5LZB

Structure of SelB-Sec-tRNASec bound to the 70S ribosome in the initial binding state (IB)


ELECTRON MICROSCOPY
Sample
Initial binding state of E. coli ribosome 70S-SelB-GDPNP-Sec-tRNASec-fMet-tRNAfmet-SECIS mRNA complex (IB)
Specimen Preparation
Sample Aggregation StatePARTICLE
Vitrification InstrumentFEI VITROBOT MARK IV
Cryogen NameETHANE
Sample Vitrification Details
3D Reconstruction
Reconstruction MethodSINGLE PARTICLE
Number of Particles8002
Reported Resolution (Å)5.3
Resolution MethodFSC 0.143 CUT-OFF
Other DetailsGold-standard refinement of independent half maps in Relion 1.3
Refinement Type
Symmetry TypePOINT
Map-Model Fitting and Refinement
Id1
Refinement Space
Refinement ProtocolFLEXIBLE FIT
Refinement TargetMaximum likelihood
Overall B Value
Fitting Procedure
DetailsFor parts of the model exhibiting larger conformational differences and/or lower local map resolution, additional cycles of real space refinement and ...For parts of the model exhibiting larger conformational differences and/or lower local map resolution, additional cycles of real space refinement and manual fitting were performed against experimental map filtered to lower resolution
Data Acquisition
Detector TypeFEI FALCON II (4k x 4k)
Electron Dose (electrons/Å**2)30
Imaging Experiment1
Date of Experiment
Temperature (Kelvin)
Microscope ModelFEI TITAN KRIOS
Minimum Defocus (nm)700
Maximum Defocus (nm)2600
Minimum Tilt Angle (degrees)
Maximum Tilt Angle (degrees)
Nominal CS0.001
Imaging ModeBRIGHT FIELD
Specimen Holder ModelFEI TITAN KRIOS AUTOGRID HOLDER
Nominal Magnification59000
Calibrated Magnification
SourceFIELD EMISSION GUN
Acceleration Voltage (kV)300
Imaging DetailsUsing a Cs-corrector from CEOS electron optical aberrations were corrected to residual phase errors of 45degree at scattering angles of >12 to 15 mrad.
EM Software
TaskSoftware PackageVersion
MODEL REFINEMENTRosetta3.5
MODEL REFINEMENTCoot0.8.3
MODEL REFINEMENTRCrane1.1
MODEL REFINEMENTPHENIX1.10.1 & developmental
MODEL REFINEMENTPHENIX1.10.1
RECONSTRUCTIONRELION1.3
MODEL REFINEMENTERRASER
Image Processing
CTF Correction TypeCTF Correction DetailsNumber of Particles SelectedParticle Selection Details
PHASE FLIPPING ONLYLocal CTF correction, after MSA based classification and averaging of local power spectra969526969526 ribosome particles showing Thon rings better than 3.5A (see CTF correction)