Expression and purification of HCMV glycoprotein B full protein in Escherichia coli

Abstract

Background: Human cytomegalovirus (HCMV) is associated with significant mortality in immunocompromised individuals and neonates and is a major concern of global public health. Some viral glycoproteins such as glycoproteins B have an important role on virus life. This herpesvirus fusion protein is a candidate for the vaccine due to its undeniable role in infection. Materials and Methods: Here we designed a full-length gB sequence optimization to increase the expression level of this protein. Numerous factors such as the adaptation index of codon, codon context, and adapted GC content based on E. coli codon usage. In addition, the ribosome binding site (RBS) of pET-15b was redesigned. Various factors such as IPTG concentration and induction time were optimized. The recombinant gB protein was purified by the Ni-sepharose column. Result: Among IPTG concentrations, and post inductions, the level of gB was higher in 1mM IPTG, and 8 hours, respectively. In hybrid purification conditions, gB protein was purified completely. Conclusion: The protein designed in this study be expressed in the prokaryotic system and with an optimal design, it can be purified properly. Our data showed that it can be used as an effective vaccine in vivo immunogenicity evaluation in the future.