Experiment: 3F8G

The X-ray structure of a dimeric variant of human pancreatic ribonuclease with high cytotoxic and antitumor activities

X-RAY DIFFRACTION

Starting Model(s)

Initial Refinement Model(s)
Type	Source	Accession Code	Details
experimental model	PDB	1E21	PDB entry 1E21, the crystal structure of des(1-7)RNase

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION, SITTING DROP		277	A protein solution of 10mg/ml in 10mM Tris acteate ph 7.0, 300mM NaCl was equilibrated against a solution containing 27% w/v PEG, 0.2 M AS, and 100mM cacodylate buffer ph 6.5, VAPOR DIFFUSION, SITTING DROP, temperature 277K

Crystal Properties
Matthews coefficient	Solvent content
2.56	52.04

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 45.855	α = 90
b = 78.256	β = 90
c = 80.695	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	CCD	MAR CCD 165 mm	mirrors	2005-10-14	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	ELETTRA BEAMLINE 5.2R	1.00	ELETTRA	5.2R

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	2.6	40	98.7	0.09	20			9128

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 (Depositor)	R-Work (DCC)	R-Free (Depositor)	R-Free (DCC)	R-Free Selection Details	Mean Isotropic B
X-RAY DIFFRACTION	MOLECULAR REPLACEMENT	THROUGHOUT	PDB entry 1E21, the crystal structure of des(1-7)RNase	2.6	40	2	8980	8539	462	90.9	0.215	0.2213	0.306	0.3129	RANDOM

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]

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	1954
Nucleic Acid Atoms
Solvent Atoms	162
Heterogen Atoms	25

Software

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