1CHQ

SURPRISING LEADS FOR A CHOLERA TOXIN RECEPTOR BINDING ANTAGONIST; CRYSTALLOGRAPHIC STUDIES OF CTB MUTANTS

X-RAY DIFFRACTION

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Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1		6.4		pH 6.4

Crystal Properties
Matthews coefficient	Solvent content
2.2	44.19

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 102.6	α = 90
b = 67.39	β = 131.63
c = 98.81	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		AREA DETECTOR	SIEMENS X1000		1994-11-01	M

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1

Data Collection

Refinement

Statistics
Diffraction ID	Structure Solution Method	Resolution (High)	Resolution (Low)	Cut-off Sigma (F)	Number Reflections (Observed)	Number Reflections (R-Free)	Percent Reflections (Observed)	R-Work	R-Free	Mean Isotropic B
X-RAY DIFFRACTION		2.1	12	3	22154		75.5	0.208		41.7

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_angle_deg	1.81
x_bond_d	0.014
x_bond_d_na
x_bond_d_prot
x_angle_d
x_angle_d_na
x_angle_d_prot
x_angle_deg_na
x_angle_deg_prot
x_dihedral_angle_d
x_dihedral_angle_d_na
x_dihedral_angle_d_prot
x_improper_angle_d
x_improper_angle_d_na
x_improper_angle_d_prot
x_mcbond_it
x_mcangle_it
x_scbond_it
x_scangle_it

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	4010
Nucleic Acid Atoms
Solvent Atoms	105
Heterogen Atoms

Software

Software
Software Name	Purpose
XENGEN	data collection
X-PLOR	model building
X-PLOR	refinement
XENGEN	data reduction
X-PLOR	phasing