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Structural basis of the radical pair state in photolyases and cryptochromes.

ABSTRACT: We present the structure of a photoactivated animal (6-4) photolyase in its radical pair state, captured by serial crystallography. We observe how a conserved asparigine moves towards the semiquinone FAD chromophore and stabilizes it by hydrogen bonding. Several amino acids around the final tryptophan radical rearrange, opening it up to the solvent. The structure explains how the protein environment stabilizes the radical pair state, which is crucial for function of (6-4) photolyases and cryptochromes.

SUBMITTER: Cellini A

PROVIDER: S-EPMC9008703 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature

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Structural basis of the radical pair state in photolyases and cryptochromes.

Cellini Andrea A Shankar Madan Kumar MK Wahlgren Weixiao Yuan WY Nimmrich Amke A Furrer Antonia A James Daniel D Wranik Maximilian M Aumonier Sylvain S Beale Emma V EV Dworkowski Florian F Standfuss Jörg J Weinert Tobias T Westenhoff Sebastian S

Chemical communications (Cambridge, England) 20220414 31

We present the structure of a photoactivated animal (6-4) photolyase in its radical pair state, captured by serial crystallography. We observe how a conserved asparigine moves towards the semiquinone FAD chromophore and stabilizes it by hydrogen bonding. Several amino acids around the final tryptophan radical rearrange, opening it up to the solvent. The structure explains how the protein environment stabilizes the radical pair state, which is crucial for function of (6-4) photolyases and cryptoc ...[more]

PMID: 35352724

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