2QTO

An anisotropic model for potassium channel KcsA

X-RAY DIFFRACTION

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1		7.5		200 MM CACL2, 100 MM HEPES PH 7.5, 48% PEG 400

Crystal Properties
Matthews coefficient	Solvent content
4.99	75.34

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 128.78	α = 90
b = 68.93	β = 124.63
c = 112.04	γ = 90

Symmetry
Space Group	C 1 2 1

Diffraction

Diffraction Experiment
ID #	Crystal ID	Scattering Type	Data Collection Temperature	Detector	Detector Type	Details	Collection Date	Monochromator	Protocol
1	1	x-ray	100					M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	CHESS BEAMLINE A1	0.908	CHESS	A1

Data Collection

Overall
ID #	Resolution (High)	Resolution (Low)	Percent Possible (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	3.201	30	93.3		6.1		12603		2

Refinement

Statistics
Diffraction ID	Structure Solution Method	Cross Validation method	Starting model	Resolution (High)	Resolution (Low)	Cut-off Sigma (F)	Number Reflections (Observed)	Number Reflections (R-Free)	Percent Reflections (Observed)	R-Factor (Observed)	R-Work	R-Free	R-Free Selection Details	Mean Isotropic B
X-RAY DIFFRACTION	MIR	THROUGHOUT	1BL8	3.201	9.99	4	10912	1265	100	0.27164	0.27162	0.27181	RANDOM	121.433

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]
-1.06		-1.64	0.68		-1.49

RMS Deviations
Key	Refinement Restraint Deviation
r_dihedral_angle_2_deg	47.921
r_dihedral_angle_3_deg	20.4
r_dihedral_angle_4_deg	8.627
r_dihedral_angle_1_deg	5.493
r_angle_refined_deg	0.989
r_symmetry_vdw_refined	0.469
r_nbtor_refined	0.31
r_nbd_refined	0.285
r_xyhbond_nbd_refined	0.173
r_metal_ion_refined	0.108

RMS Deviations
Key	Refinement Restraint Deviation
r_dihedral_angle_2_deg	47.921
r_dihedral_angle_3_deg	20.4
r_dihedral_angle_4_deg	8.627
r_dihedral_angle_1_deg	5.493
r_angle_refined_deg	0.989
r_symmetry_vdw_refined	0.469
r_nbtor_refined	0.31
r_nbd_refined	0.285
r_xyhbond_nbd_refined	0.173
r_metal_ion_refined	0.108
r_chiral_restr	0.057
r_bond_refined_d	0.007
r_gen_planes_refined	0.003

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	2849
Nucleic Acid Atoms
Solvent Atoms	1
Heterogen Atoms	3

Software

Software
Software Name	Purpose
REFMAC	refinement
DENZO	data reduction
SCALEPACK	data scaling
SHELXS	phasing

RCSB PDB Core Operations are funded by the U.S. National Science Foundation (DBI-2321666), 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.