Dai Liting, Zhang Huimin, Cao Yingyi, Ding Jiacheng, Tang Jiaxin, Xiao Zhirou, Chen Zhemei, Ling Jiahui, Zou Mengxue, Cao Xiwu, Lin Lijuan, Xu Ziheng, Liu Wanting, Chen Dingqiang, Yuan Peibo
Microbiome Medicine Center, Department of Laboratory Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong, 510120, People's Republic of China.
Department of Clinical Laboratory, National Center for Respiratory Medicine, National Clinical Research Center for Respiratory Disease, State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, 510120, People's Republic of China.
Infect Drug Resist. 2025 Jul 7;18:3383-3394. doi: 10.2147/IDR.S521566. eCollection 2025.
The emergence of strains that co-produce multiple carbapenemases poses significant threats to clinical management; however, the molecular adaptations driving their resilience remain poorly characterized.
This study aimed to investigate the resistance and adaptive mechanisms of the and co-producing KP4 strains. The antimicrobial susceptibility of KP4 was determined using Vitek, a carbapenemase inhibitor enhancement assay, and single-cell Raman spectroscopy. Transcriptomic profiling was used to identify key pathways involved in meropenem tolerance and key differentially expressed genes (DEGs). Transcriptomic analysis mapped stress-responsive pathways and DEGs, whereas qPCR validated carbapenemase gene expression and plasmid copy number variation. Biofilm dynamics were assessed under antibiotic pressure conditions.
KP4 exhibited pan-drug resistance, while retaining tigecycline susceptibility. Meropenem exposure (256 mg/L) triggered 161 DEGs primarily associated with metabolic pathways, including arginine biosynthesis, amino acid metabolism, and secondary metabolite production. Notably, qPCR quantification of bacterial DNA revealed plasmid copy number amplification of (+2.58-fold, <0.05) and (+1.49-fold, =0.156), which may be associated with upregulation of the gene on the -located plasmid and the gene on the chromosome. Meropenem exposure enhanced biofilm formation by 42% (<0.01), driven by the upregulation (tryptophan synthesis, 4.2-fold), (exopolysaccharide production, 2.1-fold), and (glycine metabolism, 2.05-fold).
and co-producing employ a two-pronged resistance strategy: plasmid amplification ensures enzymatic overdose, while biofilm induction creates physical barriers. These findings decode the survival strategies of pan-resistant pathogens and inform novel therapeutic approaches that target plasmid stability and biofilm disruption.
共产生多种碳青霉烯酶的菌株的出现对临床治疗构成了重大威胁；然而，驱动其耐药性的分子适应性仍未得到充分表征。
本研究旨在调查产 KPC 和 NDM 的肺炎克雷伯菌 KP4 菌株的耐药性及适应性机制。使用 Vitek、碳青霉烯酶抑制剂增强试验和单细胞拉曼光谱法测定 KP4 的抗菌药敏性。转录组分析用于确定参与美罗培南耐受性的关键途径和关键差异表达基因（DEG）。转录组分析绘制了应激反应途径和 DEG，而 qPCR 验证了碳青霉烯酶基因表达和质粒拷贝数变异。在抗生素压力条件下评估生物膜动态。
KP4 表现出泛耐药性，但对替加环素仍敏感。美罗培南暴露（256 mg/L）引发了 161 个主要与代谢途径相关的 DEG，包括精氨酸生物合成、氨基酸代谢和次级代谢产物生成。值得注意的是，细菌 DNA 的 qPCR 定量显示 blaKPC（+2.58 倍，P<0.05）和 blaNDM（+1.49 倍，P = 0.156）的质粒拷贝数增加，这可能与位于 IncF 质粒上的 blaKPC 基因和染色体上的 blaNDM 基因上调有关。美罗培南暴露使生物膜形成增加了 42%（P<0.01），这是由 trpA（色氨酸合成，4.2 倍）、wza（胞外多糖产生，2.1 倍）和 gcvT2（甘氨酸代谢，2.05 倍）的上调驱动的。
产 KPC 和 NDM 的肺炎克雷伯菌采用双管齐下的耐药策略：blaKPC 质粒扩增确保酶过量产生，而生物膜诱导形成物理屏障。这些发现揭示了泛耐药病原体的生存策略，并为针对质粒稳定性和生物膜破坏的新型治疗方法提供了依据。
