Expression of genes associated with cell wall and cytoplasmic membrane metabolism of Streptococcus mutans and the importance of selected genes in the morphology of this species

• Grant number: 23/03926-3
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2023
• End date: May 31, 2026
• Field of knowledge: Health Sciences - Dentistry
• Principal Investigator: Marlise Inêz Klein Furlan
• Grantee: Fernanda Soares Andrade
• 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

One of the aims of the Research Grant-Young Researcher 2, FAPESP 2021/06801 is to 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), associated with the virulence of this species. Therefore, this scientific initiation project will analyze the expression of genes associated with the metabolism of the cell wall and cytoplasmic membrane of S. mutans and the importance of selected genes in the cell morphology of this species. For this purpose, the parental strain S. mutans UA159 and strains with deletion of specific genes associated with glucan synthesis (DgtfB, DgtfC, DgtfBC), lipoteichoic acid metabolism (DdltA, DdltD) and cytoplasmic membrane remodeling (DlytT, DlytS) will be cultured until the beginning of the logarithmic growth phase, followed by "pulse" with glucose or sucrose. Then, an aliquot of these cultures will be processed for transmission electron microscopy (TEM) analysis to assess cell morphology. The remnants of these cultures will be processed to separate the supernatant and the precipitate (cells plus components on the outside of the cells, i.e., glucans). The supernatant will be used to analyze the pH of the spent culture medium. The precipitate will be used for RNA isolation, followed by cDNA synthesis and quantitative PCR reactions to determine the expression level of selected genes. TEM images will be analyzed qualitatively. Quantitative data will be analyzed via descriptive and inferential statistics (±=0.05). The changes in the evaluated parameters may explain how they affect the biology of the cell wall and cell membrane of S. mutans.