DFT Protocol for EPR prediction of paramagnetic Cu(II) complexes and application to protein binding sites

With the aim to provide a general protocol to interpret electron paramagnetic resonance (EPR) spectra of paramagnetic copper(II) coordination compounds, density functional theory (DFT) calculations of spin Hamiltonian parameters g and A for fourteen Cu(II) complexes with different charges, donor set...

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Detalles Bibliográficos
Autores: Sciortino, Giuseppe|||0000-0001-9657-1788, Lubinu, Giuseppe|||0000-0002-9526-7749, Maréchal, Jean-Didier|||0000-0002-8344-9043, Garribba, Eugenio|||0000-0002-7229-5966
Tipo de recurso: artículo
Fecha de publicación:2018
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:216910
Acceso en línea:https://ddd.uab.cat/record/216910
https://dx.doi.org/urn:doi:10.3390/magnetochemistry4040055
Access Level:acceso abierto
Palabra clave:Copper
EPR spectroscopy
DFT methods
Human serum albumin
Prion protein
Descripción
Sumario:With the aim to provide a general protocol to interpret electron paramagnetic resonance (EPR) spectra of paramagnetic copper(II) coordination compounds, density functional theory (DFT) calculations of spin Hamiltonian parameters g and A for fourteen Cu(II) complexes with different charges, donor sets, and geometry were carried out using ORCA software. The performance of eleven functionals was tested, and on the basis of the mean absolute percent deviation (MAPD) and standard deviation (SD), the ranking of the functionals for Az is: B3LYP > B3PW91 ~ B3P86 > PBE0 > CAM-B3LYP > TPSSh > BH and HLYP > B2PLYP > MPW1PW91 > ω-B97x-D » M06; and for gz is: PBE0 > BH and HLYP > B2PLYP > ω-B97x-D > B3PW91~B3LYP~B3P86 > CAM-B3LYP > TPSSh~MPW1PW91 » M06. With B3LYP the MAPD with respect to A exp tl z is 8.6% with a SD of 4.2%, while with PBE0 the MAPD with respect to g exp tl z is 2.9% with a SD of 1.1%. The results of the validation confirm the fundamental role of the second order spin-orbit contribution to Az. The computational procedure was applied to predict the values of gz and Az of the adducts formed by Cu(II) with albumin and two fragments of prion protein, 106-126 and 180-193.