Phycosphere microbiome contributes to ecological dominance of diatoms: a comparative study ofand
Source: PubMed Central Open Access, NCBI / U.S. National Library of Medicine
Abstract Diatoms play a crucial role in aquatic ecosystems, yet the mechanisms underlying their long-term dominance remain poorly understood. This study investigated the relationship between diatom ecological persistence and their phycosphere bacterial communities by comparing the long-term dominant specieswith the short-term dominant species. 16S rRNA gene sequencing combined with predictive functional profiling revealed that the bacterial community associated withwas more diverse, stable, and interconnected than that associated with. Taxonomic analysis identified key bacterial taxa such as,, andenriched in. Co-occurrence network analysis demonstrated higher microbial interaction complexity in, enhancing functional redundancy and ecosystem stability. Functional predictions indicated significant enrichment in carbohydrate metabolism (glycosaminoglycan degradation, pentose/glucose interconversion) and stress response pathways (betaine biosynthesis, xenobiotic metabolism by cytochrome P450) in themicrobiome, supporting a mutualistic relationship in which diatom-derived extracellular polymeric substances sustains specialized bacteria that reciprocate with vitamin B, phytohormones, and chemical defenses. Based on these results, a mutually reinforced symbiotic cycle model was proposed to illustrate how the diatom and its phycosphere microbiome established a resilient holobiont capable of prolonged ecological dominance. The bacterial community associated with each diatom species ex
Abstract
Abstract Diatoms play a crucial role in aquatic ecosystems, yet the mechanisms underlying their long-term dominance remain poorly understood. This study investigated the relationship between diatom ecological persistence and their phycosphere bacterial communities by comparing the long-term dominant specieswith the short-term dominant species. 16S rRNA gene sequencing combined with predictive functional profiling revealed that the bacterial community associated withwas more diverse, stable, and interconnected than that associated with. Taxonomic analysis identified key bacterial taxa such as,, andenriched in. Co-occurrence network analysis demonstrated higher microbial interaction complexity in, enhancing functional redundancy and ecosystem stability. Functional predictions indicated significant enrichment in carbohydrate metabolism (glycosaminoglycan degradation, pentose/glucose interconversion) and stress response pathways (betaine biosynthesis, xenobiotic metabolism by cytochrome P450) in themicrobiome, supporting a mutualistic relationship in which diatom-derived extracellular polymeric substances sustains specialized bacteria that reciprocate with vitamin B, phytohormones, and chemical defenses. Based on these results, a mutually reinforced symbiotic cycle model was proposed to illustrate how the diatom and its phycosphere microbiome established a resilient holobiont capable of prolonged ecological dominance. The bacterial community associated with each diatom species exhibited host specificity and contributed to the maintenance of host dominance. These findings highlight the critical role of microbial partnerships in diatom success, offering new insights for predicting phytoplankton community dynamics and managing aquatic ecosystems.