title: Improving the performance of a quadrupole time-of-flight instrument for macromolecular mass spectrometry.
abstract: We modified and optimized a first generation quadrupole time-of-flight (Q-TOF) 1 to perform tandem mass spectrometry on macromolecular protein complexes. The modified instrument allows isolation and subsequent dissociation of high-mass protein complexes through collisions with argon molecules. The modifications of the Q-TOF 1 include the introduction of (1) a flow-restricting sleeve around the first hexapole ion bridge, (2) a low-frequency ion-selecting quadrupole, (3) a high-pressure hexapole collision cell, (4) high-transmission grids in the multicomponent ion lenses, and (5) a low repetition rate pusher. Using these modifications, we demonstrate the experimental isolation of ions up to 12 800 mass-to-charge units and detection of product ions up to 38 150 Da, enabling the investigation of the gas-phase stability, protein complex topology, and quaternary structure of protein complexes. Some of the data reveal a so-far unprecedented new mechanism in gas-phase dissociation of protein oligomers whereby a tetramer complex dissociates into two dimers. These data add to the current debate whether gas-phase structures of protein complexes do retain some of the structural features of the corresponding species in solution. The presented low-cost modifications on a Q-TOF 1 instrument are of interest to everyone working in the fields of macromolecular mass spectrometry and more generic structural biology.
authors.affiliation: Department of Biomolecular Mass Spectrometry, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Sorbonnelaan 16, 3584 CA Utrecht, The Netherlands.
authors.forename: Robert H H
authors.initials: RH
authors.lastname: van den Heuvel
authors.forename: Esther
authors.initials: E
authors.lastname: van Duijn
authors.forename: Hortense
authors.initials: H
authors.lastname: Mazon
authors.forename: Silvia A
authors.initials: SA
authors.lastname: Synowsky
authors.forename: Kristina
authors.initials: K
authors.lastname: Lorenzen
authors.forename: Cees
authors.initials: C
authors.lastname: Versluis
authors.forename: Stan J J
authors.initials: SJ
authors.lastname: Brouns
authors.forename: Dave
authors.initials: D
authors.lastname: Langridge
authors.forename: John
authors.initials: J
authors.lastname: van der Oost
authors.forename: John
authors.initials: J
authors.lastname: Hoyes
authors.forename: Albert J R
authors.initials: AJ
authors.lastname: Heck
mesh_terms: D000429:Alcohol Oxidoreductases / Q000737:chemistry; D018835:Chaperonin 10 / Q000737:chemistry; D018834:Chaperonin 60 / Q000737:chemistry; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D018835:Chaperonin 10; D018834:Chaperonin 60; D000429:Alcohol Oxidoreductases; C076865:vanillyl-alcohol oxidase