Melittin Stimulates Incorporation and Degradation of Sphingomyelin in Synaptosomal Plasma Membranes |
| |
| Authors: | R Pellkofer D Marsh P Hoffmann-Bleihauer K Sandhoff |
| |
| Institution: | Institut für Organische Chemie und Biochemie der Universität Bonn, F.R.G.;Max-Plunck-Institut fur hiophysikalische Chemie, Güttingen, F.R.G. |
| |
| Abstract: | Abstract: Melittin enhanced sphingomyelin (SPM) degradation by the neutral membrane-bound sphingomyelinase from calf brain synaptosomal plasma membranes (SYM) up to 20-fold. Melittin in concentrations as high as 100 μM did not significantly alter membrane fluidity of SYM as measured by fluorescence depolarization and electron spin resonance (ESR) using diphenylhexatriene and a doxy1 derivative of SPM, respectively. In the concentration range 100-1000 μM. melittin was observed to rigidify SYM. The incorporation of SPM.erivatives into the lipid bilayer of SYM.as demonstrated by ESR measurements. Melittin enhanced the uptake of SPM-derivatives into SYM. |
| |
| Keywords: | Membrane-bound neutral sphingomyelinase Synaptosomal plasma membranes Melittin Fluorescence depolarization Electron spin resonance Sphingomyelin spin label |
|
