Electrostatic immobilization of antimicrobial peptides on polyethylenimine and their antibacterial effect against Staphylococcus epidermidis

Abstract

Staphylococcus epidermidis is a gram-positive bacterium, and one of the most prevalent causes of nosocomial infections due to its strong ability to form biofilms on catheters and surgical implants. Here we explore the antimicrobial properties of Tet-124 peptides, which are part of the innate defense against different multicellular organisms in nature. Two different Tet-124 peptides were immobilized on a polyethylenimine (PEI) film to determine their impact on the antimicrobial properties: KLWWMIRRW (Tet-124), which contains only natural amino acids, and KLWWMIRRWG-(F-Br)-G (F-Br = 4-Bromophenylalanine), a modified Tet-124 sequence with the addition of an unnatural amino acid. The immobilization was obtained as a result of the electrostatic interaction between PEI amino groups and the C-terminal carboxylic groups of tryptophan and glycine amino acids of Tet-124 and Tet-124-Br peptides, respectively. The process was monitored and studied by water contact angle, Atomic Force Microscopy (AFM), X-ray Photoelectron Spectroscopy (XPS) and Quartz Crystal Microbalance with Dissipation (QCM-D) measurements. The antibacterial effect of our samples against S. epidermis was evaluated by the spread plate counting method, and cytotoxicity was tested using fibroblast cultures. Our results indicate the feasibility to immobilize electrostatically both Tet-124 peptides for biomedical applications.

Potent Antibacterial Composite Nonwovens Functionalized with Bioactive Peptides and Polymers

“…The values of contact angle of PEI and PAA layers align with the values reported in the literature. [ 53,54 ] We note that daptomycin and bacitracin also created thin layers—0.7 and 1.1 nm, respectively—indicating the formation of a monomolecular layer of agent. Conversely, polymyxin B, KRRWRIWLV‐NH 2 , PAEMA, and P(NIPAM‐ co ‐AEMA‐ co ‐GUMA) formed a thick layer.…”

Design and application of self-healable polymeric films and coatings for smart food packaging

“…When a food packaging film is designed, bonding interactions involved in film formation and repair play a principal role in determining the ultimate properties of the film generated. In general, non-covalent interactions are weaker than covalent bonds 61 , 62 . Using different dynamic non-covalent bonding interactions to replace the conventional covalent ones in film design may result in a decline in the mechanical strength of the generated film.…”

Mussel‐Inspired Recombinant Adhesive Protein‐Based Functionalization for Consistent and Effective Antimicrobial Treatment in Chronic Inflammatory Skin Diseases

“…To further validate the versatility of RAP as a plug-and-play functional incorporation platform, the feasibility of incorporating other functional peptide motifs was investigated using five different AFPs (Figure 1A and Table S2, Supporting Information). [38][39][40][41] In this study, the resulting antifungal RAPs incorporating AFPs were referred to as RFPs. All five RFPs were successfully expressed in an E. coli system, and their antifungal activities were assessed by measuring the colony-forming units (CFU) on tryptic soy agar (TSA) plates inoculated with Aspergillus niger (A. niger), a representative fungus.…”