Development of a Fluorescence Polarization Assay for the SARS-CoV-2 Papain-like Protease

This is the authors' abstract. We don't add key points for this paper.

High Resolution Image Download MS PowerPoint Slide The COVID-19 pandemic has caused significant losses to the global community. Although effective vaccination and antiviral therapeutics provide primary defense, SARS-CoV-2 remains a public health threat, given the emerging resistant variants. The SARS-CoV-2 papain-like protease (PL pro ) is essential for viral replication and is a promising drug target. We recently designed a series of biarylphenyl PL pro inhibitors with a representative lead Jun12682 showing potent antiviral efficacy in a SARS-CoV-2 infection mouse model. In this study, we designed a fluorescein-labeled biarylphenyl probe Jun12781 and used it to optimize a fluorescence polarization (FP) assay. The FP assay is suitable for high-throughput screening with a Z ′ factor of 0.69. In addition, we found a positive correlation between the FP binding affinity and the enzymatic inhibitory potency of PL pro inhibitors, suggesting that the FP assay is valid in characterizing the binding affinity of PL pro inhibitors.