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Image Processing in Cryo-Electron Microscopy of Single Particles: The Power of Combining Methods

Part of the Methods in Molecular Biology book series (MIMB,volume 2305)

Abstract

Cryo-electron microscopy has established as a mature structural biology technique to elucidate the three-dimensional structure of biological macromolecules. The Coulomb potential of the sample is imaged by an electron beam, and fast semi-conductor detectors produce movies of the sample under study. These movies have to be further processed by a whole pipeline of image-processing algorithms that produce the final structure of the macromolecule. In this chapter, we illustrate this whole processing pipeline putting in value the strength of “meta algorithms,” which are the combination of several algorithms, each one with different mathematical rationale, in order to distinguish correctly from incorrectly estimated parameters. We show how this strategy leads to superior performance of the whole pipeline as well as more confident assessments about the reconstructed structures. The “meta algorithms” strategy is common to many fields and, in particular, it has provided excellent results in bioinformatics. We illustrate this combination using the workflow engine, Scipion.

Key words

  • Single particle
  • Cryo-electron microscopy
  • Image processing
  • Scipion

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  • DOI: 10.1007/978-1-0716-1406-8_13
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Acknowledgments

The authors would like to acknowledge economical support from: The Spanish Ministry of Economy and Competitiveness through Grants BIO2016-76400-R(AEI/FEDER, UE), the “Comunidad Autónoma de Madrid” through Grant: S2017/BMD-3817. Instituto de Salud Carlos III through Grant: PT17/0009/0010 (ISCIII-SGEFI / ERDF). European Union (EU) and Horizon 2020 through grants: CORBEL (INFRADEV-1-2014-1, Proposal: 654248) Instruct ULTRA (Proposal: 731005), EOSC Life (Proposal: 824087), HighResCells (Proposal: 810057), IMpaCT (Proposal: 857203), EOSC—Synergy (Proposal: 857647), iNEXT-Discovery (Proposal: 871037), and European Regional Development Fund-Project “CERIT Scientific Cloud” (No. CZ.02.1.01/0.0/0.0/16_013/0001802). The authors acknowledge the support and the use of resources of Instruct, a Landmark ESFRI project.

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Correspondence to Carlos Oscar S. Sorzano .

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Sorzano, C.O.S. et al. (2021). Image Processing in Cryo-Electron Microscopy of Single Particles: The Power of Combining Methods. In: Owens, R.J. (eds) Structural Proteomics. Methods in Molecular Biology, vol 2305. Humana, New York, NY. https://doi.org/10.1007/978-1-0716-1406-8_13

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  • DOI: https://doi.org/10.1007/978-1-0716-1406-8_13

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