(404e) A Generic Method for Designing Potent Antimicrobial Peptides and Determining Their Mechanism of Activity: A TB Example

As pathogenic bacteria become resistant to traditional antibiotics, alternate approaches such as designing and testing new potent selective antimicrobial peptides (AMP) are increasingly attractive. Using a combination of “database filtering” bioinformatics, protein engineering and de novo design, four AMPs were designed for specific activity against M. tuberculosis.  Here, we (i) describe the method, (ii) determine their mechanism of cell membrane disruption as a 4-stage barrel-stave pore formation using known mechanisms of natural AMPs, and (iii) demonstrate that the in vitro disruption of bacterial-membrane mimetic supported lipid bilayers correlates with AMP potency against M. tuberculosis cells using a Quartz Crystal Microbalance with Dissipation. This suggests a rapid in vitro screen for AMP efficacy.  This approach could be useful as a generic design method and predictive assay for AMPs against other pathogenic bacteria.