3UA0

N-Terminal Domain of Bombyx mori Fibroin Mediates the Assembly of Silk in Response to pH Decrease

X-RAY DIFFRACTION

Crystallization

Crystalization Experiments
ID	Method	pH	Temperature	Details
1		4.6		1.2M (NH4)2SO4, 0.1M SODIUM ACETATE PH 4.6, VAPOR DIFFUSION, HANGING DROP, TEMPERATURE 289K

Crystal Properties
Matthews coefficient	Solvent content
2.76	55.37

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 74.52	α = 90
b = 74.52	β = 90
c = 208.23	γ = 120

Symmetry
Space Group	P 65 2 2

Diffraction

Diffraction Experiment
ID #	Crystal ID	Scattering Type	Data Collection Temperature	Detector	Detector Type	Details	Collection Date	Monochromator	Protocol
1	1	x-ray		CCD	RAYONIX MX225HE		2009-10-07	M	SINGLE WAVELENGTH

Radiation Source
ID #	Source	Type	Wavelength List	Synchrotron Site	Beamline
1	SYNCHROTRON	SSRF BEAMLINE BL17U		SSRF	BL17U

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	3	50	99.4	0.112	40.2	31.9		7427			101.75

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	3	3.05	94.5		0.654	3.3	19.1

Refinement

Statistics
Diffraction ID	Structure Solution Method	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	SAD	3	37.26	1.33	7294	333	98.4	0.312	0.311	0.336

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]
14.22			14.22		-28.44

RMS Deviations
Key	Refinement Restraint Deviation
f_dihedral_angle_d	20.536
f_angle_d	1.145
f_chiral_restr	0.077
f_bond_d	0.008
f_plane_restr	0.003

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	1165
Nucleic Acid Atoms
Solvent Atoms
Heterogen Atoms

Software

Software
Software Name	Purpose
SOLVE	phasing
PHENIX	refinement
HKL-2000	data reduction
HKL-2000	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 R01GM157729.