Center of Infectious Diseases, West China Hospital, Sichuan University, Chengdu, China.
Department of Infection Control, Minda Hospital, Hubei Minzu University, Enshi, China.
Eur J Clin Microbiol Infect Dis. 2024 Oct;43(10):2029-2035. doi: 10.1007/s10096-024-04910-y. Epub 2024 Aug 7.
A novel KPC variant, KPC-84, identified in a Klebsiella pneumoniae isolate from China, exhibits a threonine (T) to proline (P) amino acid substitution at Ambler position 243(T243P), altering from the KPC-2 sequence. Cloning and expression of bla in Escherichia coli, with subsequent MIC assessments, revealed increased resistance to ceftazidime-avibactam and significantly reduced carbapenemase activity compared to KPC-2. Kinetic measurements showed that KPC-84 exhibited sligthly higher hydrolysis of ceftazidime and reduced affinity for avibactam compared to KPC-2. This study emphasizes the emerging diversity of KPC variants with ceftazidime-avibactam resistance, underscoring the complexity of addressing carbapenem-resistant Klebsiella pneumoniae infections.
一种新型的 KPC 变体，KPC-84，在中国分离的肺炎克雷伯菌中被鉴定出来，其在位置 243（T243P）处的丙氨酸（T）突变为脯氨酸（P），与 KPC-2 序列不同。在大肠杆菌中克隆和表达 bla，并随后进行 MIC 评估，结果显示与 KPC-2 相比，对头孢他啶-阿维巴坦的耐药性增加，且碳青霉烯酶活性显著降低。动力学测量表明，与 KPC-2 相比，KPC-84 对头孢他啶的水解稍高，对阿维巴坦的亲和力降低。本研究强调了具有头孢他啶-阿维巴坦耐药性的 KPC 变体的多样性不断增加，突显了应对耐碳青霉烯类肺炎克雷伯菌感染的复杂性。
