3B63

Actin filament model in the extended form of acromsomal bundle in the Limulus sperm

ELECTRON MICROSCOPY

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Sample
Acrosomal bundle from Limulus sperm
Sample Components
An actin filament model in the acrosomal bundle refined from multiple actin crystal structures

Specimen Preparation
Sample Aggregation State	FILAMENT
Vitrification Instrument	HOMEMADE PLUNGER
Cryogen Name	ETHANE
Sample Vitrification Details

3D Reconstruction
Reconstruction Method	CRYSTALLOGRAPHY
Number of Particles
Reported Resolution (Å)	9.5
Resolution Method
Other Details	Cross-correlation and merging of crystallographic reflections derived from cryoelectron micrographs of 3D crystalss: application to the Limulus acrosomal bundle, Michael F. Schmid, J. Struc. Biol., 144 (2003) 195-208
Refinement Type
Symmetry Type	3D CRYSTAL

Map-Model Fitting and Refinement
Id	1 (1T44, 1HLU, 1ATN, 1YAG, 1YVN, 1MDU, 1HIV, 1NWK, 1ESV)
Refinement Space	REAL
Refinement Protocol	AB INITIO MODEL
Refinement Target	Best cross-correlation score between model and cryoEM map
Overall B Value
Fitting Procedure
Details	REFINEMENT PROTOCOL--Foldhunter program from EMAN single particle analysis package

Data Acquisition
Detector Type	KODAK SO-163 FILM
Electron Dose (electrons/Å**2)	15

Imaging Experiment	1
Date of Experiment
Temperature (Kelvin)	106
Microscope Model	JEOL 4000EX
Minimum Defocus (nm)	800
Maximum Defocus (nm)	3000
Minimum Tilt Angle (degrees)
Maximum Tilt Angle (degrees)
Nominal CS
Imaging Mode	BRIGHT FIELD
Specimen Holder Model
Nominal Magnification	40000
Calibrated Magnification
Source	LAB6
Acceleration Voltage (kV)	400
Imaging Details	For more information, please refer to EMDB entry EMD-1088 http://www.ebi.ac.uk/msd-srv/emsearch/atlas/1088_summary.html

EM Software
Task	Software Package	Version
MODEL FITTING	Foldhunter
RECONSTRUCTION	MRC