Weigel Brooke L, Erwin Patrick M
Department of Biology and Marine Biology, Center for Marine Science, University of North Carolina Wilmington, Wilmington, North Carolina, USA.
Department of Biology and Marine Biology, Center for Marine Science, University of North Carolina Wilmington, Wilmington, North Carolina, USA
Appl Environ Microbiol. 2015 Nov 13;82(2):650-8. doi: 10.1128/AEM.02980-15. Print 2016 Jan 15.
Sponges host diverse and complex communities of microbial symbionts that display a high degree of host specificity. The microbiomes of conspecific sponges are relatively constant, even across distant locations, yet few studies have directly examined the influence of abiotic factors on intraspecific variation in sponge microbial community structure. The contrast between intertidal and subtidal environments is an ideal system to assess the effect of environmental variation on sponge-microbe symbioses, producing two drastically different environments on a small spatial scale. Here, we characterized the microbial communities of individual intertidal and subtidal Hymeniacidon heliophila sponges, ambient seawater, and sediment from a North Carolina oyster reef habitat by partial (Illumina sequencing) and nearly full-length (clone libraries) 16S rRNA gene sequence analyses. Clone library sequences were compared to H. heliophila symbiont communities from the Gulf of Mexico and Brazil, revealing strong host specificity of dominant symbiont taxa across expansive geographic distances. Sediment and seawater samples yielded clearly distinct microbial communities from those found in H. heliophila. Despite the close proximity of the sponges sampled, significant differences between subtidal and intertidal sponges in the diversity, structure, and composition of their microbial communities were detected. Differences were driven by changes in the relative abundance of a few dominant microbial symbiont taxa, as well as the presence or absence of numerous rare microbial taxa. These findings suggest that extreme abiotic fluctuations, such as periodic air exposure in intertidal habitats, can drive intraspecific differences in complex host-microbe symbioses.
海绵动物宿主着多样且复杂的微生物共生体群落，这些共生体表现出高度的宿主特异性。同种海绵动物的微生物群落相对稳定，即使分布在遥远的地点，但很少有研究直接考察非生物因素对海绵动物微生物群落结构种内变异的影响。潮间带和潮下带环境之间的差异是评估环境变异对海绵 - 微生物共生关系影响的理想系统，在小空间尺度上产生了两种截然不同的环境。在这里，我们通过部分（Illumina测序）和近乎全长（克隆文库）16S rRNA基因序列分析，对来自北卡罗来纳牡蛎礁栖息地的潮间带和潮下带嗜阳 Hymeniacidon heliophila 海绵个体、周围海水和沉积物中的微生物群落进行了表征。将克隆文库序列与来自墨西哥湾和巴西的嗜阳 Hymeniacidon heliophila 共生体群落进行比较，发现在广阔的地理距离上，优势共生分类群具有很强的宿主特异性。沉积物和海水样本产生的微生物群落与嗜阳 Hymeniacidon heliophila 中的明显不同。尽管所采样的海绵距离很近，但仍检测到潮下带和潮间带海绵在微生物群落的多样性、结构和组成方面存在显著差异。差异是由少数优势微生物共生分类群相对丰度的变化以及众多稀有微生物分类群的存在与否所驱动的。这些发现表明，极端的非生物波动，如潮间带栖息地的周期性空气暴露，可导致复杂宿主 - 微生物共生关系中的种内差异。
