Colloquium- “Simulations of Two Amphipathic Peptides” with Dr. Richard W. Pastor
Colloquium
April 3, 2024
3:00 PM - 4:00 PM
Location
SES 238
Calendar
Download iCal FileDr. Richard W. Pastor (National Institutes of Health)
Simulations of Two Amphipathic Peptides
This talk describes simulations of the fusion peptide (FP) domain of influenza hemagglutinin, and the antimicrobial peptide (AMP) piscidin 1 (p1). Both are amphiphilic (the motif of most membrane active peptides), yet experiments indicate that FP forms stable pores while those of p1 are metastable. Little is known experimentally about their mechanisms of pore formation. The simulations presented here show that FP monomers form stable antiparallel dimers which further aggregate, displace lipids, and nucleate pores. In contrast, p1 generates defects which are highly sensitive to area-stress. Defects in symmetric (area relaxed) bilayers do not form pores, while defects in asymmetric area-stressed bilayers do; this difference explains the time sequence of AMP addition and dye-release observed in experiments. Both FP and piscidin1 show lipid dependence that is captured by the simulations. Ongoing studies will determine the stability of pores generated by these two different peptides, and apply insights obtained to peptide design.
Date posted
Apr 3, 2024
Date updated
Apr 3, 2024