Department of Marine Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
Department of Biology, Boston University, Boston, MA, USA.
Mol Ecol. 2020 Jul;29(13):2334-2348. doi: 10.1111/mec.15497. Epub 2020 Jul 11.
A coral's capacity to alter its microbial symbionts may enhance its fitness in the face of climate change. Recent work predicts exposure to high environmental variability may increase coral resilience and adaptability to future climate conditions. However, how this heightened environmental variability impacts coral-associated microbial communities remains largely unexplored. Here, we examined the bacterial and algal symbionts associated with two coral species of the genus Siderastrea with distinct life history strategies from three reef sites on the Belize Mesoamerican Barrier Reef System with low or high environmental variability. Our results reveal bacterial community structure, as well as alpha- and beta-diversity patterns, vary by host species. Differences in bacterial communities between host species were partially explained by high abundance of Deltaproteobacteria and Rhodospirillales and high bacterial diversity in Siderastrea radians. Our findings also suggest Siderastrea spp. have dynamic core bacterial communities that likely drive differences observed in the entire bacterial community, which may play a critical role in rapid acclimatization to environmental change. Unlike the bacterial community, Symbiodiniaceae composition was only distinct between host species at high thermal variability sites, suggesting that different factors shape bacterial versus algal communities within the coral holobiont. Our findings shed light on how domain-specific shifts in dynamic microbiomes may allow for unique methods of enhanced host fitness.
珊瑚改变其微生物共生体的能力可能会增强其在气候变化面前的适应能力。最近的研究预测，暴露在高度环境变异性下可能会增加珊瑚的弹性和对未来气候条件的适应能力。然而，这种增强的环境变异性如何影响珊瑚相关的微生物群落在很大程度上仍未得到探索。在这里，我们研究了来自伯利兹中美洲堡礁系统的三个珊瑚礁地点的两种 Siderastrea 属珊瑚的细菌和藻类共生体，这些地点的环境变异性低或高。我们的结果表明，细菌群落结构以及 alpha 和 beta 多样性模式因宿主物种而异。宿主物种之间细菌群落的差异部分归因于 Deltaproteobacteria 和 Rhodospirillales 的高丰度以及 Siderastrea radians 的高细菌多样性。我们的研究结果还表明，Siderastrea spp. 具有动态核心细菌群落，这些群落可能在整个细菌群落中产生差异，这可能在快速适应环境变化方面发挥关键作用。与细菌群落不同的是，Symbiodiniaceae 组成仅在高温度变异性地点的宿主物种之间存在差异，这表明不同的因素塑造了珊瑚共生体中的细菌和藻类群落。我们的研究结果揭示了动态微生物组中特定领域的变化如何为增强宿主适应性提供独特的方法。
