1DC1

RESTRICTION ENZYME BSOBI/DNA COMPLEX STRUCTURE: ENCIRCLEMENT OF THE DNA AND HISTIDINE-CATALYZED HYDROLYSIS WITHIN A CANONICAL RESTRICTION ENZYME FOLD

X-RAY DIFFRACTION

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Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION, HANGING DROP	7.6	293	EQUILIBRATION AGAINST RESERVOIR OF 20% (V/V) DIOXANE, 2% (V/V) ETHYLENE GLYCOL AND 5 MM DTT. DROPS WERE FORMED BY MIXING 2.5 UL PROTEIN-DNA COMPLEX (10 MG/ML PROTEIN; 1.1 FOLD MOLAR EXCESS DNA) IN BUFFER (20 MM TRIS-HCL PH 7.6, 300 MM NACL, 0.1 MM EDTA, 1 MM DTT, 0.02% NA AZIDE) WITH 2.5 UL DISTILLED WATER, 2.5 UL RESERVOIR SOLUTION AND 1.5 UL 350 MM N-HEPTYL-B-D-GLUCOSIDE, VAPOR DIFFUSION, HANGING DROP, temperature 293.0K

Crystal Properties
Matthews coefficient	Solvent content
2.11	41.2

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 80.294	α = 90
b = 87.823	β = 90
c = 99.454	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	100	IMAGE PLATE	RIGAKU RAXIS		1998-09-01	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	ROTATING ANODE	RIGAKU RU200

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	1.7	30	99.4	0.059	24.5	3.7	77509	77509		-3	20.9

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)
	1.7	1.76	95.4		0.519	2.1	2.2

Refinement

Statistics
Diffraction ID	Structure Solution Method	Cross Validation method	Resolution (High)	Resolution (Low)	Cut-off Sigma (F)	Number Reflections (All)	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	MIR	THROUGHOUT	1.7	8	2	77509	75657	3845	99.4	0.19	0.19	0.253	RANDOM	23.33

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]
-0.73			-0.096		4.462

RMS Deviations
Key	Refinement Restraint Deviation
x_angle_deg	1.6
x_bond_d	0.01
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	4997
Nucleic Acid Atoms	490
Solvent Atoms	474
Heterogen Atoms	60

Software

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