Mapping free radical initiated oxidation of apo B-100 low density lipoprotein by LC-MS/MS

摘要

Oxidations of several amino acid residues in apoB-100 protein were found to be directly or indirectly induced by exposure to hydroxyl radical. The oxidized amino acid residues are likely on the exterior (accessible to the aqueous environment) of the LDL particle or directly bound to the free radical permeable lipid layer. Higher dose of hydroxyl radical resulted in unknown oxidation products and lower sequence coverage of identified segments of apoB-100 protein. Natural variants in apoB-100 protein are confirmed at amino acid level.