{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,28]],"date-time":"2026-02-28T04:26:57Z","timestamp":1772252817571,"version":"3.50.1"},"reference-count":51,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2020,11,28]],"date-time":"2020-11-28T00:00:00Z","timestamp":1606521600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Aims: Angiotensin-converting enzyme 2 (ACE2) plays an important role in the entry of coronaviruses into host cells. The current paper described how carnosine, a naturally occurring supplement, can be an effective drug candidate for coronavirus disease (COVID-19) on the basis of molecular docking and modeling to host ACE2 cocrystallized with nCoV spike protein. Methods: First, the starting point was ACE2 inhibitors and their structure\u2013activity relationship (SAR). Next, chemical similarity (or diversity) and PubMed searches made it possible to repurpose and assess approved or experimental drugs for COVID-19. Parallel, at all stages, the authors performed bioactivity scoring to assess potential repurposed inhibitors at ACE2. Finally, investigators performed molecular docking and modeling of the identified drug candidate to host ACE2 with nCoV spike protein. Results: Carnosine emerged as the best-known drug candidate to match ACE2 inhibitor structure. Preliminary docking was more optimal to ACE2 than the known typical angiotensin-converting enzyme 1 (ACE1) inhibitor (enalapril) and quite comparable to known or presumed ACE2 inhibitors. Viral spike protein elements binding to ACE2 were retained in the best carnosine pose in SwissDock at 1.75 Angstroms. Out of the three main areas of attachment expected to the protein\u2013protein structure, carnosine bound with higher affinity to two compared to the known ACE2 active site. LibDock score was 92.40 for site 3, 90.88 for site 1, and inside the active site 85.49. Conclusion: Carnosine has promising inhibitory interactions with host ACE2 and nCoV spike protein and hence could offer a potential mitigating effect against the current COVID-19 pandemic.<\/jats:p>","DOI":"10.3390\/molecules25235605","type":"journal-article","created":{"date-parts":[[2020,11,29]],"date-time":"2020-11-29T21:55:31Z","timestamp":1606686931000},"page":"5605","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["Carnosine to Combat Novel Coronavirus (nCoV): Molecular Docking and Modeling to Cocrystallized Host Angiotensin-Converting Enzyme 2 (ACE2) and Viral Spike Protein"],"prefix":"10.3390","volume":"25","author":[{"given":"Loai M.","family":"Saadah","sequence":"first","affiliation":[{"name":"Faculty of Pharmacy, Applied Science Private University, 11931 Amman, Jordan"},{"name":"School of Pharmaceutical Sciences, Universiti Sains Malaysia, Penang 11800, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ghina\u2019a I. Abu","family":"Deiab","sequence":"additional","affiliation":[{"name":"Faculty of Pharmacy, Yarmouk University, 21163 Irbid, Jordan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8350-900X","authenticated-orcid":false,"given":"Qosay","family":"Al-Balas","sequence":"additional","affiliation":[{"name":"Faculty of Pharmacy, Jordan University for Science &amp; Technology, 22110 Irbid, Jordan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8460-1158","authenticated-orcid":false,"given":"Iman A.","family":"Basheti","sequence":"additional","affiliation":[{"name":"Faculty of Pharmacy, Applied Science Private University, 11931 Amman, Jordan"},{"name":"Faculty of Pharmacy, The University of Sydney, Sydney 2006, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,11,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"415","DOI":"10.1007\/s40262-013-0042-0","article-title":"Prediction of Drug Disposition on the Basis of its Chemical Structure","volume":"52","author":"Stepensky","year":"2013","journal-title":"Clin. 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