A preliminary study on amphizoic amoebae with special reference to their preference for bacterial food

Abstract

The present study was planned to screen the growth pattern of six different species of pathogenic and non pathogenic amphizoic amoebae viz. Naegleria fowleri, N. gruberi, Acanthamoeba culbertsoni, A. rhysodes, A. polyphaga and A. glebae using six different bacterial species like Escherichia coli (Strain E1 and E2 and E. coli lactose +ve), Proteus, Klebsiella and Pseudomonas as food in their in vitro growth on non-nutrient agar medium. It was observed that out of six amoebae used; the pathogenic N. fowleri and A. culbertsoni were feeding on E. coli (all the strains). Feeding these two species of bacteria, the growth of these two amoebae was luxuriant, but not so good while feeding other strains of bacteria though they fed, survived and formed cysts. The remaining four amoebae were found to feed and survive only on E. coli (all the strain) and formed cysts but showed very poor growth while feeding on other four bacterial strains. It was inferred that E. coli is the most suitable bacterial species for in vitro growth of amphizoic amoebae for various purposes. This also reiterates that there exists a complex inter-relationship between amoebae and bacteria in different habitats.