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A deazariboflavin chromophore kinetically stabilizes reduced FAD state in a bifunctional cryptochrome.

ABSTRACT: An animal-like cryptochrome derived from Chlamydomonas reinhardtii (CraCRY) is a bifunctional flavoenzyme harboring flavin adenine dinucleotide (FAD) as a photoreceptive/catalytic center and functions both in the regulation of gene transcription and the repair of UV-induced DNA lesions in a light-dependent manner, using different FAD redox states. To address how CraCRY stabilizes the physiologically relevant redox state of FAD, we investigated the thermodynamic and kinetic stability of the two-electron reduced anionic FAD state (FADH^-) in CraCRY and related (6-4) photolyases. The thermodynamic stability of FADH^- remained almost the same compared to that of all tested proteins. However, the kinetic stability of FADH^- varied remarkably depending on the local structure of the secondary pocket, where an auxiliary chromophore, 8-hydroxy-7,8-didemethyl-5-deazariboflavin (8-HDF), can be accommodated. The observed effect of 8-HDF uptake on the enhancement of the kinetic stability of FADH^- suggests an essential role of 8-HDF in the bifunctionality of CraCRY.

SUBMITTER: Hosokawa Y

PROVIDER: S-EPMC10551024 | biostudies-literature | 2023 Oct

REPOSITORIES: biostudies-literature

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A deazariboflavin chromophore kinetically stabilizes reduced FAD state in a bifunctional cryptochrome.

Hosokawa Yuhei Y Morita Hiroyoshi H Nakamura Mai M Yamamoto Junpei J

Scientific reports 20231004 1

An animal-like cryptochrome derived from Chlamydomonas reinhardtii (CraCRY) is a bifunctional flavoenzyme harboring flavin adenine dinucleotide (FAD) as a photoreceptive/catalytic center and functions both in the regulation of gene transcription and the repair of UV-induced DNA lesions in a light-dependent manner, using different FAD redox states. To address how CraCRY stabilizes the physiologically relevant redox state of FAD, we investigated the thermodynamic and kinetic stability of the two-e ...[more]

PMID: 37794070

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A deazariboflavin chromophore kinetically stabilizes reduced FAD state in a bifunctional cryptochrome.

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A deazariboflavin chromophore kinetically stabilizes reduced FAD state in a bifunctional cryptochrome.

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