Lipid membrane binding of NK-lysin.

Abstract

The membrane-binding properties and pore-forming potential of the tumor-lysing and antibacterial polypeptide NK-lysin were investigated. Fluorescence quenching experiments show a drastic change of accessibility to Trp58 in solution and in association with a lipid membrane. Calcein release from large unilamellar vesicles and fluctuating conductivity observed across a planar lipid bilayer of asolectin show that NK-lysin renders lipid bilayers permeable in a transient fashion, indicating a nonspecific lipid interaction as the mechanism underlying the biological activity. FTIR experiments show the same amount and type of regular secondary structure of NK-lysin in the membrane as in aqueous solution and exclude a structural rearrangement into a set of parallel or antiparallel alpha-helices as the predominant conformation. The molecular mechanism of the membrane-destabilizing effect of NK-lysin is discussed.

• Authors: J M Ruysschaert, E Goormaghtigh, F Homblé, M Andersson, E Liepinsh, G Otting
• Journal: FEBS letters (FEBS Lett) Vol. 425 Issue 2 Pg. 341-4 (Mar 27 1998) ISSN: 0014-5793 [Print] England
• PMID: 9559676 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Anti-Infective Agents
• Lipid Bilayers
• NK-lysin
• Proteolipids
• Pulmonary Surfactants

Topics

• Anti-Infective Agents (metabolism)
• Lipid Bilayers (metabolism)
• Models, Molecular
• Proteolipids (metabolism)
• Pulmonary Surfactants (metabolism)