一株兔源A型多杀性巴氏杆菌的分离鉴定和全基因组测序及分析

【背景】多杀性巴氏杆菌可导致猪肺疫、牛出血性败血症和兔出血性败血症等多种疾病，严重威胁多种动物畜牧养殖业的健康发展。【目的】重庆某兔场送检一批病死兔，为研究其病原和治疗方法，对病原进行了微生物分离和全基因组测序分析。【方法】从2022年重庆某兔场送检兔病料中进行细菌分离纯化、生化试验、16S rRNA基因鉴定、荚膜血清型分型、药敏试验和毒力基因检测，同时通过全基因组测序结果进行毒力、耐药基因注释和遗传进化等分子生物学信息分析。【结果】该菌为兔源A:ST74多杀性巴氏杆菌，命名为LXSS001，基因组序列上传到NCBI数据库(登录号为CP119523.1)，药敏试验显示该菌对四环素、杆菌肽、复方新诺明和磺胺异恶唑耐药，对头孢噻肟、头孢哌酮和丁胺卡那等药物敏感。全基因组长度为2 480 671 bp，并注释到了58个毒力基因和9类药物的靶向抗药基因。通过联合建树表明其与3480株一致性最高。【结论】本研究完成了一株A型多杀性巴氏杆菌的分离鉴定和全基因组测序，并揭示了其与国内外其他分离株的进化关系，为多杀性巴氏杆菌的后续研究提供了参考依据。

Isolation, identification, and whole genome sequencing of a rabbit-derived type A Pasteurella multocida strain

Background] Pasteurella multocida can cause various diseases such as porcine pulmonary disease, bovine hemorrhagic sepsis, and rabbit hemorrhagic sepsis, posing a serious threat to the healthy development of the animal husbandry in China. Objective] A rabbit farm in Chongqing sent a batch of sick and dead rabbits for examination. To study their pathogens and treatment methods, we carried out microbial isolation and whole genome sequencing for the pathogens. Methods] The bacterial isolation and purification, biochemical testing, 16S rRNA gene identification, capsule serotyping, drug susceptibility testing, and virulence gene testing were conducted with the diseased rabbit samples from a rabbit farm in Chongqing, 2022. The whole genome sequencing results were employed to annotate the virulence genes and drug resistance genes and build the phylogenetic tree. Results] The isolate was identified as a rabbit-derived type A Pasteurella multocida strain belonged to the sequence type ST74 and named LXSS001. The genome sequence was uploaded to NCBI (collection number:CP119523.1). The strain was resistant to tetracycline, compound sulfamethoxazole, and sulfamethoxazole, while it was sensitive to cefotaxime, cefoperazone, and amikacin and so on. The strain had the whole genome length of 2 480 671 bp and carried 58 virulence genes and resistance genes for 9 classes of antibiotics. The phylogenetic tree showed that LXSS001 had the highest homology with the 3480 strain. Conclusion] This study completed the isolation, identification, and whole genome sequencing of a type A P. multocida strain and revealed its phylogenetic relationship with other isolates, providing a basis for the subsequent research on P. multocida.