Probing alpha-helical and beta-sheet structures of peptides at solid/liquid interfaces with SFG

Xiaoyun Chen; Jie Wang; Jason J Sniadecki; Mark A Even; Zhan Chen

doi:10.1021/la050048w

Probing alpha-helical and beta-sheet structures of peptides at solid/liquid interfaces with SFG

Langmuir. 2005 Mar 29;21(7):2662-4. doi: 10.1021/la050048w.

Authors

Xiaoyun Chen¹, Jie Wang, Jason J Sniadecki, Mark A Even, Zhan Chen

Affiliation

¹ Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA.

PMID: 15779931
DOI: 10.1021/la050048w

Abstract

We demonstrated that sum frequency generation (SFG) vibrational spectroscopy can distinguish different secondary structures of proteins or peptides adsorbed at solid/liquid interfaces. The SFG spectrum for tachyplesin I at the polystyrene (PS)/solution interface has a fingerprint peak corresponding to the B1/B3 mode of the antiparallel beta-sheet. This peak disappeared upon the addition of dithiothreitol, which can disrupt the beta-sheet structure. The SFG spectrum indicative of the MSI594 alpha-helical structure was observed at the PS/MSI594 solution interface. This research validates SFG as a powerful technique for revealing detailed secondary structures of interfacial proteins and peptides.

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

Peptides / chemistry*
Phase Transition
Protein Structure, Secondary
Spectrum Analysis

Substances

Peptides