{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,24]],"date-time":"2026-10-24T01:39:43Z","timestamp":1792805983040,"version":"4.5.0"},"reference-count":33,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2023,1,31]],"date-time":"2023-01-31T00:00:00Z","timestamp":1675123200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Union\u2019s Horizon 2020 Research and Innovation Programme","award":["101004806"],"award-info":[{"award-number":["101004806"]}]},{"name":"European Union\u2019s Horizon 2020 Research and Innovation Programme","award":["ANR-18-CE11-0007-01"],"award-info":[{"award-number":["ANR-18-CE11-0007-01"]}]},{"name":"European Union\u2019s Horizon 2020 Research and Innovation Programme","award":["A.P. PhD Fellowship EJD-2018-2021"],"award-info":[{"award-number":["A.P. 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PhD Fellowship EJD-2018-2021"]}],"id":[{"id":"https:\/\/ror.org\/035xkbk20","id-type":"ROR","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Site-directed spin labeling (SDSL) combined with continuous wave electron paramagnetic resonance (cw EPR) spectroscopy is a powerful technique to reveal, at the local level, the dynamics of structural transitions in proteins. Here, we consider SDSL-EPR based on the selective grafting of a nitroxide on the protein under study, followed by X-band cw EPR analysis. To extract valuable quantitative information from SDSL-EPR spectra and thus give a reliable interpretation on biological system dynamics, a numerical simulation of the spectra is required. However, regardless of the numerical tool chosen to perform such simulations, the number of parameters is often too high to provide unambiguous results. In this study, we have chosen SimLabel to perform such simulations. SimLabel is a graphical user interface (GUI) of Matlab, using some functions of Easyspin. An exhaustive review of the parameters used in this GUI has enabled to define the adjustable parameters during the simulation fitting and to fix the others prior to the simulation fitting. Among them, some are set once and for all (gy, gz) and others are determined (Az, gx) thanks to a supplementary X-band spectrum recorded on a frozen solution. Finally, we propose guidelines to perform the simulation of X-band cw-EPR spectra of nitroxide labeled proteins at room temperature, with no need of uncommon higher frequency spectrometry and with the minimal number of variable parameters.<\/jats:p>","DOI":"10.3390\/molecules28031348","type":"journal-article","created":{"date-parts":[[2023,2,1]],"date-time":"2023-02-01T01:36:59Z","timestamp":1675215419000},"page":"1348","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Guidelines for the Simulations of Nitroxide X-Band cw EPR Spectra from Site-Directed Spin Labeling Experiments Using SimLabel"],"prefix":"10.3390","volume":"28","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5999-7904","authenticated-orcid":false,"given":"Emilien","family":"Etienne","sequence":"first","affiliation":[{"name":"Aix Marseille University, CNRS (Centre National de la Recherche Scientifique), BIP (Bio\u00e9nerg\u00e9tique et Ing\u00e9nierie des Prot\u00e9ines), IMM (Institut de Microbiologie de la M\u00e9diterran\u00e9e), 13009 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2892-2168","authenticated-orcid":false,"given":"Annalisa","family":"Pierro","sequence":"additional","affiliation":[{"name":"Aix Marseille University, CNRS (Centre National de la Recherche Scientifique), BIP (Bio\u00e9nerg\u00e9tique et Ing\u00e9nierie des Prot\u00e9ines), IMM (Institut de Microbiologie de la M\u00e9diterran\u00e9e), 13009 Marseille, France"},{"name":"Department of Chemistry, Konstanz Research School Chemical Biology, University of Konstanz, Universit\u00e4tsstra\u00dfe 10, 78457 Konstanz, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ketty C.","family":"Tamburrini","sequence":"additional","affiliation":[{"name":"Aix Marseille University, CNRS (Centre National de la Recherche Scientifique), BIP (Bio\u00e9nerg\u00e9tique et Ing\u00e9nierie des Prot\u00e9ines), IMM (Institut de Microbiologie de la M\u00e9diterran\u00e9e), 13009 Marseille, France"},{"name":"Aix Marseille University, CNRS (Centre National de la Recherche Scientifique), AFMB (Architecture et Fonction des Macromol\u00e9cules Biologiques), 13009 Marseille, France"},{"name":"Aix Marseille University, INRAE (Institut National de Recherche Pour L\u2019agriculture, L\u2019alimentation et L\u2019Environnement), BBF (Biodiversit\u00e9 et Biotechnologies Fongiques), 13009 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alessio","family":"Bonucci","sequence":"additional","affiliation":[{"name":"Aix Marseille University, CNRS (Centre National de la Recherche Scientifique), BIP (Bio\u00e9nerg\u00e9tique et Ing\u00e9nierie des Prot\u00e9ines), IMM (Institut de Microbiologie de la M\u00e9diterran\u00e9e), 13009 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0883-6043","authenticated-orcid":false,"given":"Elisabetta","family":"Mileo","sequence":"additional","affiliation":[{"name":"Aix Marseille University, CNRS (Centre National de la Recherche Scientifique), BIP (Bio\u00e9nerg\u00e9tique et Ing\u00e9nierie des Prot\u00e9ines), IMM (Institut de Microbiologie de la M\u00e9diterran\u00e9e), 13009 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8576-5675","authenticated-orcid":false,"given":"Marl\u00e8ne","family":"Martinho","sequence":"additional","affiliation":[{"name":"Aix Marseille University, CNRS (Centre National de la Recherche Scientifique), BIP (Bio\u00e9nerg\u00e9tique et Ing\u00e9nierie des Prot\u00e9ines), IMM (Institut de Microbiologie de la M\u00e9diterran\u00e9e), 13009 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Val\u00e9rie","family":"Belle","sequence":"additional","affiliation":[{"name":"Aix Marseille University, CNRS (Centre National de la Recherche Scientifique), BIP (Bio\u00e9nerg\u00e9tique et Ing\u00e9nierie des Prot\u00e9ines), IMM (Institut de Microbiologie de la M\u00e9diterran\u00e9e), 13009 Marseille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"5468","DOI":"10.1039\/C6OB00473C","article-title":"Site-directed spin labeling of proteins for distance measurements in vitro and in cells","volume":"14","author":"Roser","year":"2016","journal-title":"Org. 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