Fluorescence was observed by an assay involving a synthetic fluorescently labeled peptide substrate of the type DabcylKTSAVLQ↓SGFRKME(Edans)NH2 (more than 95% purity, CPC Scientific Inc., Hangzhou, China) containing the site digested by the main protease of coronavirus. The fluorescent dye attached to the peptide substrate allows the FRET effect to be implemented [..]
HCoV-229E FRET peptide substrate

Abstract

Although the COVID-19 pandemic caused by SARS-CoV-2 viruses is officially over, the search for new effective agents with activity against a wide range of coronaviruses is still an important task for medical chemists and virologists. We synthesized a series of thiazolo-thiophenes based on (+)- and (−)-usnic acid and studied their ability to inhibit the main protease of SARS-CoV-2. Substances containing unsubstituted thiophene groups or methyl- or bromo-substituted thiophene moieties showed moderate activity. Derivatives containing nitro substituents in the thiophene heterocycle—just as pure (+)- and (−)-usnic acids—showed no anti-3CLpro activity. Kinetic parameters of the most active compound, (+)-3e, were investigated, and molecular modeling of the possible interaction of the new thiazolo-thiophenes with the active site of the main protease was carried out. We evaluated the binding energies of the ligand and protein in a ligand–protein complex. Active compound (+)-3e was found to bind with minimum free energy; the binding of inactive compound (+)-3g is characterized by higher values of minimum free energy; the positioning of pure (+)-usnic acid proved to be unstable and is accompanied by the formation of intermolecular contacts with many amino acids of the catalytic binding site. Thus, the molecular dynamics results were consistent with the experimental data. In an in vitro antiviral assay against six strains (Wuhan, Delta, and four Omicron sublineages) of SARS-CoV-2, (+)-3e demonstrated pronounced antiviral activity against all the strains.

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  • Shurtleff, V.W., Layton, M.E., Parish, C.A., Perkins, J.J., Schreier, J.D., Wang, Y., Adam, G.C., Alvarez, N., Bahmanjah, S., Bahnck-Teets, C.M. and Boyce, C.W. Journal of Medicinal Chemistry 67, no. 5 (2024): 3935-3958.

    1. Center for Discovery and Innovation, Hackensack Meridian Health. 111 Ideation Way. Nutley, New Jersey 07110, United States.
    2. Merck & Co., Inc., Rahway, New Jersey 07065, United States.

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  • Goh, Joleen Pei Zhen. Nanyang Technological University (2023)

    9 generic fluorogenic substrates (CPC Scientific) (Figure S4) were added to the final concentration of 20 μM. Fluorescence was measured at Excitation/Emission=330/390 nm on BioTek Synergy H1 microplate reader and proteolytic activity was calculated as a change in relative fluorescence units per sec using the slope of the linear range for this signal.

    January 18th, 2024Citations, Cosmetic Peptides
  • Chandramohan, A., Josien, H., Yuen, T.Y., Duggal, R., Spiegelberg, D., Yan, L., Juang, Y.C.A., Ge, L., Aronica, P.G., Kaan, H.Y.K. and Lim, Y.H. Nature Communications 15, no. 1 (2024): 489.

    1. Merck & Co., Inc., Kenilworth, NJ 07033, USA.
    2. Merck & Co., Inc., Boston, MA 02115, USA
    3. Merck & Co., Inc., West Point, PA 19486, USA
    4. Genentech, South San Francisco, CA 94080, USA

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  • Hao, Liangliang, Renee T. Zhao, Nicole L. Welch, Edward Kah Wei Tan, Qian Zhong, Nour Saida Harzallah, Chayanon Ngambenjawong et al. Nature Nanotechnology (2023): 1-10.

    All peptides and oligonucleotides were synthesized and HPLC purified by CPC Scientific and Integrated DNA Technologies (IDT), respectively. Peptide–oligonucleotide conjugates were generated by copper-free click chemistry.

  • Kikuchi, F., Ikeda, Z., Kakegawa, K., Nishikawa, Y., Sasaki, S., Fukuda, K., Takami, K., Banno, Y., Nishikawa, H., Taya, N. and Nakahata, T. Bioorganic & Medicinal Chemistry 93 (2023): 117462.

    • Research, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa 251-8555, Japan
    • Pharmaceutical Sciences, Takeda Pharmaceutical Company Ltd., 26-1, Muraoka-Higashi 2-chome, Fujisawa, Kanagawa 251-8555, Japan

    5FAM-Abu-Gly-Asp-Asp-Asp-Lys-Ile-Val-Gly-Gly-Lys(CPQ2)-Lys-Lys-NH2 (purity: 97.2%, CPC Scientific, Inc.) was diluted with an assay buffer to prepare a 5.4 μM substrate solution.

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  • Peptide Oligonucleotide Conjugate Whitepaper cover

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  • Schiemer, J., Maxwell, A., Horst, R., Liu, S., Uccello, D.P., Borzilleri, K., Rajamohan, N., Brown, M.F. and Calabrese, M.F. Nature Communications 14, no. 1 (2023): 1189.

    • Discovery Sciences, Pfizer Worldwide Research and Development, Groton, CT, USA

    After 3 h the resin was washed with binding buffer until no protein was detected, followed by elution with 0.2 mg ml−1 FLAG peptide DYKDDDDK (CPC Scientific Peptide company)

    March 1st, 2023Citations

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