Natural Products That Target Virulence Factors in Antibiotic-Resistant Staphylococcus aureus

Abstract

The increase in the incidence of antibiotic-resistant Staphylococcus aureus (S. aureus) associated infections necessitates the urgent development of novel therapeutic strategies and antibacterial drugs. Antivirulence strategy is an especially compelling alternative strategy due to its low selective pressure for the development of drug resistance in bacteria. Plants and microorganisms are not only important food and medicinal resources but also serve as sources for the discovery of natural products that target bacterial virulence factors. This review discusses the mechanisms of the major virulence factors of S. aureus, including the accessory gene regulator quorum-sensing system, bacterial biofilm formation, α-hemolysin, sortase A, and staphyloxanthin. We also provide an overview of natural products isolated from plants and microorganisms with activity against the major virulence factors of S. aureus and their adjuvant effects on existing antibiotics to overcome antibiotic-resistant S. aureus. Finally, the limitations and solutions of these antivirulence compounds are discussed, which will help in the development of novel antibacterial drugs against antibiotic-resistant S. aureus.

Thymol Protects Channel Catfish from Aeromonas hydrophila Infection by Inhibiting Aerolysin Expression and Biofilm Formation

“…The introduction of antibiotics has revolutionized the treatments of infectious diseases caused by bacterial pathogens and contributed to the increase in life expectancy [24,25]. However, antimicrobial resistance has emerged due to the widespread use of antibiotics, and often leads to treatment failure [26]. Thus, anti-virulence strategies were devised by inhibiting pathogenicity or the ability to sustain an infection, instead of inhibiting or killing the bacteria [25].…”

Evaluation of Antimicrobial Activity and Anti-Quorum Sensing of Rosmarinus Methanol Extract on Pseudomonas aeruginosa

“…According to the studies, as secondary plant metabolites react with a wide range of cellular components, these compounds tend to influence a large number of cellular targets. Most extracts are believed to exert their antimicrobial activities through interaction with bacterial cell membrane processes, including electron transfer, ionic gradient, protein translocation, phosphorylation, and other enzyme-dependent reactions (26). Also, some differences in the results of these studies are related to differences in plant growth, amount of useful substances, and type of microorganism, extract, harvest season, and different methods of investigation.…”

Rosmarinus officinalis L. (Rosemary) Extracts Containing Carnosic Acid and Carnosol are Potent Quorum Sensing Inhibitors of Staphylococcus aureus Virulence

“…The use of flavonoids and other small molecules from plants as anti-virulence agents has been reported previously and reader is directed to the excellent review by Wu et al [42]. Dong et al showed that the flavonoid morin, used in traditional Chinese medicine, directly inhibits the hemolytic activity of aerolysin, the primary virulence factor of A. hydrophila strains and protects catfish from A. hydrophila infection [43].…”