Arcoria, Paul J.Ware, Rachel I.Makwana, Sunny V.Troya, DiegoEtzkorn, Felicia A.2022-01-142022-01-142021-12-301520-6106http://hdl.handle.net/10919/107643Collagen is the most abundant human protein, with the canonical sequence (Gly-Pro-Hyp)<i>_n</i> in its triple helix region. Cis-trans isomerization of the Xaa-Pro amide has made two of these amide bonds the target of alkene replacement: the Gly-Pro and the Pro-Hyp positions. The conformations of Gly-Pro and Pro-Pro (as a Pro-Hyp model) fluoro-, chloro-, and proteo-alkene mimic models were investigated computationally to determine whether these alkenes can stabilize the polyproline type II (PPII) conformation of collagen. Second-order Møller-Plesset (MP2) calculations with various basis sets were used to perform the conformational analyses and locate stationary points. The calculation results predict that fluoro- and chloro-alkene mimics of Gly-Pro and Pro-Pro can participate in n→π* donation to stabilize PPII conformations, yet they are poor n→π* acceptors, shifting the global minima away from PPII conformations. For the proteo-alkene mimics, the lack of significant n→π* interactions and unstable PPII-like geometries explains their known destabilization of the triple helix in collagen-like peptides.application/pdfenIn Copyright02 Physical Sciences03 Chemical Sciences09 EngineeringArticle - Refereed2022-01-14https://doi.org/10.1021/acs.jpcb.1c09180Etzkorn, Felicia [0000-0001-5850-3661]Troya, Diego [0000-0003-4971-4998]349684061520-5207