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Clonogenic Assay: Adherent Cells
Published on: March 13, 2011
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SadA-Expressing Staphylococci in the Human Gut Show Increased Cell Adherence and Internalization
Arif Luqman1, Mulugeta Nega2, Minh-Thu Nguyen2
1Microbial Genetics, Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, 72076 Tübingen, Germany; Biology Department, Institut Teknologi Sepuluh Nopember, 60111 Surabaya, Indonesia.
Cell Reports
|January 11, 2018
Summary
Certain Staphylococcus bacteria in the gut produce trace amines (TAs) using the enzyme SadA. These bacteria exhibit enhanced gut cell adherence and internalization, potentially influencing intestinal activity.
Area of Science:
- Microbiology
- Neuroscience
- Gastroenterology
Background:
- Trace amines (TAs) are biogenic amines acting as neuromodulators.
- Staphylococcus species can produce TAs via staphylococcal aromatic amino acid decarboxylase (SadA).
- SadA also synthesizes neurotransmitters like dopamine and serotonin.
Purpose of the Study:
- Investigate the role of SadA-expressing staphylococci in the human gut.
- Determine the impact of SadA on bacterial adherence and internalization.
- Elucidate the mechanisms underlying bacterial-host interactions in the intestine.
Main Methods:
- Prevalence assessment of SadA-expressing staphylococci in human gut microflora.
- In vitro assays measuring adherence to HT-29 cells.
- Quantification of bacterial internalization.
- Analysis of the role of the α2-adrenergic receptor.
Main Results:
- SadA-expressing staphylococci are common in the human intestinal microflora.
- These bacteria demonstrated significantly increased adherence and internalization with HT-29 cells.
- Tryptamine exposure enhanced adherence and internalization in a sadA mutant.
- The α2-adrenergic receptor was identified as crucial for these effects.
Conclusions:
- Staphylococci expressing SadA contribute to intestinal colonization.
- Bacterial production of TAs influences host-microbe interactions.
- These findings suggest a novel mechanism for staphylococcal gut activity.
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