Biophysical studies of membrane proteins/peptides. Interaction with ...

ABSTRACT
ABSTRACT
Biomembranes are responsible for the performance of multiple cellular functions
and the multiplicity of these tasks requires a complex chemical composition. While the
structural framework of biomembranes is the lipid bilayer, other components, notably
proteins, are present. These distinct components present different energies of
interaction, leading to heterogeneous lateral distribution in the membrane.
In this work, the interactions between the components of biomembranes in several
different systems were studied. The lateral distribution of major coat protein (mcp) of
the M13 bacteriophage was shown to be highly dependent on the lipid composition of
the membrane. A new methodology for quantification of protein-lipid selectivity was
also developed and applied with success to the mcp.
Protein-drug binding studies were performed following different approaches. To the
study of binding of a V-ATPase inhibitor to a selected transmembrane domain of the
enzyme, a reductionist approach was considered, while in the case of binding of
ciprofloxacin to OmpF, the intact protein was used.
The interaction of an N-terminal amphipatic segment of a BAR domain with
membranes was also investigated and insight was achieved on the possible role of this
segment in membrane remodelling.
Finally, the hypothesis of spontaneous clustering of phosphatidylinositol-(4,5)-
bisphophate was tested and ruled out.
KEYWORDS
Protein‐Lipid Interactions
M13 Major Coat Protein
V‐ATPase Inhibition
PI(4,5)P 2
BAR domains
FRET
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