Identification and characterization of human proteoforms by top-down LC-21 tesla FT-ICR mass spectrometry

Abstract

The National High Magnetic Field Laboratory (NHMFL) recently installed a 21T FT-ICR mass spectrometer, which is part of the NHMFL FT-ICR User Facility and available to all qualified users. Here, we demonstrate top-down LC-21 T FT-ICR MS/MS of intact proteins derived from human colorectal cancer cell lysate. We identify a combined total of 684 unique protein entries observed as 3,238 unique proteoforms at a 1% false discovery rate, based on rapid, data-dependent acquisition of collision-induced and electron-transfer dissociation tandem mass spectra from 40 LC-MS/MS experiments.