Actinobacillus pleuropneumoniae is the etiologic agent of porcine pleuropneumonia. Currently, there are 18 different serotypes; the serotype 8 is the most widely distributed in the United States, Canada, United Kingdom, and southeastern Brazil. In this study, genomes of seven A. pleuropneumoniae serotype 8 clinical isolates were compared to the other genomes of twelve serotypes. The analyses of serotype 8 genomes resulted in a set of 2352 protein-coding sequences. Of these sequences, 76.6% are present in all serotypes, 18.5% are shared with some serotypes, and 4.9% were differential. This differential portion was characterized as a series of hypothetical and regulatory protein sequences: mobile element sequence. Synteny analysis demonstrated possible events of gene recombination and acquisition by horizontal gene transfer (HGT) in this species. A total of 30 sequences related to prophages were identified in the genomes. These sequences represented 0.3 to 3.5% of the genome of the strains analyzed, and 16 of them contained complete prophages. Similarity analysis between complete prophage sequences evidenced a possible HGT with species belonging to the family Pasteurellaceae. Thus, mobile genetic elements, such as prophages, are important components of the differential portion of the A. pleuropneumoniae genome and demonstrate a central role in the evolution of the species. This study represents the first study done to understand the genome of A. pleuropneumoniae serotype 8.

中文翻译：

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胸膜肺炎放线杆菌血清型8的比较基因组学揭示了在物种的遗传变异中的噬菌体的重要性。

胸膜肺炎放线杆菌是猪胸膜肺炎的病原体。目前，有18种不同的血清型。血清型8在美国，加拿大，英国和巴西东南部分布最广泛。在这项研究中，七个胸膜肺炎放线杆菌的基因组将8种血清型临床分离株与12种血清型的其他基因组进行了比较。血清型8基因组的分析产生了2352个蛋白质编码序列。在这些序列中，所有血清型均存在76.6％，与某些血清型共有18.5％，差异为4.9％。该差异部分的特征是一系列假设的和调控的蛋白质序列：可移动元件序列。同义分析显示该物种中通过水平基因转移（HGT）进行基因重组和获取的可能事件。在基因组中总共鉴定了30个与噬菌体相关的序列。这些序列占所分析菌株基因组的0.3％至3.5％，其中16个包含完整的原噬菌体。完整的噬菌体序列之间的相似性分析表明，可能与巴斯德氏菌科的物种发生了HGT。因此，流动的遗传元件，如噬菌体，是该物种差异部分的重要组成部分。胸膜肺炎链球菌基因组并在该物种的进化中显示出核心作用。这项研究是首次了解A基因组的研究。胸膜肺炎血清型8。