Mansour Mayahi - Faculty of Veterinary Medicine of Ahvaz
Abbas Jolodar - Department of Basic Sciences, Faculty of Veterinary Medicine, Shahid Chamran University, Ahvaz, Iran
Sharouz Masaeli - He is working at Veterinary Department of Qum State
Hosein Hamidinejat - Department of Pathobiology, Faculty of Veterinary Medicine, Shahid Chamran University, Ahvaz, Iran

Background: Coccidiosis caused by Eimeria necatrix has the most economic impact onpoultry production. Micronemal proteins in Eimeria necatrix are thoughtto be critical ligands determining host cell specificity at the time ofinvasion.               OBJECTIVES: Isolation and purification of Eimeria necatrix oocysts from  Khuzestan province of Iran was performed. AcDNA encoding microneme 5 (EnMIC5) protein was cloned and expressed asrecombinant protein before the evaluation of its immunogenicity by Westernblotting. METHODS: A primer pair was designed based on the publishednucleotide sequence of Eimeria necatrix LZ strain micronem5 gene. APartial cDNA sequence fragment of 758 bp coding for microneme 5 protein(EnMIC5) was amplified by semi- Nested RT-PCR. PCR products were cloned andexpressed in a Maltose Binding protein (MBP) containing expression vector(pMAL-c2x) in Escherichia coli. The cDNA which is encoded for 252 aminoacids shows high degree of conservation. It contains the adhesive plasmapre-kallikrein and seven hydrophilic motifs. RESULTS: The results of SDS-PAGErevealed that the recombinant protein with a molecular weight of 70 kDa wasover-expressed after induction with IPTG. Western blotting results revealedthat the expressed recombinant protein was reacted with sera of the chicksinfected with Eimeria necatrix. It was suggested that this proteinshould have a good immunogenicity and can be used for further studies. CONCLUSIONS: In conclusion, the high degree of sequence homology indicates that thisprotein is immunogenic and  might be aninteresting vaccine target, and deserves further investigation

Eimeria necatrix, Gene expression, immunogenicity, microneme