Allende R, Kutish G F, Laegreid W, Lu Z, Lewis T L, Rock D L, Friesen J, Galeota J A, Doster A R, Osorio F A
Department of Veterinary and Biomedical Sciences, University of Nebraska-Lincoln, 68583-0905, USA.
Arch Virol. 2000;145(6):1149-61. doi: 10.1007/s007050070115.
Although live-attenuated vaccines have been used for some time to control clinical symptoms of the porcine reproductive and respiratory syndrome (PRRS), the molecular bases for the attenuated phenotype remain unclear. We had previously determined the genomic sequence of the pathogenic PRRSV 16244B. Limited comparisons of the structural protein coding sequence of an attenuated vaccine strain have shown 98% homology to the pathogenic 16244B. Here we have confirmed the attenuated phenotype and determined the genomic sequence of that attenuated PRRSV vaccine and compared it to its parental VR-2332 and the 16244B strains. The attenuated vaccine sequence was colinear with that of the strain 16244B sequence containing no gaps and 212 substitutions over 15,374 determined nucleotide sequence. We identified nine amino acid changes distributed in Nsp1β, Nsp2, Nsp10, ORF2, ORF3, ORF5 and ORF6. These changes may provide the molecular bases for the observed attenuated phenotype.
尽管减毒活疫苗已被用于控制猪繁殖与呼吸综合征（PRRS）的临床症状，但减毒表型的分子基础仍不清楚。我们之前已经确定了致病性PRRSV 16244B的基因组序列。对一种减毒疫苗株的结构蛋白编码序列进行的有限比较显示，其与致病性16244B有98%的同源性。在此，我们证实了该减毒表型，并确定了该减毒PRRSV疫苗的基因组序列，并将其与其亲本VR-2332和16244B毒株进行了比较。减毒疫苗序列与16244B毒株序列共线性，在15374个确定的核苷酸序列中没有缺口，有212个替换。我们在Nsp1β、Nsp2、Nsp10、ORF2、ORF3、ORF5和ORF6中鉴定出9个氨基酸变化。这些变化可能为观察到的减毒表型提供分子基础。
