1G6X

ULTRA HIGH RESOLUTION STRUCTURE OF BOVINE PANCREATIC TRYPSIN INHIBITOR (BPTI) MUTANT WITH ALTERED BINDING LOOP SEQUENCE

X-RAY DIFFRACTION

Starting Model(s)

Initial Refinement Model(s)
Type	Source	Accession Code	Details
experimental model	PDB	1QLQ

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION, HANGING DROP	7.5	292	2% PEG 400, 2 M AMMONIUM SULFATE, 0.1 M NA HEPES. A PROTEIN SAMPLE, LYOPHILIZED AFTER HPLC PURIFICATION FROM TFA/ACETONITRILE MIXTURE, WAS DISSOLVED IN WATER TO A CONCENTRATION OF 9 MG/2 UL DROPS OF THE PROTEIN SOLUTION WERE MIXED WITH 2 UL OF RESERVOIR SOLUTION CONTAINING 2% PEG 400, 2 M AMMONIUM SULFATE AND 0.1 M NA HEPES, PH 7.5. THE HANGING DROPLETS WERE EQUILIBRATED AT 19 DEG C THROUGH THE GAS PHASE WITH THE RESERVOIR. PRISMATIC CRYSTALS MEASURING UP TO 0.4 MM GREW WITHIN 12 HOURS. FOR LOW-TEMPERATURE DATA COLLECTION (100 K), THE CRYSTAL WAS CRYOPROTECTED IN THE RESERVOIR SOLUTION SUPPLEMENTED BY 30 % ETHYLENE GLYCOL., VAPOR DIFFUSION, HANGING DROP, temperature 292K

Crystal Properties
Matthews coefficient	Solvent content
2.28	46

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 51.891	α = 90
b = 51.891	β = 90
c = 43.035	γ = 90

Symmetry
Space Group	P 43 21 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		1999-07-07	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	EMBL/DESY, HAMBURG BEAMLINE X11		EMBL/DESY, HAMBURG	X11

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	0.86	20	94.9	0.036	54.1	17.3		47018		-3

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	0.86	0.9	88.6		0.488	3.61	6

Refinement

Statistics
Diffraction ID	Structure Solution Method	Cross Validation method	Starting model	Resolution (High)	Resolution (Low)	Number Reflections (All)	Number Reflections (R-Free)	Percent Reflections (Observed)	R-Factor (All)	R-Factor (Observed)	R-Work	R-Free	R-Free Selection Details	Mean Isotropic B
X-RAY DIFFRACTION	EXISTING MODEL	FREE R	1QLQ	0.86	10	46998	1883	94.9	0.1072	0.1068		0.14	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]

Coordinate Error
Structure Solution Method	Refinement High Resolution	Refinement Low Resolution
12	426	603

RMS Deviations
Key	Refinement Restraint Deviation
s_approx_iso_adps	0.094
s_non_zero_chiral_vol	0.083
s_anti_bump_dis_restr	0.081
s_zero_chiral_vol	0.06
s_angle_d	0.043
s_similar_adp_cmpnt	0.041
s_from_restr_planes	0.035
s_bond_d	0.023
s_rigid_bond_adp_cmpnt	0.007
s_similar_dist

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	452
Nucleic Acid Atoms
Solvent Atoms	170
Heterogen Atoms	44

Software

Software
Software Name	Purpose
DENZO	data reduction
SCALEPACK	data scaling
SHELX	model building
SHELXL-97	refinement
SHELX	phasing

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.