Factors That Influence Helical Preferences for Singly Charged Gas-Phase Peptide Ions: The Effects of Multiple Potential Charge-Carrying Sites
| Autor: | J. Martin Scholtz, David H. Russell, C. Nick Pace, Zhaoxiang Wu, John A. McLean, Christopher Becker, Lisa M. Pérez, Janel R. McLean |
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| Rok vydání: | 2009 |
| Předmět: |
Ions
Models Molecular chemistry.chemical_classification Spectrometry Mass Electrospray Ionization Molecular model Electrospray ionization Analytical chemistry Peptide Dielectric Mass spectrometry Article Protein Structure Secondary Surfaces Coatings and Films Ion Crystallography Protein structure chemistry Materials Chemistry Amino Acid Sequence Gases Physical and Theoretical Chemistry Peptides Peptide sequence |
| Zdroj: | The Journal of Physical Chemistry B. 114:809-816 |
| ISSN: | 1520-5207 1520-6106 |
| DOI: | 10.1021/jp9105103 |
| Popis: | Ion mobility-mass spectrometry is used to investigate the structure(s) of a series of model peptide [M + H](+) ions to better understand how intrinsic properties affect structure in low dielectric environments. The influence of peptide length, amino acid sequence, and composition on gas-phase structure is examined for a series of model peptides that have been previously studied in solution. Collision cross sections for the [M + H](+) ions of Ac-(AAKAA)(n)Y-NH(2) (n = 3-6) and Ac-Y(AEAAKA)(n)F-NH(2) (n = 2-5) are reported and correlated with candidate structures generated using molecular modeling techniques. The [M + H](+) ions of the AAKAA peptide series each exhibit a single, dominant ion mobility arrival time distribution (ATD) which correlates to partial helical structures, whereas the [M + H](+) ions of the AEAAKA ion series are composed of ATDs which correlate to charge-solvated globules (i.e., the charge is coordinated or solvated by polar peptide functional groups). These data raise numerous questions concerning intrinsic properties (amino acid sequence and composition as well as charge location) that dictate gas-phase peptide ion structure, which may reflect trends for peptide ion structure in low dielectric environments, such as transmembrane segments. |
| Databáze: | OpenAIRE |
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