Arginine-induced metabolomic perturbation in Streptococcus mutans

BACKGROUND: Streptococcus mutans is a major pathogen responsible for dental caries. Arginine is a promising potential caries preventive agent which can inhibit the growth of S. mutans. However, the mechanism whereby arginine inhibits S. mutans growth remains unclear. AIM: To assess the impact of arginine-induced metabolomic perturbations on S. mutans under biofilm conditions. METHODS: We identified 5,933 and 7,413 ions in positive (ESI+) and negative (ESI-) electrospray ion modes, respectively, with a total of 11.05% and 11.58% differential ions subsequently detected in two respective modes. Further analyses of these metabolites led to identification of 8 and 22 metabolic pathways that were affected by arginine treatment in ESI+ and ESI- modes., RESULTS: Once or twice daily treatments of S. mutans biofilms with arginine resulted in reductions in biofilm biomass. Significant reductions in EPS production were observed following twice daily arginine treatments. Identified metabolites that were significantly differentially abundant following arginine treatment were associated with glycolysis metabolism, amino sugar and nucleotide sugar metabolism, and peptidoglycan synthesis. CONCLUSIONS: Arginine can reduce S. mutans biofilm growth and acid production by inhibiting glycolysis, amino sugar and nucleotide sugar metabolism, and peptidoglycan synthesis.