1ML5

ELECTRON MICROSCOPY

Sample

release factor RF2 bound to E. coli ribosomes

Specimen Preperation
Sample Aggregation State PARTICLE
Vitrification Instrument HOMEMADE PLUNGER
Cryogen Name ETHANE
Sample Vitrification Details holey carbon grid at 20C; flash frozen into liquid ethan
3D Reconstruction
Reconstruction Method SINGLE PARTICLE
Number of Particles 15800
Reported Resolution (Å) 14
Resolution Method ?
Other Details iterative refinement procedure as described in Quat. Rev. of Biophysics 33, 4 (2000), pp. 307-369
Refinement Type
Symmetry Type POINT
Map-Model Fitting and Refinement
ID 1
Refinement Space REAL
Refinement Protocol RIGID BODY FIT
Refinement Target best visual fit using the program O
Overall B Value ?
Fitting Procedure ?
Details REFINEMENT PROTOCOL--rigid body fit of the 70S ribosome without individual fitting of proteins or RNA fragments. Rigid body fit of three individual domains of release factor RF2 keeping the connectivity; linkers betweenn domains defined based on temperature factors of crystal structure, conserved Gly and Pro residues, proteolytic sites, and global domain architecture
Data Acquisition
Detector Type KODAK SO-163 FILM
Electron Dose (electrons/Å2) 10
Imaging Experiment
Date of Experiment 2001-09-06
Temprature (Kelvin)
Microscope Model FEI/PHILIPS CM200FEG/ST
Minimum Defocus (nm) 500
Maximum Defocus (nm) 2900
Minimum Tilt Angle (degrees) 0
Maximum Tilt Angle (degrees) 0
Nominal CS 2.1
Imaging Mode BRIGHT FIELD
Specimen Holder Model ?
Nominal Magnification 50000
Calibrated Magnification 48000
Source FIELD EMISSION GUN
Acceleration Voltage (kV) 200
Imaging Details low dose mode
Image Processing
CTF Correction Type CTF Correction Details Number of Particles Selected Particle Selection Details
. phase flipping CTF correction of each particle as function of position in the micrograph