Contribution of microbial species to the formation of the extracellular matrix of cariogenic biofilms in situ

• Grant number: 24/05965-9
• Support Opportunities: Scholarships in Brazil - Doctorate
• Effective date (Start): October 01, 2024
• Effective date (End): February 29, 2028
• Field of knowledge: Health Sciences - Dentistry
• Principal Investigator: Marlise Inêz Klein Furlan
• Grantee: Anildo Alves de Brito Júnior
• Host Institution: Faculdade de Odontologia de Piracicaba (FOP). Universidade Estadual de Campinas (UNICAMP). Piracicaba , SP, Brazil
• Associated research grant: 21/06801-1 - Extracellular matrix: from biology to strategies for controlling cariogenic biofilms, AP.JP2

Abstract

Dental caries is a biofilm-mediated disease modulated by dietary sugars, mainly sucrose. The main species known to form the extracellular matrix of cariogenic biofilms is Streptococcus mutans, but other species could contribute to the production and structuring of extracellular polymeric substances. Thus, the study aim is to investigate the contribution of microbial species (in addition to S. mutans) in the construction of the extracellular matrix of in situ biofilms subjected to a cariogenic diet regime, comparing it with a non-cariogenic diet, as such species (and their metabolic pathways) could be targets for controlling dysbiosis. The in situ study will have 16 participants (model with palatal apparatus containing dental blocks, crossover, with four phases and washout periods) that will use four solutions of each experimental group per phase, being: (1) sucrose and starch (cariogenic diet); (2) cariogenic diet+proline (potential prebiotic); (3) cariogenic diet+sodium nitrate (potential prebiotic) and (4) water (control). Biofilm analyses will include: (a) the evaluation of the matrix (chemical/molecular composition, including resistome markers in the extracellular DNA and glycoRNA detection); (b) the determination of the microbiota (DNA-seq for bacteria and fungi) and their expressed metabolic pathways (RNA-seq, detection of resistome markers in the intracellular DNA); (c) quantification of calcium and phosphate; and (d) structural characterization. The dental demineralization of the dental blocks will also be evaluated. The data will be compared with databases to identify the microbial species and detected metabolic pathways, shared or not between species (or genera), and their end products (matrix components) to determine the contribution of each to the cariogenic biofilm and whether potential prebiotics maintain biofilm homeostasis.