[Electrogenic function of submitochondrial particles at the water-octane interphases]

Area of Science:

• Biochemistry
• Bioenergetics
• Membrane Biophysics

Context:

• Submitochondrial particles (SMP) are crucial for studying mitochondrial electron transport.
• Interfacial phenomena in biological systems are complex and not fully understood.
• Redox reactions involve the transfer of electrons and protons, impacting cellular energy production.

Purpose:

• To investigate charge transfer mechanisms at the octane-water interface catalyzed by SMP enzymes.
• To elucidate the role of electron and proton acceptors in interfacial charge movement.
• To examine the influence of respiratory chain inhibitors on these interfacial processes.

Summary:

• Enzymatic redox reactions catalyzed by SMP at the octane-water interface result in charge transfer from the aqueous to the octane phase, detected via Volta potential shifts.
• Electron acceptors like 2-N-methyl-amino-1,4-naphthoquinone facilitate negative charge transfer upon oxidation of NADH, succinate, and ascorbate, sensitive to respiratory inhibitors.
• Proton acceptors such as 2,4-DNP induce positive charge transfer coupled with NADH and succinate oxidation, with varying sensitivity to inhibitors like rotenone and antimycin.

Impact:

• Provides insights into charge translocation across biological membranes during redox processes.
• Highlights the role of interfacial enzymatic activity in bioenergetics.
• Offers a model system for studying electron and proton transfer in complex biological environments.