Abstract:

Objective To establish a method to express high soluble 1D protein from foot-and-mouth disease virus type A in Escherichia coli(E. coli). Methods Based on the nucleic acid sequences of the foot-and-mouth disease virus type A, the 1D protein genes of FMDV A/GDMM/CHA/2013 was obtained. Truncation and optimization were performed. The fusion tags were screened in order to obtain soluble expression of CcFnt166AS protein. The 135 aminoacid ferritin protein was isolated from Campylobacter coli and linked with the 1D protein, which was named as CcFnt166AS. We constructed prokaryotic expression vectors fused with nine different fusion tags (Grifin, GST, MBP, Sumo, Thioredoxin, γ-crystallin, ArsC, PpiB, CeHSP17)fragments, these recombinant plasmids were transformed into Escherichia coli BL21(DE3) and induced by isopropyl β-D-thiogalactoside(IPTG). SDS-PAGE analysis was used to identify the soluble expression of recombinant protein after ultrasonic decomposition. The fusion tag that could significantly promote soluble expression of CcFnt166AS protein was selected. Abundantly inducible expression recombinant protein was purified by Ni-NTA purification sysm and detected by electron microscopy. Results We successfully constructed the recombinant prokaryotic expression plasmid and obtained the high purity MBP-CcFnt166AS. The result of electron microscopy showed that MBP-CcFnt166AS formed nano-sized particles. Conclusion These result suggested that we established a method to generate CcFnt166AS recombinant protein, which may lay a foundation for the development and subsequent study of FMDV structure vaccine.

Key words: A-type foot-and-mouth disease virus, 1D protein, Ferritin, Fusion tag, solubility, Nanoparticle, Electron microscopy, Eschericha coli