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Bile Salt-induced Biofilm Formation in Enteric Pathogens: Techniques for Identification and Quantification
Published on: May 6, 2018
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Biofilm formation, phenotypic production of cellulose and gene expression in Salmonella enterica decrease under
A Lamas1, J M Miranda1, B Vázquez1
1Laboratorio de Higiene Inspección y Control de Alimentos, Departamento de Química Analítica, Nutrición y Bromatología, Universidad de Santiago de Compostela, 27002 Lugo, Spain.
International Journal of Food Microbiology
|September 5, 2016
Summary
Salmonella enterica biofilm formation and cellulose production are significantly influenced by oxygen levels. Aerobic conditions promote higher biofilm production, while reduced oxygen inhibits gene expression for these traits.
Area of Science:
- Microbiology
- Food Safety
- Bacterial Pathogenesis
Background:
- Salmonella enterica subsp. enterica is a primary foodborne pathogen.
- Biofilm formation and cellulose production are key concerns for S. enterica.
- This bacterium exhibits both aerobic and anaerobic lifestyles.
Purpose of the Study:
- To investigate the impact of oxygen levels on S. enterica biofilm formation, cellulose production, and gene expression.
- To analyze morphotype variations under different atmospheric conditions.
- To understand the relationship between biofilm and quorum sensing genes.
Main Methods:
- Tested 11 S. enterica strains under aerobic, microaerobic, and anaerobic conditions.
- Assessed biofilm formation, cellulose production, and colony morphotypes.
- Quantified transcription of biofilm (csgD, adrA) and quorum sensing (sdiA, luxS) genes.
Main Results:
- Biofilm formation was significantly higher in aerobiosis (P<0.05).
- Cellulose production and RDAR morphotype were observed only in aerobiosis.
- Microaerobiosis and anaerobiosis led to SAW morphotype and small red colonies, respectively, with reduced gene expression.
Conclusions:
- Oxygen availability critically influences S. enterica biofilm formation and cellulose production.
- Reduced oxygen conditions significantly decrease the expression of key biofilm and quorum sensing genes.
- Findings are crucial for understanding contamination risks in food processing under vacuum or modified atmospheres.
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