【摘要】 以口蹄疫病毒株China/ 99RNA为模板 ,反转录并扩增目的cDNA ,然后与 pGEM TEasy载体连接并转化JM10 9菌株 ,提取的重组质粒用电泳、PCRampos和EcoR1酶切法鉴定。该毒株与A10、O1K、O1Campos和TW 45毒株的核苷酸序列差异率分别为 15 .2 7%、15 .5 6 %、15 .5 6 %和 15 .49% ;氨基酸序列差异率分别为 8.2 9%、8.76 %、9.2 2 %和 10 .14%。五个毒株的L/P1连接处均为苷氨酸 (Gly) /异亮氨酸 (Ile)。序列比较表明 ,T C、A G和A C转换率较高 ,是点突变的热点核苷酸 ,是影响氨基酸稳定的因素之一。第 43 5 3、95 10 5、10 8 111、146 15 3、16 1 173、183 188和 182 187区域极有可能是L蛋白酶的活性中心 ,第 48位的H、5 1的C、6 5位的E、95位的H、10 9位的H、138位的H、148位的H和 16 5位的E可能是L蛋白酶的活性位点 ,它们在维持蛋白质的空间构像和功能方面具有重要作用更多还原

【Abstract】 Foot and mouth disease virus strain China/99 RNAs were used as templet for RT-PCR. The amplified cDNA products were cloned into pGEM-T Easy Vectors and transformed into JM\-\{109\}. The recombinant plasmids were identified by electrophoresis, EcoR 1 cleavage, and PCR. The nucleotide and amino acid sequences were compared with the L genes of the other four reference strains. The results shown that the differential ratio of L gene of China/99 with A\-\{10\},O\-1K,O\-1Campos and TW45 strains was 15.27%,15.56%,15.56% and 15.49% respectively; and that of amio acid sequences was \{8.29%,\}8.76%,9.22% and 10.14% respectively. All the conjunctions of L/P1 for five foot-and-mouth viruses are Gly/Ile. The higher conversions in T-C,A-G and A-C mostly affect the stabgle of amino acid residuses. The regions of 43-53th, 95-105th, 108-111th, 146-153th, 161-173th, 183-188th and 182-187th in L protease most probably are the active sites that play an important role in keeping configuration and function of proteins, and H\-\{48\},C\-\{51\},E\-\{65\},H\-\{95\},H\-\{109\},H\-\{138\},H\-\{148\} and E\-\{165\} may be active amino acids.更多还原