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Methods for merging data sets in electron cryo-microscopy.

ABSTRACT: Recent developments have resulted in electron cryo-microscopy (cryo-EM) becoming a useful tool for the structure determination of biological macromolecules. For samples containing inherent flexibility, heterogeneity or preferred orientation, the collection of extensive cryo-EM data using several conditions and microscopes is often required. In such a scenario, merging cryo-EM data sets is advantageous because it allows improved three-dimensional reconstructions to be obtained. Since data sets are not always collected with the same pixel size, merging data can be challenging. Here, two methods to combine cryo-EM data are described. Both involve the calculation of a rescaling factor from independent data sets. The effects of errors in the scaling factor on the results of data merging are also estimated. The methods described here provide a guideline for cryo-EM users who wish to combine data sets from the same type of microscope and detector.

SUBMITTER: Wilkinson ME

PROVIDER: S-EPMC6719665 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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Methods for merging data sets in electron cryo-microscopy.

Wilkinson Max E ME Kumar Ananthanarayanan A Casañal Ana A

Acta crystallographica. Section D, Structural biology 20190823 Pt 9

Recent developments have resulted in electron cryo-microscopy (cryo-EM) becoming a useful tool for the structure determination of biological macromolecules. For samples containing inherent flexibility, heterogeneity or preferred orientation, the collection of extensive cryo-EM data using several conditions and microscopes is often required. In such a scenario, merging cryo-EM data sets is advantageous because it allows improved three-dimensional reconstructions to be obtained. Since data sets ar ...[more]

PMID: 31478901

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