5O3T | pdb_00005o3t

Straight filament in Alzheimer's disease brain

ELECTRON MICROSCOPY

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Starting Model(s)

Initial Refinement Model(s)
Type	Source	Accession Code	Details
experimental model	PDB	2RNM

Sample
Tau

Specimen Preparation
Sample Aggregation State	TISSUE
Vitrification Instrument	FEI VITROBOT MARK IV
Cryogen Name	ETHANE
Sample Vitrification Details

3D Reconstruction
Reconstruction Method	HELICAL
Number of Particles	24689
Reported Resolution (Å)	3.4
Resolution Method	FSC 0.143 CUT-OFF
Other Details
Refinement Type
Symmetry Type	HELICAL
Axial Symmetry	C1
Axial Rise	4.74
Angular Rotation	-1.05

Map-Model Fitting and Refinement
Id	1 (2RNM)
Refinement Space	RECIPROCAL
Refinement Protocol	AB INITIO MODEL
Refinement Target	Fourier shell correlation
Overall B Value	114
Fitting Procedure
Details	Fourier-space refinement of the complete atomic model against the paired helical filament and straight filament maps was performed in REFMAC. A stack of three consecutive monomers from each of the protofilaments was refined to preserve nearest-neighbour interactions for the middle chain.

Data Acquisition
Detector Type	GATAN K2 QUANTUM (4k x 4k)
Electron Dose (electrons/Å**2)	1.2

Imaging Experiment	1
Date of Experiment
Temperature (Kelvin)
Microscope Model	FEI TITAN KRIOS
Minimum Defocus (nm)	900
Maximum Defocus (nm)	3000
Minimum Tilt Angle (degrees)
Maximum Tilt Angle (degrees)
Nominal CS	2.7
Imaging Mode	BRIGHT FIELD
Specimen Holder Model	FEI TITAN KRIOS AUTOGRID HOLDER
Nominal Magnification
Calibrated Magnification
Source	FIELD EMISSION GUN
Acceleration Voltage (kV)	300
Imaging Details

EM Software
Task	Software Package	Version
PARTICLE SELECTION	RELION	2.0
CTF CORRECTION	Gctf
MODEL FITTING	Coot
INITIAL EULER ASSIGNMENT	RELION	2.0
FINAL EULER ASSIGNMENT	RELION	2.0
CLASSIFICATION	RELION	2.0
RECONSTRUCTION	RELION	2.0
MODEL REFINEMENT	REFMAC

Image Processing
CTF Correction Type	CTF Correction Details	Number of Particles Selected	Particle Selection Details
PHASE FLIPPING AND AMPLITUDE CORRECTION		84701