1C2M

RECRUITING ZINC TO MEDIATE POTENT, SPECIFIC INHIBITION OF SERINE PROTEASES

X-RAY DIFFRACTION

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Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1		4.98		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 Properties
Matthews coefficient	Solvent content
2.03	18

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 #	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++	MSC MIRRORS	1998-04-05	M	SINGLE WAVELENGTH

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

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	1.33	35.84	74	0.085	8.2	2.3		32374		0.5

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)
	1.4	1.46	37.4		0.345	1.6

Refinement

Statistics
Diffraction ID	Structure Solution Method	Cross Validation method	Resolution (High)	Resolution (Low)	Cut-off Sigma (F)	Number Reflections (Observed)	Number Reflections (R-Free)	Percent Reflections (Observed)	R-Factor (Observed)	R-Work	R-Free	Mean Isotropic B
X-RAY DIFFRACTION	DIFFERENCE FOURIER PLUS REFINEMENT	X-PLOR	1.4	7.5	1.7	28118	2864	74	0.195	0.195	0.234

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_dihedral_angle_d	26.2
x_angle_deg	3.7
x_improper_angle_d	0.52
x_bond_d	0.018
x_bond_d_na
x_bond_d_prot
x_angle_d
x_angle_d_na
x_angle_d_prot
x_angle_deg_na
x_angle_deg_prot
x_dihedral_angle_d_na
x_dihedral_angle_d_prot
x_improper_angle_d_na
x_improper_angle_d_prot
x_mcbond_it
x_mcangle_it
x_scbond_it
x_scangle_it

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	3297
Nucleic Acid Atoms
Solvent Atoms	639
Heterogen Atoms	8

Software

Software
Software Name	Purpose
bioteX	data collection
bioteX	data reduction
X-PLOR	model building
Quanta	model building
Insight II	model building
X-PLOR	refinement
bioteX	data scaling
X-PLOR	phasing