Standardization of Hydroxyl Radical Protein Footprinting Data Using a Radical Dosimeter in High Resolution Footprinting of Lysozyme

摘要

Hydroxyl radical protein footprinting (HRPF) coupled with mass spectrometry is a powerful tool used to probe protein structure, interactions and conformational changes in solution phase. Recent validation of ETD providing accurate and reliable oxidation quantification at the residue level for isomeric mixtures enables an accurate and high spatial resolution HRPF. In order to obtain a more robust HRPF data, a radical dosimeter can be introduced to monitor the hydroxyl radicals diffused into each sample and to compare the HRFP data from sample to sample. In our lab, we test the ability to use adenine as the radical dosimeter to study the relationship between adenine oxidation and lysozyme oxidation at both peptide level and residual level, using HRPF combined with ETD fragmentation method.