8E13

Structures of HLA-B8E76C loaded with long peptides reveal novel features at the N-terminus of the groove

X-RAY DIFFRACTION

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION	5.6	298	0.2 M ammonium acetate, 18% PEG 4000, 0.1 M sodium citrate,

Crystal Properties
Matthews coefficient	Solvent content
2.54	51.49

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 50.577	α = 90
b = 81.273	β = 90
c = 110.498	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	103	CCD	MARMOSAIC 300 mm CCD		2020-08-09	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	APS BEAMLINE 21-ID-G	0.97872	APS	21-ID-G

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	1.37	65.47	99.5	0.068	29.1	4.2		95762

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	1.37	1.42	97		0.48		3.5

Refinement

Statistics
Diffraction ID	Structure Solution Method	Cross Validation method	Starting model	Resolution (High)	Resolution (Low)	Number Reflections (Observed)	Number Reflections (R-Free)	Percent Reflections (Observed)	R-Factor (Observed)	R-Work	R-Free	R-Free Selection Details	Mean Isotropic B
X-RAY DIFFRACTION	MOLECULAR REPLACEMENT	THROUGHOUT	6P2S	1.37	27	90865	4895	99.42	0.1682	0.166	0.21	RANDOM	18.537

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]
-1.17			-1.12		2.29

RMS Deviations
Key	Refinement Restraint Deviation
r_dihedral_angle_2_deg	30.261
r_dihedral_angle_4_deg	18.968
r_sphericity_free	18.69
r_sphericity_bonded	16.655
r_dihedral_angle_3_deg	13.631
r_dihedral_angle_1_deg	6.663
r_rigid_bond_restr	4.515
r_angle_refined_deg	2.115
r_angle_other_deg	1.522
r_chiral_restr	0.11

RMS Deviations
Key	Refinement Restraint Deviation
r_dihedral_angle_2_deg	30.261
r_dihedral_angle_4_deg	18.968
r_sphericity_free	18.69
r_sphericity_bonded	16.655
r_dihedral_angle_3_deg	13.631
r_dihedral_angle_1_deg	6.663
r_rigid_bond_restr	4.515
r_angle_refined_deg	2.115
r_angle_other_deg	1.522
r_chiral_restr	0.11
r_bond_refined_d	0.017
r_gen_planes_refined	0.013
r_bond_other_d	0.001
r_gen_planes_other	0.001

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	3148
Nucleic Acid Atoms
Solvent Atoms	247
Heterogen Atoms

Software

Software
Software Name	Purpose
PHASER	phasing
REFMAC	refinement
PDB_EXTRACT	data extraction
XDS	data reduction
XDS	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 R01GM133198.