Paper Title
Allovahlkampfia Spelaea Is A Potential Environmental Host For Pathogenic Bacteria

Abstract
Department of Microbiology and Immunology, Faculty of Medicine, Assiut University, 71516 Assiut, Egypt. Abstract- Background: Allovahlkampfia spelaea was identified for the first time in 2009. As a free living amoeba, it has been suggested as a protective host for some bacterial pathogens against harsh environmental conditions and can transmit them to vulnerable hosts. We aimed in this study, and for the first time, to test the interactions between Allovahlkampfia spelaea and some bacteria of medical importance and if the tested bacteria can survive and multiply inside amoeba. Methods: We used a keratitis isolate of Allovahlkampfia spelaea and studied its interactions with bacterial genera which have not been tested before; MRSA, Escherichia coli 1, Klebsiella pneumoniae, Enterobacter aerogenes, Citrobacter cloaca, Proteus mirabilis, Raoultella terrigena, Raoultella ornitholytica, Aeromonas hydrophila and Pseudomonas aeruginosa. Bacterial-amoebal interactions were performed using the co-culture assays. Amoebal survival rate with different bacterial strains were determined. Results: With the exception of Proteus mirabilis, all bacterial isolates could survive and multiply inside Allovahlkampfia spelaea that was associated with decreased survival rates of the amoeba. Particularly, Pseudomonas aeruginosa, Aeromonas hydrophila and MRSA exhibited significantly increased multiplication rates. Conclusions: Pathogenic bacteria could benefit from Allovahlkampfia spelaea that protect them and act as a potential vector for their transmission to susceptible hosts. Keywords- Allovahlkampfia spelaea, amoeba-bacteria interactions, co-culture experiments, Gram negative bacilli, intracellular survival.