3ZD5

THE 2.2 A STRUCTURE OF A FULL-LENGTH CATALYTICALLY ACTIVE HAMMERHEAD RIBOZYME

X-RAY DIFFRACTION

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION, HANGING DROP		301	THE ENZYME AND SUBSTRATE WERE MIXED IN EQUIMOLAR AMOUNTS IN A SOLUTION CONTAINING 50 MM MES PH 5.5, 1.5 MM EDTA. THE COMPLEX WAS FORMED BY INCUBATING THE MIXTURE AT 95C FOR 2 MIN., THEN AT 65C FOR 2 MIN., AND FINALLY AT 27C FOR 5 MIN. 1 MM MGCL2 WAS INCLUDED IN THE MIXTURE BEFORE THE FINAL INCUBATION STEP. A 10 MG/ML CONCENTRATION OF RNA WAS USED FOR THE CRYSTALLIZATION EXPERIMENTS. THE RESERVOIR SOLUTION CONTAINED 0.5M (NH4)2SO4, 100 MM MES PH 6.5, AND 35% PEG 3350. AFTER MIXING THE RESERVOIR SOLUTION, THE SALT AND PEG PHASES WERE ALLOWED TO SEPARATE, AND ONLY THE SALT PHASE WAS USED FOR THE DROPS. THE CRYSTALS GREW IN HANGING DROPS OF 2 MICROLITERS AFTER 12 MONTHS OF INCUBATION AT 28C. THE CRYSTALS WERE WASHED IN THE SALT PHASE OF THE RESERVOIR SOLUTION PRIOR TO CRYO-FREEZING.

Crystal Properties
Matthews coefficient	Solvent content
2.36	47.78

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 49.886	α = 90
b = 69.21	β = 111.83
c = 60.076	γ = 90

Symmetry
Space Group	C 1 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	100	CCD	ADSC QUANTUM 315		2006-02-27	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	SSRL BEAMLINE BL9-1	0.919, 0.920, 0.9266	SSRL	BL9-1

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	2.2	55.73	99.2	0.04	16.9	4		9712			43.18

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	2.2	2.32	100		0.22	4.9	4.1

Refinement

Statistics
Diffraction ID	Structure Solution 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	MAD	2.2	20.22	1.5	9615	935	99.13	0.1805	0.1768	0.2117

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
f_dihedral_angle_d	15.306
f_angle_d	0.937
f_chiral_restr	0.039
f_plane_restr	0.006
f_bond_d	0.005

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms
Nucleic Acid Atoms	1346
Solvent Atoms	34
Heterogen Atoms

Software

Software
Software Name	Purpose
PHENIX	refinement
ADSC	data reduction
MOSFLM	data scaling
CNS	phasing

RCSB PDB Core Operations are funded by the National Science Foundation (DBI-1832184), 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 R01GM133198.