- Autor(in)
- Seitenbereich
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167 - 183
- Zusammenfsg.
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Free-living amoeba live in close association with other microorganisms in the same ecological niches, feeding on bacteria and fungi. The efficiency of consumption is different, depending on protozoan type and growth state, temperature, bacterial abundance, and size and nature of bacterial prey. Many of the bacteria are digested, especially enterobacteria which are used as nutriment. Gram positive bacteria seem to be digested slower, owing to their thick cell wall. Some bacteria may avoid digestion by liberation out of the phagosome before lysosomal fusion or resist the cellular mechanisms of digestion in phagosomes and escape into the host cell cytoplasm where they multiply. A number of bacteria have been reported to survive as parasites or endosymbionts of free-living amoeba, and some of these bacteria are also potential pathogens to vertebrates. Free-living amoeba are incriminated in the ecology and epidemiology of legionellosis. They are also likely to be natural hosts for well-known pathogens like Vibrio cholerae and Listeria monocytogenes, or nosocomial new pathogens, like Xanthomonas maltophilia and Flavobacterium sp. Their interacting with protozoa in biofilms associated to intracellular replication and inclusion of pathogen bacteria in cysts give these pathogens a possibility of survival and transmission in unfavourable conditions.