6HGN

Crystal structure of Alpha1-antichymotrypsin variant DBS-II-allo-L55V: an allosterically controlled doxorubicin-binding serpin with an unprecedentedly high ligand release efficacy

X-RAY DIFFRACTION

Starting Model(s)

Initial Refinement Model(s)
Type	Source	Accession Code	Details
experimental model	PDB	5OM7

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION, SITTING DROP		293	2 % Tacsimate pH 4.0, 0.1 M Sodium acetate trihydrate pH 4.6, 16 % w/v PEG 3,350

Crystal Properties
Matthews coefficient	Solvent content
2.16	43.04

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 84.832	α = 90
b = 84.832	β = 90
c = 97.066	γ = 120

Symmetry
Space Group	P 31 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	PIXEL	DECTRIS PILATUS 6M		2018-07-14	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	BESSY BEAMLINE 14.1	0.9184	BESSY	14.1

Data Collection

Overall
ID #	Resolution (High)	Resolution (Low)	Percent Possible (Observed)	Rrim I (All)	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	1.478	42.416	99.8	0.069	0.999	18.5	13.1		67808

Highest Resolution Shell
ID #	Resolution (High)	Resolution (Low)	Percent Possible (All)	Percent Possible (Observed)	Rrim I (All)	CC (Half)	Mean I Over Sigma (Observed)	Redundancy	Number Unique Reflections (All)
1	1.478	1.57			1.168	0.864	1.92

Refinement

Statistics
Diffraction ID	Structure Solution Method	Cross Validation 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	FREE R-VALUE	5OM7	1.478	42.416	1.37	67851	2100	99.84	0.1797	0.1791	0.1988

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	21.536
f_angle_d	1.073
f_chiral_restr	0.076
f_bond_d	0.009
f_plane_restr	0.006

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	2918
Nucleic Acid Atoms
Solvent Atoms	260
Heterogen Atoms	16

Software

Software
Software Name	Purpose
PHENIX	refinement
XDS	data reduction
XSCALE	data scaling
PHASER	phasing

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 R01GM157729.