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Alignment Error Envelopes for Single Particle Analysis

Jensen, Grant J. (2001) Alignment Error Envelopes for Single Particle Analysis. Journal of Structural Biology, 133 (2-3). pp. 143-155. ISSN 1047-8477. doi:10.1006/jsbi.2001.4334.

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To determine the structure of a biological particle to high resolution by electron microscopy, image averaging is required to combine information from different views and to increase the signal-to-noise ratio. Starting from the number of noiseless views necessary to resolve features of a given size, four general factors are considered that increase the number of images actually needed: (1) the physics of electron scattering introduces shot noise, (2) thermal motion and particle inhomogeneity cause the scattered electrons to describe a mixture of structures, (3) the microscope system fails to usefully record all the information carried by the scattered electrons, and (4) image misalignment leads to information loss through incoherent averaging. The compound effect of factors 2–4 is approximated by the product of envelope functions. The problem of incoherent image averaging is developed in detail through derivation of five envelope functions that account for small errors in 11 “alignment” parameters describing particle location, orientation, defocus, magnification, and beam tilt. The analysis provides target error tolerances for single particle analysis to near-atomic (3.5 Å) resolution, and this prospect is shown to depend critically on image quality, defocus determination, and microscope alignment.

Item Type:Article
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URLURL TypeDescription
Jensen, Grant J.0000-0003-1556-4864
Additional Information:© 2001 Academic Press. Received 14 November 2000, Revised 8 January 2001. The author thanks Kenneth Downing for extensive discussions and comments on the manuscript, as well as Robert Glaeser, David DeRosier, Nigel Unwin, and Roger Kornberg for critically reading the text. The author was supported by the Cancer Research Fund of the Damon Runyon–Walter Winchell Foundation Fellowship, DRG-#1591, and by Medical Scientist Training Program Grant GM07365 provided by the National Institutes of Health.
Funding AgencyGrant Number
Damon Runyon-Walter Winchell Cancer FundDRG-1591
Subject Keywords:alignment; electron microscopy; envelope functions; image processing; resolution; single particle analysis
Issue or Number:2-3
Record Number:CaltechAUTHORS:20181213-110052609
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Official Citation:Grant J. Jensen, Alignment Error Envelopes for Single Particle Analysis, Journal of Structural Biology, Volume 133, Issues 2–3, 2001, Pages 143-155, ISSN 1047-8477, (
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:91765
Deposited By: George Porter
Deposited On:13 Dec 2018 22:15
Last Modified:16 Nov 2021 03:44

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