Influence of tryptophan mutation on the direct electron transfer of immobilized tobacco peroxidase
(2020) In Electrochimica Acta 351.- Abstract
A major challenge in the design of electrochemical biodevices is to achieve fast rates of electron exchange between proteins and electrodes. In this work, we show that a significant increase in the direct electron transfer rate between a graphite electrode and Tobacco Peroxidase takes place when a surface exposed leucine, located in the vicinity of the heme pocket, is replaced by tryptophan. The analysis of the Fe(III)/Fe(II) voltammetric responses of native and mutated proteins, as a function of solution pH and temperature, leads to similar values of the reduction entropy and reorganization energy, but to a higher electronic coupling in the case of the mutant. In addition, the mutated and native proteins are shown to display similar... (More)
A major challenge in the design of electrochemical biodevices is to achieve fast rates of electron exchange between proteins and electrodes. In this work, we show that a significant increase in the direct electron transfer rate between a graphite electrode and Tobacco Peroxidase takes place when a surface exposed leucine, located in the vicinity of the heme pocket, is replaced by tryptophan. The analysis of the Fe(III)/Fe(II) voltammetric responses of native and mutated proteins, as a function of solution pH and temperature, leads to similar values of the reduction entropy and reorganization energy, but to a higher electronic coupling in the case of the mutant. In addition, the mutated and native proteins are shown to display similar electrocatalytic activities to reduce hydrogen peroxide at positive potentials, indicating that the molecular structure of the heme pocket is largely unaffected by the mutation.
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- author
- Olloqui-Sariego, José Luis ; Zakharova, Galina S. ; Poloznikov, Andrey A. ; Calvente, Juan José ; Hushpulian, Dmitry M. ; Gorton, Lo LU and Andreu, Rafael
- organization
- publishing date
- 2020
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Direct electron transfer, Mutations, Tobacco peroxidase, Tryptophan
- in
- Electrochimica Acta
- volume
- 351
- article number
- 136465
- publisher
- Pergamon Press Ltd.
- external identifiers
-
- scopus:85085236336
- ISSN
- 0013-4686
- DOI
- 10.1016/j.electacta.2020.136465
- language
- English
- LU publication?
- yes
- id
- 0c13e0a1-6e7c-4256-a9a7-d216f38c0573
- date added to LUP
- 2020-06-08 15:30:24
- date last changed
- 2022-04-18 22:43:42
@article{0c13e0a1-6e7c-4256-a9a7-d216f38c0573, abstract = {{<p>A major challenge in the design of electrochemical biodevices is to achieve fast rates of electron exchange between proteins and electrodes. In this work, we show that a significant increase in the direct electron transfer rate between a graphite electrode and Tobacco Peroxidase takes place when a surface exposed leucine, located in the vicinity of the heme pocket, is replaced by tryptophan. The analysis of the Fe(III)/Fe(II) voltammetric responses of native and mutated proteins, as a function of solution pH and temperature, leads to similar values of the reduction entropy and reorganization energy, but to a higher electronic coupling in the case of the mutant. In addition, the mutated and native proteins are shown to display similar electrocatalytic activities to reduce hydrogen peroxide at positive potentials, indicating that the molecular structure of the heme pocket is largely unaffected by the mutation.</p>}}, author = {{Olloqui-Sariego, José Luis and Zakharova, Galina S. and Poloznikov, Andrey A. and Calvente, Juan José and Hushpulian, Dmitry M. and Gorton, Lo and Andreu, Rafael}}, issn = {{0013-4686}}, keywords = {{Direct electron transfer; Mutations; Tobacco peroxidase; Tryptophan}}, language = {{eng}}, publisher = {{Pergamon Press Ltd.}}, series = {{Electrochimica Acta}}, title = {{Influence of tryptophan mutation on the direct electron transfer of immobilized tobacco peroxidase}}, url = {{http://dx.doi.org/10.1016/j.electacta.2020.136465}}, doi = {{10.1016/j.electacta.2020.136465}}, volume = {{351}}, year = {{2020}}, }