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bioRxiv · 10.1101/2025.03.25.645188

STUDIES ON INTERACTION OF MORIN WITH CURLI TO IDENTIFY AGGREGATION NATURE

Roy, T.·Bhat, N.·Sengupta, S.·Banik, S. P.·Bhattacharyya, M.·Basak, P.
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Abstract

Morin (3,5,7,2',4'-pentahydroxyflavone) is a flavonoid compound exhibited a range of biological functions, including anti-inflammatory, antioxidant, antiviral, and anti-allergic activities. It has the ability to disaggregate amyloid fibrils, making it a potential inhibitor of diseases caused by amyloid protein fibrillation. This study focuses on the interaction between Morin and Curli amyloid fibrils, which are produced by some Enterobacteriaceae, including Salmonella sp. And E. coli, as a major component of their biofilms. The Curli amyloid fibrils can lead to neurodegenerative diseases through a signalling cascade causing various human diseases, such as Alzheimers and Huntingtons diseases. Thioflavin T (ThT) fluorescence assays to purified Curli, and molecular docking between Morin and Curli indicates nature of binding at molecular level. The results showed that Morin quenched Curli fluorescence in a concentration-dependent manner, indicating dynamic quenching. Stern-Volmer analysis revealed that Morin binds to Curli with a binding constant of approximately 102 L/mol. This binding was found to be spontaneous, with hydrophobic interactions playing a significant role. ThT fluorescence assays confirmed that Morin inhibited Curli fibrillation, suggesting a potential therapeutic application. Molecular docking analysis revealed specific interactions between Morin and Curli, providing insights into their binding at the molecular level. In conclusion, this study demonstrates the dynamic quenching of Curli fluorescence by Morin and suggested that Morin may inhibit Curli fibrillation, making it a valuable candidate for the development of therapeutic drugs.

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Roy, T., Bhat, N., Sengupta, S., Banik, S. P., Bhattacharyya, M., Basak, P.. 2025-03-27. STUDIES ON INTERACTION OF MORIN WITH CURLI TO IDENTIFY AGGREGATION NATURE. https://doi.org/10.1101/2025.03.25.645188

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