3ZRS

X-ray crystal structure of a KirBac potassium channel highlights a mechanism of channel opening at the bundle-crossing gate.

X-RAY DIFFRACTION

Starting Model(s)

Initial Refinement Model(s)
Type	Source	Accession Code	Details
experimental model	PDB	1X6C	PDB ENTRY 1X6C

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1				10% GLYCEROL, 90 MM HEPES 7.2, 20.0% PEG 400, 5% PEG 4K, 2.5% PEG 8K.

Crystal Properties
Matthews coefficient	Solvent content
4.02	69.43

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 106.24	α = 90
b = 106.24	β = 90
c = 89.8	γ = 90

Symmetry
Space Group	P 4 21 2

Diffraction

Diffraction Experiment
ID #	Crystal ID	Scattering Type	Data Collection Temperature	Detector	Detector Type	Details	Collection Date	Monochromator	Protocol
1	1	x-ray	100	PIXEL	DECTRIS PILATUS 6M		2011-02-12	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	DIAMOND BEAMLINE I24		Diamond	I24

Data Collection

Overall
ID #	Resolution (High)	Resolution (Low)	Percent Possible (Observed)	R Merge 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	3.05	106.24	99.9	0.13	5.5	6.8		10293		2	81.02

Highest Resolution Shell
ID #	Resolution (High)	Resolution (Low)	Percent Possible (All)	Percent Possible (Observed)	R Merge I (Observed)	Mean I Over Sigma (Observed)	Redundancy	Number Unique Reflections (All)
1	3.05	3.21	99.8		0.94	2	6.9

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 (Depositor)	R-Work (DCC)	R-Free (Depositor)	R-Free (DCC)	R-Free Selection Details	Mean Isotropic B
X-RAY DIFFRACTION	MOLECULAR REPLACEMENT	THROUGHOUT	PDB ENTRY 1X6C	3.05	89.8	2	10244	496	99.9	0.2222	0.2204	0.23	0.2589	0.27	RANDOM	54.39

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]
-10.0113			-10.0113		20.0227

RMS Deviations
Key	Refinement Restraint Deviation
t_other_torsion	3.33
t_omega_torsion	2.76
t_angle_deg	1.08
t_bond_d	0.01
t_dihedral_angle_d
t_incorr_chiral_ct
t_pseud_angle
t_trig_c_planes
t_gen_planes
t_it

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	2185
Nucleic Acid Atoms
Solvent Atoms	19
Heterogen Atoms	7

Software

Software
Software Name	Purpose
BUSTER	refinement
MOSFLM	data reduction
SCALA	data scaling
PHASER	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 R01GM157729.