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Updated: Jan 31, 2026

Detection of Foodborne Bacterial Pathogens from Individual Filth Flies
Published on: February 13, 2015
Use of Two-Dimensional Electrophoresis to Explore Foodborne Bacterial Pathogen Responses to Gastrointestinal Stress
Denise Schrama1, Maria Leonor Faleiro2
1CCMAR, University of Algarve, Faro, Portugal.
Abstract:
Proteomics was applied here to study Listeria monocytogenes response to gastrointestinal stress. It separated extracted proteins by their isoelectric point (pI) in the first dimension followed by separation by molecular weight in the second dimension on a polyacrylamide gel. L. monocytogenes was grown in an appropriate culture medium after which it was transferred to a simulated cheese medium for 2 h. Bacteria were exposed to gastric stress using artificial saliva and gastric fluid for 5 min and 2 h, respectively. After each step samples were taken for protein extraction and a two-dimensional electrophoresis approach. Proteins were separated on 18 cm Immobiline DryStrip gels with a pH range of 4-7 and the protein pattern analyzed.
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