Back to Search
Start Over
Serial femtosecond X-ray crystallography of an anaerobically formed catalytic intermediate of copper amine oxidase
- Source :
- Acta crystallographica. Section D, Structural biology. 78(Pt 12)
- Publication Year :
- 2022
-
Abstract
- The mechanisms by which enzymes promote catalytic reactions efficiently through their structural changes remain to be fully elucidated. Recent progress in serial femtosecond X-ray crystallography (SFX) using X-ray free-electron lasers (XFELs) has made it possible to address these issues. In particular, mix-and-inject serial crystallography (MISC) is promising for the direct observation of structural changes associated with ongoing enzymic reactions. In this study, SFX measurements using a liquid-jet system were performed on microcrystals of bacterial copper amine oxidase anaerobically premixed with a substrate amine solution. The structure determined at 1.94 Å resolution indicated that the peptidyl quinone cofactor is in equilibrium between the aminoresorcinol and semiquinone radical intermediates, which accumulate only under anaerobic single-turnover conditions. These results show that anaerobic conditions were well maintained throughout the liquid-jet SFX measurements, preventing the catalytic intermediates from reacting with dioxygen. These results also provide a necessary framework for performing time-resolved MISC to study enzymic reaction mechanisms under anaerobic conditions.
Details
- ISSN :
- 20597983
- Volume :
- 78
- Issue :
- Pt 12
- Database :
- OpenAIRE
- Journal :
- Acta crystallographica. Section D, Structural biology
- Accession number :
- edsair.doi.dedup.....53e143630c7ae1d22e74b4108a19d02f