naa a22 4500 510738230 CHVBK 20180411083018.0 cr unu---uuuuu 180411e20130301xx s 000 0 eng 10.1007/s12127-013-0121-9 doi (NATIONALLICENCE)springer-10.1007/s12127-013-0121-9 Traveling-wave ion mobility-mass spectrometry reveals additional mechanistic details in the stabilization of protein complex ions through tuned salt additives [Elektronische Daten] [Linjie Han, Brandon Ruotolo] Ion mobility-mass spectrometry is often applied to the structural elucidation of multiprotein assemblies in cases where X-ray crystallography or NMR experiments have proved challenging. Such applications are growing steadily as we continue to probe regions of the proteome that are less-accessible to such high-resolution structural biology tools. Since ion mobility measures protein structure in the absence of bulk solvent, strategies designed to more-broadly stabilize native-like protein structures in the gas-phase would greatly enable the application of such measurements to challenging structural targets. Recently, we have begun investigating the ability of salt-based solution additives that remain bound to protein ions in the gas-phase to stabilize native-like protein structures. These experiments, which utilize collision induced unfolding and collision induced dissociation in a tandem mass spectrometry mode to measure protein stability, seek to develop a rank-order similar to the Hofmeister series that categorizes the general ability of different anions and cations to stabilize gas-phase protein structure. Here, we study magnesium chloride as a potential stabilizing additive for protein structures in vacuo, and find that the addition of this salt to solutions prior to nano-electrospray ionization dramatically enhances multiprotein complex structural stability in the gas-phase. Based on these experiments, we also refine the physical mechanism of cation-based protein complex ion stabilization by tracking the unfolding transitions experienced by cation-bound complexes. Upon comparison with unbound proteins, we find strong evidence that stabilizing cations act to tether protein complex structure. We conclude by putting the results reported here in context, and by projecting the future applications of this method. Springer-Verlag Berlin Heidelberg, 2013 Ion mobility-mass spectrometry nationallicence Structural stabilization nationallicence Multiprotein complex nationallicence Collision induced unfolding nationallicence Collision induced dissociation nationallicence Han Linjie Department of Chemistry, University of Michigan, 930 N. University Ave., 48108, Ann Arbor, MI, USA aut Ruotolo Brandon Department of Chemistry, University of Michigan, 930 N. University Ave., 48108, Ann Arbor, MI, USA aut International Journal for Ion Mobility Spectrometry Springer-Verlag 16/1(2013-03-01), 41-50 1435-6163 16:1<41 2013 16 12127 https://doi.org/10.1007/s12127-013-0121-9 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s12127-013-0121-9 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Han Linjie Department of Chemistry, University of Michigan, 930 N. University Ave., 48108, Ann Arbor, MI, USA aut NATIONALLICENCE 700 1- Ruotolo Brandon Department of Chemistry, University of Michigan, 930 N. University Ave., 48108, Ann Arbor, MI, USA aut NATIONALLICENCE 773 0- International Journal for Ion Mobility Spectrometry Springer-Verlag 16/1(2013-03-01), 41-50 1435-6163 16:1<41 2013 16 12127 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer