Department of Biology, San Diego State University, San Diego, 92182, USA.
Department of Oceanography and Sea Grant College Program, Center for Microbial Oceanography: Research and Education, University of Hawai'i at Mānoa, Honolulu, 96822, USA.
Nat Commun. 2019 Apr 12;10(1):1691. doi: 10.1038/s41467-019-09419-z.
On coral reefs, microorganisms are essential for recycling nutrients to primary producers through the remineralization of benthic-derived organic matter. Diel investigations of reef processes are required to holistically understand the functional roles of microbial players in these ecosystems. Here we report a metagenomic analysis characterizing microbial communities in the water column overlying 16 remote forereef sites over a diel cycle. Our results show that microbial community composition is more dissimilar between day and night samples collected from the same site than between day or night samples collected across geographically distant reefs. Diel community differentiation is largely driven by the flux of Psychrobacter sp., which is two-orders of magnitude more abundant during the day. Nighttime communities are enriched with species of Roseobacter, Halomonas, and Alteromonas encoding a greater variety of pathways for carbohydrate catabolism, further illustrating temporal patterns of energetic provisioning between different marine microbes. Dynamic diel fluctuations of microbial populations could also support the efficient trophic transfer of energy posited in coral reef food webs.
在珊瑚礁中，微生物通过底栖有机物质的再矿化将营养物质循环回收给初级生产者，这对它们来说是必不可少的。为了全面了解微生物在这些生态系统中的功能作用，需要对珊瑚礁过程进行昼夜调查。在这里，我们报告了一项宏基因组分析，该分析描述了在昼夜周期内覆盖 16 个偏远前礁点的水柱中的微生物群落。我们的研究结果表明，与从不同地理位置的珊瑚礁收集的昼夜样本相比，来自同一地点的昼夜样本之间的微生物群落组成差异更大。昼夜社区的分化主要是由 Psychrobacter sp. 的通量驱动的，该物质在白天的丰度要高出两个数量级。夜间群落富含 Roseobacter、Halomonas 和 Alteromonas 等物种，这些物种编码了更多的碳水化合物分解代谢途径，进一步说明了不同海洋微生物之间能量供应的时间模式。微生物种群的动态昼夜波动也可能支持在珊瑚礁食物网中提出的能量的有效营养转移。
