Probing alpha-helical and beta-sheet structures of peptides at solid/liquid interfaces with SFG.
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.
Chen
Xiaoyun
X
Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA.
Wang
Jie
J
Sniadecki
Jason J
JJ
Even
Mark A
MA
Chen
Zhan
Z
D010455:Peptides / Q000737:chemistry*; D044367:Phase Transition; D017433:Protein Structure, Secondary; D013057:Spectrum Analysis
D010455:Peptides