Electrochemical properties of the interaction between cytochrome c and a hematite nanowire array electrode
Journal Article
·
· Bioelectrochemistry
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
We investigate the interaction of horse heart cytochrome c (cyt c) with hematite nanowire array electrodes by cyclic voltammetry to study the electron transfer between redox active proteins and mineral surfaces. Using this model system, we quantify electron transfer rates between cyt c and hematite under varying electric potential and pH conditions. The results are consistent with two cyt c conformations adsorbed at the hematite surface: the native and a partially unfolded form. The partially unfolded protein maintained redox activity, but at a lower redox potential than the native protein. Adsorption of cyt c allowed direct electron transfer between cyt c and hematite, with an interfacial electron transfer rate, k°ET, of 0.4 s-1 for the native form and 0.55 s-1 for the partially unfolded protein at pH 7.07. At pH 4.66, protein adsorption decreased compared to neutral pH and the fraction of partially unfolded protein increased. Additionally, the diffusion controlled electron transfer rate between hematite and the electron shuttling compound anthraquinone-2,6-disulfonate (AQDS) was determined to be k°ET = 8.0·10-3 cm·s-1 at pH 7.07. In conclusion, modulation of electron transfer rates as a result of conformational changes by redox active proteins has broad implications for describing chemical transformations at biological-mineral interfaces.
- Research Organization:
- Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
- Sponsoring Organization:
- USDOE
- Grant/Contract Number:
- AC05-00OR22725
- OSTI ID:
- 1530101
- Alternate ID(s):
- OSTI ID: 1703959
- Journal Information:
- Bioelectrochemistry, Journal Name: Bioelectrochemistry Journal Issue: C Vol. 129; ISSN 1567-5394
- Publisher:
- ElsevierCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Similar Records
Structural and redox properties of mitochondrial cytochrome c co-sorbed with phosphate on hematite (α-Fe2O3) surfaces
Redox-linked conformation change and electron transfer between monoheme c-type cytochromes and oxides
Cryo-EM structures of engineered active bc1-cbb3 type CIII2CIV super-complexes and electronic communication between the complexes
Journal Article
·
Tue Aug 01 00:00:00 EDT 2006
· Journal of Colloid and Interface Science, 303(2):404-414
·
OSTI ID:944782
Redox-linked conformation change and electron transfer between monoheme c-type cytochromes and oxides
Journal Article
·
Thu Jun 15 00:00:00 EDT 2006
· Geochimica et Cosmochimica Acta, 70(17):4332-4342
·
OSTI ID:944781
Cryo-EM structures of engineered active bc1-cbb3 type CIII2CIV super-complexes and electronic communication between the complexes
Journal Article
·
Tue Feb 09 19:00:00 EST 2021
· Nature Communications
·
OSTI ID:1816760