IDBR: Type A. High-Performance Surface-induced Dissociation MS/MS

Ohio State University, The, Columbus OH

Investigators

Abstract

An award is made to Ohio State University to develop and instrument that can characterize protein complexes through improved dissociation of the complexes in mass spectrometers. Proteins in living systems can play structural roles, such as those in skin and hair; they can also play active roles such as enzymes that help with digestion, or hemoglobin that carries oxygen and carbon dioxide through the body. Cellular processes such as metabolism, cell signaling, gene expression, trafficking, cell cycle regulation, and the formation of subcellular structures are contingent upon the formation and dynamic interactions of complexes/assemblies of proteins. These protein complexes may also be bound to other biomolecules (DNA/RNA), interacting in specific ways. Because protein structure is tied to function, effective tools are needed to characterize protein-protein and protein-ligand complexes. The proposed research will result in integration of surface-induced dissociation devices into multiple types of mass spectrometers that will provide information on the structures of protein complexes important in biology. Discoveries from the project will be presented in university courses and at international, national, regional, and local workshops/ conferences on mass spectrometry and biomolecule structure and in the peer-reviewed literature. The undergraduate and graduate students and the postdoctoral associate will be trained in instrument development and will also gain collaboration skills through interactions with the private sector partners and local electronics and machine shops. Early SID adopters will serve as a direct sounding board for the success of modifications. The project is vendor- and platform-neutral, with direct inclusion of multiple private sector partners, Ardara Technologies, Waters (Q-IM-TOF, quadrupole ion mobility time of flight), Thermo (Orbitrap), and Bruker (ICR, ion cyclotron resonance), providing the project team an opportunity to present at company user meetings and an opportunity for those partners to assess the commercial value of the instrument modification. This research will develop surface-induced dissociation (SID) in high/ultra-high resolution mass spectrometers and refine its use in an ion mobility (IM) mass spectrometer whose purpose is to characterize protein complexes. The proposed research will benefit researchers from many different fields interested in the characterization of the topology of protein complexes. Planned, collaborative visits to Thermo and Bruker are a necessary part of the research, to gain familiarity with needed instrument platforms, to plan modifications, and to allow the vendors to assess progress. The final instrument configurations will combine either IM or high/ultrahigh resolving power with efficient SID fragmentation and enhanced collection of product ions. The proposed combinations are currently unavailable on any commercial instrument and are expected to enhance the quality of analysis and expand the range of biological samples that can be effectively characterized by mass spectrometry (MS). Planned improvements to SID utilize RF focusing of the ions departing the surface post collision, in contrast with the DC-only focusing that has been used in the past. Inclusion of SID in current commercial ultra-high resolution platforms has not yet been accomplished and is expected to dramatically enhance both the scope and depth of analysis on biological systems. In the Bruker instrument, the modification will allow SID to be explored, not only as a possible additional activation method, but as a replacement for collision-induced dissociation (CID). The overall intellectual merit of the project is adaptation of high performance mass spectrometers to include a higher performance activation method for fragmentation of refractory analytes, for which existing methods fail to provide direct substructure information.