Achievable resolution from images of biological specimens acquired from a 4k x 4k CCD camera in a 300-kV electron cryomicroscope.
Bacteriorhodopsin and epsilon 15 bacteriophage were used as biological test specimens to evaluate the potential structural resolution with images captured from a 4k x 4k charge-coupled device (CCD) camera in a 300-kV electron cryomicroscope. The phase residuals computed from the bacteriorhodopsin CCD images taken at 84,000x effective magnification averaged 15.7 degrees out to 5.8-A resolution relative to Henderson's published values. Using a single-particle reconstruction technique, we obtained an 8.2-A icosahedral structure of epsilon 15 bacteriophage with the CCD images collected at an effective magnification of 56,000x. These results demonstrate that it is feasible to retrieve biological structures to a resolution close to 2/3 of the Nyquist frequency from the CCD images recorded in a 300-kV electron cryomicroscope at a moderately high but practically acceptable microscope magnification.
Chen
Dong-Hua
DH
National Center for Macromolecular Imaging, Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA.
Jakana
Joanita
J
Liu
Xiangan
X
Schmid
Michael F
MF
Chiu
Wah
W
D001435:Bacteriophages / Q000648:ultrastructure; D001436:Bacteriorhodopsins / Q000648:ultrastructure; D020285:Cryoelectron Microscopy / Q000295:instrumentation* / Q000592:standards; D007091:Image Processing, Computer-Assisted / Q000295:instrumentation / Q000592:standards
D001436:Bacteriorhodopsins