Cross-domain cooperation drives nutrient acquisition and metabolism in the bark beetle holobiont.

Cross-domain microbial cooperation enables nutrient acquisition and metabolism in the Ips typographus bark beetle holobiont, with key roles for bacteria, fungi, and host.

• Why it matters: Understanding how microbial symbiosis supports host adaptation is crucial for revealing mechanisms of metabolic integration and resilience in complex holobionts, which has implications for ecosystem nutrient cycling.
• What they did: Using metatranscriptomics, genomics, and metabolic assays, the study examined gut microbiome interactions, revealing distributed pathways for nitrogen recycling, carbohydrate breakdown, and vitamin synthesis across bacteria, fungi, and the beetle.
• The result: The findings demonstrate that metabolic interdependence, rather than microbial composition alone, sustains holobiont function, highlighting microbial cooperation's role in ecological resilience and host nutrient processing.