Poster (Painel)
790-1Rhipicephalus (Boophilus) microplus-associated bacteria present remarkable anti-biofilm and anti-Tritrichomonas foetus activity
Autores:Karine Rigon Zimmer (CBIOT - UFRGS - Centro de Biotecnologia do Estado do Rio Grande do Sul) ; Adriana Seixas (CBIOT - UFRGS - Centro de Biotecnologia do Estado do Rio Grande do Sul) ; Jordan Martins Conceição (CBIOT - UFRGS - Centro de Biotecnologia do Estado do Rio Grande do Sul) ; Dejoara de Angelis Zvoboda (UFRGS - Faculdade de Farmácia) ; Muriel Primon de Barros (UFRGS - Faculdade de Farmácia) ; Tiana Tasca (UFRGS - Faculdade de Farmácia) ; Alexandre José Macedo (CBIOT - UFRGS - Centro de Biotecnologia do Estado do Rio Grande do Sul / UFRGS - Faculdade de Farmácia) ; Carlos Termignoni (CBIOT - UFRGS - Centro de Biotecnologia do Estado do Rio Grande do Sul)


Ticks are well known to act as vectors of several pathogenic bacteria but also harbour a variety of symbionts. Rhipicephalus microplus is constantly in contact with several microorganisms, including pathogens, being challenged by several of them. In addition to its innate defense mechanism, the tick can benefit from metabolites produced by symbionts, in a defense mechanism against predators. The goal of this study was to investigate the R. microplus associated bacteria distributed in different tissues as gut, ovary, salivary glands, and Gené organ, regarding their ability to protect its host. Using fifteen distinct culture media, fourteen bacteria were isolated from R. microplus tissues media belonging to the genera Aeromonas, Bacillus, Brevibacillus, Castelaniella, Comamonas, Kocuria, and Microbacterium. Staphylococcus epidermidis ATCC35984 and Pseudomonas aeruginosa PA14 were used as model for the assessment of biofilm and bacterial growth inhibition. For anti-biofilm assay, two surfaces (polystyrene and glass) were evaluated by crystal violet method. Almost all of the culture filtrates tested (92%) were able to inhibit more than 50% of S. epidermidis biofilm on the glass surface, while on polystyrene 71% of the filtrates inhibited more than 50% of the biofilm. Most of the culture filtrates (85%) inhibited more than 50% P. aeruginosa biofilm in glass, while 71% of the filtrates showed inhibitory effect when biofilm formation was evaluated on polystyrene surface. The inhibitory effect on P. aeruginosa and S. epidermidis biofilms by culture filtrates was evaluated by scanning electron microscopy. Treated biofilms displayed a strong decrease in the adherent cells. In many cases, the bacterial cells were found as single cells, with no indication of cell aggregates. Interestingly, the culture filtrates were cytotoxic against Tritrichomonas foetus, but they did not impair Trichomonas vaginalis viability. The results of our study give evidence of the production of compounds with anti-biofilm and trichomonicidal activity by bacteria present in the R. microplus tissues. This work opens the prospects to discover new anti-biofilm and trichomonicidal active molecules produced by tick-harbored bacteria. Besides a putative role in tick and host defenses, these molecules have potential for medical and biotechnological applications.

Palavras-chave:  Rhipicephalus (Boophilus) microplus, microbiota, anti-biofilm, trichomonicidal