Molecular Dynamics and Ion Mobility Spectrometry Study of Model beta-Hairpin Peptide, Trpzip1

作者：Chen Liuxi; Shao Qiang; Gao Yi Qin; Russell David H^*

来源：Journal of Physical Chemistry A, 2011, 115(17): 4427-4435.

DOI：10.1021/jp110014j

Here, we explore the conformations of gas phase, protonated tryptophan zipper 1 (trpzip1) ions and its six derivatives by an enhanced sampling molecular dynamics, specially the integrated tempering sampling molecular dynamics simulation (ITS-MDS). The structural distributions obtained from ITS-MDS are compared with results obtained from matrix-assisted laser desorption ionization (MALDI)-ion mobility-mass spectrometry (IM-MS). The IM-MS measured collision cross-section (CCS) profiles compare well with the calculated CCS profiles obtained from ITS-MDS. Although beta-turn structures are preferred for solution phase species, the ITS-MDS and IM-MS structural analysis suggests that the gamma-turn structures are preferred for gas-phase, unsolvated trpzip1 [M + H](+) ions. In addition, the data suggests that the energy landscape of the gas phase peptide ions is sensitive to the site of protonation as well as intramolecular interactions involving the lysine side chain.

• 出版日期2011-5-5