Screening Mimotopes Of Two Iridoviruses By Bioinformatic And Biopanning Methods And Construction Of Prokaryotic Expression Vector

Iridovirus is one of the most serious infectious virus emerging in a variety ofmarine fishes and amphibians in recent years,which is extremely hazardous and caninduce the mortality rate of fish to30ï¼…-100ï¼…. The frequency of outbreaks of fishdiseases and suffered fish species caused by this viruses increased year by year.Vaccines is an international confirmed method of diseases defence for aquacultureanimal,which have many advantages such as safe,long-acting andenvironment-friendly. DNA vaccines have the unique virtues so that they are the firstchoice for the prevention of viral diseases in farmed fishes.In the research anddevelopment of DNA vaccines,what the researchers focuse on and pursues is howto develop and design the vaccines which have more precise and effectiveimmunogenicity, original reaction and security while the key to develope DNAvaccines is to isolate and identificate protective antigen epitope genes which caninduce bodies to produce specific immune response.In our study, we screened two mimotopes MCP216A and424AA which havestronger immunogenicity using the method of Reverse Vaccinology to analysenucleic acid sequence homology and the function of the expressed protein ofTRBIV whole genome sequences. Through PCR amplification we gained TRBIVMCP654bp candidate gene fragment including screened two mimotopes. TheTRBIV MCP654bp gene fragment was inserted into prokaryotic expression vectorpET-21a by classical molecular biology methods then the recombinant plasmidsuccessfully expressed in E.coli BL21after the IPTG induction. So our studyprovides experimental material and technical support for further development of turbot iridovirus diseases DNA vaccines.By the Ph.D.-12library we did the biopanning for the epitopes of thelymphocele virus (LCDV). Then the obtained positive phage clones were analysed insequence, phylogenetic relationships, structure and chemical nature. It is concludedthat the mimotopes we got after biopanning was the corresponding pepetides forLCDV and the prominent feature of the mimotopes are which contain a large numberof hydrophilic amino acids. The fusion peptides, RQAPELMLSTTS andARHRPKLPYTHT have high affinity with the target molecules resulting in a higherabundance.On the other hand,the mimotopes corresponding to envelope glycoprotein,MCP, TNFR of LCDV have good application prospects and the ORF119,234,075inLCDV genome also are highly valuable for study in immunology.