KPC-2 Orchestrates Systemic Metabolic Rewiring to Facilitate Antibiotic Adaptation in Klebsiella pneumoniae

The prevalence of blaKPC-carrying Klebsiella pneumoniae poses a significant clinical challenge, yet its systematic metabolic adaptations remain poorly understood. We employed an engineered K. pneumoniae (pACYC184/KPC-2) model and UHPLC-QE-Orbitrap-MS-based untargeted metabolomics to characterize metabolic shifts under steady-state and antibiotic-stressed conditions. OPLS-DA revealed profound metabolic divergence induced by KPC-2. At steady state, the 96 differential metabolites (30 up-regulated, 66 down-regulated) indicated enhanced cell membrane and nucleotide metabolism but suppressed carbohydrate and amino acid pathways. Under antibiotic challenge, the 90 differential metabolites (49 up-regulated, 41 down-regulated) indicated activated porphyrin, purine, and aromatic amino acid metabolism, alongside inhibited respiratory chain and lipid oxidative processes. NADH, FAD, and UDP were identified as core regulatory nodes. Our findings suggest that KPC-2 is associated with systematic metabolic rewiring that may facilitate bacterial survival and adaptation. These metabolic signatures provide novel insights into the putative physiological cost of resistance and potential therapeutic targets.