Bacterial-derived extracellular polysaccharides reduce antimicrobial susceptibility on biotic and abiotic surfaces

Autor(es)

Souza, Joao Gabriel S. ; Oliveira, Barbara E. Costa ; Costa, Raphael C. ; Bechara, Karen ; Cardoso-Filho, Otavio ; Benso, Bruna ; Shibli, Jamil Awad ; Bertolini, Martinna ; Barao, Valentim A. R.

• Tipo de documento: Artigo Científico
• Fonte: ARCHIVES OF ORAL BIOLOGY; v. 142, p. 9-pg., 2022-08-18.

Resumo

Objective: Extracellular biofilm matrix plays a role in reducing bacterial susceptibility against antimicrobials. Since the surface where biofilm is growing modulates microbial accumulation and bacterial-derived exopoly-saccharides (EPS) synthesis, this study compared the role of EPS to reduce antimicrobial susceptibility on biotic (dental surface) and abiotic (titanium (Ti) material) surfaces and the effect of remaining matrix-enriched biofilms to promote bacterial recolonization. Design: 48 h Streptococcus mutans UA159 strain biofilms were grown on enamel and Ti surfaces. The medium was supplemented with 1% sucrose, substrate for EPS synthesis, or with 0.5% glucose + 0.5% fructose as control. Chlorhexidine (CHX) 0.2% was used for antimicrobial treatment. Biofilms were collected and the following analyses were considered: viable bacterial counts, biofilm pH, EPS content, and biofilm structure by scanning electron microscopy and confocal laser scanning microscopy (CLSM). Substrate surfaces were analyzed by 3D laser scanning confocal microscope. Results: Enamel surface showed a higher amount of EPS content (p < 0.05), which may be explained by the higher bacterial biomass compared to Ti material. EPS content reduced bacterial susceptibility against antimi-crobial treatments for both substrates, compared to EPS control (p < 0.05). However, sucrose-treated cells presented the same magnitude of reduction for Ti or enamel. Interestingly, matrix-enriched biofilms favored bacterial recolonization for both substrates. Conclusion: The surface where the biofilm is growing modulates the amount of EPS synthesized and matrix content plays a key role in reducing antimicrobial susceptibility and promoting bacterial recolonization. (AU)

• Processo FAPESP: 20/05231-4 - Desenvolvimento de um novo hidrogel termosensitivo para liberação controlada de drogas direcionado a prevenção e ao tratamento de inflamações peri-implantares
• Beneficiário: Valentim Adelino Ricardo Barão
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 20/10436-4 - Síntese, caracterização e desempenho biológico de nanopolímeros pH-sensitivos produzidos por impressão molecular para o tratamento das infecções peri-implantares
• Beneficiário: Raphael Cavalcante Costa
• Modalidade de apoio: Bolsas no Brasil - Doutorado