Iron-dependent metabolic rewiring drives tryptophan-associated melanin production in a clinical Pseudomonas aeruginosa strain.

Iron-dependent metabolic rewiring enables Pseudomonas aeruginosa to produce a novel tryptophan-associated melanin-like pigment, supporting iron acquisition during infection.

• Why it matters: Understanding how P. aeruginosa adapts metabolically to hostile environments like the human host is crucial for developing strategies to combat persistent infections. This study addresses the gap in knowledge about melanin production pathways beyond pyomelanin in P. aeruginosa.
• What they did: The researchers used a multi-omics approach—including structural, genomic, transcriptomic, and metabolomic analyses—on a clinical strain, revealing the production of a tryptophan-derived melanin-like pigment linked to iron homeostasis and genetic mutations affecting iron acquisition systems.
• The result: Findings demonstrate that iron limitation promotes this pigment's production, which may aid bacterial survival, expanding the known diversity of bacterial melanins and highlighting metabolic flexibility during infection.