1GI3

A NOVEL SERINE PROTEASE INHIBITION MOTIF INVOLVING A MULTI-CENTERED SHORT HYDROGEN BONDING NETWORK AT THE ACTIVE SITE

X-RAY DIFFRACTION

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION	8.1	298	magnesium sulfate soak at pH 9.52. vapor diffusion at 298 K, pH 8.10

Crystal Properties
Matthews coefficient	Solvent content
2.99	58.83

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 63.9	α = 90
b = 62.27	β = 90
c = 70.08	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	298	IMAGE PLATE	RIGAKU RAXIS IV		2000-05-18	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	ROTATING ANODE	RIGAKU RU200

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	1.32	47.22	61.2	0.095	7.4	3	65870	40323		0.8

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)
	1.44	1.51	37.2		0.255			2334

Refinement

Statistics
Diffraction ID	Structure Solution Method	Resolution (High)	Resolution (Low)	Cut-off Sigma (F)	Number Reflections (All)	Number Reflections (Observed)	Number Reflections (R-Free)	Percent Reflections (Observed)	R-Factor (Observed)	R-Work	R-Free	Mean Isotropic B
X-RAY DIFFRACTION	FOURIER SYNTHESIS	1.44	7.5	1.8	51071	35750	3640	70	0.206	0.202	0.235

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_angle_deg	3.6
x_bond_d	0.018

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	3312
Nucleic Acid Atoms
Solvent Atoms	825
Heterogen Atoms	32

Software

Software
Software Name	Purpose
bioteX	data collection
bioteX	data reduction
X-PLOR	refinement
bioteX	data scaling

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.