Interaction between a growth-hormone releasing hexapeptide and phospholipids spread as monolayers at the air/water interface.
The interaction between a growth-hormone releasing hexapeptide and phospholipids was studied on mixed monolayers models by means of surface fluorescence. When in a monolayer this hexapeptide which contains two tryptophan molecules was observed to fluoresce. Isothermal compression experiments showed that the complex was destroyed upon compression in the case of phosphatidylethanolamine. With phosphatidylglycerol it was observed to be stable but a dramatic reversible decrease in emission was observed at high surface pressure. This is indicative of a reversible change in the organization of the peptide-phospholipid complex. These observations indicate that, in the complex, hydrophobic interactions were weak but electrostatic ones, when present, were strong enough to maintain the GHRP attached to the monolayer and not to destabilize it. The integrity of the lipid monolayer appeared not to be affected by the peptide.
Issaurat
B
B
SANOFI, Research Center, Toulouse, France.
Teissié
J
J
D055598:Chemical Phenomena; D002627:Chemistry, Physical; D013006:Growth Hormone / Q000378:metabolism; D009842:Oligopeptides; D010743:Phospholipids; D013050:Spectrometry, Fluorescence; D013499:Surface Properties; D014364:Tryptophan
D009842:Oligopeptides; D010743:Phospholipids; C041048:growth hormone releasing hexapeptide; D014364:Tryptophan; D013006:Growth Hormone