Cloning and Characterization of the Full-Length cDNA of Rabies Virus Oral Vaccine Strain SRV_9

In order to obtain a more complete understanding of oral rabies vaccine candidate strain SRV_9, three cDNA fragments covering the complete genome were obtained by RT-PCR,they were cloned into pMD-18T vector separately and sequenced, the full-length cDNA of Rabies Virus Oral Vaccine Strain SRV_9 was determined(GenBank(Accession No AF499686).The glycoprotein of SRV_9 was compared both with its ancestor SAD B19 and other strains: 3aG,ERA,CVS,etc. The results indicated that there were three amino acid differences in the antigenic site between the vaccine strain SRV_9 and other virus, the 34rd amino acid in antigenic site Ⅱfrom Gly to Glu, the 333rd amino acid in antigenic site Ⅲ from Arg to Ser, the 338rd amino acid in antigenic site Ⅲ from Ile to Val. These mutations may contribute to the attenuation of the virulence and its stability.The sequence analysis would aid in understanding the mechanism of the vaccine?