Redox potential control and applications in microaerobic and anaerobic fermentations

The effect of hydrogen bonds around the active site of Anabaena [2Fe-2S] ferredoxin (Fd) on a vertical ionization potential of the reduced state (IP(red)) is examined based on the density functional theory (DFT) calculations. The results indicate that a single hydrogen bond increases the relative stability of the reduced state, and shifts IP(red) to a reductive side by 0.31–0.33 eV, regardless of the attached sulfur atoms. In addition, the IP(red) value can be changed by the number of hydrogen bonds around the active site. The results also suggest that the redox potential of [2Fe-2S] Fd is controlled by the number of hydrogen bonds because IP(red) is considered to be a major factor in the redox potential. Furthermore, there is a possibility that the redox potentials of artificial iron-sulfur clusters can be finely controlled by the number of the hydrogen bonds attached to the sulfur atoms of the cluster.

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Redox potential control in molten salt systems for corrosion mitigation

Corrosion Science ◽

10.1016/j.corsci.2018.08.035 ◽

2018 ◽

Vol 144 ◽

pp. 44-53 ◽

Cited By ~ 24

Author(s):

Jinsuo Zhang ◽

Charles W. Forsberg ◽

Michael F. Simpson ◽

Shaoqiang Guo ◽

Stephen T. Lam ◽

...

Keyword(s):

Redox Potential ◽

Molten Salt ◽

Potential Control ◽

Salt Systems

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Ab Initio Quantum Mechanical Study of Metal Substitution in Analogues of Rubredoxin: Implications for Redox Potential Control

The Journal of Physical Chemistry B ◽

10.1021/jp9912814 ◽

1999 ◽

Vol 103 (37) ◽

pp. 8006-8015 ◽

Cited By ~ 6

Author(s):

Brian W. Beck ◽

John B. Koerner ◽

Toshiko Ichiye

Keyword(s):

Redox Potential ◽

Ab Initio ◽

Quantum Mechanical ◽

Metal Substitution ◽

Potential Control ◽

Mechanical Study ◽

Quantum Mechanical Study

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Probing electrostatic interactions in cytochrome c using site-directed chemical modification

Biochemistry and Cell Biology ◽

10.1139/o01-238 ◽

2002 ◽

Vol 80 (2) ◽

pp. 197-203 ◽

Cited By ~ 2

Author(s):

Christian Blouin ◽

J Guy Guillemette ◽

Carmichael JA Wallace

Keyword(s):

Cytochrome C ◽

Chemical Modification ◽

Redox Potential ◽

Protein Interactions ◽

Electrostatic Interactions ◽

Heme Iron ◽

Dielectric Constants ◽

Protein Protein Interactions ◽

Potential Control ◽

Electrostatic Probe

This communication reports the generation of an electrostatic probe using chemical modification of methionine side chains. The alkylation of methionine by iodoacetamide was achieved in a set of Saccharomyces cerevisiae iso-1-cytochrome c mutants, introducing the nontitratable, nondelocalized positive charge of a carboxyamidomethylmethionine sulfonium (CAMMS) ion at five surface and one buried site in the protein. Changes in redox potential and its variation with temperature were used to calculate microscopic effective dielectric constants operating between the probe and the heme iron. Dielectric constants (ε) derived from ΔΔG values were not useful due to entropic effects, but εΔΔH gave results that supported the theory. The effect on biological activity of surface derivatization was interpreted in terms of proteinprotein interactions. The introduction of an electrostatic probe in cytochrome c often resulted in marked effects on activity with one of two physiological partners: cytochrome c reductase, especially if introduced at position 65, and cytochrome c oxidase, if at position 28.Key words: protein engineering, chemical modification, cytochrome c, electron transport, protein electrostatics, redox potential control.

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