Genome wide analysis of Priestia aryabhattai_OP, an endobacterium, modulating growth, development and biochemical compositions of sporophores in edible oyster mushroom Pleurotus ostreatus (MTCC 1802).

The increasing global interest in the consuming and producing of edible oyster mushrooms (Pleurotus spp.) is driven by their well-documented nutritional and health benefits. The metagenomic analysis of fruiting body revealed a distinct microbial composition in P. ostreatus, predominantly comprising Pseudomonodota (~ 82%) and Bacillota (~ 10%). An endobacterium Priestia aryabhattai_OP, associated with internal tissue of P. ostreatus (MTCC 1802), was isolated and characterized through biochemical and microscopic analyses as well as 16 S rRNA and whole genome sequencing. Co-cultivation of P. ostreatus with this bacterium significantly enhanced the in vitro production of laccase, a key growth-promoting enzyme. Additionally, the endobacterium improved the biological efficiency (BE) of the mushroom, enriched its nutraceutical profile, and facilitated the biosynthesis of beneficial compounds, including IAA, siderophores, and antimicrobials like lassopeptides, phosphonates, non-ribosomal iron-binding siderophores (NI- siderophore), carotenoids, paeninodins, synechobactins, and surfactins. The present findings offer novel insights into microbe-microbe interactions and their pivotal roles in fungal biology, with significant implications for sustainable mushroom production as well as nutrient enrichment and biotechnological advancements.