该研究从病猪的肝脏分离到一株多重耐药ST37型（Sequence type，ST）肺炎克雷伯菌KP200，ST37型是耐广谱β-内酰胺临床分离株中常见型别。基于全基因组测序数据，比较KP200和来自NCBI所有ST37型（160株）肺炎克雷伯菌毒力因子的携带情况，通过单拷贝核心基因进化分析ST37型肺炎克雷伯菌的毒力与遗传进化关系。结果表明，KP200携带7类毒力因子相关基因包括：荚膜（cpsACP、galF、gnd、ugd、manB和manC）、1型菌毛（fimBEACDFGHK）、3型菌毛（mrkABCD）、肠杆菌素（entABCDEF和fepABCDG）、沙门菌素（iroE和iroN）、气杆菌素（iutA）以及细菌Ⅵ型分泌系统T6SS（tssJFGKIBCDMHL）。携带5类以上的毒力因子的ST37型肺炎克雷伯菌占比100%。单拷贝核心基因进化分析结果显示，KP200与其他来自人源的5株肺炎克雷伯菌亲缘关系较近且毒力因子携带情况相似。该研究表明猪源ST37肺炎克雷伯菌KP200携带毒力因子种类多，具有潜在的致病性，ST37型肺炎克雷伯菌毒力因子携带情况与单拷贝核心基因进化关系存在一定的关联性。该研究结果可对ST37型别肺炎克雷伯菌的毒力与遗传进化关系的相关性提供基础数据。

In this study, a multi-drug resistant ST37 (Sequence type, ST) Klebsiella pneumoniae KP200 strain was isolated from the liver of sick swine. ST37 type is a common type among clinical isolates resistant to broad-spectrum β-lactam. Based on the whole-genome sequencing data, virulence factors carried by KP200 and all K. pneumoniae ST37 strains (160 strains) from NCBI were investigated, and the relationship between the virulence and genetic evolution of ST37 K. pneumoniae was analyzed by single-copy core gene evolution. The results showed that KP200 carried 7 types of virulence factor-related genes including capsule (cpsACP, galF, gnd, ugd, manB and manC), type 1 fimbriae (fimBEACDFGHK), type 3 fimbriae (mrkABCD), enterobactin (entABCDEF and fepABCDG), salmochelin (iroE and iroN), aerobactin (iutA) and bacterial Type VI secretion system T6SS (tssJFGKIBCDMHL). K. pneumoniae ST37 carrying more than 5 types of virulence factors accounted for 100%. The results of single-copy core gene evolution analysis showed that KP200 and the other 5 K. pneumoniae strains of human origin had a close relationship and similar virulence factors. This study showed that ST37 K. pneumoniae KP200 strains of swine origin carried a wide variety of virulence factors and had potential pathogenicity. There was an evolutionary relationship between to the virulence factors carried by ST37 K. pneumoniae and the evolution of single-copy core genes. The results of this study can provide basic data for the correlation between the virulence factors of ST37 K. pneumoniae and genetic evolution.

国家重点研发计划项目（2016YFD0500606）