| Publication Type |
Journal Article |
| Title |
Mediated catalysis of Paracoccus pantotrophus cytochrome c peroxidase by P-pantotrophus pseudoazurin: kinetics of intermolecular electron transfer |
| Authors |
P. M. Paes de Sousa S. R. Pauleta M. L. Simoes Goncalves G. W. Pettigrew Jose J. G. Moura Margarida Correia dos Santos |
| Groups |
|
| Journal |
JOURNAL OF BIOLOGICAL INORGANIC CHEMISTRY |
| Year |
2007 |
| Month |
June |
| Volume |
12 |
| Number |
5 |
| Pages |
691-698 |
| Abstract |
This work reports the direct electrochemistry of Paracoccus pantotrophus pseudoazurin and the mediated catalysis of cytochrome c peroxidase from the same organism. The voltammetric behaviour was examined at a gold membrane electrode, and the studies were performed in the presence of calcium to enable the peroxidase activation. A formal reduction potential, E (0) , of 230 +/- 5 mV was determined for pseudoazurin at pH 7.0. Its voltammetric signal presented a pH dependence, defined by pK values of 6.5 and 10.5 in the oxidised state and 7.2 in the reduced state, and was constant up to 1 M NaCl. This small copper protein was shown to be competent as an electron donor to cytochrome c peroxidase and the kinetics of intermolecular electron transfer was analysed. A second-order rate constant of 1.4 +/- 0.2 x 10(5) M(-1) s(-1) was determined at 0 M NaCl. This parameter has a maximum at 0.3 M NaCl and is pH-independent between pH 5 and 9. |
| DOI |
http://dx.doi.org/10.1007/s00775-007-0219-9 |
| ISBN |
|
| Publisher |
SPRINGER |
| Book Title |
|
| ISSN |
0949-8257 |
| EISSN |
|
| Conference Name |
|
| Bibtex ID |
ISI:000247482600010 |
| Observations |
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