X-RAY DIFFRACTION Experimental Data & Validation


X-ray Experimental Help

Crystallization

Crystalization Experiments
pH 4.98
Details TRYPSIN-BENZAMIDINE, P3(1) 2 1 WERE GROWN BY VAPOR DIFFUSION, AS DESCRIBED FOR P2(1) 2(1) 2(1) (LARGE CELL) (MANGEL, ET AL., BIOCHEMISTRY 29, 8351-8357, 1990) THE CRYSTAL WAS SOAKED FOR 25 DAYS IN 2.11 M ZN+2, 250 MM CL-, PH 4.86 IN THE ABSENCE OF AN INHIBITOR. THIS SOLUTION WAS REPLACED ONCE EVERY DAY OR TWO TO REMOVE BOUND BENZAMIDINE AND TO INCORPORATE ZN+2 AT THE ACTIVE SITE. IT WAS THEN SOAKED IN CHLORIDE-FREE SOLUTION OF 1.02 MGSO4 . 7H2O, 1.62 M ZNSO4 . 7 H2O, 0.50 M ZINC ACETATE DIHYDRATE, PH 4.98 FOR 10 DAYS DURING WHICH THE SOAKING SOLUTION WAS REPLACED ONCE A DAY.

Crystal Data

Unit Cell
Length (Å) Angle (°)
a = 54.85 α = 90
b = 54.85 β = 90
c = 109.23 γ = 120
Symmetry
Space Group P 31 2 1

Diffraction

Diffraction Experiment
ID # Data Collection Temperature
1 298
Diffraction Detector
Detector Diffraction Type Details Collection Date
IMAGE PLATE RIGAKU RAXIS IV++ MSC MIRRORS 1998-04-05
Diffraction Radiation
Monochromator Protocol
-- SINGLE WAVELENGTH
Diffraction Detector Source
Source Type Wavelength List Synchrotron Site Beamline
ROTATING ANODE -- -- -- --

Data Collection

Overall
Resolution (High) Resolution (Low) Percent Possible (Observed) R Merge I (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
1.33 35.84 74.0 0.085 -- -- 2.3 -- 32374 -- 0.5 --
High Resolution Shell
Resolution (High) Resolution (Low) Percent Possible (All) R Merge I (Observed) R-Sym I (Observed) Mean I Over Sigma (Observed) Redundancy Number Unique Reflections (All)
1.4 1.46 37.4 0.345 -- 1.6 -- --

Refinement

Statistics
Structure Solution Method Refinement High Resolution Refinement Low Resolution Cut-off Sigma (I) Cut-off Sigma (F) Number of Reflections (All) Number of Reflections (Observed) Number of Reflections (R-Free) Percent Reflections (Observed) R-Factor (All) R-Factor (Observed) R-Work R-Free R-Free Selection Details
DIFFERENCE FOURIER PLUS REFINEMENT 1.4 7.5 -- 1.7 -- 28118 2864 74.0 -- 0.195 0.195 0.234 --
High Resolution Shell
Refinement method Shell Resolution (High) Shell Resolution (Low) # of Reflections (Observed) # of Reflections (R-Free) # of Reflections (R-Work) R-Factor (R-Work) R-Factor (R-Free) R-Factor (R-Free Error) Percent Reflections (Observed)
X Ray Diffraction 1.4 1.46 -- 178 1571 0.413 0.422 -- 37.4
RMS Deviations
Key Refinement Restraint Deviation
x_improper_angle_d 0.52
x_bond_d 0.018
x_angle_deg 3.7
x_dihedral_angle_d 26.2
Number of Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms Numbers
Protein Atoms 1629
Nucleic Acid Atoms 0
Heterogen Atoms 8
Solvent Atoms 213

Software

Computing
Computing Package Purpose
BIOTEX (MSC) Data Reduction (intensity integration)
BIOTEX Data Reduction (data scaling)
X-PLOR, QUANTA, INSIGHTII Structure Solution
X-PLOR 3.1 Structure Refinement
Software
Software Name Purpose
X-PLOR version: 3.1 refinement
INSIGHTII model building
QUANTA model building
X-PLOR model building
BIOTEX version: (MSC) data reduction
BIOTEX version: (MSC) data collection