冷冻整鸡样本中单株猪红斑丹毒丝菌的鉴定及生物学特性

Identification and biological characteristics of single Erysipelothrix rhusiopathiae isolated from frozen whole chicken samples

中文关键词:  猪红斑丹毒丝菌  冷冻整鸡  基质辅助激光解吸电离飞行时间质谱法  全基因组测序  生物学特性

英文关键词:Erysipelothrix rhusiopathiae  frozen whole chicken  matrix assisted laser desorption ionization time of flight mass spectrometry  whole genome sequencing  biological characteristics

中文摘要:

      目的 探讨来源于冷冻整鸡样本的单株猪红斑丹毒丝菌致病性、耐药性及生物学特征, 为该菌防治提供科学依据。方法 通过基质辅助激光解吸电离飞行时间质谱法(matrix assisted laser desorption ionization time of flight mass spectrometry, MALDI-TOF MS)和全基因组测序技术进行菌株鉴定和分子生物学研究, 采用纸片扩散法(K-B法)检测其耐药表型, 通过体外生物被膜形成实验检测其生物被膜形成能力, 通过ParSNP构建亲缘关系图。结果 MALDI-TOF MS可以准确鉴定猪红斑丹毒丝菌, 该菌染色体大小为1791362 bp, 鸟嘌呤(G)+胞嘧啶(C)含量为36.5%, 含有1730个蛋白质编码序列, 53个tRNA和2个rRNA, 基因组分析暂未发现质粒; 携带四环素类耐药基因tet(M), 抗菌药物敏感性实验结果显示仅对四环素耐药, 耐药基因和耐药表型一致; 携带7个与黏附和荚膜形成相关的毒力基因; 体外生物被膜形成能力适中(2+); 与韩国分离株KC-Sb-R1亲缘关系较相近。结论 本研究阐明了冷冻整鸡样本中猪红斑丹毒丝菌分离株的生物学特性, 为该菌科学有效防控提供理论依据。

英文摘要:

      Objective To investigate the pathogenicity, drug resistance and biological characteristics of Erysipelothrix rhusiopathiae from frozen whole chicken samples, and to provide scientific basis for the control of this strain. Methods The strain was identified and studied in molecular biology by matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) and whole genome sequencing technology. The drug resistant phenotype was detected by disk diffusion method (K-B method). The biofilm formation ability was detected by in vitro biofilm formation experiment. The affinity diagram was constructed by ParSNP. Results MALDI-TOF MS could accurately identify Erysipelothrix rhusiopathiae. The assembled circular genome was 1791362 bp, and the G+C content was 36.5%; and contained 1730 protein-coding genes, 53 tRNA and 2 rRNA. No plasmid sequence was detected. Carrying tetracycline resistance gene tet(M), the results of antimicrobial susceptibility testing showed that it was resistant to tetracycline only, and the resistance gene and resistance phenotype were consistent. Carrying 7 virulence genes related to adhesion and capsule formation. In vitro, biofilm formation ability was moderate (2+), it was closely related to the strain KC-Sb-R1 separated from Korea. Conclusion This study clarified the biological characteristics of Erysipelothrix rhusiopathiae separated from frozen whole chicken samples, and will provide a scientific and valid basis for the prevention of thetransmission of this strain.