Guerrini, Giuditta Mehn, Dora Fumagalli, Francesco Gioria, Sabrina Pedotti, Mattia Simonelli, Luca Bianchini, Filippo Robbiani, Davide F. Varani, Luca Calzolai, Luigi 2023 Analytical ultracentrifugation (AUC) analysis shows that the SARS-CoV-2 trimeric Spike (S) protein adopts different quaternary conformations in solution. The relative abundance of the “open” and “close” conformations is temperature-dependent, and samples with different storage temperature history have different open/close distributions. Neutralizing antibodies (NAbs) targeting the S receptor binding domain (RBD) do not alter the conformer populations; by contrast, a NAb targeting a cryptic conformational epitope skews the Spike trimer toward an open conformation. The results highlight AUC, which is typically applied for molecular mass determination of biomolecules as a powerful tool for detecting functionally relevant quaternary protein conformations. application/pdf https://n2t.net/ark:/12658/srd1332081 https://susi.usi.ch/global/documents/332081 https://susi.usi.ch/documents/332081/files/Varani_2023_MDPI_ijms_Analytical Ultracentrifugation.pdf eng info:eu-repo/semantics/altIdentifier/doi/10.3390/ijms241914875 info:eu-repo/semantics/altIdentifier/ark/12658/srd1332081 info:eu-repo/semantics/openAccess CC BY International journal of molecular sciences. - 2023, vol. 24, no. 19, p. 14875 SARS-CoV-2 Spike Trimer Antibody AUC Analytical ultracentrifugation Sedimentation Conformation info:eu-repo/classification/udc/61 Analytical ultracentrifugation detects quaternary rearrangements and antibody-induced conformational selection of the SARS-CoV-2 spike trimer http://purl.org/coar/resource_type/c_6501