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With time-resolved crystallography (TRX), it is possible to follow the reaction dynamics in biological macromolecules by investigating the structure of transient states along the reaction coordinate. X-ray free electron lasers (XFELs) have enabled TRX experiments on previously uncharted femtosecond timescales. Here, we review the recent developments, opportunities, and challenges of pump-probe TRX at XFELs.
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Practical considerations for the analysis of time-resolved x-ray data
The field of time-resolved macromolecular crystallography has been expanding rapidly after free electron lasers for hard x rays (XFELs) became available. Techniques to collect and process data from XFELs spread to synchrotron light sources. Although time-scales and data collection modalities can differ substantially between these types of light sources, the analysis of the resulting x-ray data proceeds essentially along the same pathway. At the base of a successful time-resolved experiment is a difference electron density (DED) map that contains chemically meaningful signal. If such a difference map cannot be obtained, the experiment has failed. Here, a practical approach is presented to calculate DED maps and use them to determine structural models.
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- Award ID(s):
- 1231306
- PAR ID:
- 10589280
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- Structural Dynamics
- Volume:
- 10
- Issue:
- 4
- ISSN:
- 2329-7778
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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