Role Of glgC In Cariogenic Potential Of Streptococcus Mutans

Aim or purpose: This study investigates the role of the glgC gene in regulating the cariogenic potential of Streptococcus mutans (S. mutans) ATCC 25175. Materials and methods: The S. mutans glgC knockout strain (S. mutansΔglgC) was constructed by homologous recombination. Growth activity and acid tolerance were assessed by growth curves. Acid production levels were measured using a pH meter, lactate and LDH kits. Scanning electron microscopy (SEM) was used to observe biofilm structure differences. Biofilm formation and EPS synthesis were compared using crystal violet staining, anthrone-sulfuric acid method, and Confocal Laser Scanning Microscopy (CLSM). Growth in natural saliva was observed to simulate oral colonization. Results: 1. S. mutansΔglgC showed lower growth activity and reduced acid tolerance, with significantly lower lactate and LDH activity. 2. Biofilm density and structure of S. mutansΔglgC were weaker, with significantly reduced biofilm formation and EPS synthesis compared to S. mutans (P < 0.05). 3. Biofilm formation in natural saliva was significantly weaker in S. mutansΔglgC. Conclusions: The glgC gene plays a crucial role in regulating the cariogenic potential of S. mutans. Its knockout significantly weakened biofilm formation, EPS synthesis, acid production, acid tolerance, and oral colonization. Therefore, glgC may be a potential target for controlling the cariogenic potential and biofilm formation of S. mutans.