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

Cross-domain microbial cooperation in the bark beetle holobiont supports nutrient acquisition and metabolism, with metabolic complementarity observed among symbionts and host.

• Why it matters: Understanding how microbial symbiosis facilitates host adaptation remains limited, especially regarding metabolic integration and nutrient cycling within holobionts.
• What they did: Using metatranscriptomics, genomics, and metabolic assays, the study examined gut microbiome interactions in Ips typographus, revealing distributed pathways for nitrogen recycling, amino acid supply, vitamin co-metabolism, and carbohydrate degradation.
• The result: Findings suggest that microbial cooperation and functional redundancy underpin holobiont resilience and stability, with the bacteriome playing a key role, and imply that the host may contribute to lignocellulose processing.