3RSK

STRUCTURE OF THE K7A/R10A/K66A VARIANT OF RIBONUCLEASE A

X-RAY DIFFRACTION

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION, HANGING DROP	4.5		CRYSTALS WERE PREPARED USING THE HANGING DROP METHOD. LYOPHILIZED K7A/R10A/K66A RNASE A WAS DISSOLVED IN UNBUFFERED WATER TO A CONCENTRATION OF 60MG/ML. DROPS CONSISTING OF PROTEIN SOLUTION (1.5UL), WATER (1.5UL), AND RESERVOIR SOLUTION (3.0UL) WERE SUSPENDED OVER 0.5 ML OF RESERVOIR SOLUTION [0.1M SODIUM ACETATE BUFFER, PH 4.5, CONTAINING 36% PEG 4000., vapor diffusion - hanging drop

Crystal Properties
Matthews coefficient	Solvent content
3.25	60

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 68.15	α = 90
b = 68.15	β = 90
c = 65.51	γ = 120

Symmetry
Space Group	P 32 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	273	AREA DETECTOR	SIEMENS	LONG MIRRORS	1997-09-11	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 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	30	91	0.023	20	2.3		33804		0.33

Highest Resolution Shell
ID #	Resolution (High)	Resolution (Low)	Percent Possible (All)	Percent Possible (Observed)	R-Sym I (Observed)	Mean I Over Sigma (Observed)	Redundancy	Number Unique Reflections (All)
	2	2.1	84		0.17

Refinement

Statistics
Diffraction ID	Structure Solution Method	Starting model	Resolution (High)	Resolution (Low)	Number Reflections (All)	Number Reflections (Observed)	Number Reflections (R-Free)	Percent Reflections (Observed)	R-Factor (All)	R-Work	R-Free	Mean Isotropic B
X-RAY DIFFRACTION	MOLECULAR REPLACEMENT	PDB ENTRY 1RPH	2	30	14929	14929		91	0.174

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
t_dihedral_angle_d	17.868
t_angle_deg	2.236
t_it	1
t_nbd	0.027
t_bond_d	0.01
t_gen_planes	0.01
t_trig_c_planes	0.005
t_incorr_chiral_ct
t_pseud_angle

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	937
Nucleic Acid Atoms
Solvent Atoms	82
Heterogen Atoms	4

Software

Software
Software Name	Purpose
XDS	data scaling
XCALIBRE	data reduction
AMoRE	phasing
TNT	refinement
XDS	data reduction
XCALIBRE	data scaling

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.