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Three-dimensional reconstruction of helical polymers.

ABSTRACT: The field of three-dimensional electron microscopy began more than 45years ago with a reconstruction of a helical phage tail, and helical polymers continue to be important objects for three-dimensional reconstruction due to the centrality of helical protein and nucleoprotein polymers in all aspects of biology. We are now witnessing a fundamental revolution in this area, made possible by direct electron detectors, which has led to near-atomic resolution for a number of important helical structures. Most importantly, the possibility of achieving such resolution routinely for a vast number of helical samples is within our reach. One of the main problems in helical reconstruction, ambiguities in assigning the helical symmetry, is overcome when one reaches a resolution where secondary structure is clearly visible. However, obstacles still exist due to the intrinsic variability within many helical filaments.

SUBMITTER: Egelman EH

PROVIDER: S-EPMC4543434 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature

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Three-dimensional reconstruction of helical polymers.

Egelman Edward H EH

Archives of biochemistry and biophysics 20150422

The field of three-dimensional electron microscopy began more than 45years ago with a reconstruction of a helical phage tail, and helical polymers continue to be important objects for three-dimensional reconstruction due to the centrality of helical protein and nucleoprotein polymers in all aspects of biology. We are now witnessing a fundamental revolution in this area, made possible by direct electron detectors, which has led to near-atomic resolution for a number of important helical structure ...[more]

PMID: 25912526

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