1CLI

X-RAY CRYSTAL STRUCTURE OF AMINOIMIDAZOLE RIBONUCLEOTIDE SYNTHETASE (PURM), FROM THE E. COLI PURINE BIOSYNTHETIC PATHWAY, AT 2.5 A RESOLUTION

X-RAY DIFFRACTION

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Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1		5.6		pH 5.6

Crystal Properties
Matthews coefficient	Solvent content
2.4	47.5

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 71.17	α = 90
b = 211.68	β = 90
c = 94.45	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	170	CCD	ADSC	MIRRORS	1998-02-19	M	MAD

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	CHESS BEAMLINE F2	0.9792,0.9790,0.9638	CHESS	F2

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	20	91.4	4.7	8.8	4.2		44742		2	35.7

Highest Resolution Shell
ID #	Resolution (High)	Resolution (Low)	Percent Possible (All)	Percent Possible (Observed)	R-Sym I (Observed)	Mean I Over Sigma (Observed)	Redundancy	Number Unique Reflections (All)
1	2.5	2.64	93		14.3	5.1	4.1

Refinement

Statistics
Diffraction ID	Structure Solution Method	Cross Validation method	Resolution (High)	Resolution (Low)	Cut-off Sigma (F)	Number Reflections (Observed)	Number Reflections (R-Free)	Percent Reflections (Observed)	R-Work	R-Free	R-Free Selection Details	Mean Isotropic B
X-RAY DIFFRACTION	MAD	THROUGHOUT	2.5	20	2	43410	2610	86.6	0.192	0.264	RANDOM	16.6

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	25
x_scangle_it	1.58
x_angle_deg	1.4
x_improper_angle_d	1.25
x_mcangle_it	1.19
x_scbond_it	0.97
x_mcbond_it	0.68
x_bond_d	0.009
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

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	9990
Nucleic Acid Atoms
Solvent Atoms	503
Heterogen Atoms	20

Software

Software
Software Name	Purpose
SnB	phasing
X-PLOR	refinement
MOSFLM	data reduction
CCP4	data scaling