Cloning, expression and purification of gametocyte antigen-EmGam56 for control of poultry coccidiosis.

Poultry coccidiosis is an important devitalizing enteric protozoan disease caused by a group of obligatory intracellular apicomplexan parasites of the Genus contributing to major economic loss in commercial poultry worldwide. As the current method of chemotherapeutic control using ionophores in feed had led to development of drug resistant isolates, the need for development of prophylactic vaccines is the most viable alternate and eco-friendly control strategy as on date. Of the several candidate vaccines, the Gam 56 is one of the most promising candidates which protect the birds against , and , the three most pathogenic coccidian species infecting commercial chicken. Gam56 is a major wall forming component of macrogametocyte of and a candidate with high immunogenicity and low virulence. The present study was planned and carried out for the generation of expressed recombinant gametocyte antigen-Gam56 using pET 28(a+) as cloning vector and BL21 DE3 (pLysS) as prokaryotic expression system in a Bio-fermentor (New Brunswick™ Scientific BioFlo 310). The recombinant protein was purified by conventional (Ammonium sulphate precipitation) and by automatic purification system (AKTA prime) in Ni-NTA column for a planned immunization trial with experimental chickens.