Isolation and Purification of Superoxide-Producing Protein Complex from Helianthus tuberosus, Daucus sativus, and Solanum tuberosum Download PDF

In this study, isoforms of NPC-Fe(III) complexes were isolated and purified from Armenian Helianthus tuberosus, Solanum tuberosum, and Daucus sativus. The physicochemical properties of these complexes were determined for the first time, including specific amounts, О₂^--producing activity, stationary concentration of О₂^-, and fluorescence intensity. The complexes exhibit maximal optical absorptions in the visible and UV regions. Hybrid associates between the isolated NPC-Fe(III) complexes and NADPH oxidase (Nox) were formed, and the production of О₂^- by these hybrid associates was observed. The complexes continuously produce О₂^- in aerobic conditions by utilizing electrons from NPC, transferring them to Fe(III), and subsequently reducing О₂ to О₂^-. Finally, О₂ stabilizes О₂^-.

Overall, these results suggest that the isoforms of NPC-Fe(III) complexes represent new prooxidant components in the aforementioned sources and that NPC serves as a bioelectric  source for the production of О₂^-.