Epiphytic and endophytic microbiome of the seagrass Zostera marina: Do they contribute to pathogen reduction in seawater?

作者：D. Taşdemir, S. Scarpato, Caroline Utermann-Thüsing, Timo Jensen, M. Blümel, A. Wenzel-Storjohann, Claudia Welsch, Vivien A Echelmeyer · 发表于：bioRxiv · 年份：2023 · DOI：10.1101/2023.08.21.554113 · 被引用次数：34 · 研究领域：Medicine、Biology

Seagrass ecosystems provide crucial ecosystem services for coastal environments and were shown to reduce the abundance of pathogens linked to infections in humans and marine organisms. Among several potential drivers, seagrass phenolics released into seawater have been suggested to play role in pathogen suppression, but the potential involvement of the seagrass microbiome in such effect has not been studied. Here we hypothesized that the microbiome of the eelgrass Zostera marina, especially the leaf epiphytes that are at direct interface between the seagrass host and surrounding seawater, inhibit such pathogenic microorganisms, hence, contribute to their suppression. Using a culture-dependent approach, we isolated 88 bacteria and fungi associated with the surfaces and inner tissues of the eelgrass leaves (healthy and decaying) and the roots, plus 19 strains from surrounding seawater and sediment. We first assessed the broad-spectrum antibiotic activity of microbial extracts against a large panel of common aquatic, human (fecal) and plant pathogens, and finally mined the metabolome of 88 most active extracts. The healthy leaf epibiotic bacteria, particularly Streptomyces sp. strain 131, displayed broad-spectrum and potent antibiotic activity superior to some control drugs. Gram-negative bacteria abundant on healthy leaf surfaces, and few endosphere-associated bacteria and fungi also showed remarkable antimicrobial activity. UPLC-MS/MS-based massive untargeted metabolomics anal...