Effect of lipid peroxidation on protein conformational stability

Lipid oxidation can occur in vivo during oxidative stress and redox imbalance conditions, such as inflammation or environmental toxicity. This process generates reactive oxygen species (ROS), including the superoxide anion and hydroxyl radical within cells. Unsaturated fatty acids in tissues are particularly prone to oxidation by these ROS through non-enzymatic mechanisms. Lipid peroxidation, operating via a chain mechanism, produce a wide range of oxygenated small molecules, which significantly affects membrane organization and can modify proteins and DNA, leading to functional changes [1]. To study the effects of lipid peroxidation on the conformational stability of model proteins, BSA, HEWL, Ubiquitin, and rabbit IgG were solubilized in phosphate buffer and examined alone or in the presence of DMPG-DOPC (at a 1:1 molar ratio) small unilamellar vesicles (SUVs) at either 20°C or 40°C.