Issue 20, 2015

Effects of charge states, charge sites and side chain interactions on conformational preferences of a series of model peptide ions

Abstract

The effects of charge states, charge sites and side chain interactions on conformational preferences of gas-phase peptide ions are examined by ion mobility-mass spectrometry (IM-MS) and molecular dynamics (MD) simulations. Collision cross sections (CCS) of [M + 2H]2+ and [M + 3H]3+ ions for a series of model peptides, viz. Ac-(AAKAA)nY-NH2 (AKn, n = 3–5) and Ac-Y(AEAAKA)nF-NH2 (AEKn, n = 2–5) are measured by using IM-MS and compared with calculated CCS for candidate ions generated by MD simulations. The results show that charge states, charge sites and intramolecular charge solvation are important determinants of conformer preference for AKn and AEKn ions. For AKn ions, there is a strong preference for helical conformations near the N-terminus and charge-solvated conformations near the C-terminus. For [AEKn + 2H]2+ ions, conformer preferences appear to be driven by charge solvation, whereas [AEKn + 3H]3+ ions favor more extended coil-type conformations.

Graphical abstract: Effects of charge states, charge sites and side chain interactions on conformational preferences of a series of model peptide ions

Supplementary files

Article information

Article type
Paper
Submitted
27 Apr. 2015
Accepted
10 Jūn. 2015
First published
10 Jūn. 2015

Analyst, 2015,140, 6933-6944

Author version available

Effects of charge states, charge sites and side chain interactions on conformational preferences of a series of model peptide ions

C. Xiao, L. M. Pérez and D. H. Russell, Analyst, 2015, 140, 6933 DOI: 10.1039/C5AN00826C

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements