Effects of Biosurfactant-Producing Bacteria Bacillus pumilus MMLN01 on Major Virulence Factors of Streptococcus mutans.

Abstract

Streptococcus mutans, primarily responsible for dental caries, results in tooth demineralization due to plaque buildup and high sugar consumption. Glucosyltransferases produced by S. mutans synthesize virulent extracellular polysaccharides, enhancing cariogenic biofilms. Sucrose activates glucosyltransferase, leading to glucan synthesis, a key factor in caries formation. This study analyzed the effect of biosurfactant-producing bacteria extracted from the oral microbiota on Streptococcus mutans MTCC 497 targeting glucosyltransferase and ATPase. Oral swabs from healthy individuals from different states in India were screened for biosurfactant production using various assays such as oil drop collapse, CTAB methylene blue agar, and emulsification activity. The inhibitory effect of biosurfactants on S. mutans MTCC 497 were analyzed with minimum inhibitory broth concentration, sucrose dependent and sucrose independent adhesion and biofilm formation assays. Of 100 oral swabs, 40 bacterial isolates demonstrated antagonistic activity against S. mutans MTCC 497. From that, 17 biosurfactant-producing bacteria were identified. Ten bacteria, including DMTMM46, were assessed through various assays. DMTMM46 exhibited significant activity against Streptococcus mutans MTCC 497. Biosurfactants demonstrated efficacy in glucan synthesis, adhesion, biofilm formation, and ATPase activity at 75 µg/mL. Identification through 16SrRNA sequencing revealed DMTMM46 as Bacillus pumilus. The results indicate that biosurfactant produced by the bacteria Bacillus pumilus MMLN01 have therapeutic potential for dental caries.

Supplementary information: The online version contains supplementary material available at 10.1007/s12088-024-01393-5.