High yield expression in a recombinant E. coli of a codon optimized chicken anemia virus capsid protein VP1 useful for vaccine development

Abstract

BackgroundChicken anemia virus (CAV), the causative agent chicken anemia, is the only member of the genus Gyrovirus of the Circoviridae family. CAV is an immune suppressive virus and causes anemia, lymph organ atrophy and immunodeficiency. The production and biochemical characterization of VP1 protein and its use in a subunit vaccine or as part of a diagnostic kit would be useful to CAV infection prevention.ResultsSignificantly increased expression of the recombinant full-length VP1 capsid protein from chicken anemia virus was demonstrated using an E. coli expression system. The VP1 gene was cloned into various different expression vectors and then these were expressed in a number of different E. coli strains. The expression of CAV VP1 in E. coli was significantly increased when VP1 was fused with GST protein rather than a His-tag. By optimizing the various rare amino acid codons within the N-terminus of the VP1 protein, the expression level of the VP1 protein in E. coli BL21(DE3)-pLysS was further increased significantly. The highest protein expression level obtained was 17.5 g/L per liter of bacterial culture after induction with 0.1 mM IPTG for 2 h. After purification by GST affinity chromatography, the purified full-length VP1 protein produced in this way was demonstrated to have good antigenicity and was able to be recognized by CAV-positive chicken serum in an ELISA assay.ConclusionsPurified recombinant VP1 protein with the gene's codons optimized in the N-terminal region has potential as chimeric protein that, when expressed in E. coli, may be useful in the future for the development of subunit vaccines and diagnostic tests.

Development of a subunit vaccine containing recombinant chicken anemia virus VP1 and pigeon IFN-γ

“…Previous studies have shown that the N-terminal of the VP1 protein is highly rich in arginine residues and has been proposed to be cytotoxic in an E. coli expression system (Lai et al, 2013;Lee et al, 2011). Our results show that N129 deleted rVP-1 can be expressed in an E. coli system successfully.…”

“…Previous studies have shown that the N-terminal of the VP1 protein is highly rich in arginine residues, and it has been proposed to be cytotoxic in an Escherichia coli expression system (Lai et al, 2013;Pallister et al, 1994). The first 129 N-terminus-deleted VP1 protein (VP1Nd129) can successfully express large amounts of the protein in prokaryotic cells and can be recognized by CAVpositive chicken serum (Lee et al, 2011).…”

High yield production of pigeon circovirus capsid protein in the E. coliby evaluating the key parameters needed for protein expression

“…Nonetheless, one possibility is that protein solubility was improved [19]. Similarly, in our previous study, the addition of a GST tag to the CAV VP1 protein also improved expression in E. coli significantly compared to a His × 6 tag [13]. Thus some fusion tags would seem to be able to help improve the solubility of E. coli expressed proteins more than other tags; this occurs perhaps by promoting the correct folding of their selected fusion partner [13,19].…”

High yield expression of proteins in <i>E. coli</i> for NMR studies

“…Multiple tags can be added together in different combination for a particular protein to get better result on these issues [7]. Various studies report high yield target protein expression with Maltose binding protein (MBP) [19], Glutathione-S transferase (GST) [20], Thioredoxin fusion (TRX) [21], Hexahistidine His6-Tag [19,22], Small ubiquitinmodifier fusion (SUMO) [21], N-utilizing substance A (NusA), Protein S tag (PrS2) [18], Solubility-enhancing tag (SET) [23], Disulfide bond C (DsbC), Seventeen kilodalton protein (Skp), Phage T7 protein kinase (T7PK), Protein G B1 domain (GB1), Protein A IgG ZZ repeat domain (ZZ) [24], histidine tagged Ubiquitin (Ub) fusion and histidine tagged deubiquitylating enzyme (DUB) fusion [25]. Recent studies propose the Outer membrane protein A (OmpA), Outer membrane protein F (OmpF) and Osmotically inducible protein Y (OsmY) as fusion partners secreting protein into the growth medium of E. coli depending on culture conditions via periplasm secretion.…”