Electrochemical, resonance Raman, and surface enhanced Raman spectroscopic study of biomolecules: cytochrome c and its mutants

dc.contributor.advisor Therese M. Cotton
dc.contributor.author Zhou, Chengli
dc.contributor.department Chemistry
dc.date 2018-08-23T03:38:00.000
dc.date.accessioned 2020-06-30T07:12:13Z
dc.date.available 2020-06-30T07:12:13Z
dc.date.copyright Mon Jan 01 00:00:00 UTC 1996
dc.date.issued 1996
dc.description.abstract <p>In this work, conventional electrochemical methods were coupled with structure sensitive techniques, resonance Raman and surface-enhanced resonance Raman spectroscopies to study the electrochemical behavior, electron transfer mechanisms and configuration of the cytochrome c at modified metal electrode surfaces. Four studies were undertaken. The first one reevaluated two promoters which were studied by other research groups and a new electrode modification procedure was used. It was determined that both 2,2'-bipyridine and pyrazine act as promoters. The strengths of adsorption were found to be a very important factor which affects the promoter performance. A new idea about the structure requirement of the promoter was proposed. The second study found that thiophene, carbazole and pyridine whose molecules contain only one functional group, are all effective promoters which supported the previously proposed idea in the first study. The crucial role of these three promoters may be prevent denaturation and/or irreversible adsorption of cytochrome c or the deaminated and oligomeric components, which results in irreversible electrochemistry. In the third study, Quasi-reversible and direct electron transfer was observed between an iodide-modified gold electrode and cytochrome c. The results suggest that an electrostatic interaction between cytochrome c and the iodide-modified electrode surface plays an important role in the electrochemical response. Results obtained by surface enhanced resonance Raman scattering (SERRS) spectroscopy indicate that the heme group of the adsorbed cytochrome c is in the native low spin, six coordinate configuration at the iodide-modified Ag electrode, whereas at the bare Ag electrode a mixture of both low spin, six coordinate and high spin, five coordinate heme is present on the surface. In the forth study, several cytochrome c mutants were characterized by using cyclic voltammetry, resonance Raman and surface-enhanced resonance Raman spectroscopies to investigate how the mutations affect the redox potential, electron transfer kinetics and the stability of cytochrome. The results show that the mutations for the water mutants decrease the redox potentials which indicates that the mutation increases the stability of the protein. The RR results indicate that the heme environment is strongly perturbed by the mutation.</p>
dc.format.mimetype application/pdf
dc.identifier archive/lib.dr.iastate.edu/rtd/11352/
dc.identifier.articleid 12351
dc.identifier.contextkey 6453667
dc.identifier.doi https://doi.org/10.31274/rtd-180813-10398
dc.identifier.s3bucket isulib-bepress-aws-west
dc.identifier.submissionpath rtd/11352
dc.identifier.uri https://dr.lib.iastate.edu/handle/20.500.12876/64600
dc.language.iso en
dc.source.bitstream archive/lib.dr.iastate.edu/rtd/11352/r_9626081.pdf|||Fri Jan 14 18:48:14 UTC 2022
dc.subject.disciplines Analytical Chemistry
dc.subject.keywords Chemistry
dc.subject.keywords Analytic
dc.subject.keywords Chemistry
dc.subject.keywords Analytical chemistry
dc.title Electrochemical, resonance Raman, and surface enhanced Raman spectroscopic study of biomolecules: cytochrome c and its mutants
dc.type article
dc.type.genre dissertation
dspace.entity.type Publication
relation.isOrgUnitOfPublication 42864f6e-7a3d-4be3-8b5a-0ae3c3830a11
thesis.degree.level dissertation
thesis.degree.name Doctor of Philosophy
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