title: Mass spectrometry-based proteomics using Q Exactive, a high-performance benchtop quadrupole Orbitrap mass spectrometer.
abstract: Mass spectrometry-based proteomics has greatly benefitted from enormous advances in high resolution instrumentation in recent years. In particular, the combination of a linear ion trap with the Orbitrap analyzer has proven to be a popular instrument configuration. Complementing this hybrid trap-trap instrument, as well as the standalone Orbitrap analyzer termed Exactive, we here present coupling of a quadrupole mass filter to an Orbitrap analyzer. This "Q Exactive" instrument features high ion currents because of an S-lens, and fast high-energy collision-induced dissociation peptide fragmentation because of parallel filling and detection modes. The image current from the detector is processed by an "enhanced Fourier Transformation" algorithm, doubling mass spectrometric resolution. Together with almost instantaneous isolation and fragmentation, the instrument achieves overall cycle times of 1 s for a top 10 higher energy collisional dissociation method. More than 2500 proteins can be identified in standard 90-min gradients of tryptic digests of mammalian cell lysate- a significant improvement over previous Orbitrap mass spectrometers. Furthermore, the quadrupole Orbitrap analyzer combination enables multiplexed operation at the MS and tandem MS levels. This is demonstrated in a multiplexed single ion monitoring mode, in which the quadrupole rapidly switches among different narrow mass ranges that are analyzed in a single composite MS spectrum. Similarly, the quadrupole allows fragmentation of different precursor masses in rapid succession, followed by joint analysis of the higher energy collisional dissociation fragment ions in the Orbitrap analyzer. High performance in a robust benchtop format together with the ability to perform complex multiplexed scan modes make the Q Exactive an exciting new instrument for the proteomics and general analytical communities.
authors.affiliation: Department of Proteomics and Signal Transduction, Max-Planck Institute for Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany.
authors.forename: Annette
authors.initials: A
authors.lastname: Michalski
authors.forename: Eugen
authors.initials: E
authors.lastname: Damoc
authors.forename: Jan-Peter
authors.initials: JP
authors.lastname: Hauschild
authors.forename: Oliver
authors.initials: O
authors.lastname: Lange
authors.forename: Andreas
authors.initials: A
authors.lastname: Wieghaus
authors.forename: Alexander
authors.initials: A
authors.lastname: Makarov
authors.forename: Nagarjuna
authors.initials: N
authors.lastname: Nagaraj
authors.forename: Juergen
authors.initials: J
authors.lastname: Cox
authors.forename: Matthias
authors.initials: M
authors.lastname: Mann
authors.forename: Stevan
authors.initials: S
authors.lastname: Horning
mesh_terms: D000465:Algorithms; D000595:Amino Acid Sequence; D005260:Female; D006367:HeLa Cells; D006801:Humans; D007477:Ions; D013058:Mass Spectrometry / Q000295:instrumentation / Q000379:methods; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000032:analysis* / Q000737:chemistry; D011506:Proteins / Q000032:analysis* / Q000737:chemistry; D040901:Proteomics / Q000379:methods*
chemical_list: D007477:Ions; D010446:Peptide Fragments; D011506:Proteins