7ONB | pdb_00007onb

Structure of the U2 5' module of the A3'-SSA complex

ELECTRON MICROSCOPY

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Starting Model(s)

Initial Refinement Model(s)
Type	Source	Accession Code	Details
experimental model	PDB	7B9C
experimental model	PDB	6FF4
experimental model	PDB	6FF7

Refinement

RMS Deviations
Key	Refinement Restraint Deviation
f_dihedral_angle_d	9.3998
f_angle_d	0.8958
f_chiral_restr	0.0609
f_plane_restr	0.0067
f_bond_d	0.0049

Sample
The U2 5' module of the A3'-SSA complex
Sample Components
The U2 5' module of the A3'-SSA complex
MINX

Specimen Preparation
Sample Aggregation State	PARTICLE
Vitrification Instrument	FEI VITROBOT MARK IV
Cryogen Name	ETHANE
Sample Vitrification Details	The A3'-SSA complex was frozen in vitreous ice by applying ~2.2 uL crosslinked sample to both sides of a glow-discharged UltrAufoil R1.2/1.3 gold grid. The excess sample was blotted away for 2s using a blot force of 7 and the grid was snap frozen in liquid ethane cooled by liquid nitrogen.

3D Reconstruction
Reconstruction Method	SINGLE PARTICLE
Number of Particles	78262
Reported Resolution (Å)	3.1
Resolution Method	FSC 0.143 CUT-OFF
Other Details
Refinement Type
Symmetry Type	POINT
Point Symmetry	C1

Map-Model Fitting and Refinement
Id	1 (7B9C, 6FF4, 6FF7)
Refinement Space	REAL
Refinement Protocol	OTHER
Refinement Target
Overall B Value
Fitting Procedure
Details

Data Acquisition
Detector Type	GATAN K3 (6k x 4k)
Electron Dose (electrons/Å**2)	41.41

Imaging Experiment	1
Date of Experiment
Temperature (Kelvin)
Microscope Model	FEI TITAN KRIOS
Minimum Defocus (nm)	1000
Maximum Defocus (nm)	2500
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	81000
Calibrated Magnification	81000
Source	FIELD EMISSION GUN
Acceleration Voltage (kV)	300
Imaging Details

EM Software
Task	Software Package	Version
PARTICLE SELECTION	Warp
IMAGE ACQUISITION	SerialEM
CTF CORRECTION	Warp
MODEL FITTING	Coot	0.9.2
MODEL FITTING	UCSF Chimera
MODEL REFINEMENT	PHENIX	1.19-4092
INITIAL EULER ASSIGNMENT	RELION	3.0.8
FINAL EULER ASSIGNMENT	RELION	3.1 beta
CLASSIFICATION	RELION	3.1 beta
RECONSTRUCTION	RELION	3.1 beta

Image Processing
CTF Correction Type	CTF Correction Details	Number of Particles Selected	Particle Selection Details
PHASE FLIPPING AND AMPLITUDE CORRECTION		1052001