猪传染性胸膜肺炎放线杆菌血清5a型ApxⅣA全基因的序列测序及其分子特征

根据GenBank上公布的猪传染性胸膜肺炎放线杆菌(APP)血清型1型和血清型3型ApxⅣA基因全序列,设计了7对引物,对APP血清5a型毒株263株ApxⅣA基因全序列进行了分段PCR扩增和克隆。序列测定结果表明:该基因核酸序列全长5856 bp,比GenBank上公布的血清1型和3型的相应基因核酸序列分别长438 bp和1287 bp,与其核酸和氨基酸序列同源率均分别为95.5%和87.6%;与GenBank刚公布的血清5b型毒株L20株的核酸和氨基酸序列的同源性均为98.2%。生物信息学分析表明,该基因编码的蛋白具有较强的亲水性,共有66个抗原决定簇,存在较多的可能性功能位点。

Complete Sequencing of ApxⅣA Gene of Actinobacillus pleuropneumonia Serotype 5a and Its Molecular Character

According to the published sequences of Actinobacillus pleuropneumonia (APP) serotype 1 and serotype 3 on GenBank, seven pairs of primers were designed and the ApxⅣA gene of serotype 5a strain 263 was amplified by PCR and cloned by PMD-18T. The results showed that the ApxⅣA gene of APP serotype 5a was 5856 bp in length, 438 bp and 1287 bp longer than those of APP serotype 1 and 3 respectively. The homology percentage of nucleotide sequence and amino acid sequence of ApxⅣA gene of APP serotype 5a with those of serotype 1 and serotype 3 were 95.5% and 87.6% respectively. The nucleotide sequence and amino acids homology of ApxⅣA gene of APP serotype 5a with those of APP serotype 5b published on GeneBank was 98.2%. Bioinformatics analysis of this sequence showed that ApxⅣA protein was highly hydrophilic and antigenic, possessing 66 antigenic determinants, probably with many functional sites.