Kinetic and lytic in vitro properties of newly isolated bacteriophages against escherichia coli o157: h7

Abstract EN

Bacteriophages, recovered from sewage samples target E.

coli O157: H7, were tested for their biokinetic and morphological characteristics.

Bacterial lysis profile of isolated phages was performed using Escherichia coli O157: H7 (NCTC) 12900 as host bacterial cell.

Morphological characteristics of phages were visualized by transmission electron microscopy.

The multiplicity of infection (MOI) and biokinetic properties, particularly adsorption rate, rise period, latent period, and burst size were also calculated.

Electron microscopy revealed that the isolated phages P1and P3 belong to the Siphoviridae family while the P4 phage belongs to Myoviridae; similar to other E.

coli O157: H7-specific phages previously isolated.

MOI of P1 was 0.01, while P3 and P4 were 0.1 phage/bacterium.

These typical MOI yielding the higher titer of phage were used in the next phage tests.

The adsorption curve of the P1 phage was reached a 100% adsorption rate after 25 min of host exposure.

Whereas P3 and P4 were taken 35 and 30 minutes, respectively to achieve the same adsorption rate.

An implication of this is used in efficient biocontrol strategies for elimination of this bacterial pathogen from their reservoirs (cattle) as well as in the food industry.