The Important Role of Metal Ions for Survival of Francisella in Water within Amoeba Environment

Figure 4

Morphology of F. novicida (a, b) and A. castellanii (c, d) was followed during the coincubation. (a) TEM analysis was performed to evaluate the morphology and structure of bacteria. Bacteria were negatively stained using 2% phosphotungstic acid. Representative images were acquired using a JEOL transmission electron microscope. Ten fields for each sample were randomly photographed. (b) By electron microscopy, we observed and described the morphology of bacteria, including their size, shape, and density. (c) The morphology of A. castellanii cells was observed using light microscopy. Representative images were acquired using an Olympus light microscope. Ten fields for each sample were randomly photographed. (d) By light microscopy, we observed and described the morphology of the amoebae including the percentage of amoeba cells present in a form of cysts. All experiments were performed in triplicate and repeated three times. Student -test, were accepted as significantly different from the control sample.

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