1LT3

HEAT-LABILE ENTEROTOXIN DOUBLE MUTANT N40C/G166C

X-RAY DIFFRACTION

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Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	3 layer capillary method	7.5		PROTEIN WAS CRYSTALLIZED FROM 5% PEG 6000, 100 MM NACL, 1 MM EDTA, 75 MM LACTOSE, 100 MM TRIS PH 7.5 USING THE 3 LAYER CAPPILARY METHOD, 3 layer capillary method

Crystal Properties
Matthews coefficient	Solvent content
2.23	44.94

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 119.7	α = 90
b = 101.1	β = 90
c = 64.2	γ = 90

Symmetry
Space Group	P 21 21 21

Diffraction

Diffraction Experiment
ID #	Crystal ID	Scattering Type	Data Collection Temperature	Detector	Detector Type	Details	Collection Date	Monochromator	Protocol
1	1	x-ray	295	IMAGE PLATE	RIGAKU RAXIS IV	MIRRORS	1996-09-19	M

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	ROTATING ANODE	RIGAKU RUH2R

Data Collection

Overall
ID #	Resolution (High)	Resolution (Low)	Percent Possible (Observed)	R Sym 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	2	100	90.5	0.053	17	2.9		48385		1

Highest Resolution Shell
ID #	Resolution (High)	Resolution (Low)	Percent Possible (All)	Percent Possible (Observed)	R-Sym I (Observed)	Mean I Over Sigma (Observed)	Redundancy	Number Unique Reflections (All)
	2	2.07	72		0.175	4.5

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	ISOMORPHOUS MOLECULAR REPLACEMENT	THROUGHOUT	PDB ENTRY 1LTT	2	10	2	48350	2424	90.6	0.188	0.188	0.261	RANDOM	25.9

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	23.1
x_angle_deg	1.9
x_improper_angle_d	1.5
x_bond_d	0.011
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_na
x_dihedral_angle_d_prot
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	5978
Nucleic Acid Atoms
Solvent Atoms
Heterogen Atoms	115

Software

Software
Software Name	Purpose
DENZO	data reduction
SCALEPACK	data scaling
X-PLOR	model building
X-PLOR	refinement
X-PLOR	phasing