Lactobacillus fermentum AGR1487 cell surface structures and supernatant increase paracellular permeability through
Ranjita Sengupta1,2, Rachel C Anderson1,2, Eric Altermann2,3
1Food Nutrition & Health Team, Food & Bio-based Products Group, AgResearch Grasslands, Palmerston North, 4442, New Zealand.
Microbiologyopen
|May 7, 2015
Summary
Lactobacillus fermentum AGR1487, unlike AGR1485, impairs intestinal barrier integrity. Cell surface structures affect ion permeability, while secreted components influence molecule passage, indicating multiple mechanisms of action.
Area of Science:
- Microbiology
- Gastroenterology
- Cell Biology
Background:
- Lactobacillus fermentum is a common probiotic, but strain AGR1487 was previously shown to decrease in vitro intestinal barrier integrity.
- The study investigates the mechanisms behind L. fermentum AGR1487's effect on intestinal barrier function.
Purpose of the Study:
- To compare L. fermentum AGR1487 with a non-disruptive strain, L. fermentum AGR1485, to identify factors responsible for barrier disruption.
- To elucidate the roles of cell surface structures versus secreted components in AGR1487's impact on intestinal permeability.
Main Methods:
- Phenotypic characterization of AGR1487 and AGR1485, including genome size, sugar utilization, and tolerance to acid/bile.
- Assessment of intestinal epithelial Caco-2 cell barrier integrity using transepithelial electrical resistance (TEER) and mannitol flux assays.
- Comparison of effects using live and UV-inactivated bacterial cells to differentiate surface structure and secreted component contributions.
Main Results:
- L. fermentum AGR1487 exhibited a smaller genome, different sugar utilization, and greater acid/bile tolerance compared to AGR1485.
- Both live and UV-inactivated AGR1487 decreased TEER, indicating cell surface structures' role in ion permeability.
- Only live AGR1487 increased mannitol flux, suggesting secreted components are responsible for altering the passage of uncharged molecules.
Conclusions:
- Lactobacillus fermentum AGR1487 impacts intestinal barrier integrity through multiple mechanisms.
- Cell surface structures of AGR1487 are implicated in affecting ion permeability (TEER).
- Secreted components of AGR1487 are responsible for increasing the permeability to uncharged molecules (mannitol flux).
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