Serial femtosecond X-ray crystallography of an anaerobically formed catalytic intermediate of copper amine oxidase.
Acta Crystallogr D Struct Biol
; 78(Pt 12): 1428-1438, 2022 Dec 01.
Article
em En
| MEDLINE
| ID: mdl-36458614
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 1.94â
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.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Amina Oxidase (contendo Cobre)
Idioma:
En
Revista:
Acta Crystallogr D Struct Biol
Ano de publicação:
2022
Tipo de documento:
Article
País de afiliação:
Japão