1EQZ

X-RAY STRUCTURE OF THE NUCLEOSOME CORE PARTICLE AT 2.5 A RESOLUTION

X-RAY DIFFRACTION

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Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION, HANGING DROP	6		pH 6.0, VAPOR DIFFUSION, HANGING DROP

Crystal Properties
Matthews coefficient	Solvent content
2.62	53.06

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 105.28	α = 90
b = 109.71	β = 90
c = 181.12	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	MARRESEARCH		1996-04-18	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	NSLS BEAMLINE X12C		NSLS	X12C

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	2.5	25.4	98.7	0.053		8.3	73319	73319			42.7

Refinement

Statistics
Diffraction ID	Structure Solution Method	Cross Validation method	Starting model	Resolution (High)	Resolution (Low)	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	SIR, MR	THROUGHOUT	2HIO, 1AOI	2.5	25.34	72200	72200	7303	98.6	0.219	0.219	0.282	RANDOM	53.2

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]
5.98			-5.53		-0.45

RMS Deviations
Key	Refinement Restraint Deviation
c_dihedral_angle_d	20.5
c_scangle_it	5.98
c_mcangle_it	4.96
c_scbond_it	4.68
c_mcbond_it	3.64
c_angle_deg	1.6
c_improper_angle_d	1.33
c_bond_d	0.013
c_bond_d_na
c_bond_d_prot
c_angle_d
c_angle_d_na
c_angle_d_prot
c_angle_deg_na
c_angle_deg_prot
c_dihedral_angle_d_na
c_dihedral_angle_d_prot
c_improper_angle_d_na
c_improper_angle_d_prot

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	6906
Nucleic Acid Atoms	5988
Solvent Atoms	349
Heterogen Atoms	29

Software

Software
Software Name	Purpose
SCALEPACK	data scaling
CCP4	model building
CNS	refinement
CCP4	phasing
CNS	phasing