Site of fluorescent label modifies interaction of melittin with live cells and model membranes
Elaheh Jamasbi, Giuseppe D Ciccotosto, Julien Tailhades, Roy M Robins-Browne, Cathryn L Ugalde, Robyn A Sharples, Nitin Patil, John D Wade, Mohammed Akhter Hossain, Frances Separovic
BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES | ELSEVIER SCIENCE BV | Published : 2015
The mechanism of membrane disruption by melittin (MLT) of giant unilamellar vesicles (GUVs) and live cells was studied using fluorescence microscopy and two fluorescent synthetic analogues of MLT. The N-terminus of one of these was acylated with thiopropionic acid to enable labeling with maleimido-AlexaFluor 430 to study the interaction of MLT with live cells. It was compared with a second analogue labeled at P14C. The results indicated that the fluorescent peptides adhered to the membrane bilayer of phosphatidylcholine GUVs and inserted into the plasma membrane of HeLa cells. Fluorescence and light microscopy revealed changes in cell morphology after exposure to MLT peptides and showed bleb..View full abstract
The authors are grateful to the University of Melbourne for award of MNI Interdisciplinary Seed Funding to JC, MAH and FS. We also thank Prof. Leann Tilley for use of the DV microscope. EJ is the recipient of a Melbourne International Research Scholarship. Research at the Florey Institute of Neuroscience and Mental Health and the Murdoch Childrens Research Institute is supported by the Victorian Government Operational Infrastructure Support Program.