Department of Biology, College of Charleston, Charleston, South Carolina, USA.
Department of Biology, Grice Marine Lab, College of Charleston, Charleston, South Carolina, USA.
mSphere. 2021 Oct 27;6(5):e0066521. doi: 10.1128/mSphere.00665-21. Epub 2021 Sep 22.
The ocean represents the largest biome on earth; however, we have only begun to understand the diversity and function of the marine microbial inhabitants and their interactions with macroalgal species. Macroalgae play an integral role in overall ocean biome health and serve both as major primary producers and foundation species in the ecosystem. Previous studies have been limited, focusing on the microbiome of a single algal species or its interaction with selected microbes. This project aimed to understand overall biodiversity of microbial communities associated with five common macroalgal species and to determine the drivers of these communities at 'Ewa Beach, O'ahu, HI. Representative species of Chlorophyta (green), Ochrophyta (brown), and Rhodophyta (red) algae, each species having various levels of calcification, thallus complexity, and status as native or invasive species, were collected from an intertidal bench in May 2019. A portion of the V3-V4 variable region of the small-subunit rRNA gene was amplified for high-throughput sequencing using universal bacterial primers to elucidate the core and variable algal microbiome. Significant differences in bacterial community composition were only partially explained by host species, whether the host was native or invasive, and thallus complexity. Macroalgal phylum explained the most variation in associated microbial communities at 'Ewa Beach. This study advances our understanding of microbial-macroalgal interactions and their connectivity by producing insight into factors that influence the community structure of macroalga-associated microbiota. Generally, most eukaryotic organisms form relationships with microbes that are important in mediating host organismal health. Macroalgae are a diverse group of photosynthetic eukaryotic organisms that serve as primary producers and foundational species in many ecosystems. However, little is known about their microbial counterparts across a wide range of macroalgal morphologies, phylogenies, and calcification levels. Thus, to further understand the factors involved in bacterial community composition associated with macroalgal species at one point in time, representative samples were collected across phyla. Here, we show that both host macroalga phyla and morphology influenced the associated microbial community. Additionally, we show that the invasive species Avrainvillea lacerata does not have a unique microbial community on this intertidal bench, further supporting the idea that host phylum strongly influences microbial community composition.
海洋是地球上最大的生物群落，但我们才刚刚开始了解海洋微生物居民的多样性和功能，以及它们与大型藻类物种的相互作用。大型藻类在海洋生物群落的整体健康中起着至关重要的作用，既是主要的初级生产者，也是生态系统的基础物种。以前的研究受到限制，主要集中在单一藻类物种的微生物组或其与选定微生物的相互作用。本项目旨在了解与五种常见大型藻类物种相关的微生物群落的总体生物多样性，并确定这些群落的驱动因素。在夏威夷欧湖岛的 Ewa Beach，从 2019 年 5 月的潮间带长凳上采集了代表绿藻（Chlorophyta）、褐藻（Ochrophyta）和红藻（Rhodophyta）的代表物种，每个物种的钙化程度、藻体复杂性以及是否为本地或入侵物种各不相同。使用通用细菌引物对小亚基 rRNA 基因的 V3-V4 可变区进行扩增，进行高通量测序，以阐明核心和可变藻类微生物组。细菌群落组成的显著差异仅部分由宿主物种（本地或入侵）和藻体复杂性来解释。大型藻类门解释了在 Ewa Beach 影响与大型藻类相关的微生物群落的最大变化。这项研究通过深入了解影响大型藻类相关微生物群落结构的因素，推进了我们对微生物-大型藻类相互作用及其连通性的理解。一般来说，大多数真核生物与微生物形成关系，这些关系对调节宿主生物的健康很重要。大型藻类是一组多样化的光合真核生物，它们是许多生态系统中的主要生产者和基础物种。然而，对于广泛的大型藻类形态、系统发育和钙化水平，人们对其微生物对应物知之甚少。因此，为了进一步了解与大型藻类物种在某一时间点相关的细菌群落组成所涉及的因素，跨门收集了代表性样本。在这里，我们表明宿主大型藻类门和形态都影响了相关的微生物群落。此外，我们还表明，入侵物种 Avrainvillea lacerata 在这个潮间带长凳上并没有独特的微生物群落，这进一步支持了宿主门强烈影响微生物群落组成的观点。
