BIOL3006 Lecture Notes - Lecture 3: Listeriosis, Foodborne Illness, Legionella
Document Summary
Some bacteria have learnt how to exploit our cells for their own purpose and to evade immune defence. When immune system defences are down, the pathogen can break out of the granulomas and spread. Bacterial effectors can mimic host cell proteins to allow control over the host. Bacteria have secretion systems ( injectors ) which forms syringe-like structures to penetrate the bacterial wall and host cell membrane to inject bacterial proteins into the host cell. Can invade host epithelial cells and macrophages in the gut. Causes listeriosis or food poisoning when ingesting infected food (such as cheeses and meats) Can cause meningitis in newborns or abortions in pregnant women. Cell entry: listeria proteins (internalin"s a and b) mediate entry into epithelial cells via a phagosome- like vacuole. In macrophages, scavenger receptors recognise the gram (+) coast and phagocytose it. Gram (-) and anaerobic bacteria that usually invades and replicated within amoeba that are found in dirty water.
