新しい質量分析装置を用いた生体中のタンパク質即時発見と同定

抄録

We will describe a novel API-Qq-TOF mass spectrometer with ultra-high-resolution and ultra-high MS and MSMS mass accuracy at high scan speed. The resolution, speed and mass accuracy along with intra-spectra dynamic range of more than four orders of magnitude and preservation of isotopic patterns sets a new gold standard for one of the key challenges in the proteomic world – label free quantitation of complex biological samples. The comprehensive quantification of specific changes in biological systems would use labelling with dyes or isotope enriched chemicals thus generating internal standards for quantification. Unfortunately, many labelling strategies are expensive, require large amounts of sample and can introduce significant quantitation errors due to extensive sample handling steps. The label-free approach aims to compare direct mass spectrometric signals across multiple LC runs. The main advantages for label free quantitation on our novel API-Qq-TOF are a rapid, inexpensive, robust and accurate method with the added advantage that less sample is required. Potential biomarkers can then be fragmented and confidently identified using MSMS mass accuracy in the region of 1ppm. Challenging large peptides and small proteins can additionally be identified using Electron Transfer Dissociation (ETD) fragmentation and Proton Transfer Reaction (PTR) on an ultra high speed High Capacity Trap. We will demonstrate the successful application of label free quantitation on our novel API-Qq-TOF in a proteomics study of a cell culture model, Human lung carcinoma cell line A549. The treatment of these cells using TGF-beta is a model for lung fibrosis. We will compare the results between a 2D-DIGE study and our novel workflow for label free quantitation.