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Updated: Feb 12, 2026

Characterization at the Molecular Level using Robust Biochemical Approaches of a New Kinase Protein
Published on: June 30, 2019
Characterizing the binding interactions of PFOA and PFOS with catalase at the molecular level
Mengchen Xu1, Zhaohao Cui1, Lining Zhao1
1School of Environmental Science and Engineering, Shandong University, China -America CRC for Environment & Health, Shandong Province, 27# Shanda Nanlu, Jinan 250100, PR China.
Abstract:
Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) have effects on human health by inducing oxidative stress and catalase (CAT) is a vital enzyme involved in protection against oxidative damage. The interactions of PFOA and PFOS with CAT were investigated by using biophysical methods including spectroscopic techniques, molecular docking and enzyme activity measurements. UV-visible, circular dichroism (CD) and resonance light scattering (RLS) spectroscopy results showed that the structure and conformation of CAT were changed by PFOA and PFOS. PFOA could loosen and unfold the skeleton of CAT but PFOS affected the microenvironment around the aromatic amino acid residues and heme groups. Both PFOA and PFOS altered the secondary structure of CAT by decreasing α-helix and increasing β-sheet content. The size of CAT was smaller and CAT became dispersed when it was bound by perfluorinated compounds (PFCs). Furthermore, enzyme activity test showed that PFOS decreased the activity of CAT because the binding site of PFOS was close to the active center of CAT, but PFOA had little effect on the activity because PFOA bound at the surface of the enzyme. These results indicated that PFCs could damage the structures and conformations of CAT but the changes were not always related to the activity and function of CAT.
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