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Updated: Mar 30, 2026
In Vitro Assay of Bacterial Adhesion onto Mammalian Epithelial Cells
Published on: May 16, 2011
Bacillus cereus Adhesion to Simulated Intestinal Mucus Is Determined by Its Growth on Mucin, Rather Than Intestinal
Varvara Tsilia1,2, Mieke Uyttendaele2, Frederiek-Maarten Kerckhof1
11 Laboratory of Microbial Ecology and Technology (LabMET), Department of Biochemical and Microbial Technology, Ghent University, Ghent, Belgium .
Abstract:
Adhesion of pathogenic bacteria to intestinal mucus, the protective layer of the gastrointestinal epithelium, is often considered a virulence factor. The ability of food-poisoning Bacillus cereus strains to attach to mucus and the factors affecting this interaction have not yet been investigated. Therefore, the role of adhesion in pathogenesis of B. cereus still remains unknown. In the present study, an in vitro assay based on mucin agar was used to simulate adhesion of B. cereus to mucus. Bacterial-associated factors (e.g., strain specificity and microbial competition) known to influence adhesion to different surfaces and a variety of environmental conditions (e.g., pH and oxygen) encountered in the gastrointestinal tract were investigated. The effect of these parameters on B. cereus NVH 0500/00 mucin adhesion was generally limited even in the presence of microbial competition. This suggests that B. cereus NVH 0500/00 is a versatile pathogen. Inoculation of 4 to 5 log colony-forming units (CFU) per milliliter. B. cereus NVH 0500/00 resulted in 5-6 log CFU/mL mucin-associated bacteria after a short incubation period. This indicates that this pathogenic strain could grow in the presence of mucin agar. This growth may potentially mask the effect of the studied conditions. Yet, extensive attachment of B. cereus to mucin is not necessarily a prerequisite for virulence, because other pathogenic strains do not adhere with the same efficiency to mucin. Nevertheless, adhesion may contribute to the disease by providing close contact to nutrient sources, such as mucin, which would not only result in bacterial proliferation, but also in disruption of the protective host mucus surface.
Insights
Bacillus cereus adhesion to intestinal mucus is not fully understood. This study found limited effects of environmental factors on B. cereus mucin adhesion, suggesting versatility, but adhesion may still aid virulence.
Area of Science:
- Microbiology
- Gastroenterology
- Pathogenesis
Background:
- Bacterial adhesion to intestinal mucus is a key virulence factor for many pathogens.
- The role of mucus adhesion in Bacillus cereus pathogenesis remains largely uninvestigated.
- Understanding these interactions is crucial for food safety and public health.
Purpose of the Study:
- To investigate the in vitro adhesion of food-poisoning Bacillus cereus strains to intestinal mucus.
- To determine the influence of bacterial factors and environmental conditions on B. cereus mucin adhesion.
- To elucidate the potential role of mucus adhesion in B. cereus virulence.
Main Methods:
- Utilized a mucin agar assay to simulate in vitro adhesion of B. cereus to mucus.
- Investigated bacterial factors like strain specificity and microbial competition.
- Examined environmental conditions including pH and oxygen levels relevant to the gastrointestinal tract.
Main Results:
- The adhesion of B. cereus NVH 0500/00 to mucin showed limited sensitivity to tested environmental conditions and microbial competition.
- The pathogen demonstrated significant growth in the presence of mucin agar, potentially influencing adhesion assays.
- Varied adhesion efficiencies were observed among different pathogenic B. cereus strains.
Conclusions:
- Bacillus cereus NVH 0500/00 exhibits versatile adhesion capabilities, with limited impact from environmental factors.
- Extensive mucin adhesion is not a strict prerequisite for virulence in all B. cereus strains.
- Bacterial adhesion to mucus may contribute to virulence by facilitating nutrient access and disrupting the host's protective mucus layer.
