1AT9

STRUCTURE OF BACTERIORHODOPSIN AT 3.0 ANGSTROM DETERMINED BY ELECTRON CRYSTALLOGRAPHY

ELECTRON CRYSTALLOGRAPHY

Crystallization

Crystal Properties
Matthews coefficient	Solvent content
4.23	71

Crystal Data

Unit Cell
Length ( Å )	Angle ( ˚ )
a = 62.45	α = 90
b = 62.45	β = 90
c = 100	γ = 120

Symmetry
Space Group	P 3

Diffraction

Diffraction Experiment
ID #	Crystal ID	Scattering Type	Data Collection Temperature	Detector	Detector Type	Details	Collection Date	Monochromator	Protocol
1	1	electron					1992-04-01

Refinement

Statistics
Diffraction ID	Structure Solution Method	Resolution (High)	Resolution (Low)	Number Reflections (R-Free)	Percent Reflections (Observed)	R-Work	R-Free	Mean Isotropic B
ELECTRON CRYSTALLOGRAPHY		2.8

Temperature Factor Modeling
Anisotropic B[1][1]	Anisotropic B[1][2]	Anisotropic B[1][3]	Anisotropic B[2][2]	Anisotropic B[2][3]	Anisotropic B[3][3]

Non-Hydrogen Atoms Used in Refinement
Non-Hydrogen Atoms	Number
Protein Atoms	1778
Nucleic Acid Atoms
Solvent Atoms
Heterogen Atoms	20

Software

Software
Software Name	Purpose
X-PLOR	model building
X-PLOR	refinement
X-PLOR	phasing

Sample
Bacteriorhodopsin

Specimen Preparation
Sample Aggregation State	2D ARRAY
Vitrification Instrument	REICHERT-JUNG PLUNGER
Cryogen Name	ETHANE
Sample Vitrification Details	delay of 10 seconds before rapid freezing
Embedding Material	trehalose
Embedding Details	3% trehalose

3D Reconstruction
Reconstruction Method	CRYSTALLOGRAPHY
Number of Particles
Reported Resolution (Å)	2.8
Resolution Method	DIFFRACTION PATTERN/LAYERLINES
Other Details
Refinement Type
Symmetry Type	2D CRYSTAL

Data Acquisition
Detector Type	GENERIC GATAN (2k x 2k)	KODAK SO-163 FILM
Electron Dose (electrons/Å**2)	10	10

Imaging Experiment	1	2
Date of Experiment
Temperature (Kelvin)
Microscope Model	JEOL 4000	JEOL 3000SFF
Minimum Defocus (nm)
Maximum Defocus (nm)
Minimum Tilt Angle (degrees)
Maximum Tilt Angle (degrees)
Nominal CS
Imaging Mode	DIFFRACTION	BRIGHT FIELD
Specimen Holder Model
Nominal Magnification
Calibrated Magnification
Source	FIELD EMISSION GUN	FIELD EMISSION GUN
Acceleration Voltage (kV)	400	300
Imaging Details

EM Software
Task	Software Package	Version
CRYSTALLOGRAPHY MERGING	CCP4 programs

RCSB PDB Core Operations are funded by the U.S. National Science Foundation (DBI-2321666), the US Department of Energy (DE-SC0019749), and the National Cancer Institute, National Institute of Allergy and Infectious Diseases, and National Institute of General Medical Sciences of the National Institutes of Health under grant R01GM157729.