Identification of Rat Liver Aldehyde Oxidase Across Species by Accurate Peptide-Mass Fingerprinting and Sequence- Tagging with Fourier Transform Ion Cyclotron Resonance Mass Spectrometry

摘要

We evaluated applicability of Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) to protein identification across species. Nano-electrospray FT-ICR MS enabled acquisition of accurate mass spectra of protein digests at a picomole level sensitivity. Peptide mass maps with a ppm level accuracy were routinely obtained by spraying whole protein digests without internal mass calibrant. The accurate peptide mass maps allowed narrowing of database search-windows for peptide-mass fingerprinting and the search noise was substantially reduced.