Avaliação da atividade de inibição da formação e degradação de biofilme de peptídeos sintéticos bioinspirados em proteínas vegetais contra Staphylococcus aureus

Abstract

Staphylococcus aureus is a pathogenic bacterium known as resistant to antibiotics since the mid-20th century and, since then; your resistance did not stop growing, even towards the introduction of new pharmaceuticals. S. aureus has a huge medical importance, given to be the major organisms related to hospital-acquired infections (HAI). S. aureus is capable of forming biofilm, an extracellular structure that confers even more resistance to antibiotics. Over the years, studies have been conducted prospecting alternative molecules able to prevent biofilm formation, and even degrade preformed biofilms. In this context, antimicrobial peptides (AMPs) gained attention as promising alternative molecules, since their mechanisms of action can trespass bacterial resistance mechanisms. Even so, natural AMPs are economically unviable, given their low yield, low stability and toxicity to hosts. As an alternative, syntheticantimicrobial peptides (SAMPs), bioinspired in plant proteins, have been proving advantageous. The present work aimed to evaluate antibiofilm activity, and a possible synergistic effect, of eight SAMPs, in combination with the antibiotic ciprofloxacin. Out of eight, four peptides, in combination with ciprofloxacin, were capable of inhibiting S. aureus biofilm formation up to 76%. The best combination was Mo-CBP3-PepIII and ciprofloxacin. Besides the antibiofilm assay, fluorescence microscopy analysis confirmed the results and showed that the peptides act in a way that forms pores on cellular membrane and enhancing ciprofloxacin’s antibacterial activity, suggesting a synergistic effect between these molecules and their possible use as adjuvants for enhance antibiotics activity.