Design and Development of Substrate-based Peptide Inhibitors Targeting the Chymotrypsin Like Protease of SARS-CoV-2
Disciplines
Biochemistry
Abstract (300 words maximum)
With COVID-19 numbers on the rise yet again, recent drug development and research has supported the use of peptide therapeutics as an alternative to current treatments. In many commercial pharmacies, small-molecule drugs, such as Paxlovid, are a common mode of treatment against the SARS-CoV-2 virus. These small-molecule drugs, though, often induce harmful and off-target effects that lead to therapy resistance upon prolonged use. In this study, we investigated the substrate-based peptide inhibitors targeting the Chymotrypsin Like Protease (3CLpro). Identifying probable antiviral agents targeting the 3CLpro of SARS-CoV-2 can effectively inhibit the active site on the main protease and hinder its cleaving potential, therefore decreasing the rate of viral replication. A substrate-based peptide inhibitor was synthesized using CEM Liberty Blue peptide synthesizer with automated Fmoc solid phase synthesis protocols. The Rink-amide resin with a loading capacity of 0.58 mmol/g was used under a high-swelling condition. The peptide was synthesized by employing repeated deprotection and coupling reactions. The resulting peptide-resin complex was cleaved using a 95% trifluoracetic acid (TFA) mixture. The peptide was then precipitated and purified using diethyl ester. The synthesis of the peptide was authenticated by mass spectrometry. The peptide showed a strong peak at m/z 1393.75 corresponded to [M+H]+ ions which matched with the theoretical mass. A LCMS (liquid chromatography coupled with mass spectrometry) based selected ion monitoring assay was conducted to test the inhibition efficiency of the peptide. The peptide displayed an IC50 value of 6.38 micromolar for the first run and 5.04 micromolar for the second.
Academic department under which the project should be listed
CSM - Chemistry and Biochemistry
Primary Investigator (PI) Name
Mohammad A. Halim
Design and Development of Substrate-based Peptide Inhibitors Targeting the Chymotrypsin Like Protease of SARS-CoV-2
With COVID-19 numbers on the rise yet again, recent drug development and research has supported the use of peptide therapeutics as an alternative to current treatments. In many commercial pharmacies, small-molecule drugs, such as Paxlovid, are a common mode of treatment against the SARS-CoV-2 virus. These small-molecule drugs, though, often induce harmful and off-target effects that lead to therapy resistance upon prolonged use. In this study, we investigated the substrate-based peptide inhibitors targeting the Chymotrypsin Like Protease (3CLpro). Identifying probable antiviral agents targeting the 3CLpro of SARS-CoV-2 can effectively inhibit the active site on the main protease and hinder its cleaving potential, therefore decreasing the rate of viral replication. A substrate-based peptide inhibitor was synthesized using CEM Liberty Blue peptide synthesizer with automated Fmoc solid phase synthesis protocols. The Rink-amide resin with a loading capacity of 0.58 mmol/g was used under a high-swelling condition. The peptide was synthesized by employing repeated deprotection and coupling reactions. The resulting peptide-resin complex was cleaved using a 95% trifluoracetic acid (TFA) mixture. The peptide was then precipitated and purified using diethyl ester. The synthesis of the peptide was authenticated by mass spectrometry. The peptide showed a strong peak at m/z 1393.75 corresponded to [M+H]+ ions which matched with the theoretical mass. A LCMS (liquid chromatography coupled with mass spectrometry) based selected ion monitoring assay was conducted to test the inhibition efficiency of the peptide. The peptide displayed an IC50 value of 6.38 micromolar for the first run and 5.04 micromolar for the second.