Interaction mechanisms between organic UV filters and bovine serum albumin as determined by comprehensive spectroscopy exploration and molecular docking. (January 2015)

• Record Type: Journal Article
• Authors: Ao, Junjie; Gao, Li; Yuan, Tao; Jiang, Gaofeng
• Is Part Of: Chemosphere. Volume 119(2015)
• Page Start: 590
• Page End: 600
• Publication Date: 2015-01
• Subjects: Interaction mechanisms -- Organic UV filters -- Bovine serum albumin -- Spectroscopy -- Molecular docking; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2014.07.019
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract : Graphical abstract: Highlights: BSA fluorescence is quenched by five commonly-used UV filters. UV filters can extend the BSA polypeptide chain and disrupt its α-helical stability. UV filter molecules bind in site II (subdomain IIIA) of BSA by docking. Abstract: Organic UV filters are a group of emerging PPCP (pharmaceuticals and personal care products) contaminants. Current information is insufficient to understand the in vivo processes and health risks of organic UV filters in humans. The interaction mechanism of UV filters with serum albumin provides critical information for the health risk assessment of these active ingredients in sunscreen products. This study investigates the interaction mechanisms of five commonly used UV filters (2-hydroxy-4-methoxybenzophenone, BP-3; 2-ethylhexyl 4-methoxycinnamate, EHMC; 4-methylbenzylidene camphor, 4-MBC; methoxydibenzoylmethane, BDM; homosalate, HMS) with bovine serum albumin (BSA) by spectroscopic measurements of fluorescence, circular dichroism (CD), competitive binding experiments and molecular docking. Our results indicated that the fluorescence of BSA was quenched by these UV filters through a static quenching mechanism. The values of the binding constant ( K a ) ranged from (0.78 ± 0.02) × 10 3 to (1.29 ± 0.01) × 10 5 L mol −1 . Further exploration by synchronous fluorescence and CD showed that the conformation of BSA was demonstrably changed in the presence of these organic UV filters. It was confirmed that the UV filters can disrupt the α-helical stability of BSA. Moreover, the results of molecular docking revealed that the UV filter molecule is located in site II (sub-domain IIIA) of BSA, which was further confirmed by the results of competitive binding experiments. In addition, binding occurred mainly through hydrogen bonding and hydrophobic interaction. This study raises critical concerns regarding the transportation, distribution and toxicity effects of organic UV filters in human body.