Insights into Interprotein Electron Transfer of Human Cytochrome c Variants Arranged in Multilayer Architectures by Means of an Artificial Silica Nanoparticle Matrix
| Autor: | Kai Ralf Stieger, Mario Piccioli, Paola Turano, Dennis Weber, Sven Christian Feifel, Andreas Kapp, Fred Lisdat, Marco Allegrozzi |
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| Jazyk: | angličtina |
| Rok vydání: | 2016 |
| Předmět: |
0301 basic medicine
biology 010405 organic chemistry Chemistry General Chemical Engineering Cytochrome c Analytical chemistry Context (language use) General Chemistry 01 natural sciences Redox 0104 chemical sciences lcsh:Chemistry 03 medical and health sciences Electron transfer chemistry.chemical_compound 030104 developmental biology lcsh:QD1-999 Monolayer ddc:540 Biophysics biology.protein Molecule Biosensor Heme |
| Zdroj: | ACS Omega, Vol 1, Iss 6, Pp 1058-1066 (2016) |
| Popis: | The redox behavior of proteins plays a crucial part in the design of bioelectronic systems. We have demonstrated several functional systems exploiting the electron exchange properties of the redox protein cytochrome c (cyt c) in combination with enzymes and photoactive proteins. The operation is based on an effective reaction at modified electrodes but also to a large extent on the capability of self-exchange between cyt c molecules in a surface-fixed state. In this context, different variants of human cyt c have been examined here with respect to an altered heterogeneous electron transfer (ET) rate in a monolayer on electrodes as well as an enhanced self-exchange rate while being incorporated in multilayer architectures. For this purpose, mutants of the wild-type (WT) protein have been prepared to change the chemical nature of the surface contact area near the heme edge. The structural integrity of the variants has been verified by NMR and UV–vis measurements. It is shown that the single-point mutations can significantly influence the heterogeneous ET rate at thiol-modified gold electrodes and that electroactive protein/silica nanoparticle multilayers can be constructed with all forms of human cyt c prepared. The kinetic behavior of electron exchange for the mutant proteins in comparison with that of the WT has been found altered in some multilayer arrangements. Higher self-exchange rates have been found for K79A. The results demonstrate that the position of the introduced change in the charge situation of cyt c has a profound influence on the exchange behavior. In addition, the behavior of the cyt c variants in assembled multilayers is found to be rather similar to the situation of cyt c self-exchange in solution verified by NMR. |
| Databáze: | OpenAIRE |
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