9MDD | pdb_00009mdd

Crystal Structure of human cyclic GMP-AMP synthase (cGAS) in complex with compound 23; (S)-1-(6,7-dichloro-1-methyl-1,3,4,5-tetrahydro-2H-pyrido[4,3-b]indol-2-yl)-2-methoxyethan-1-one

X-RAY DIFFRACTION

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Starting Model(s)

Initial Refinement Model(s)
Type	Source	Accession Code	Details
experimental model	PDB	9C8T

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION, SITTING DROP	8.5	289	(5mg/ml) HcGAS catalytic domain was mixed with 17/16 bp dsDNA in a molar ratio of 1:1.25 protein:DNA in a buffer containing 20 mM Tris pH 7.5, 150 mM NaCl, 10mM MnCl2, 1mM TCEP, 5mM AMPPNP and 1mM compound. Crystals were obtained with sitting drop vapor diffusion in drops mixed 1:1 with a reservoir of 0.1M Tris pH 8.0, 0.1 M Lithium Sulfate, 20% PEG 4000 and cGAS crystal seeds. Crystals were cryo-protected using reservoir solution supplemented with 25% ethylene glycol and flash-frozen in Liquid N2.

Crystal Properties
Matthews coefficient	Solvent content
2.42	49.2

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 128.3	α = 90
b = 51.71	β = 90
c = 60.09	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	100	PIXEL	DECTRIS EIGER X 9M		2021-10-23	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	NSLS-II BEAMLINE 17-ID-1	0.920105	NSLS-II	17-ID-1

Data Collection

Overall
ID #	Resolution (High)	Resolution (Low)	Percent Possible (Observed)	R Merge I (Observed)	CC (Half)	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	1.25	47.53	99.45	0.08475	0.998	9.44	7.4		73069			17.4

Highest Resolution Shell
ID #	Resolution (High)	Resolution (Low)	Percent Possible (All)	Percent Possible (Observed)	R Merge I (Observed)	Rrim I (All)	Rpim I (All)	CC (Half)	Mean I Over Sigma (Observed)	Redundancy	Number Unique Reflections (All)
1	1.25	1.295			0.08475	0.09122	0.03329	0.998

Refinement

Statistics
Diffraction ID	Structure Solution Method	Cross Validation method	Resolution (High)	Resolution (Low)	Cut-off Sigma (F)	Number Reflections (Observed)	Number Reflections (R-Free)	Percent Reflections (Observed)	R-Factor (Observed)	R-Work (Depositor)	R-Work (DCC)	R-Free (Depositor)	R-Free (DCC)	Mean Isotropic B
X-RAY DIFFRACTION	MOLECULAR REPLACEMENT	FREE R-VALUE	1.6	37.49	1.34	53565	2719	99.89	0.1953	0.194	0.1931	0.2202	0.2178	24.97

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	14.7068
f_angle_d	0.9679
f_chiral_restr	0.0562
f_plane_restr	0.0094
f_bond_d	0.0075

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	2909
Nucleic Acid Atoms
Solvent Atoms	160
Heterogen Atoms	64

Software

Software
Software Name	Purpose
PHENIX	refinement
DIALS	data reduction
Aimless	data scaling
PHASER	phasing