Experiment: 1G96

X-RAY DIFFRACTION

Starting Model(s)

Initial Refinement Model(s)
Type	Source	Accession Code	Details
experimental model	PDB	1CEW	N-terminally truncated chicken cystatin (1cew.pdb) converted to a polyalanine chain and limited to those fragments that had been modeled in electron density (residues 86-90 not included)

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION, HANGING DROP	4.8	277	Lyophilized protein was dissolved in 100 mM sodium acetate buffer pH 4.8 containing 20 mM CaCl2. Droplets were equilibrated against 1 ml of reservoir with analogous buffer/CaCl2 solution. After 2 and 4 days, the reservoir solution was supplemented with 100 microliters of MPD, VAPOR DIFFUSION, HANGING DROP, temperature 277K

Crystal Properties
Matthews coefficient	Solvent content
4.3	71

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 140.53	α = 90
b = 140.53	β = 90
c = 140.53	γ = 90

Symmetry
Space Group	I 4 3 2

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		2000-09-30	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	EMBL/DESY, HAMBURG BEAMLINE BW7B	0.8423	EMBL/DESY, HAMBURG	BW7B

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	2.5	40	99.2	0.07	27.8	19.9	8429	8429			40.6

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	2.5	2.59	93.5		0.413	2.5	4.1

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 (All)	R-Factor (Observed)	R-Work (Depositor)	R-Work (DCC)	R-Free (Depositor)	R-Free Selection Details	Mean Isotropic B
X-RAY DIFFRACTION	MOLECULAR REPLACEMENT	free R	N-terminally truncated chicken cystatin (1cew.pdb) converted to a polyalanine chain and limited to those fragments that had been modeled in electron density (residues 86-90 not included)	2.5	20	8500	8429	815	99.2	0.216	0.216	0.22	0.21	0.249	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]

RMS Deviations
Key	Refinement Restraint Deviation
c_dihedral_angle_d	25.8
c_scangle_it	6.08
c_mcangle_it	4.03
c_scbond_it	3.9
c_mcbond_it	2.41
c_angle_deg	2
c_improper_angle_d	1.85
c_bond_d	0.015

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	871
Nucleic Acid Atoms
Solvent Atoms	22
Heterogen Atoms	7

Software

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

RCSB PDB Core Operations are funded by the U.S. National Science Foundation (DBI-2321666), the US Department of Energy (DE-SC0019749), and the National Cancer Institute, National Institute of Allergy and Infectious Diseases, and National Institute of General Medical Sciences of the National Institutes of Health under grant R01GM157729.