Agradecimentos: This paper is based on the thesis submitted by the first author to the School of Biomedical Engineering, The University of Western Ontario, London ON, Canada [46], and to Piracicaba Dental School, University of Campinas, Piracicaba SP, Brazil [47], in partial fulfillment of the requirements for the Ph.D. Programs in Biomedical Engineering and Dentistry, respectively. A preliminary report was presented at the 97th IADR General Session and Exhibition, Vancouver, BC, Canada, 2019. This study was partially supported and funded by Canadian Institutes of Health Research-CIHR (Grants 106657 and 400347); Canada Foundation for Innovation-Leaders Opportunity Fund (Grant 25116); and São Paulo Research Foundation (Grants 2014/27034-5 and 2017/02692-8) Ver menos

Abstract: Since the modification of the proteinaceous components of the Acquired Enamel Pellicle (AEP) could influence the adhesion of Streptococcus mutans, the most cariogenic bacteria, to dental surfaces, we assessed if engineered salivary peptides would affect the adherence and modulate the bacterial proteome upon adherence. Single-component AEPs were formed onto hydroxyapatite (HAp) discs by incubating them with statherin, histatin-3, DR9, DR9-DR9, DR9-RR14, RR14, and parotid saliva. Then, the discs were inoculated with S. mutans UA159 and the bacteria were allowed to adhere for 2 h, 4 h, and 8 h (n = 12/treatment/time point). The number of bacteria adhered to the HAp discs was determined at each time point and analyzed by two-way ANOVA and Bonferroni tests. Cell-wall proteins were extracted from adhered, planktonic, and inoculum (baseline) bacteria and proteome profiles were obtained after a bottom-up proteomics approach. The number of adhered bacteria significantly increased over time, being the mean values obtained at 8 h, from highest to lowest, as follows: DR9-RR14 > statherin > RR14 = DR9-DR9 > DR9 = histatin3 > saliva (p < 0.05). Treatments modulated the bacterial proteome upon adherence. The findings suggested a potential use of our engineered peptide DR9-DR9 to control S. mutans biofilm development by reducing bacterial colonization Ver menos