title: pH-dependent surface-enhanced resonance Raman scattering of yeast iso-1-cytochrome c adsorbed on silver nanoparticle surfaces under denaturing conditions at pH<3.
abstract: We measured the pH-induced spectral changes of yeast iso-1-cytochrome c on silver nanoparticle surfaces using surface-enhanced resonance Raman scattering (SERRS) at 457.9 nm. At a pH of 3, the Met80 ligand in yeast iso-1-cytochrome c is assumed to dissociate, leading to a marked conformational change as evidenced by the vibrational spectral shifts. The Soret band at 410 nm in the UV-Vis spectrum shifted to 396 nm at pH 3, indicating a transition from a low spin state to a high spin state from a weak interaction with a water molecule. Thus, SERRS spectroscopy can measure the pH-induced denaturalization of cyt c adsorbed on metal nanoparticle surfaces at a lower concentration with a better sensitivity than ordinary resonance Raman spectroscopy.
authors.affiliation: Department of Pharmacology, College of Veterinary Medicine, Seoul National University, Seoul, Korea.
authors.forename: So Yeong
authors.initials: SY
authors.lastname: Lee
authors.forename: Sang-Woo
authors.initials: SW
authors.lastname: Joo
authors.forename: Seonghoon
authors.initials: S
authors.lastname: Lee
authors.forename: Manho
authors.initials: M
authors.lastname: Lim
mesh_terms: D045304:Cytochromes c / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry*; D011489:Protein Denaturation; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry*; D012834:Silver / Q000737:chemistry*; D013059:Spectrum Analysis, Raman / Q000379:methods*
chemical_list: C014059:CYC1 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D012834:Silver; D045304:Cytochromes c