Comprehensive Peptide Ion Structure Studies Using Ion Mobility Techniques: Part 3. Relating Solution-Phase to Gas-Phase Structures

Journal Article · Wed Aug 15 04:00:00 EDT 2018 · Journal of the American Society for Mass Spectrometry

DOI:https://doi.org/10.1007/S13361-018-1996-9· OSTI ID:22776865

Kondalaji, Samaneh Ghassabi; Khakinejad, Mahdiar ^[1]

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1. Johns Hopkins University, Department of Biophysics (United States)

Molecular dynamics (MD) simulations have been utilized to study peptide ion conformer establishment during the electrospray process. An explicit water model is used for nanodroplets containing a model peptide and hydronium ions. Simulations are conducted at 300 K for two different peptide ion charge configurations and for droplets containing varying numbers of hydronium ions. For all conditions, modeling has been performed until production of the gas-phase ions and the resultant conformers have been compared to proposed gas-phase structures. The latter species were obtained from previous studies in which in silico candidate structures were filtered according to ion mobility and hydrogen-deuterium exchange (HDX) reactivity matches. Results from the present study present three key findings namely (1) the evidence from ion production modeling supports previous structure refinement studies based on mobility and HDX reactivity matching, (2) the modeling of the electrospray process is significantly improved by utilizing initial droplets existing below but close to the calculated Rayleigh limit, and (3) peptide ions in the nanodroplets sample significantly different conformers than those in the bulk solution due to altered physicochemical properties of the solvent. .

• OSTI ID: 22776865
• Journal Information: Journal of the American Society for Mass Spectrometry, Journal Name: Journal of the American Society for Mass Spectrometry Journal Issue: 8 Vol. 29; ISSN 1044-0305; ISSN JAMSEF
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
COMPARATIVE EVALUATIONS
DEUTERIUM
HYDROGEN
ION MOBILITY
IONIZATION
MOLECULAR DYNAMICS METHOD
OXONIUM IONS
PEPTIDES
SIMULATION
SOLUTIONS