Halictine-1 (Hal-1) – a linear antibacterial dodecapeptide isolated from the venom of the eusocial bee Halictus sexcinctus – has been subjected to a detailed spectroscopic study including circular dichroism, fluorescence and vibrational spectroscopy. We investigated Hal-1's ability to adopt an amphipathic α-helical structure upon interaction with model lipid based bacterial membranes (phosphatidylcholine/phosphatidylglycerol based large unilamellar vesicles, sodium dodecylsulfate micelles) and helix inducing components (trifluoroethanol). It was found that Hal-1 responds sensitively to composition of the membrane model and to peptide/lipid ratio. Amphipathic nature of the helical Hal-1 seems to favour flat charged surfaces of the model lipid particles over the non-directional interaction with trifluoroethanol. Increasing fraction of polyproline II type conformation was detected at low peptide/lipid ratios.
IOS Press, Inc.
6751 Tepper Drive
Clifton, VA 20124
Tel.: +1 703 830 6300
Fax: +1 703 830 2300 firstname.lastname@example.org
(Corporate matters and books only) IOS Press c/o Accucoms US, Inc.
For North America Sales and Customer Service
West Point Commons
Lansdale PA 19446
Tel.: +1 866 855 8967
Fax: +1 215 660 5042 email@example.com