{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,31]],"date-time":"2026-10-31T15:04:20Z","timestamp":1793459060505,"version":"4.5.0"},"reference-count":62,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2021,6,10]],"date-time":"2021-06-10T00:00:00Z","timestamp":1623283200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Microbiol."],"abstract":"<jats:p>\n                    In the 21st century, we have witnessed three coronavirus outbreaks: SARS in 2003, MERS in 2012, and the ongoing pandemic coronavirus disease 2019 (COVID-19). The search for efficient vaccines and development and repurposing of therapeutic drugs are the major approaches in the COVID-19 pandemic research area. There are concerns about the evolution of mutant strains (e.g., VUI \u2013 202012\/01, a mutant coronavirus in the United Kingdom), which can potentially reduce the impact of the current vaccine and therapeutic drug development trials. One promising approach to counter the mutant strains is the \u201cdevelopment of effective broad-spectrum antiviral drugs\u201d against coronaviruses. This study scientifically investigates potent food bioactive broad-spectrum antiviral compounds by targeting main protease (M\n                    <jats:sup>pro<\/jats:sup>\n                    ) and papain-like protease (PL\n                    <jats:sup>pro<\/jats:sup>\n                    ) proteases of coronaviruses (CoVs) using\n                    <jats:italic>in silico<\/jats:italic>\n                    and\n                    <jats:italic>in vitro<\/jats:italic>\n                    approaches. The results reveal that phycocyanobilin (PCB) shows potential inhibitor activity against both proteases. PCB had the best binding affinity to Mpro and PLpro with IC\n                    <jats:sub>50<\/jats:sub>\n                    values of 71 and 62 \u03bcm, respectively. Also,\n                    <jats:italic>in silico<\/jats:italic>\n                    studies with M\n                    <jats:sup>pro<\/jats:sup>\n                    and PL\n                    <jats:sup>pro<\/jats:sup>\n                    enzymes of other human and animal CoVs indicate broad-spectrum inhibitor activity of the PCB. As with PCB, other phycobilins, such as phycourobilin (PUB), phycoerythrobilin (PEB), and phycoviolobilin (PVB) show similar binding affinity to SARS-CoV-2 M\n                    <jats:sup>pro<\/jats:sup>\n                    and PL\n                    <jats:sup>pro<\/jats:sup>\n                    .\n                  <\/jats:p>","DOI":"10.3389\/fmicb.2021.645713","type":"journal-article","created":{"date-parts":[[2021,6,10]],"date-time":"2021-06-10T00:57:55Z","timestamp":1623286675000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":40,"title":["Phycobilins as Potent Food Bioactive Broad-Spectrum Inhibitors Against Proteases of SARS-CoV-2 and Other Coronaviruses: A Preliminary Study"],"prefix":"10.3389","volume":"12","author":[{"given":"Brahmaiah","family":"Pendyala","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ankit","family":"Patras","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chandravanu","family":"Dash","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2021,6,10]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"48","DOI":"10.1016\/j.tmaid.2019.03.004","article-title":"Clinical predictors of mortality of Middle East Respiratory Syndrome Coronavirus (MERS-CoV) infection: a cohort study.","volume":"29","author":"Alfaraj","year":"2019","journal-title":"Travel Med. 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