Serial Femtosecond Crystallography Reveals that Photoactivation in a Fluorescent Protein Proceeds via the Hula Twist Mechanism
Year of publication
2023
Authors
Fadini, Alisia; Hutchison, Christopher D. M.; Morozov, Dmitry; Chang, Jeffrey; Maghlaoui, Karim; Perrett, Samuel; Luo, Fangjia; Kho, Jeslyn C. X.; Romei, Matthew G.; Morgan, R. Marc L.; Orr, Christian M.; Cordon-Preciado, Violeta; Fujiwara, Takaaki; Nuemket, Nipawan; Tosha, Takehiko; Tanaka, Rie; Owada, Shigeki; Tono, Kensuke; Iwata, So; Boxer, Steven G.; Groenhof, Gerrit; Nango, Eriko; van Thor, Jasper J.
Show moreAbstract
Chromophore cis/trans photoisomerization is a fundamental process in chemistry and in the activation of many photosensitive proteins. A major task is understanding the effect of the protein environment on the efficiency and direction of this reaction compared to what is observed in the gas and solution phases. In this study, we set out to visualize the hula twist (HT) mechanism in a fluorescent protein, which is hypothesized to be the preferred mechanism in a spatially constrained binding pocket. We use a chlorine substituent to break the twofold symmetry of the embedded phenolic group of the chromophore and unambiguously identify the HT primary photoproduct. Through serial femtosecond crystallography, we then track the photoreaction from femtoseconds to the microsecond regime. We observe signals for the photoisomerization of the chromophore as early as 300 fs, obtaining the first experimental structural evidence of the HT mechanism in a protein on its femtosecond-to-picosecond timescale. We are then able to follow how chromophore isomerization and twisting lead to secondary structure rearrangements of the protein β-barrel across the time window of our measurements.
Show moreOrganizations and authors
Publication type
Publication format
Article
Parent publication type
Journal
Article type
Original article
Audience
ScientificPeer-reviewed
Peer-ReviewedMINEDU's publication type classification code
A1 Journal article (refereed), original researchPublication channel information
Publisher
Volume
145
Issue
29
Pages
15796-15808
ISSN
Publication forum
Publication forum level
3
Open access
Open access in the publisher’s service
Yes
Open access of publication channel
Partially open publication channel
Self-archived
Yes
Other information
Fields of science
Chemical sciences
Keywords
[object Object],[object Object],[object Object]
Publication country
United States
Internationality of the publisher
International
Language
English
International co-publication
Yes
Co-publication with a company
No
DOI
10.1021/jacs.3c02313
The publication is included in the Ministry of Education and Culture’s Publication data collection
Yes