Acanthamoeba sp. promotes the survival and growth of Acinetobacter baumanii

Laboratoire de parasitologie et mycologie médicale, Faculté de médecine et de pharmacie, Poitiers, France.
FEMS Microbiology Letters (Impact Factor: 2.12). 03/2011; 319(1):19-25. DOI: 10.1111/j.1574-6968.2011.02261.x
Source: PubMed


Acinetobacter baumanii, which may be found in water, is an important emerging hospital-acquired pathogen. Free-living amoebae can be recovered from the same water networks, and it has been shown that these protozoa may support the growth of other bacteria. In this paper, we have studied potential relationships between A. baumanii and Acanthamoeba species. Two strains of A. baumanii isolated from hospital water were co-cultivated with the trophozoites or supernatants of two free-living amoebae strains: Acanthamoeba castellanii or Acanthamoeba culbertsoni. Firstly, the presence of the amoebae or their supernatants induced a major increase in A. baumanii growth, compared with controls. Secondly, A. baumanii affected only the viability of A. culbertsonii, with no effect on A. castellanii. Electron microscopy observations of the cultures investigating the bacterial location in the protozoa showed persistence of the bacteria within cyst wall even after 60 days of incubation. In our study, the survival and growth of A. baumanii could be favored by Acanthamoeba strains. Special attention should consequently be paid to the presence of free-living amoebae in hospital water systems, which can promote A. baumanii persistence.

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Available from: Yann Hechard, Nov 12, 2014
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    • "Bacterial pathogens including Vibrio, Legionella, Mycobacterium , enteropathogenic E. coli, and the meningitis-causing E. coli strain K1 multiply and/or survive within protozoa (King et al. 1988; Barker and Brown 1994; Fields 1996; Steinert et al. 1998; Abd et al. 2005; Alsam et al. 2006). The Acanthamoeba species, which are free-living amoebae , are naturally occurring hosts of several water-borne pathogens (Sandstrom et al. 2010; Cateau et al. 2011). These protozoa are known to resist various stress conditions (Coulon et al. 2010; Mogoa et al. 2010, 2011). "
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