Ginkgolic acid and anacardic acid are reversible inhibitors of SARS-CoV-2 3-chymotrypsin-like protease

Abstract

Because of the emerging variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in different regions of the world, the battle with infectious coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 has been seesawing. Therefore, the identification of antiviral drugs is of particular importance. In order to rapidly identify inhibitors for SARS-CoV-2 3-chymotrypsin-like protease (3CLpro), an enzyme essential for viral replication, we combined the fluorescence polarization (FP) technique with biotin-avidin system (BAS) and developed a novel sandwich-like FP screening assay. Through high-throughput screening, two hits of 3CLpro inhibitors, ginkgolic acid (GA) and anacardic acid (AA) were identified, which showed IC50 values of 11.29 ± 0.48 and 12.19 ± 0.50 μM, respectively. Their binding modes were evaluated by HPLC-Q-TOF–MS. There was no mass increase detected for SARS-CoV-2 3CLpro incubated with either GA or AA, indicating the absence of covalent adducts. The kinetic analysis clearly demonstrated that both GA and AA inhibit SARS-CoV-2 3CLpro via reversible and mixed-inhibition manner. Our results argue against conclusion that GA and AA act as irreversible and covalent inhibitors against SARS-CoV-2 3CLpro, which is based on the studies by Chen et al.

A robust high-throughput fluorescence polarization assay for rapid screening of SARS-CoV-2 papain-like protease inhibitors

“…Anacardic acid is the main component of extracts from Ginkgo biloba and Rhus verniciflua , which has a wide range of pharmacological activities such as antibacterial, anticancer, and antiviral ( Hundt et al, 2015 ; Park et al, 2018 ; Saedtler et al, 2020 ). Recent studies have confirmed that the EC 50 value of antiviral activity of anacardic acid is 9 μM in live SARS-CoV-2 virus by targeting Mpro ( Chen et al, 2021b ; Hicks et al, 2022 ; Li et al, 2022 ; Xiong et al, 2021 ; Yan et al, 2022b ). Our study demonstrated that anacardic acid is likely a novel competitive inhibitor targeting both PLpro and Mpro of SARS-CoV-2, and more in vivo experiments for its antiviral mechanism will be explored in the future.…”

“…However, its success rate depends not only on the capacity and diversity of screened chemical libraries, but also on the robustness, convenience, and cost efficiency of the HTS assays ( Shan et al, 2021 ). As a homogenous biochemical assay, our research group has successfully utilized FP technique for screening of protein-protein interaction antagonists and Mpro inhibitors ( Chen et al, 2017 , 2021a ; Li et al, 2022 ; Yan et al, 2021 , 2022b ). At present, the discovery of PLpro inhibitors mainly relies on FRET and cell-based screening assays, but these approaches often face more obstacles in a large-scale screening.…”

Design and Evaluation of Dual Release from Anacardic Acid-Based Polyurea Nanocapsules Components

“…Furthermore, a study 18 has investigated photoprotective and anti-inflammatory activities of AA in human skin. Recently, other studies 19,20 indicated that the anacardic acid inhibit severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) replication in vitro at nontoxic concentrations. The results provide a novel natural product as promising SARS-CoV-2 antiviral.…”

“…The results provide a novel natural product as promising SARS-CoV-2 antiviral. 19,20 Polymer nanoparticles have become highly promising candidates for the transport and release of drugs mainly because they provide means for delivering active molecules in controlled time and site specifically. [21][22][23] Several works [24][25][26][27][28] have been developed in the preparation of polymeric nanoparticles via miniemulsion.…”

In Vitro, In Vivo, and In Silico Activities of Ginkgolic Acid C15:1 against Streptococcus agalactiae Clinical Isolates

“…GA (15:1) has a 15-carbon chain with a double bond at the C6 position of the salicylic acid. Numerous pharmacological effects of GA (15:1) have been demonstrated including the ability to inhibit protein SUMOylation, promote tumor cell apoptosis, block HIV protease activity, and act as reversible inhibitors of SARS-CoV-2 3-chymotrypsin-like protease. − According to previous studies, GA (15:1) displays antibacterial and antibiofilm activities against Staphylococcus aureus, Bacillus amyloliquefaciens, Streptococcus thermophiles, and Enterococcus faecalis. , However, the influence of GA (15:1) on the growth of planktonic cells and biofilms of S. agalactiae in vitro and in vivo is yet unknown.…”