Experiment: 1HQ3

CRYSTAL STRUCTURE OF THE HISTONE-CORE-OCTAMER IN KCL/PHOSPHATE

X-RAY DIFFRACTION

Starting Model(s)

Initial Refinement Model(s)
Type	Source	Accession Code	Details
experimental model	PDB	1HIO	histone octamer PDB entry 1HIO

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	MICRODIALYSIS	6.7		2.0M KCL, 1.35M phosphate, pH 6.6, pH 6.7, MICRODIALYSIS

Crystal Properties
Matthews coefficient	Solvent content
3.45	64.4

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 158.56	α = 90
b = 158.56	β = 90
c = 102.48	γ = 120

Symmetry
Space Group	P 65

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	plane	1997-03-01	M	SINGLE WAVELENGTH
2	1	x-ray	100	CCD	MARRESEARCH	torroidal mirror	1998-09-01	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	SRS BEAMLINE PX7.2	1.488	SRS	PX7.2
2	SYNCHROTRON	SRS BEAMLINE PX9.5		SRS	PX9.5

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
1,2	2.15	20	97.4	0.071		2.26	74806	74806

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)
	2.15	2.25	97.1		0.331		2.16

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-Work (Depositor)	R-Work (DCC)	R-Free (Depositor)	R-Free Selection Details	Mean Isotropic B
X-RAY DIFFRACTION	MOLECULAR REPLACEMENT	THROUGHOUT	histone octamer PDB entry 1HIO	2.15	20	74806	74806	4451	97.4	0.2144	0.2121	0.2532	Random	40.8

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
c_dihedral_angle_d	20.3
c_scangle_it	5.7
c_scbond_it	4.02
c_mcangle_it	3.63
c_mcbond_it	2.39
c_angle_deg	1.6
c_improper_angle_d	1
c_bond_d	0.011

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	5985
Nucleic Acid Atoms
Solvent Atoms	437
Heterogen Atoms	47

Software

Software
Software Name	Purpose
DENZO	data reduction
SCALEPACK	data scaling
AMoRE	phasing
CNS	refinement