1AET

VARIATION IN THE STRENGTH OF A CH TO O HYDROGEN BOND IN AN ARTIFICIAL PROTEIN CAVITY (1-METHYLIMIDAZOLE)

X-RAY DIFFRACTION

Starting Model(s)

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

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1		6		20% MPD, 40 MM PHOSPHATE PH 6.0. A SINGLE CRYSTAL OF W191G WAS SOAKED IN 50MM 1-METHYLIMIDAZOLE IN 40% MPD AND 60 MM PHOSPHATE AT PH 4.5.

Crystal Properties
Matthews coefficient	Solvent content
3.2	61

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 105.2	α = 90
b = 74.3	β = 90
c = 45.4	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	290	AREA DETECTOR	SIEMENS		1993-09-16	M

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	ROTATING ANODE	RIGAKU RUH2R

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	2.1	15	74	0.051	0.049	25.2	1.8		21369

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)
	1.89	2.01	35		0.23	0.52	1.9	1.4

Refinement

Statistics
Diffraction ID	Structure Solution Method	Starting model	Resolution (High)	Resolution (Low)	Number Reflections (Observed)	Number Reflections (R-Free)	Percent Reflections (Observed)	R-Work	R-Free	Mean Isotropic B
X-RAY DIFFRACTION	MOLECULAR REPLACEMENT	PDB ENTRY 1CMQ	2.1	7	19099		79

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]

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	2841
Nucleic Acid Atoms
Solvent Atoms	50
Heterogen Atoms	50

Software

Software
Software Name	Purpose
XTALVIEW	refinement
XENGEN	data reduction
XENGEN	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.