Klebsiella is a genus of Gram-negative, encapsulated, facultatively anaerobic bacteria in the Enterobacteriaceae family. With 141 file mentions across the vault, Klebsiella is one of the most frequently referenced opportunistic pathogens. The dominant species is klebsiella pneumoniae, but the genus-level page captures the shared biology — particularly the metal-dependent virulence and siderophore arsenal that drive Klebsiella's expansion during dysbiosis.
For species-level detail, see klebsiella pneumoniae.
Metal Dependencies
- Iron: Klebsiella produces multiple siderophores — enterobactin, yersiniabactin (a dual iron/nickel metallophore), and salmochelin — giving it one of the most comprehensive iron acquisition toolkits among enteric pathogens bushman 2025 nutrient metals bacteria gut infection.
- Nickel: NiFe-hydrogenases support anaerobic hydrogen oxidation in the inflamed gut, providing competitive advantage maier 2019 nickel microbial pathogenesis pendergrass 2026 nickel nec preterm gut.
- Manganese: Required for superoxide dismutase (MnSOD) defense against the oxidative burst.
- Co-selection: Metal resistance genes co-located with carbapenem resistance on shared plasmids — environmental metal exposure drives the evolution of carbapenem-resistant Klebsiella (CR-KP), one of the most urgent AMR threats globally baker austin 2006 co selection antibiotic metal resistance miranda 2022 metalloids antibiotic resistance ckd gut.
Dysbiosis Bloom
Klebsiella expansion is part of the characteristic Enterobacteriaceae bloom during inflammation:
- IBD: Enriched alongside E. coli in both Crohn's and UC khorsand 2022 enterobacteriaceae ecoli ibd ibdmdb metagenomics wang 2024 ibd integrated 16s metagenomics virulence factors.
- NEC: Enriched in preterm infant gut before NEC onset; nickel in formula may fuel expansion pendergrass 2026 nickel nec preterm gut.
- CKD: Part of uremic toxin-producing Enterobacteriaceae enrichment miranda 2022 metalloids antibiotic resistance ckd gut.
Cross-References
- klebsiella pneumoniae — species page
- enterobacteriaceae — family context
- iron — siderophore-dependent virulence
- siderophores — enterobactin, yersiniabactin (dual metallophore)
- nickel — NiFe-hydrogenase for gut colonization
- co selection — metal-carbapenem co-resistance
- antimicrobial resistance — CR-KP as critical AMR threat