J. Biol. Chem., Vol. 261, Issue 18, 8243-8248, 06, 1986
The aggregation state of mellitin in lipid bilayers. An energy transfer study
A Hermetter and JR Lakowicz
We used fluorescence non-radiative energy transfer to measure the self-
association of melittin in solution and when bound to lipid bilayers.
Energy transfer occurred from the tryptophan residue of unlabeled melittin
to an N-methyl anthraniloyl residue covalently bound to a basic lysine
residue on melittin. The extent of energy transfer from tryptophan to the
label was found to increase severalfold upon the salt- induced
tetramerization of melittin. When bound to vesicles of
dimyristoyl-L-alpha-phosphatidylcholine, the extent of energy transfer was
found to be equivalent to that of monomeric melittin, irrespective of the
presence of monomeric or tetrameric melittin in the aqueous phase. We
conclude that membrane-bound melittin is monomeric.