4LX6

X-ray crystal structure of the M6C" riboswitch aptamer bound to 2-aminopyrimido[4,5-d]pyrimidin-4(3H)-one (PPAO)

X-RAY DIFFRACTION

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION, SITTING DROP	9	277	3M 1,6-hexanediol, 0.1 M tris ph9.0, 0.2 M MgCl2, VAPOR DIFFUSION, SITTING DROP, temperature 277K

Crystal Properties
Matthews coefficient	Solvent content
2.07	40.71

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 50.1	α = 90
b = 151.69	β = 90
c = 24.77	γ = 90

Symmetry
Space Group	P 21 21 2

Diffraction

Diffraction Experiment
ID #	Crystal ID	Scattering Type	Data Collection Temperature	Detector	Detector Type	Details	Collection Date	Monochromator	Protocol
1	1	x-ray	200	CCD	ADSC QUANTUM 315		2012-07-14	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	DIAMOND BEAMLINE I02	1.0	Diamond	I02

Data Collection

Overall
ID #	Resolution (High)	Resolution (Low)	Percent Possible (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	2.15	47.5	99.3			10992	10915	2.15	2.15

Refinement

Statistics
Diffraction ID	Structure Solution Method	Starting model	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	MOLECULAR REPLACEMENT	PDB ENTRY 3LA5	2.15	47.5	1.34	10894	523	99.33	0.2064	0.2038	0.2548	57.4802

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	12.416
f_angle_d	0.91
f_chiral_restr	0.038
f_plane_restr	0.007
f_bond_d	0.005

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms
Nucleic Acid Atoms	1502
Solvent Atoms	22
Heterogen Atoms	17

Software

Software
Software Name	Purpose
PHENIX	refinement
PDB_EXTRACT	data extraction
XDS	data scaling
XDS	data reduction
PHASER	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.