Hexima Ltd · ASX:HXL
Hexima — Technical Presentation (March 2022)
8 slides from Hexima's technical presentation, March 2022
Slide 1: Pezadeftide Is a Potent Antifungal Peptide with Rapid Fungicidal Activity via a Unique Mechanism of Action
PEZADEFTIDE IS A POTENT ANTIFUNGAL PEPTIDE WITH RAPID FUNGICIDAL ACTIVITY VIA A UNIQUE MECHANISM OF ACTION van der Weerden N.L.,1,2 McKenna J.,2 Parisi K.,2 Hayes B.M.,2 Bleackley M.R.,2 Aldridge M.D.,1 Welburn P.J.,1 and Anderson M.A.1,2 1Hexima Limited, La Trobe Institute for Molecular Science, La
Slide 2: Pezadeftide Is a Fungicidal Plant Defensin with Potent Activity Against Fungal Pathogens
Pezadeftide P EZAD E FT IDE IS A F UN G IC IDAL IC50 MIC P L AN T D E F E N S IN W IT H P OT E N T Fungal pathogen (μg/ml) (μg/ml) AC T IV IT Y AG AIN ST F UNG AL Microsporum canis 10214 6.3 32 • IC50 and minimum PAT H O G E N S T H AT C AUS E S K IN , inhibitory concentrations Microsporum gypseum 1
Slide 3: Pezadeftide Directly Disrupts Fungal Cell Membrane Integrity
P EZAD E FT IDE D IREC T LY D IS RUPTS F UN G AL C ELL M E MB RAN E INT EG RIT Y • Pezadeftide has a novel fungicidal mechanism of action distinct from triazole-based drugs • The direct antifungal mechanism of action of pezadeftide reflects 3 key events 1. Accumulation of pezadeftide at the cell sur
Slide 4: Pezadeftide Enters the Cell and Hyperpolarizes the Mitochondria
P EZAD E FT IDE E N T E RS T H E C ELL AN D H Y P ERP O LARIZ ES T H E M ITO C H O N DRIA Pezadeftide TMRM Merge • Binding and internalization Cell Wall Binding and Movement Into Cytoplasm of labeled pezadeftide 6 min • Pezadeftide binds and accumulates at the (green) and fluorescence of cell surfac
Slide 5: Pezadeftide Induces ROS Production and Promotes Cell Death and Permeability
P EZAD E FT IDE IN D UC ES RO S P RO D UC T IO N AN D P RO M OT ES C E L L ROS D EAT H AN D P E RM EAB ILIT Y (DHR123) Pezadeftide Merge • In T. rubrum, ROS production (green) increased in the presence ROS Production and Plasma of labeled pezadeftide (red) Membrane Permeabilization • Mitochondrial m
Slide 6: Plasma Membrane Permeabilization Methods
PLASMA MEMBRANE PERMEABILIZATION METHODS • The membrane impermeable fluorescent dye SYTOX green (Life Technologies) was added to T. rubrum cells prior to the addition of pezadeftide-TAMRA • The location of pezadeftide in T. rubrum hyphae was monitored using pezadeftide labeled with the red fluoresce
Slide 7: Mitochondrial Hyperpolarization Methods
MITOCHONDRIAL HYPERPOLARIZATION METHODS • The effect of pezadeftide on mitochondrial membrane potential was investigated with flow cytometry using TMRM, a dye that fluoresces when taken up by mitochondria • Saccharomyces cerevisiae cells were treated with 15 µM pezadeftide or 5 µM CCCP, a chemical k
Slide 8: ROS Production Methods
ROS PRODUCTION METHODS • ROS production by T. rubrum in response to pezadeftide treatment was assessed using the ROS-specific fluorescent probe, DHR123 (Life Technologies) • In the presence of ROS, DHR123 is converted to rhodamine 123, which has fluorescence excitation/emission maxima at 507/529 nm