Interaction of the MARCKS peptide with PIP2 in phospholipid monolayers.
In this present work we have studied the effect of MARCKS (151-175) peptide on a mixed DPPC/PIP2 monolayer. By means of film balance, fluorescence microscopy, x-ray reflection/diffraction and neutron reflection measurements we detected changes in the lateral organization of the monolayer and changes in the perpendicular orientation of the PIP2 molecules depending on the presence of MARCKS (151-175) peptide in the subphase. In the mixed monolayer, the PIP2 molecules are distributed uniformly in the disordered phase of the monolayer, whereas the PI(4,5) groups elongate up to 10 A below the phosphodiester groups. This elongation forms the precondition for the electrostatic interaction of the MARCKS peptide with the PIP2 molecules. Due to the enrichment of PIP2 in the disordered phase, the interaction with the peptide occurs primarily in this phase, causing the PI(4,5) groups to tilt toward the monolayer interface.
Division of Soft Matter Physics, Faculty for Physics and Earth Sciences, University of Leipzig, Linnéstr. 5, D-04103 Leipzig, Germany. dietrich@physik.uni-leipzig.de
Undine
U
Dietrich
Peter
P
Krüger
Thomas
T
Gutberlet
Josef A
JA
Käs
D008856:Microscopy, Fluorescence; D009502:Neutrons; D010446:Peptide Fragments / Q000737:chemistry*; D019269:Phosphatidylinositol 4,5-Diphosphate / Q000737:chemistry*; D010743:Phospholipids / Q000737:chemistry*; D055672:Static Electricity; D014961:X-Ray Diffraction
C483227:MARCKS-related peptide; D010446:Peptide Fragments; D019269:Phosphatidylinositol 4,5-Diphosphate; D010743:Phospholipids