DIRECT ELECTROCHEMISTRY OF REDOX PROTEINS AT PYROLYTIC-GRAPHITE ELECTRODES

Journal article

The direct (unmediated) electrochemistry of several redox proteins at pyrolytic graphite electrodes has been studied by square-wave voltammetry. For rubredoxin and the 2 left bracket 4Fe-4S right bracket ferrodoxin from Clostridium pasteurianum and flavodoxin from Megasphaera elsdenii rapid heterogeneous electron transfer is promoted by multivalent cations such as Mg**2** plus and Cr(NH//3)//6**3** plus . These proteins carry an excess of negatively charged residues, and it is suggested that their approach to the electrode surface is assisted by the high positive charge density in or near the outer Helmholtz plane that may be generated by multivalent cations. In addition, specific protein-cation association may be important. For azurin from Pseudomonas aerguginosa, direct electrochemistry is observable without the requirement of cation promoters.

Authors: Armstrong, F; Hill, H; Oliver, B; Walton, N

• Publication status: Published
• Journal: JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
• Volume: 106
• Issue: 4
• Pages: 921-923
• Publication date: 1984-01-01
• DOI: 10.1021/ja00316a015
• ISSN: 0002-7863
• Language: English