Poster Presentation 11th Australian Peptide Conference 2015

The interaction of proline-rich antimicrobial peptides with E. coli/model membrane     (#172)

Li Wen Yi 1 2 , Sani Marc-Antoine 1 3 , Jamasbi Elaheh 1 3 , Otvos Laszlo 4 , Hossain Akhter 1 2 , O’Brien-Simpson Neil 3 5 , Separovic Frances 1 3 , Wade John 1 2
  1. School of Chemistry, University of Melbourne, Parkville, VIC, Australia
  2. The Florey Institute of Neuroscience and Mental Health, Melbourne, VIC, Australia
  3. Bio21 Institute, University of Melbourne, Melbourne, VIC, Australia
  4. Department of Biology, Temple University, Philadelphia, PA, USA
  5. Oral Health CRC, Melbourne Dental School, University of Melbourne, Melbourne, VIC, Australia

The major concern caused by pathogens bearing increasingly resistant to multi-antibiotics has motivated researchers to develop new antibiotics, including antimicrobial peptides (AMPs) 1. Due to their unique biological features, which included stimulating macrophages, the proline-rich AMPs (PrAMPs) family has been extensively studied as potential agents for the production of a new generation of antibiotics 2,3.

We undertook to better understand the mode of interaction of the de novo designed PrAMP, Chex1-Arg20, and its discontinuous dimer, A3-APO with Gram-negative E. coli membrane/model membrane interaction and their permeability. For comparison, a disulfide dimer of A3-APO was also examined [3]. We showed by high resolution microscopy and flow cytometry that there was an alteration of mechanism of antibacterial action on Gram-negative E. coli membrane/model membrane of a designed proline-rich antimicrobial peptide (PrAMP), Chex1-Arg20, with increasing valency from monomer to dimer and tetramer. Furthermore, Chex1-Arg20 and multimers displayed differences in E. coli membrane/model membrane potential. Such altered properties of these multimers advance on understanding of this type of AMP and suggest significant potential for the further development of novel PrAMPs.    

  1. M. S. Butler, J Antibiot 2013, 66, 571.
  2. W. Li, Amino Acids. 2014, 46, 2287
  3. W. Li, Aust J Chem. 2015, in press.
  4. W. Li, (submitted). 2015.