Klebsiella pneumoniae

cellular organisms|Bacteria|Pseudomonadati|Pseudomonadota|Gammaproteobacteria|Enterobacterales|Enterobacteriaceae|Klebsiella
Synonyms: Bacillus pneumoniae; Hyalococcus pneumoniae
MCA-BAC-000054
TaxID: 573 | BacDive: 4946 | Rank: species
Biology & Ecology
Biology
Gram Statusgram-negative
Oxygen Tolerancefacultative anaerobe
Morphologybacillus (rod)
Ecology
Primary Nichesgut
Reservoirenvironment, human
Metabolites

No metabolite relationships documented for this taxon.

Clinical Profile
Pathobiont
yes no context dependent unknown
Clinical Rolescommensal
Typical Specimenstool
Risk Contextsmelanoma patients receiving immune checkpoint inhibitor therapy (ICB)
Clinical Associations:
E2
E3 — Strong human clinical evidence E2 — Moderate human evidence E1 — Limited / preliminary
Klebsiella pneumoniae was among 8 commensal species significantly enriched in pre-treatment stool of metastatic melanoma anti-PD-1 responders (n=16) versus non-responders (n=26) by integrated 16S rRNA, shotgun metagenomic, and qPCR analysis (P<0.05, permutation test); it was part of a 10-species composite qPCR score significantly higher in responders (P=0.004).
PMID: 29302014
D007167 Immunotherapy D008545 Melanoma D061026 Programmed Cell Death 1 Receptor H00038 Melanoma
Last reviewed: 2026-04-03
Evidence Timeline
Related Taxa Shared Niche = same body site   Shared Risk = same vulnerable population