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Microcrystal electron diffraction, commonly referred to as MicroED, has become a powerful tool for high-resolution structure determination. The method makes use of cryogenic transmission electron microscopes to collect electron diffraction data from crystals that are several orders of magnitude smaller than those used by other conventional diffraction techniques. MicroED has been used on a variety of samples including soluble proteins, membrane proteins, small organic molecules, and materials. Here we will review the MicroED method and highlight recent advancements to the methodology, as well as describe applications of MicroED within the fields of structural biology and chemical crystallography.
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Absolute structure determination of Berkecoumarin by X-ray and electron diffraction
X-ray and electron diffraction methods independently identify the S-enantiomer of Berkecoumarin [systematic name: (S)-8-hydroxy-3-(2-hydroxypropyl)-6-methoxy-2H-chromen-2-one]. Isolated from Berkeley Pit Lake Penicillium sp., Berkecoumarin is a natural product with a light-atom composition (C13H14O5) that challenges in-house absolute structure determination by anomalous scattering. This study further demonstrates the utility of dynamical refinement of electron-diffraction data for absolute structure determination.
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- Award ID(s):
- 2132227
- PAR ID:
- 10609391
- Publisher / Repository:
- International Union of Crystallography (co-published with Wiley)
- Date Published:
- Journal Name:
- Acta Crystallographica Section C Structural Chemistry
- Volume:
- 80
- Issue:
- 5
- ISSN:
- 2053-2296
- Page Range / eLocation ID:
- 143 to 147
- Subject(s) / Keyword(s):
- crystal structure absolute structure determination electron diffraction microED dynamical refinement Berkecoumarin chromenone coumarin natural product.
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1107/S2053229624003061
