Poster Presentation The 16th Australian Peptide Conference 2025

Bioengineered peptide-graphene nanoconjugates: A multifunctional strategy for broad-spectrum antimicrobial intervention (#204)

Shubhi Dr. Joshi 1 2 , Gaurav Prof. Verma 3 , Avneet Dr. Saini 4
  1. University School of Allied Health Sciences, Rayat Bahra University, Mohali, Punjab, India
  2. Panjab Univeristy, Chandigarh, CHANDIGARH, India
  3. Dr. Shanti Swarup Bhatnagar University Institute of Chemical Engineering & Technology, Panjab University, Chandigarh, India
  4. Department of Biophysics, Panjab University, Chandigarh, India

Infections mediated by bacteria can trigger multiple acute or chronic diseases. The clinical success of existing antimicrobial regimes has been severely challenged by the emergence of multidrug-resistant strains necessitating the development of alternate improved strategies with broad-spectrum bactericidal effects. Antimicrobial peptides (AMPs) are effective therapeutic alternatives to conventional antibiotics. We have designed a 15 residue novel synthetic peptide DP1 (RFGRFLRKILRFLKK) based on physiochemical properties like charge, hydrophobicity and amphipathicity. Molecular dynamics simulations and Circular dichroism spectroscopy provided valuable insight into the alpha-helical structure of the designed peptides. In-vitro antibacterial assays revealed strong antibacterial and antibiofilm activity against different microorganisms while being non-toxic and hemocompatible. In addition to this, DP1 displayed antimicrobial potential in S. aureus-induced systemic infection model. To further enhance the applicability of the novel peptide, DP1 was conjugated with graphene oxide (GO) and reduced graphene oxide (rGO) via green chemistry approach. The peptide-functionalized nanoformulations inhibited the growth of Gram-positive (Bacillus subtilisStaphylococcus aureus), Gram-negative (Escherichia coliSalmonella typhi) as well as multidrug-resistant bacterial strains (Pseudomonas aeruginosa and Methicillin-resistant Staphylococcus aureus). The biomedical applicability of this peptide based nanoformulation was observed as an antifouling nanocoating, antibacterial additive in acrylic paints and as an antipseudomonal wound dressing. Overall, we present DP1 as a multifaceted peptide with potent bactericidal and therapeutic properties. As a nanoformulation, it is a highly promising system to combat bacterial infections that are destined to find utility as surface coatings, antibacterial and antifouling additives.