Food Toxi-infections
Code
7630
Academic unit
Faculdade de Ciências e Tecnologia
Department
Departamento de Ciências da Vida
Credits
5.0
Teacher in charge
José Paulo Nunes de Sousa Sampaio
Weekly hours
3
Total hours
46
Teaching language
Português
Objectives
Acknowledge the diversity of foodborne microbial pathogens. Understand the role of ecology in food microbiology. Understand the interactions between pathogens and Man. Get acquainted with the main virulence factors and patogenicity mechanisms. To know different approaches used in the detection of foodborne microbial pathogens. To apply different methods for the detection and characterization of foodborne pathogens. To know classical and modern methodologies for the detection of foodborne pathogens.
Prerequisites
Knowledge on general microbiology and on the main groups of microorganisms and their main characteristics.
Subject matter
1. Introduction to foodborne pathogens. Natural defenses against microbial pathogens. The human gastrointestinal system. Role of resident microbial populations. Universal requirements of a foodborne pathogen. Main aspects of pathogenesis. Distinction between food poisoning and food infection.
2. Relevant bacteria in Food Microbiology. Main characteristics and important genera of the Proteobacteria and Gram positive genera.
3. Virulence themes of Escherichia coli. The commensal and pathogenic roles of E. coli. Serotyping of pathogenic E. coli. The classification of pathogenic E. coli (virotypes). Virulence factors and pathogenic mechanisms – patogenicity islands, adhesins, fimbriae, secretion systems. Main characteristics of enterotoxigenic E. coli – the LT and ST toxins and colonization factors. The enteropathogenic strains and the “attaching effacing” mechanism, the LEE locus and the type III secretion system. The enterohemorrhagic strains and the serotype O157:H7 – Stx toxin. Pathogenesis of enteroaggregative and enteroinvasive strains. Comparison with the patogenicity caused by Salmonella spp.
4. Bacterial toxins. Chemical classification. Structure and mode of action of endotoxins. A-B toxins as examples of exotoxins. Interaction between A-B toxins and G proteins. The pore-forming toxins.
5. Pathogenesis of Staphylococcus aureus. The multifactorial virulence mechanisms. Ecology, incidence in foods and the gastroenteritis syndrome. Toxins – hemolysins, enterotoxins, toxic shock syndrome toxin. Superantigens - mechanism and epidemiology of toxic shock syndrome.
6. Characteristics and mode of action of probiotics.
Bibliography
Modern Food Microbiology. 2005. James M. Jay. Chapman & Hall, N.Y.
Food Microbiology: a Laboratory Manual. 2003. A.E. Yousef and C. Carlstrom. Wiley-Interscience.
Practical Food Microbiology. 2002. D. Roberts, M. greenwood. Blackwell Publ.
Microorganisms in Foods - Characteristics of microbial pathogens. 1996. ICMSF. Chapman & Hall, London.
Teaching method
Evaluation method
Final grade:
two tests (40% each) and oral /writen preentation (20%).
Courses
