{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,11]],"date-time":"2026-07-11T04:43:10Z","timestamp":1783744990966,"version":"3.55.0"},"reference-count":41,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2021,12,2]],"date-time":"2021-12-02T00:00:00Z","timestamp":1638403200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Regione Lazio - Lazio Innova","award":["POR FESR 2014-2020, Avviso Pubblico \u201cEMERGENZA CORONAVIRUS E OLTRE\u201d, CUP F84E21000030006"],"award-info":[{"award-number":["POR FESR 2014-2020, Avviso Pubblico \u201cEMERGENZA CORONAVIRUS E OLTRE\u201d, CUP F84E21000030006"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biomolecules"],"abstract":"<jats:p>COVID-19 is a highly infectious disease caused by a newly emerged coronavirus (SARS-CoV-2) that has rapidly progressed into a pandemic. This unprecedent emergency has stressed the significance of developing effective therapeutics to fight the current and future outbreaks. The receptor-binding domain (RBD) of the SARS-CoV-2 surface Spike protein is the main target for vaccines and represents a helpful \u201ctool\u201d to produce neutralizing antibodies or diagnostic kits. In this work, we provide a detailed characterization of the native RBD produced in three major model systems: Escherichia coli, insect and HEK-293 cells. Circular dichroism, gel filtration chromatography and thermal denaturation experiments indicated that recombinant SARS-CoV-2 RBD proteins are stable and correctly folded. In addition, their functionality and receptor-binding ability were further evaluated through ELISA, flow cytometry assays and bio-layer interferometry.<\/jats:p>","DOI":"10.3390\/biom11121812","type":"journal-article","created":{"date-parts":[[2021,12,2]],"date-time":"2021-12-02T21:19:08Z","timestamp":1638479948000},"page":"1812","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":21,"title":["The Nuts and Bolts of SARS-CoV-2 Spike Receptor-Binding Domain Heterologous Expression"],"prefix":"10.3390","volume":"11","author":[{"given":"Mariano","family":"Maffei","sequence":"first","affiliation":[{"name":"Evvivax Biotech, Via di Castel Romano 100, 00128 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4253-7493","authenticated-orcid":false,"given":"Linda Celeste","family":"Montemiglio","sequence":"additional","affiliation":[{"name":"Institute of Molecular Biology and Pathology (IBPM), National Research Council, c\/o Department of Biochemical Sciences \u201cAlessandro Rossi Fanelli\u201d, Sapienza, University of Rome, P. le Aldo Moro, 5, 00185 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0092-8186","authenticated-orcid":false,"given":"Grazia","family":"Vitagliano","sequence":"additional","affiliation":[{"name":"Takis Biotech, Via di Castel Romano 100, 00128 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luigi","family":"Fedele","sequence":"additional","affiliation":[{"name":"Takis Biotech, Via di Castel Romano 100, 00128 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shaila","family":"Sellathurai","sequence":"additional","affiliation":[{"name":"Takis Biotech, Via di Castel Romano 100, 00128 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Federica","family":"Bucci","sequence":"additional","affiliation":[{"name":"Takis Biotech, Via di Castel Romano 100, 00128 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mirco","family":"Compagnone","sequence":"additional","affiliation":[{"name":"Neomatrix Biotech, Via di Castel Romano 100, 00128 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Valerio","family":"Chiarini","sequence":"additional","affiliation":[{"name":"Takis Biotech, Via di Castel Romano 100, 00128 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7457-6895","authenticated-orcid":false,"given":"C\u00e9cile","family":"Exertier","sequence":"additional","affiliation":[{"name":"Department of Biochemical Sciences \u201cAlessandro Rossi Fanelli\u201d, Sapienza, University of Rome, P. le Aldo Moro, 5, 00185 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6946-3888","authenticated-orcid":false,"given":"Alessia","family":"Muzi","sequence":"additional","affiliation":[{"name":"Takis Biotech, Via di Castel Romano 100, 00128 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giuseppe","family":"Roscilli","sequence":"additional","affiliation":[{"name":"Evvivax Biotech, Via di Castel Romano 100, 00128 Rome, Italy"},{"name":"Takis Biotech, Via di Castel Romano 100, 00128 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Beatrice","family":"Vallone","sequence":"additional","affiliation":[{"name":"Department of Biochemical Sciences \u201cAlessandro Rossi Fanelli\u201d, Sapienza, University of Rome, P. le Aldo Moro, 5, 00185 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emanuele","family":"Marra","sequence":"additional","affiliation":[{"name":"Evvivax Biotech, Via di Castel Romano 100, 00128 Rome, Italy"},{"name":"Takis Biotech, Via di Castel Romano 100, 00128 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"105924","DOI":"10.1016\/j.ijantimicag.2020.105924","article-title":"Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and coronavirus disease-2019 (COVID-19): The epidemic and the challenges","volume":"55","author":"Lai","year":"2020","journal-title":"Int. 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