Work

Integrated transcriptomic and network analysis identifies novel regulatory hubs driving biofilm formation in Streptococcus mutans

Year: 2026

Type: article

Abstract: Streptococcus mutans is a key cariogenic bacterium that forms robust biofilms on tooth surfaces, playing a central role in dental caries. Biofilm development is mediated by multiple genes, including adhesion factors ( spaP ), glucan synthesis enzymes ( gtfB , gtfC ), glucan-binding proteins ( gbpC ), and regulatory pathways such as the quorum sensing comCDE system, the two-component vicRK system, and the alternative sigma factor sigX . In this study, we performed a comparative transcriptomic analysis of publicly available RNA-Seq datasets derived from dental plaque samples of caries-active and healthy individuals (n=14, NCBI SRA) to identify key gene expression changes and regulatory networks associated with cariogenic biofilm formation. A total of 412 differentially expressed genes (DEGs) were identified, including 237 upregulated and 175 downregulated in caries-active samples. Notably, canonical biofilm-associated genes were highly upregulated: spaP (log2FC = +3.14), gtfB (log2FC = +2.87), gtfC (log2FC = +2.54), and gbpC (log2FC = +2.96). Quorum sensing regulators comC (log2FC = +1.45) and comE (log2FC = +0.98) were induced, while comD (log2FC = -0.87) was moderately downregulated. Functional enrichment analysis revealed significant involvement of pathways in quorum sensing, two-component signaling, carbohydrate metabolism, and oxidative stress response. Weighted Gene Co-expression Network Analysis (WGCNA) identified a module strongly correlated with the caries phenotype (r = 0.85), containing SMU_RS10050 as a potential novel regulatory hub. These results provide a systems-level understanding of S. mutans biofilm regulatory mechanisms in clinical datasets and highlight potential molecular targets for therapeutic intervention against cariogenic biofilms.

Source: The Microbe

DOI: 10.1016/j.microb.2026.100808

Authors: Mohsen Kazemi Hasanvand, Darab Gholami Boroujeni, Maryam Khosropour, Hosein Alavi Eshkaftaki, Matin Karbasion

Institutions: Shahrekord University, Shahrekord University of Medical Sciences, Lorestan University

Language: English

Topic: Oral microbiology and periodontitis research

Subfield: Periodontics

Field: Dentistry

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $2,150