3J2O

Model of the bacteriophage T4 fibritin based on the cryo-EM reconstruction of the contracted T4 tail containing the phage collar and whiskers

ELECTRON MICROSCOPY

Sample
Bacteriophage T4 tail
Sample Components
fibritin

Specimen Preparation
Sample Aggregation State	PARTICLE
Vitrification Instrument	HOMEMADE PLUNGER
Cryogen Name	ETHANE
Sample Vitrification Details	plunged into liquid ethane (homemade plunger)

3D Reconstruction
Reconstruction Method	SINGLE PARTICLE
Number of Particles	2727
Reported Resolution (Å)	25
Resolution Method	FSC 0.5 CUT-OFF
Other Details
Refinement Type
Symmetry Type	POINT
Point Symmetry	C1

Map-Model Fitting and Refinement
Id	1
Refinement Space	REAL
Refinement Protocol
Refinement Target
Overall B Value
Fitting Procedure
Details	DETAILS--The model of fibritin comprises the crystal structure of the N-terminal domain (Boudko et al., 2004, J. Mol. Biol. 339, 927-935), the cryst ...	DETAILS--The model of fibritin comprises the crystal structure of the N-terminal domain (Boudko et al., 2004, J. Mol. Biol. 339, 927-935), the crystal structure of the C-terminal domain (Tao et al., 1997, Structure 5, 789-798), and the central region, modeled with segments of triple-helical coiled coil (Letarov et al., 2005, J. Bacteriol. 187, 1055-1066). These parts of the fibritin structure were fitted into the cryo-EM density using the program CHIMERA (Pettersen et al., 2004, J. Computat. Chem. 25, 1605-1612). Chains A, B, and C correspond to one fibritin molecule located in the phage collar. Chains D, E, and F correspond to one fibritin molecule forming the whisker.

Data Acquisition
Detector Type	KODAK SO-163 FILM
Electron Dose (electrons/Å**2)	16

Imaging Experiment	1
Date of Experiment	2007-03-07
Temperature (Kelvin)
Microscope Model	FEI/PHILIPS CM200FEG
Minimum Defocus (nm)	1500
Maximum Defocus (nm)	3000
Minimum Tilt Angle (degrees)
Maximum Tilt Angle (degrees)
Nominal CS	2
Imaging Mode	BRIGHT FIELD
Specimen Holder Model	GATAN LIQUID NITROGEN
Nominal Magnification	38000
Calibrated Magnification	39190
Source	FIELD EMISSION GUN
Acceleration Voltage (kV)	200
Imaging Details

EM Software
Task	Software Package	Version
MODEL FITTING	UCSF Chimera
RECONSTRUCTION	EMAN

Image Processing
CTF Correction Type	CTF Correction Details	Number of Particles Selected	Particle Selection Details
	phase flipping

RCSB PDB Core Operations are funded by the National Science Foundation (DBI-1832184), 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.