Experiment: 3FB8

KcsA Potassium channel in the open-conductive state with 20 A opening at T112 in the presence of Rb+ ion

X-RAY DIFFRACTION

Starting Model(s)

Initial Refinement Model(s)
Type	Source	Accession Code	Details
experimental model	PDB	1K4C	PDB entry 1K4C

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION, SITTING DROP		298	20-25% PEG400, 50mM magnesium acetate, 50mM sodium acetate pH 5.0-6.0, VAPOR DIFFUSION, SITTING DROP, temperature 298K

Crystal Properties
Matthews coefficient	Solvent content
3.83	67.86

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 155.636	α = 90
b = 155.636	β = 90
c = 73.033	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		CCD	ADSC QUANTUM 315		2006-12-14	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	APS BEAMLINE 23-ID-D	1.0	APS	23-ID-D

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	3.4	40	90			12197	10972	2	2

Refinement

Statistics
Diffraction ID	Structure Solution Method	Starting model	Resolution (High)	Resolution (Low)	Cut-off Sigma (F)	Number Reflections (All)	Number Reflections (Observed)	Number Reflections (R-Free)	Percent Reflections (Observed)	R-Work (Depositor)	R-Work (DCC)	R-Free (Depositor)	Mean Isotropic B
X-RAY DIFFRACTION	MOLECULAR REPLACEMENT	PDB entry 1K4C	3.4	40	2	12197	10972	1128		0.2836	0.2858	0.3043

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]

RMS Deviations
Key	Refinement Restraint Deviation
c_angle_deg	1.44356
c_bond_d	0.019845

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	3907
Nucleic Acid Atoms
Solvent Atoms	4
Heterogen Atoms	4

Software

Software
Software Name	Purpose
ADSC	data collection
CNS	refinement
HKL-2000	data reduction
HKL-2000	data scaling
CNS	phasing