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Published on: July 4, 2018
Salivary mucins promote the coexistence of competing oral bacterial species
Erica Shapiro Frenkel1,2, Katharina Ribbeck2
1Biological Sciences in Dental Medicine, Harvard University, Cambridge, MA, USA.
Abstract:
Mucus forms a major ecological niche for microbiota in various locations throughout the human body such as the gastrointestinal tract, respiratory tract and oral cavity. The primary structural components of mucus are mucin glycoproteins, which crosslink to form a complex polymer network that surrounds microbes. Although the mucin matrix could create constraints that impact inhabiting microbes, little is understood about how this key environmental factor affects interspecies interactions. In this study, we develop an experimental model using gel-forming human salivary mucins to understand the influence of mucin on the viability of two competing species of oral bacteria. We use this dual-species model to show that mucins promote the coexistence of the two competing bacteria and that mucins shift cells from the mixed-species biofilm into the planktonic form. Taken together, these findings indicate that the mucus environment could influence bacterial viability by promoting a less competitive mode of growth.
Insights
Mucus, composed of mucin glycoproteins, supports the coexistence of competing oral bacteria. This mucus environment promotes a shift from biofilms to planktonic growth, influencing bacterial viability.
Area of Science:
- Microbiology
- Biochemistry
- Ecology
Background:
- Mucus is a key ecological niche for human microbiota in the gastrointestinal, respiratory, and oral tracts.
- Mucin glycoproteins form a complex polymer network that encases microbes.
- The impact of the mucin matrix on microbial interspecies interactions is not well understood.
Purpose of the Study:
- To investigate the influence of mucins on the viability of competing oral bacteria.
- To develop an experimental model using human salivary mucins for studying microbial interactions.
Main Methods:
- Utilized a dual-species model with gel-forming human salivary mucins.
- Observed the behavior and viability of two competing oral bacterial species in the presence of mucins.
Main Results:
- Mucins were found to promote the coexistence of two competing oral bacterial species.
- Mucins induced a shift in bacterial cells from a mixed-species biofilm to a planktonic form.
Conclusions:
- The mucus environment, via mucins, can influence bacterial viability.
- Mucus may promote a less competitive mode of bacterial growth, facilitating coexistence.
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