日本質量分析学会 第68回質量分析総合討論会会

演題概要

オーラルセッション

第3日 5月13日(水) 15:30~15:50 B会場(1202)

イオンモビリティ質量分析と分子シミュレーションのデータ同化によるH2A-H2B二量体の構造解析

(1産総研2横市大院生命医3京大院理)
o七種和美1,2明石知子2渕上壮太郎3

Ion mobility mass spectrometry (IM-MS) can provide the information of not only mass but also collision cross-section (CCS) of biomolecules in the native form. In our previous studies, we characterized biomolecular complexes, such as histone H2A-H2B dimer and nucleosome core particle, using IM-MS and all-atom molecular dynamic (MD) simulation. However, it is not easy to simulate structures of biomolecular complexes in the IM-MS experiment using conventional MD simulation because various processes in mass spectrometry, such as the ionization, desolvation, ion transportation, and so on, of biomolecular complexes, should be properly considered. In this study, we performed coarse-grained MD (CG-MD) simulation combined with IM-MS data using data assimilation with particle filter, to obtain an appropriate structural ensemble of H2A-H2B dimer that matches the experimental CCS distribution obtained by IM-MS. As the results of CG-MD simulation, the structural ensemble of H2A-H2B dimer gave CCS values in the range of 2130-2620 Å2. The CCS distribution obtained by IM-MS was included in this range. Now, we are trying to optimize the computational parameters to create a structural ensemble that can quantitatively reproduce experimental data.