The emergence and spread of carbapenem-resistant hypervirulent Klebsiella pneumoniae (CR-hvKP) is causing worldwide concern. Sequence type (ST) 86 K. pneumoniae, a major hvKP clone, is rarely resistant to carbapenem. In this study, we report the genomic features and virulence characteristics of a community-acquired bloodstream infection (CA-BSI)-causing CR-hvKP ST86 strain (KPN55602). This strain is resistant to carbapenem but sensitive to amikacin, gentamicin, tigecycline, and colistin. According to in vitro and in vivo virulence assessments, it was classified as hypervirulent. Whole-genome sequencing revealed that KPN55602 has a single 5.13 Mb chromosome and two plasmids. The chromosome of KPN55602 is phylogenetically similar to those of other sequenced ST86 strains. The incompatibility (Inc) group HI1B plasmid pK55602_1, harboring a set of virulence genes, was classified as a virulence plasmid. The IncX6 plasmid pK55602_2, carrying bla_KPC-2, was transferable through conjugation and is highly homologous to all five sequenced bla_KPC-bearing IncX6 plasmids. In conclusion, to our knowledge, this is the first report of a CA-BSI-causing CR-hvKP ST86 strain harboring an exogenous bla_KPC-2-bearing IncX6 plasmid, supplementing existing knowledge on the CR-hvKP evolutionary scenario. The IncX6 plasmid may be an important vehicle for bla_KPC, and its horizontal transfer may have led to CR-hvKP evolution in the community setting.

中文翻译：

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社区获得性血流感染引起的高毒力肺炎克雷伯菌 ST86 菌株的基因组特征和毒力特征携带 KPC-2 编码 IncX6 质粒

耐碳青霉烯类高毒力肺炎克雷伯菌(CR-hvKP)的出现和传播引起了全世界的关注。序列型 (ST) 86 K.肺炎，一个主要的 hvKP 克隆，很少对碳青霉烯耐药。在这项研究中，我们报告了社区获得性血流感染 (CA-BSI) 引起的 CR-hvKP ST86 菌株 (KPN55602) 的基因组特征和毒力特征。该菌株对碳青霉烯类耐药，但对阿米卡星、庆大霉素、替加环素和粘菌素敏感。根据体外和体内毒力评估，它被归类为高毒力。全基因组测序显示 KPN55602 有一条 5.13 Mb 的染色体和两个质粒。KPN55602 的染色体在系统发育上与其他已测序的 ST86 菌株的染色体相似。不相容性 (Inc) 组 HI1B 质粒 pK55602_1 含有一组毒力基因，被归类为毒力质粒。携带bla _KPC-2的 IncX6 质粒 pK55602_2 可通过缀合转移，并且与所有五个已测序的带有bla _{KPC 的}IncX6 质粒高度同源。总之，据我们所知，这是导致 CA-BSI 的 CR-hvKP ST86 菌株的第一份报告，该菌株含有外源性bla _KPC-2-带有 IncX6 质粒，补充了关于 CR-hvKP 进化场景的现有知识。IncX6 质粒可能是bla _KPC的重要载体，其水平转移可能导致社区环境中的 CR-hvKP 进化。