Objective : Escherichia coli is a gram negative bacteria which belongs to the family Enterobacteriaceae. E.coli have numerous serotypes. Major antigens in the structure of the bacteria consist of K, H and O. Some serotypes of E.coli are pathogenic in poultry. One of the major avian pathogenic serotypes is E. Coli O2K1, that is responsible for colisepticemia in poultry flocks. The aim of this project was to produce a bacterial ghost of E. coli O2 in order to use it as an inactive vaccine to protect chicken against colibacillosis. Materials & Methods: E-lysis expression plasmid (pmET32a) with Gentamicin resistance gene, was employed to transform E. coli 02K1. The transformed bacteria were incubated at lower temperature than usual. E-Lysis gene expression was induces by elevation of temperature to 42 centigrade degree. Lysis phenomenon was monitored by measuring the optical density (OD) and viable cell counting. Production of bacterial ghost production was evaluated by EM scanning and CFU counting. Result & Conclusion : E-coli O2K1 BG was prepared and the efficiency of methodology was confirmed by electrone microscopic scanning and CFU counting. It was concluded that the method is efficient in producting bacterial ghost from E.coli 02K1. Initial experiments to immunize the chickens and challenge studies with E.coli 02K1 following exposure to infectious bronchitis virus vaccine starin H12 is under progress. Initial results showed the efficacy of the bacterial ghost vaccine. Final assessment of the efficacy of the vaccine needs completion of the project. This experiment confirm that E-Lysis gene expression is an efficient method to produce bacterial ghost from Entrobacteriacea to produce vaccine and as a delivery system for antigens and other molecules.

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