Extracellular matrix: from biology to strategies for controlling cariogenic biofilms

Abstract

Microbial biofilms are ubiquitous and fundamental for several natural and industrial processes and disease development. Dental caries results from dysbiosis in biofilm caused by microbial metabolism of dietary carbohydrates. These carbohydrates are substrates to produce extracellular matrix components and organic acids. These acids are trapped by the matrix inside the biofilm and at the interface of biofilm/teeth. Over time, these acids demineralize the surfaces and lead to teeth structure loss, affecting oral and systemic health. The main matrix components are exopolysaccharides (soluble and insoluble), extracellular DNA, and lipoteichoic acids. The association of these components restricts the diffusion of substances in and out of biofilms and renders them resistant. The main goal is to unravel the biology of the extracellular matrix for the coordinated construction of cariogenic biofilm and develop strategies for controlling them. Thus, we propose to: 1) determine how Streptococcus mutans (main known matrix producer species) cell wall and membrane turnover affects the bridging of extracellular matrix components and consequent configuration (creation of microniches); 2) evaluate how non-matrix producers' species benefit from the matrix assembled by S. mutans and how localized alkali production by early colonizers interferes with the matrix; 3) determine the contribution of species (other than S. mutans) to the matrix build-up during the development of in situ biofilms; these species (their pathways) could be targeted to control dysbiosis; 4) assess the efficacy of drugs associated or not with nanotechnology for the prevention of dental caries in vivo, including the evaluation of the microbiota (diversity), matrix (matrixome), aspects associated with antimicrobial tolerance and resistance (resistome), and demineralization. (AU)