MICR 2420 Lecture Notes - Lecture 18: Antibiotics, Exotoxin, Pasteurization
7 Dec 2017
School
Department
Course
Professor
Document Summary
Examples of pathogen e. coli o157:h7: coli, phylum: proteobacteria, family: enterobacteriaceae, gram negative, facultative anaerobe, most strains are motile using flagella. History: first description of e. coli o157:h7, 1982, four patients with bloody diarrhea, linked to undercooked hamburgers at a fast food chain, other sources identified over time, now a major problem. Initiates a cascade of signalling and cytoskeletal rearrangement to form a pedestal. Shiga toxin: originally comes from a bacteriophage, exotoxin, very similar to toxin produced by shigella dysenteriae, shiga toxin producing e. coli, acts to inhibit protein synthesis within target cells, 2 subunits to this exotoxin: a and b. Transmission: transmitted via food, transmitted via water, direct person to person contact, healthy cattle are the major reservoir for human infection, bacterial cells can survive in manure and water troughs. Infection is more common during the summer in both the northern and southern hemisphere.
