2ABK

REFINEMENT OF THE NATIVE STRUCTURE OF ENDONUCLEASE III TO A RESOLUTION OF 1.85 ANGSTROM

X-RAY DIFFRACTION

---

Crystallization

Crystal Properties
Matthews coefficient	Solvent content
2.93	58.07

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 48.5	α = 90
b = 65.8	β = 90
c = 86.8	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		AREA DETECTOR	XENTRONICS		1993-05-18	M

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1			1.5418

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	1.85	20	99.8	0.07		10		27787

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-Factor (Observed)	R-Work	R-Free	Mean Isotropic B
X-RAY DIFFRACTION		1.85	10	2	26043		93.1	0.185	0.185	0.216	23.7

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_dihedral_angle_d	21
x_angle_deg	2.8
x_improper_angle_d	1.16
x_bond_d	0.015
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	1667
Nucleic Acid Atoms
Solvent Atoms	123
Heterogen Atoms	8

Software

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