Vol.:(0123456789) 1 3 International Journal of Peptide Research and Therapeutics https://doi.org/10.1007/s10989-018-9760-3 Engineering, Cloning and Expression of Interleukin 2–Com1 Chimera with Aim of Recombinant Subunit Vaccine Production Against Coxiella burnetii Amin Jaydari 1  · Peyman Esmaeili Fard Barzegar 1  · Ali Forouharmehr 2  · Ali Kakanezhadifard 1  · Narges Nazif 3 Accepted: 14 September 2018 © Springer Nature B.V. 2018 Abstract Query fever is an important disease caused by Coxiella burnetii, therefore vaccination against this disease is so crucial. Com1 is one the most important immunogenic proteins of C. burnetii which can be appropriate candidate to design a subunit vaccine. It seems, fusion of this protein with interleukin 2 as a molecular adjuvant can promote its efcacy. To do current study, frst, Com1 and interleukin 2 genes were individually amplifed by PCR, then these PCR products were applied to fuse interleukin 2 with Com1 using splice overlap extension PCR. The product of splice overlap extension PCR was cloned in pTZ57R/T vector by T/A cloning strategy, after digestion, interleukin 2–Com1 gene was sub-cloned in pET-22b(+) by T4 DNA ligase enzyme. Ligation product was applied to express in BL21 (DE3) strain of Escherichia coli. Expressed interleukin 2–Com1 protein was purifed by Nik–NTA afnity column and then confrmed by sodium dodecyl sulfate poly- acrylamide gel electrophoresis and western blotting. The results of electrophoresis on agarose 1% gel revealed that, PCR of target genes and splice overlap extension PCR were successfully performed. The results of electrophoresis on 12% sodium dodecyl sulfate polyacrylamide gel confrmed expression and purifcation of interleukin 2–Com1 protein. Finally, the results of western blotting shown, purifed protein with a molecular size of 43.5 kDa belonged IL2–Com1 chimera. The results of present study shown, BL21 (DE3) is an appropriate host to express interleukin 2–Com1 protein. It seems, this chimera can be introduced as a potent candidate to fght with Query fever. Keywords Coxiella burnetii · Com1 · Subunit vaccine · Interleukin 2 · Protein expression Introduction Query fever (Q fever) is a zoonotic disease with a worldwide distribution which is caused by Coxiella burnetii. In fact, C. burnetii is known as an obligate intracellular and Gram- negative bacterium which has diferent reservoirs includ- ing; arthropods, birds and mammals (Kováčová and Kazar 2002). In general, Q fever is divided two classes including; acute and chronic, acute Q fever is usually presented as an infuenza-like illness with various degrees of pneumonia, whereas chronic Q fever is typically manifested as an endo- carditis, osteomyelitis or infected aortic aneurysms (Xiong et al. 2012). Hence, C. burnetii infection is known as an occupational hazard that can be developed to intense chronic disease in humans, consequently, vaccination against this disease must be applied to protect people who contact with infected animals and agents (Zhang and Samuel 2004). It has been revealed that formalin-inactivated phase I whole- cell vaccine is able to protect humans and animals against this disease, but use of this vaccine is limited due to its severe local and occasional systemic reactions. Therefore, applying recombinant vaccine as a superseding strategy can dominate to problems of conventional vaccines such as Q-VAX ® (Commonwealth Serum Laboratories Ltd.) (Reeves et al. 2017). Recombinant subunit vaccine (RSV) is one of the most interesting types of recombinant vaccines which employed immunogenic proteins (IP) instead of whole microorganisms. Thereby, it can be claimed, identifcation * Amin Jaydari jaydari.a@lu.ac.ir 1 Department of Microbiology, Faculty of Veterinary Medicine, Lorestan University, Khorramabad, Iran 2 Department of Animal Science, Faculty of Agriculture, Lorestan University, Khorramabad, Iran 3 Department of Animal Science, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran