Experiment: 8X2W

Crystal structure of the ancestral GH19 chitinase, Anc4+LoopII (P12K/N13H/S58T/N193G/Y194F/D197R)

X-RAY DIFFRACTION

Starting Model(s)

Initial Refinement Model(s)
Type	Source	Accession Code	Details
in silico model	AlphaFold

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1	VAPOR DIFFUSION, SITTING DROP		293	1 uL of Anc4+Loop II+p12K/n13H/s58T/n193G/y194F/d197R (6.0 mg/mL in 10 mM sodium acetate pH 5.0, 150 mM NaCl) + 1 uL of 25% (w/v) polyethylene glycol 3,350, 0.1 M Bis-Tris, pH 6.5

Crystal Properties
Matthews coefficient	Solvent content
1.79	31.36

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 37.32	α = 90
b = 69.59	β = 90
c = 70.22	γ = 90

Symmetry
Space Group	P 2 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	100	PIXEL	DECTRIS EIGER X 16M		2023-07-29	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	SPRING-8 BEAMLINE BL32XU	1.000	SPring-8	BL32XU

Data Collection

Overall
ID #	Resolution (High)	Resolution (Low)	Percent Possible (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	1.4	49.43	100	0.992	7	52.2		46885			20.8

Highest Resolution Shell
ID #	Resolution (High)	Resolution (Low)	Percent Possible (All)	Percent Possible (Observed)	CC (Half)	Mean I Over Sigma (Observed)	Redundancy	Number Unique Reflections (All)
1	1.4	1.4	99.9		0.991

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	1.4	49.43	1.37	36817	2009	99.99	0.1874	0.1864	0.1865	0.2042	0.2036	23.56

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	5.6116
f_angle_d	1.0608
f_chiral_restr	0.0928
f_plane_restr	0.0109
f_bond_d	0.0091

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	1783
Nucleic Acid Atoms
Solvent Atoms	118
Heterogen Atoms

Software

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