2OXV

Structure of the A138T promiscuous mutant of the EcoRI restriction endonuclease bound to its cognate recognition site.

X-RAY DIFFRACTION

Starting Model(s)

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

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION, SITTING DROP	6.5	277.15	cryoprotectant solution is 40mM bis-tris Propane, 16% v/v PEG 400, 15% v/v glycerol, pH 6.5, VAPOR DIFFUSION, SITTING DROP, temperature 277.15K

Crystal Properties
Matthews coefficient	Solvent content
2.69	54.3

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 116.473	α = 90
b = 116.473	β = 90
c = 48.476	γ = 120

Symmetry
Space Group	P 3 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	100	CCD	ADSC QUANTUM 210	Si(111) channel cut monochromator. Toroidal focusing mirror	2003-11-18	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	NSLS BEAMLINE X6A	0.979	NSLS	X6A

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	1.95	99	99.9	0.077	25.1	17	27884	27856	2	2

Highest Resolution Shell
ID #	Resolution (High)	Resolution (Low)	Percent Possible (All)	Percent Possible (Observed)	R Merge I (Observed)	Mean I Over Sigma (Observed)	Redundancy	Number Unique Reflections (All)
	1.95	2.01	100		0.436	4.2	10.2	2283

Refinement

Statistics
Diffraction ID	Structure Solution Method	Cross Validation 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	R-Free	R-Free Selection Details	Mean Isotropic B
X-RAY DIFFRACTION	MOLECULAR REPLACEMENT	THROUGHOUT	1CKQ	1.95	12	2	27690	25266	2523	91.2	0.202	0.244	random	40.131

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]
-3.683	-4.593		-3.683		7.366

RMS Deviations
Key	Refinement Restraint Deviation
c_scangle_it	4.647
c_scbond_it	3.536
c_mcangle_it	3.442
c_mcbond_it	2.551
c_angle_d	1.324
c_bond_d	0.009

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	2053
Nucleic Acid Atoms	263
Solvent Atoms	136
Heterogen Atoms

Software

Software
Software Name	Purpose
DENZO	data reduction
SCALEPACK	data scaling
CNS	refinement
PDB_EXTRACT	data extraction
ADSC	data collection
HKL-2000	data reduction
CNS	phasing

RCSB PDB Core Operations are funded by the U.S. National Science Foundation (DBI-2321666), the US Department of Energy (DE-SC0019749), and the National Cancer Institute, National Institute of Allergy and Infectious Diseases, and National Institute of General Medical Sciences of the National Institutes of Health under grant R01GM157729.