{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,24]],"date-time":"2025-10-24T01:00:08Z","timestamp":1761267608172,"version":"build-2065373602"},"reference-count":108,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2025,10,23]],"date-time":"2025-10-23T00:00:00Z","timestamp":1761177600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>The SARS-CoV-2 pandemic has driven the emergence of many viral variants carrying multiple mutations, particularly in the spike glycoprotein, which enhance viral adaptability and may alter the structure and functionality of the protein. Here, we present, to the best of our knowledge, the first systematic and comparative structural analysis of monomeric spike protein subunit 1 from three distinct SARS-CoV-2 variants at physiological pH (7.4). A multimodal approach was employed, integrating experimental techniques, including Attenuated Total Reflection Infrared and circular dichroism spectroscopies, with computational methods such as molecular dynamics simulations and surface polarity analyses. This combined approach allowed us to characterize the secondary structure composition, three-dimensional conformational organization, and solvent interaction profiles of each variant. Our findings reveal how the structural and functional properties of the spike protein subunit 1 are influenced by specific amino acid mutations. Indeed, the observed conformational changes and variations in solvent interactions have significant implications for viral infectivity and immune evasion. These findings contribute to the broader understanding of the evolution of SARS-CoV-2 variants and offer valuable insights for drug development, targeted prevention strategies, and biosensor design.<\/jats:p>","DOI":"10.3390\/ijms262110342","type":"journal-article","created":{"date-parts":[[2025,10,24]],"date-time":"2025-10-24T00:47:36Z","timestamp":1761266856000},"page":"10342","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Multimodal Structural Characterization of SARS-CoV-2 Spike Variants: Spectroscopic and Computational Insights"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4399-3869","authenticated-orcid":false,"given":"Tiziana","family":"Mancini","sequence":"first","affiliation":[{"name":"Department of Physics, University La Sapienza, P.le A. Moro 2, 00185 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4438-5902","authenticated-orcid":false,"given":"Nicole","family":"Luchetti","sequence":"additional","affiliation":[{"name":"Engineering Department, Universit\u00e0 Campus Bio-Medico di Roma, Via Alvaro del Portillo 21, 00128 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2360-2920","authenticated-orcid":false,"given":"Salvatore","family":"Macis","sequence":"additional","affiliation":[{"name":"Department of Physics, University La Sapienza, P.le A. Moro 2, 00185 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9851-9932","authenticated-orcid":false,"given":"Velia","family":"Minicozzi","sequence":"additional","affiliation":[{"name":"Department of Physics, University of Rome Tor Vergata, Via della Ricerca Scientifica 1, 00133 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6768-3967","authenticated-orcid":false,"given":"Rosanna","family":"Mosetti","sequence":"additional","affiliation":[{"name":"Department of Basic and Applied Sciences for Engineering (SBAI), Sapienza University of Rome, Via A. Scarpa 16, 00161 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7088-4820","authenticated-orcid":false,"given":"Alessandro","family":"Nucara","sequence":"additional","affiliation":[{"name":"Department of Physics, University La Sapienza, P.le A. Moro 2, 00185 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Stefano","family":"Lupi","sequence":"additional","affiliation":[{"name":"Department of Physics, University La Sapienza, P.le A. Moro 2, 00185 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7990-5117","authenticated-orcid":false,"given":"Annalisa","family":"D\u2019Arco","sequence":"additional","affiliation":[{"name":"Department of Physics, University La Sapienza, P.le A. Moro 2, 00185 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,23]]},"reference":[{"key":"ref_1","unstructured":"(2025, April 09). 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