title: Alkaline transition of horse heart cytochrome c in the presence of ZnO nanoparticles.
abstract: The effect of zinc oxide nanoparticles (ZnO NPs) on cytochrome c (cyt c) in alkaline pH was studied with absorption spectroscopy and UV circular dichroism (CD). Spectral data from UV-vis spectroscopy and circular dichroism indicate only small changes in the native structure of the protein at neutral pH after the interaction with ZnO nanoparticles. The stability around the heme crevice of cyt c and therefore the switch of the axial ligand Met80 to Lys which occurs in conditions of higher pH was proven following the interaction of cytochrome c with ZnO nanoparticles. The formation of cyt c-ZnO NPs complex based on electrostatic attraction was accompanied by a significant increase in the apparent pKa constant of the alkaline transition of cyt c.
authors.affiliation: Department of Biochemistry, Faculty of Science, PJ Šafárik University, Šrobárova 2, 041 54 Košice, Slovakia.
authors.forename: Michaela
authors.initials: M
authors.lastname: Simšíková
authors.forename: Marián
authors.initials: M
authors.lastname: Antalík
mesh_terms: D000818:Animals; D045304:Cytochromes c / Q000737:chemistry / Q000378:metabolism*; D006736:Horses; D006863:Hydrogen-Ion Concentration; D008958:Models, Molecular; D009206:Myocardium / Q000201:enzymology*; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D055550:Protein Stability; D015034:Zinc Oxide / Q000737:chemistry / Q000378:metabolism*
chemical_list: D045304:Cytochromes c; D015034:Zinc Oxide