Mean I Over Sigma (Observed)	Redundancy	Number Unique Reflections (All)
	1.75	1.8	100		0.541	0.59	3.3	6.2	3076

Refinement

Statistics
Diffraction ID	Structure Solution Method	Cross Validation method	Resolution (High)	Resolution (Low)	Number Reflections (All)	Number Reflections (Observed)	Number Reflections (R-Free)	Percent Reflections (Observed)	R-Factor (All)	R-Factor (Observed)	R-Work	R-Free	R-Free Selection Details	Mean Isotropic B
X-RAY DIFFRACTION	MAD	THROUGHOUT	1.75	20	38313	38302	1917	99.26	0.174	0.174	0.171	0.227	RANDOM	41.821

Temperature Factor Modeling
Anisotropic B[1][1]	Anisotropic B[1][2]	Anisotropic B[1][3]	Anisotropic B[2][2]	Anisotropic B[2][3]	Anisotropic B[3][3]
-0.14			-0.14		0.27

RMS Deviations
Key	Refinement Restraint Deviation
r_dihedral_angle_2_deg	38.31
r_dihedral_angle_4_deg	22.608
r_dihedral_angle_3_deg	17.856
r_dihedral_angle_1_deg	8.516
r_scangle_it	7.705
r_scbond_it	5.557
r_mcangle_it	3.883
r_mcbond_it	2.6
r_angle_refined_deg	2.118
r_nbtor_refined	0.307

RMS Deviations
Key	Refinement Restraint Deviation
r_dihedral_angle_2_deg	38.31
r_dihedral_angle_4_deg	22.608
r_dihedral_angle_3_deg	17.856
r_dihedral_angle_1_deg	8.516
r_scangle_it	7.705
r_scbond_it	5.557
r_mcangle_it	3.883
r_mcbond_it	2.6
r_angle_refined_deg	2.118
r_nbtor_refined	0.307
r_nbd_refined	0.257
r_chiral_restr	0.243
r_symmetry_vdw_refined	0.227
r_symmetry_hbond_refined	0.222
r_xyhbond_nbd_refined	0.219
r_bond_refined_d	0.025
r_gen_planes_refined	0.008

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	2474
Nucleic Acid Atoms
Solvent Atoms	258
Heterogen Atoms	52

Software

Software
Software Name	Purpose
XSCALE	data scaling
SHARP	phasing
REFMAC	refinement
PDB_EXTRACT	data extraction

RCSB PDB Core Operations are funded by the National Science Foundation (DBI-1832184), the US Department of Energy (DE-SC0019749), and the National Cancer Institute, National Institute of Allergy and Infectious Diseases, and National Institute of General Medical Sciences of the National Institutes of Health under grant R01GM133198.