Mycobacterium avium Bacilli Grow Saprozoically in Coculture with Acanthamoeba polyphaga and Survive within Cyst Walls
AUTOR(ES)
Steinert, Michael
FONTE
American Society for Microbiology
RESUMO
Protozoans are gaining recognition as environmental hosts for a variety of waterborne pathogens. We compared the growth of Mycobacterium avium, a human pathogen associated with domestic water supplies, in coculture with the free-living amoeba Acanthamoeba polyphaga with the growth of M. avium when it was separated from amoebae by a 0.1-μm-pore-size polycarbonate membrane (in a parachamber). Although viable mycobacteria were observed within amoebal vacuoles, there was no significant difference between bacterial growth in coculture and bacterial growth in the parachamber. This suggests that M. avium is able to grow saprozoically on products secreted by the amoebae. In contrast, Legionella pneumophila, a well-studied intracellular parasite of amoebae, multiplied only in coculture. A comparison of amoebae infected with L. pneumophila and amoebae infected with M. avium by electron microscopy demonstrated that there were striking differences in the locations of the bacteria within amoebal cysts. While L. pneumophila resided within the cysts, M. avium was found within the outer walls of the double-walled cysts of A. polyphaga. These locations may provide a reservoir for the bacteria when environmental conditions become unfavorable.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=106308Documentos Relacionados
- Effects of magainins on ameba and cyst stages of Acanthamoeba polyphaga.
- Infection of Acanthamoeba polyphaga with Simkania negevensis and S. negevensis Survival within Amoebal Cysts
- Crescent Bodies of Parachlamydia acanthamoeba and Its Life Cycle within Acanthamoeba polyphaga: an Electron Micrograph Study
- Cryptococcus neoformans: pseudohyphal forms surviving culture with Acanthamoeba polyphaga.
- Acanthamoeba polyphaga Strain Age and Method of Cyst Production Influence the Observed Efficacy of Therapeutic Agents and Contact Lens Disinfectants