3P-13 PDF
Analysis of charge-state distributions in ESI-MS of nucleosome core particles
Nanospray enables ionization of intact protein complexes in aqueous solutions without dissociation. Therefore, it is called "Native Mass Spectrometry (Native MS)". We applied Native MS to characterize gas-phase structure of nucleosome core particles (NCPs, ~200 kDa), the minimum structural unit to store DNA within nuclei. Three NCPs, (A) unmodified NCP, (B) NCP reconstituted after histone acetylation, and (C) acetylated NCP after reconstitution, and dinucleosome (di NCP; two NCPs linked with a linker DNA) were prepared and subjected to Native MS. It was suggested that charge-state distributions in the mass spectra correlate with the structural stability of NCPs.