Experiment: 1N4D

The Ligand-Free Structure of E coli BtuF, the Periplasmic Binding Protein for Vitamin B12

X-RAY DIFFRACTION

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION, HANGING DROP	4.6	294	acetate, PEG4000, (NH4)OAc, pH 4.6, VAPOR DIFFUSION, HANGING DROP, temperature 294K

Crystal Properties
Matthews coefficient	Solvent content
2.41	48.62

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 56.247	α = 90
b = 84.082	β = 90
c = 209.297	γ = 90

Symmetry
Space Group	C 2 2 21

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	BRANDEIS - B4		2002-10-15	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	NSLS BEAMLINE X12C	0.95	NSLS	X12C

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	20					12293			56.6

Refinement

Statistics
Diffraction ID	Structure Solution Method	Cross Validation method	Resolution (High)	Resolution (Low)	Cut-off Sigma (F)	Number Reflections (Observed)	Number Reflections (R-Free)	Percent Reflections (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	3	20	1	9684	484	12.7	0.242	0.2438	0.298	0.3134	RANDOM	63.3

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
x_dihedral_angle_d	24
x_improper_angle_d	1.38
x_angle_deg	1.3
x_bond_d	0.009

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	3663
Nucleic Acid Atoms
Solvent Atoms
Heterogen Atoms

Software

Software
Software Name	Purpose
DENZO	data reduction
SCALEPACK	data scaling
COMO	phasing
CNS	refinement