Inhibitory effect of Bacillus velezensis on biofilm formation by Streptococcus mutans.

Abstract

Streptococcus mutans plays a key role in the development of dental caries and promotes the formation of oral biofilm produced by glucosyltransferases (GTFs). Bacillus velezensis K68 was isolated from traditional fermented foods and inhibits biofilm formation mediated by S. mutans. Gene amplification results demonstrated that B. velezensis K68 contained genes for the biosynthesis of 1-deoxynojirimycin (1-DNJ), a known GTF expression inhibitor. The presence of the GabT1, Yktc1, and GutB1 genes required for 1-DNJ synthesis in B. velezensis K68 was confirmed. Supernatant from B. velezensis K68 culture medium inhibited biofilm formation by 84% when S. mutans was cultured for 48 h, and inhibited it maximally when 1% glucose was added to the S. mutans culture medium as a GTF substrate. In addition, supernatant from B. velezensis K68 medium containing 3 ppb 1-DNJ decreased S. mutans cell surface hydrophobicity by 79.0 ± 0.8% compared with that of untreated control. The supernatant containing 1-DNJ decreased S. mutans adherence by 99.97% and 98.83% under sugar-dependent and sugar-independent conditions, respectively. S. mutans treated with the supernatant exhibited significantly reduced expression of the essential GTF genes gtfB, gtfC, and gtfD compared to that in the untreated group. Thus, B. velezensis inhibits biofilm formation, adhesion, and GTF gene expression of S. mutans through 1-DNJ production.

• Authors: Yesol Yoo, Dong-Ho Seo, Hyunjin Lee, Eui-Sang Cho, Nho-Eul Song, Tea Gyu Nam, Young-Do Nam, Myung-Ji Seo
• Journal: Journal of biotechnology (J Biotechnol) Vol. 298 Pg. 57-63 (Jun 10 2019) ISSN: 1873-4863 [Electronic] Netherlands
• PMID: 30986518 (Publication Type: Journal Article)
• Copyright: Copyright © 2019 Elsevier B.V. All rights reserved.

Chemical References

• Bacterial Proteins
• 1-Deoxynojirimycin
• Glucosyltransferases

Topics

• 1-Deoxynojirimycin (metabolism)
• Bacillus (metabolism)
• Bacterial Proteins (genetics)
• Biofilms (growth & development)
• Dental Caries (microbiology, prevention & control)
• Gene Expression Regulation, Bacterial
• Glucosyltransferases (antagonists & inhibitors, genetics)
• Humans
• Streptococcus mutans (metabolism, pathogenicity)