1P2I

Structural consequences of accommodation of four non-cognate amino-acid residues in the S1 pocket of bovine trypsin and chymotrypsin

X-RAY DIFFRACTION

Starting Model(s)

Initial Refinement Model(s)
Type	Source	Accession Code	Details
experimental model	PDB	3BTG	pdb entry 3btg

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION, HANGING DROP	7.5	310	50% ammonium sulfate, 0.1M Hepes, pH 7.5, VAPOR DIFFUSION, HANGING DROP, temperature 310K

Crystal Properties
Matthews coefficient	Solvent content
2.89	57.04

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 74.7	α = 90
b = 81	β = 90
c = 124.09	γ = 90

Symmetry
Space Group	I 2 2 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	mirrors	1998-04-04	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	ESRF BEAMLINE BM1A	0.8	ESRF	BM1A

Data Collection

Overall
ID #	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	1.65	24.41	99.8	0.062	0.062	9.7	4.3	45488	45488	2	2	17.53

Highest Resolution Shell
ID #	Resolution (High)	Resolution (Low)	Percent Possible (All)	Percent Possible (Observed)	R Merge I (Observed)	R-Sym I (Observed)	Mean I Over Sigma (Observed)	Redundancy	Number Unique Reflections (All)
	1.65	1.74	99.9		0.316	0.316	2.4	4.3	45489

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	R-Free	R-Free Selection Details	Mean Isotropic B
X-RAY DIFFRACTION	MOLECULAR REPLACEMENT	THROUGHOUT	pdb entry 3btg	1.65	24.41	45488	45488	2746	99.9	0.201	0.201	0.201	0.21	Random	20.29

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	25.26
c_angle_deg	1.33
c_improper_angle_d	0.73
c_bond_d	0.004

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	2084
Nucleic Acid Atoms
Solvent Atoms	228
Heterogen Atoms	11

Software

Software
Software Name	Purpose
DENZO	data reduction
SCALA	data scaling
CNS	refinement
CCP4	data scaling
CNS	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.