The influence of gramicidin S on the thermotropic phase transition of dipalmitoylphosphatidylglycerol DPPG/GS systems: Experiment and computer model

Stan C., Cristescu C., Severcan F., Dorohoi D.

REVUE ROUMAINE DE CHIMIE, vol.49, no.9, pp.777-782, 2004 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 49 Issue: 9
  • Publication Date: 2004
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.777-782
  • Middle East Technical University Affiliated: Yes


The paper presents experimental data recorded by Fourier Tran form Infrared Spectroscopy regarding the influence of the antimicrobial peptide gramicidin (GS) concentration on the thermotropic phase transition of dipalmitoylphosphatidylglycerol (DPPG) lipid bilayer membrane in DPPG/GS systems, as reflected in the change of the bandwidth of the symmetric stretching band of CH2. The samples were investigated cyclically in a temperature range between 26.5degrees and 61.1degreesC which includes the gel to liquid crystal thermotropic phase transition. A computer model based on the influence of the GS concentration on the damping parameter of a linear oscillator modeling the CH2 symmetric stretching band is considered. The results of the computation are in good agreement with the observed behavior.