Abstract

In order to investigate the functional and structural properties of cationic α-helical peptides in two different membranes, we studied the 20-residue peptide maximin H6 in two membrane-mimetic systems by NMR spectroscopy using partially 15N-labeled peptide and paramagnetic relaxation enhancements. Maximin H6, which is found in skin secretions of frogs of the Bombinae family, attacks gram-negative bacteria and acts haemolytically. While the peptide spontaneously folds into similar structures in both neutral dodecylphosphocholine (DPC) and negatively charged sodium dodecyl sulphate (SDS) micelles, its structure is more flexible in SDS as shown by 15N relaxation measurements. In addition, it is bound closer to the surface of the micelle and rotated by ∼70° around its helix axis in the negatively charged membrane surrogate compared to the structure in DPC. This might form the basis for peptide–peptide interactions through a GxxxG motif, which could finally lead to membrane disruption and, thus, preferential attack of negatively charged microbial cell walls.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.