摘要
以口蹄疫病毒强毒株China/99RNA为反转录模板 ,用一对特异性引物扩增目的cDNA ,然后与 pGEM TEasy载体连接并转化JM10 9菌株 ,再经重组质粒电泳、PCR和EcoR1酶切鉴定。序列测定和分析结果表明 ,该强毒株与A12、O1K和TW 45毒株的核苷酸差异率分别为 7 78%、6 6 2 %和 13 19%。推导的氨基酸序列差异率分别为 1 2 3%、1 84%和 5 73%。 4个毒株序列比较发现 ,China/99、O1K和TW 45三毒株的 2A/2B连接处为甘氨酸 /脯氨酸 ,A12 为精氨酸 /脯氨酸 ,而且T C转换率和A G转换率较高 ,是点突变的热点核苷酸。氨基酸差异主要存在于 2B和 2C蛋白中 ,2A基因较为保守。 2B蛋白的第 1 4,6 3 6 7,73 78,83 91,116 12 1和 12 6 131区域 ,2A蛋白的第 4 9区域和 2C蛋白的第 9 13,2 2 2 5 ,91 96 ,15 0 15 9,179 188,2 0 1 2 0 7和 2 5 8 2 6 2区域可能是重要的活性中心。
Using a virulent foot and mouth disease virus strain China/99 RNA as templet to reverse transcript,amplify its P 2 tract with a pair of primers.The amplified cDNA products were cloned into pGEM-T Easy Vectors and transformed into JM 109 ,the recombinant plasmids were identified by electrophoresis,EcoR1 cleavage,and PCR.The nucleotide sequence of the expected P 2tract was determined by Sangers DNA sequence method,and amino acid sequence was compared with the P 2tracts of the other three FMDV strains.It was shown that the differential ratios of P2 tract of China/99 with O 1K,A 12 and TW45 strains were 7.79%,6.62% and 13.79% respectively and deduced animo acid sequence were 1.23%,1.85% and 5.74%,respectively.The sequence alignment of these strains shows that the higher conversions in T-C,A-G and A-C,hot nucleotides,mostly affect the stable of amino acid residues.
出处
《畜牧兽医学报》
CAS
CSCD
北大核心
2002年第5期496-500,共5页
ACTA VETERINARIA ET ZOOTECHNICA SINICA
基金
国家"973"项目"畜禽重大疫病病原大分子结构与功能研究"资助 (G19990 1190 1)
