Expression of the protein gp40/15 Cryptosporidium parvum in E. coli

Background: Cryptosporidium is a parasitic protozoa of medical and veterinary importance that causes gastroenteritis in a variety of vertebrate hosts. Some of the parasite surface antigens such as gp40/15 play an important role in attaching and invasion to host cell and stimulating the immune system. The possible access to recombinant proteins of the parasite can be provided by cloning and expression of these antigens. The aim of this study was to study the gene expression of gp40/15 Cryptosporidium parvum in Escherichia coli (E. coli). Materials and Methods: The sequence of gene gp40/15 for Cryptosporidium parvum was extracted from GenBank (No.AF155624) and was synthetically cloned in PET28a+. The recombinant plasmid was confirmed by the colony PCR and the BamHI and XhoI restriction enzymes. The recombinant plasmid was transferred into E. coli and the protein expression was verified using SDS-PAGE, Western blot and ELISA which was then purified by column chromatography. Results: The results showed that the gene gp40/15 was cloned into PET28a+ plasmid. The confirmation of isolated gene cloned in PET28a+ was done by colony PCR, restriction enzymes which showed a 921bp band. The PET28a-gp40/15 plasmid expressed in E. coli showed a 43 kDa band which was confirmed using the SDS-PAGE, Western blotting and ELISA. Conclusion: The results showed that the gene gp40/15 successfully cloned into the expression plasmid PET28a+ expressed in E.coli and recombinant protein gp40/15 is produced in it. Therefore, the recombinant protein can be used to design recombinant vaccines and diagnostic kits in further.