Anti-Biofilm Effects of Synthetic Antimicrobial Peptides Against Drug-Resistant Pseudomonas aeruginosa and Staphylococcus aureus Planktonic Cells and Biofilm.

Seong-Cheol Park,Jin-Young Kim,Hyeonseok Kim,Myunghwan Jung,Woo-Kon Lee,Jung Ro Lee,Gang-Won Cheong,Mi-Kyeong Jang,Min-Young Lee,Min-Kyoung Shin

doi:10.3390/molecules24244560

Abstract

Biofilm-associated infections are difficult to manage or treat as biofilms or biofilm-embedded bacteria are difficult to eradicate. Antimicrobial peptides have gained increasing attention as a possible alternative to conventional drugs to combat drug-resistant microorganisms because they inhibit the growth of planktonic bacteria by disrupting the cytoplasmic membrane. The current study investigated the effects of synthetic peptides (PS1-2, PS1-5, and PS1-6) and conventional antibiotics on the growth, biofilm formation, and biofilm reduction of drug-resistant Pseudomonas aeruginosa and Staphylococcus aureus. The effects of PS1-2, PS1-5, and PS1-6 were also tested in vivo using a mouse model. All peptides inhibited planktonic cell growth and biofilm formation in a dose-dependent manner. They also reduced preformed biofilm masses by removing the carbohydrates, extracellular DNA, and lipids that comprised extracellular polymeric substances (EPSs) but did not affect proteins. In vivo, PS1-2 showed the greatest efficacy against preformed biofilms with no cytotoxicity. Our findings indicate that the PS1-2 peptide has potential as a next-generation therapeutic drug to overcome multidrug resistance and to regulate inflammatory response in biofilm-associated infections.

Highlights

Biofilm consists of microorganisms embedded in a self-produced matrix of extracellular polymeric substances (EPSs) containing polysaccharides, extracellular DNA, proteins, and lipids [1,2,3].The emergence of multidrug-resistant microorganisms in clinical therapeutics is a global healthcare concern
Antimicrobial peptides (AMPs) have gained increasing attention as a possible alternative to conventional drugs to combat drug-resistant microorganisms because they inhibit the growth of planktonic bacteria by disrupting the cytoplasmic membrane and inhibiting intracellular macromolecules
These results indicate that AMPs can prevent the proliferation of both drug-resistant and drug-susceptible bacteria owing to their quick and efficient bactericidal mechanisms

Summary

Introduction

Biofilm consists of microorganisms embedded in a self-produced matrix of extracellular polymeric substances (EPSs) containing polysaccharides, extracellular DNA, proteins, and lipids [1,2,3].The emergence of multidrug-resistant microorganisms in clinical therapeutics is a global healthcare concern. The National Institutes of Health in the USA reported that approximately 80% of chronic. Infectious processes in biofilm are divided into two types, namely device- and non-device-associated infections [5]. Device-associated infections are caused by microbial colonization of medical devices such as urinary catheters, bone joints, heart valves, dental implants, prostheses, contact lenses, and endotracheal tubes [5,6,7,8,9,10]. The occurrence of nosocomial infections through biomaterials or implants is approximately 60–70%; of those, 720,000 cases of central line-associated bloodstream infections occur annually in the USA via dialysis and intensive care units with an associated 12% mortality and a $45,000 increase in treatment cost per episode [11]

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Conclusion