Mutanofactin promotes bacterial adhesion and biofilm formation of cariogenic Streptococcus mutans

Abstract

Cariogenic Streptococcus mutans is known as a predominant etiological agent of dental caries due to its exceptional capacity in forming biofilms. From strains of S. mutans isolated from dental plaque, we here discover a polyketide/non-ribosomal peptide biosynthetic gene cluster, muf, which directly correlates with a strong biofilm-forming capability. We then identify the muf-associated bioactive product, mutanofactin-697 that contains a novel molecular scaffold, along with its biosynthetic logic. Further mode-of-action studies reveal mutanofactin-697 binds to S. mutans cells nonspecifically, increases bacterial hydrophobicity, and promotes bacterial adhesion and subsequent biofilm formation. Our findings provide the first example of a microbial secondary metabolite promoting biofilm formation via a physicochemical approach, highlighting the significance of secondary metabolism in mediating critical processes related to the development of dental caries.

Identification of the antibacterial action mechanism of diterpenoids through transcriptome profiling

“…They were downregulated 2-14-fold by all types of diterpenoids ( Supplementary Table 8 ). Mutanobactin, which is a hybrid polyketide/non-ribosomal peptide type compound, has an important role in increasing bacterial hydrophobicity, promoting bacterial adhesion and biofilm formation, and regulating a range of stress tolerance, including oxygen and hydrogen peroxide resistance in S. mutans ( Wu et al, 2010 ; Li et al, 2020 ). Therefore, the downregulation of these secondary metabolites seems to affect the growth of S. mutans .…”

Биология Воспаления Тканей Ротовой Полости

“…Патоген характеризуется адгезивностью к коллагену и протеогликанам органической матрицы и к гидроксилапатиту эмали. Вторичный метаболит S. mutans мутанофактин-697 усиливает гидрофобные свойства патогена и тем самым способствует адгезии микробной клетки и образованию биопленки на эмали [7]. Патоген, продуцируя бактериоцин пептидной природы -мутацин, проявляет антагонизм к конкурентным микроорганизмам.…”