Yu Chengjie, Sizhu Suolang, Luo Qingping, Xu Xuewen, Fu Lei, Zhang Anding
National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, Hubei 430070, China; College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei 430070, China.
College of Veterinary Medicine, Agricultural and Animal Husbandry College of Tibet University, Nyingchi, Tibet 860000, China.
Res Vet Sci. 2016 Apr;105:23-7. doi: 10.1016/j.rvsc.2016.01.013. Epub 2016 Jan 18.
Pasteurella multocida (P. multocida) was first shown to be the causative agent of fowl cholera by Louis Pasteur in 1881. First genomic study was performed on an avirulent avian strain Pm70, and until 2013, two genomes of virulent avian strains X73 and P1059 were sequenced. Comparative genome study supplied important information for further study on the pathogenesis of fowl cholera. In the previous study, a capsular serotype A strain GX-Pm was isolated from the liver of a chicken, which died during an outbreak of fowl cholera in 2011. The strain showed multiple drug resistance and was highly virulent to chickens. Therefore, the present study performed the genome sequencing and a comparative genomic analysis to reveal the candidate genes involved in virulence of P. multocida. Sequenced draft genome sequence of GX-Pm was 2,292,886 bp, contained 2941 protein-coding genes, 5 genomic islands, 4 IS elements and 2 prophage regions. Notability, all the predicted drug-resistance genes were included in predicted genomic islands. A comparative genome study on virulent avian strains P1059, X73 and GX-Pm with the avirulent avian strain Pm 70 indicated that 475 unique genes were only identified in either of virulent strains but absent in the avirulent strain. Among these genes, 20 genes were contained within genomes of all three virulent strains, including a few of putative virulence genes. Further characterization of the pathogenic functions of these genes would benefit the understanding of pathogenesis of fowl cholera.
1881年，路易·巴斯德首次证明多杀性巴氏杆菌（P. multocida）是禽霍乱的病原体。首次对无毒力禽源菌株Pm70进行了基因组研究，直到2013年，对有毒力禽源菌株X73和P1059的两个基因组进行了测序。比较基因组研究为进一步研究禽霍乱的发病机制提供了重要信息。在先前的研究中，从一只于2011年禽霍乱疫情期间死亡的鸡的肝脏中分离出一株A群荚膜血清型菌株GX-Pm。该菌株表现出多重耐药性，对鸡具有高毒力。因此，本研究进行了基因组测序和比较基因组分析，以揭示多杀性巴氏杆菌毒力相关的候选基因。GX-Pm的测序草图基因组序列为2,292,886 bp，包含2941个蛋白质编码基因、5个基因组岛、4个插入序列元件和2个前噬菌体区域。值得注意的是，所有预测的耐药基因都包含在预测的基因组岛中。对有毒力禽源菌株P1059、X73和GX-Pm与无毒力禽源菌株Pm 70进行的比较基因组研究表明，475个独特基因仅在其中一种有毒力菌株中鉴定到，而在无毒力菌株中不存在。在这些基因中，20个基因存在于所有三种有毒力菌株基因组中, 包括一些假定的毒力基因。进一步表征这些基因的致病功能将有助于理解禽霍乱的发病机制。
