Download MendeleyCharacterization of LOV domain-ribityllumazine complex with blue-shifted fluorescence.
Kuznetsova, E., Afanasev, A., Nikolaev, A., Natarov, I., Semenov, O., Mikhailov, A.E., Borshchevskiy, V., Yang, Y., Belozerova, O.A., Dubinnyi, M.A., Shlykov, M.A., Maksimov, E.G., Remeeva, A., Gushchin, I.(2026) Biochem Biophys Res Commun 836: 154582-154582
- PubMed: 42743751 Search on PubMed
- DOI: https://doi.org/10.1016/j.bbrc.2026.154582
- Primary Citation Related Structures:
44OO - PubMed Abstract:
Flavin-based fluorescent proteins (FbFPs) are small tags derived from natural LOV domains that can be used for anaerobic imaging. However, their applications are limited due to absence of strongly color-shifted variants. Here, we explore the possibility of reconstituting an FbFP with 6,7-dimethyl-8-ribityllumazine (LUM), an endogenous biosynthetic precursor of riboflavin (RF). We show that CagFbFP binds LUM with low-micromolar affinity (Kd = 9.5 ± 1.1 μM), forming a fluorescent complex with the excitation maximum at 419 nm and emission maximum at 462 nm. Under blue-light irradiation, CagFbFP-bound LUM is converted irreversibly to 6,7-dimethyllumazine, whereas the more traditional chromophore RF undergoes reversible reduction to hydroquinone form. Crystal structure of the CagFbFP-LUM complex determined at the anisotropic resolution reaching 1.27 Å confirms that the chromophore occupies the canonical flavin-binding pocket. The obtained results pave the way towards engineering of LUM-based FbFP variants with blue-shifted fluorescence emission.
- Moscow Center for Advanced Studies, Moscow, 123592, Russia.
Organizational Affiliation:
