Experiment: 4CC8

Pre-fusion structure of trimeric HIV-1 envelope glycoprotein determined by cryo-electron microscopy

ELECTRON MICROSCOPY

Starting Model(s)

Initial Refinement Model(s)
Type	Source	Accession Code	Details
experimental model	PDB	3SE8
experimental model	PDB	3HMG

Sample
COMPLEX OF KNH1144 SOSIP GP140 TRIMER WITH VRC03 FAB.

Specimen Preparation
Sample Aggregation State	PARTICLE
Vitrification Instrument	FEI VITROBOT MARK IV
Cryogen Name	ETHANE
Sample Vitrification Details	BLOT FOR 6 SECONDS, BLOT OFFSET OF -2, PLUNGE INTO AN ETHANE SLURRY COOLED BY LIQUID NITROGEN

3D Reconstruction
Reconstruction Method	SINGLE PARTICLE
Number of Particles	88125
Reported Resolution (Å)	6
Resolution Method
Other Details	3SE8, CHAIN G AND CHAINS H, L FITTED AS TWO SEPARATE RIGID BODIES INTO MAP. ONLY HELIX RESIDUES 92-122 OF CHAIN B FITTED BY HAND INTO MAP. SUBMISSION ...	3SE8, CHAIN G AND CHAINS H, L FITTED AS TWO SEPARATE RIGID BODIES INTO MAP. ONLY HELIX RESIDUES 92-122 OF CHAIN B FITTED BY HAND INTO MAP. SUBMISSION BASED ON EXPERIMENTAL DATA FROM EMDB EMD-2484. (DEPOSITION ID: 12023).
Refinement Type
Symmetry Type	POINT
Point Symmetry	C3

Map-Model Fitting and Refinement
Id	1 (3SE8, 3HMG)
Refinement Space	RECIPROCAL
Refinement Protocol	RIGID BODY FIT
Refinement Target
Overall B Value
Fitting Procedure
Details	REFINEMENT PROTOCOL--RIGID BODY

Data Acquisition
Detector Type	GATAN ULTRASCAN 4000 (4k x 4k)
Electron Dose (electrons/Å**2)	10

Imaging Experiment	1
Date of Experiment	2011-08-09
Temperature (Kelvin)	80
Microscope Model	FEI TITAN KRIOS
Minimum Defocus (nm)	1500
Maximum Defocus (nm)	2500
Minimum Tilt Angle (degrees)
Maximum Tilt Angle (degrees)
Nominal CS	2.7
Imaging Mode	BRIGHT FIELD
Specimen Holder Model
Nominal Magnification	75000
Calibrated Magnification
Source	FIELD EMISSION GUN
Acceleration Voltage (kV)	80
Imaging Details

EM Software
Task	Software Package	Version
MODEL FITTING	UCSF Chimera
RECONSTRUCTION	EMAN
RECONSTRUCTION	FREALIGN
RECONSTRUCTION	IMAGIC