{"paper":{"title":"Limitations of Classical Force Fields for Metal Coordination Modes in Proteins: A Multilevel Study of Ca$^{2+}$ in Integrin $\\alpha_V\\beta_3$","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":[],"primary_cat":"physics.chem-ph","authors_text":"Di Valentin Cristiana, Frigerio Giulia, Grollier Jules, Levy Andrea, Rothlisberger Ursula, Siani Paulo","submitted_at":"2026-06-26T13:28:22Z","abstract_excerpt":"Standard biomolecular force fields often present limitations in modeling metal coordination modes. Here, we combined classical and QM/MM molecular dynamics simulations to investigate the Ca$^{2+}$ mediated binding of cRGD to integrin $\\alpha_V\\beta_3$. The results demonstrate the inherent limitations of fixed-point-charge force fields in reproducing asymmetric binding modes and highlight the value of QM-based multilevel approaches to assess the correctness and accuracy of FF models and capture metal coordination modes in complex biomolecular systems."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2606.28463","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2606.28463/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}