Objective: Poultry industry is faced with many bacterial infections caused by garam negative bacteria such as Colibacillosis, Fowl Cholera, Salmonellosis. Viral diseases are among other threats, that need effective vaccines. Therefore, there is big demand for new strategy to fight against these diseases. Bacterial Ghosts (BGs) are safe non-living, empty envelopes, perfectly mimicking the Gram-negative bacteria from which they are derived. They are produced by controlled expression of coliphage ɸX174 E-lysis gene. The natural surface structures of the bacteria remain in BGs, which drive them highly antigenic and immunogenic. They also have a capability to serve as a delivery vehicle of DNA, protein and subunit vaccines against viral diseases. In the present work, we produce E.coli ghosts from DH5α and Top10 strains to evaluate the feasibility of the method. Materials & Methods: A molecular construct, containing E-lysis gene under control of λPR promoter and cI857 repressor were designed and ordered to be synthesized by GenScript company, USA. The cassette was ligated in pmET32a promoter-less vector, and the construct was named pmET32a-EL. The vector transformed into chemically competent E.coli DH5α and Top10. The E.coli cells were grown in LB medium at 28 °C on a rotary shaker until OD600nm reached 0.4. At this point, the temperature was increased up to 44 °C, which induce the expression of E-lysis gene and medium allowed shaking for another four hours. Sampling was performed at each hour and CFU was determined accordingly. Finally, the cells were washed five times in water and scanning electron micrograph (SEM) was taken from the cells. Results & Conclusion: CFU counting demonstrated near 80% of bacteria lysed by the first hour of induction. Nonetheless, the lysis rate was reached to more than 99% after two hours and remained constant throughout the induction period. The result from electron microscopy revealed pores in bacterial cells. These pores mostly located at two ends of cells and had a diameter around 30μm. However, the E.coli ghosts’ morphology was same as the native bacteria. Considering to these promising results, the Bacterial Ghosts platform can find its way into vaccine development research for poultry industry. Our team currently involves on other projects concerning the BGs usage for DNA vaccine delivery and colibacillosis vaccine.

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