In order to express the light chain variable domain(VL) and heavy chain variable domain(VH) genes of the monoclonal antibody against Goose parvovirus(GPV) NS1 protein in E. coli, and determine their binding activity to the NS1 protein. The nucleotide sequences of the VL and VH genes of the monoclonal antibody against GPV NS1 protein were optimized according to the preferred codons of E. coli, and recombinant plasmids pUC57-VL and pUC57-VH containing variable region genes were artificially synthesized. Then pUC57-VL and pUC57-VH were double digested with Bam H Ⅰ/Xho Ⅰ, and 340 bp of VL gene and 370 bp of VH gene were recovered. The target genes were inserted into the prokaryotic expression vector pET-32a through the Bam H Ⅰ/Xho Ⅰ multiple cloning sites, and the recombinant plasmids pET-VL and pET-VH were obtained. The recombinant plasmids were identified by Bam H Ⅰ single restriction enzyme digestion and Bam H Ⅰ/Xho Ⅰ double restriction enzyme digestion and sequencing. The recombinant plasmids were transformed into E. coli Rosetta(DE3), and induced by IPTG. The recombinant proteins TRX-VL and TRX-VH were expressed with molecular weights of 30.3, 31.4 ku, respectively. The purified recombinant proteins could specifically bind to the His tag monoclonal antibody. And the identification results showed that 0.4 μg of TRX-VH could specifically bind to 25 ng of GST-NS1 protein, but 0.4 μg of TRX-VL could not specifically bind to each coating amount of GST-NS1 protein. The specific binding of TRX-VH and GST-NS1 protein could be completely blocked by 1:200 diluted GPV infected goose serum.
Antibody variable domain,
YU Tianfei, XIE Pengyu, SUN Wanshu, LI Jing, YIN Haichang, LI Ming, YU Zhidan. Prokaryotic Expression of Variable Domain of Monoclonal Antibody Against Goose parvovirus NS1 Protein[J]. ACTA AGRICULTURAE BOREALI-SINICA, 2021, 36(5): 211-215. doi: 10.7668/hbnxb.20192216.