Kellogg Christina A, Goldsmith Dawn B, Gray Michael A
St. Petersburg Coastal and Marine Science Center, United States Geological Survey, St. PetersburgFL, USA.
Front Microbiol. 2017 May 4;8:796. doi: 10.3389/fmicb.2017.00796. eCollection 2017.
Over the last decade, publications on deep-sea corals have tripled. Most attention has been paid to , a globally distributed scleractinian coral that creates critical three-dimensional habitat in the deep ocean. The bacterial community associated with has been previously described by a number of studies at sites in the Mediterranean Sea, Norwegian fjords, off Great Britain, and in the Gulf of Mexico (GOM). However, use of different methodologies prevents direct comparisons in most cases. Our objectives were to address intra-regional variation and to identify any conserved bacterial core community. We collected samples from three distinct colonies of at each of four locations within the western Atlantic: three sites within the GOM and one off the east coast of the United States. Amplicon libraries of 16S rRNA genes were generated using primers targeting the V4-V5 hypervariable region and 454 pyrosequencing. The dominant phylum was Proteobacteria (75-96%). At the family level, 80-95% of each sample was comprised of five groups: Pirellulaceae, Pseudonocardiaceae, Rhodobacteraceae, Sphingomonadaceae, and unclassified Oceanospirillales. Principal coordinate analysis based on weighted UniFrac distances showed a clear distinction between the GOM and Atlantic samples. Interestingly, the replicate samples from each location did not always cluster together, indicating there is not a strong site-specific influence. The core bacterial community, conserved in 100% of the samples, was dominated by the operational taxonomic units of genera and , both known degraders of aromatic hydrocarbons. The sequence of another core member, , was also found in prior studies of from Norway and Great Britain, suggesting a role as a conserved symbiont. By examining more than 40,000 sequences per sample, we found that GOM samples were dominated by the identified conserved core sequences, whereas open Atlantic samples had a much higher proportion of locally consistent bacteria. Further, predictive functional profiling highlights the potential for the microbiome to contribute to chemoautotrophy, nutrient cycling, and antibiotic production.
在过去十年中，关于深海珊瑚的出版物数量增长了两倍。大部分注意力都集中在 ，一种全球分布的石珊瑚，它在深海中创造了关键的三维栖息地。此前，在地中海、挪威峡湾、英国近海和墨西哥湾（GOM）的多个地点，已有多项研究描述了与 相关的细菌群落。然而，在大多数情况下，不同方法的使用阻碍了直接比较。我们的目标是解决区域内变异问题，并识别任何保守的细菌核心群落。我们从西大西洋四个地点的三个不同的 群体中采集了样本：墨西哥湾内的三个地点和美国东海岸外的一个地点。使用靶向V4 - V5高变区的引物和454焦磷酸测序技术生成了16S rRNA基因的扩增子文库。优势菌门是变形菌门（75 - 96%）。在科水平上，每个样本的80 - 95%由五组组成：皮氏菌科、假诺卡氏菌科、红杆菌科、鞘脂单胞菌科和未分类的海洋螺菌目。基于加权UniFrac距离的主坐标分析显示，墨西哥湾和大西洋样本之间有明显区别。有趣的是，每个地点的重复样本并不总是聚集在一起，这表明不存在强烈的位点特异性影响。在100%的样本中都保守存在的核心细菌群落，主要由 属和 属的操作分类单元主导，这两个属都是已知的芳香烃降解菌。另一个核心成员 的序列也在之前挪威和英国的 研究中被发现，这表明它作为一种保守共生体的作用。通过检查每个样本超过40000个序列，我们发现墨西哥湾样本以已识别的保守核心序列为主，而开阔大西洋样本中本地一致的细菌比例要高得多。此外，预测功能分析突出了 微生物组在化学自养、营养循环和抗生素生产方面的潜力。
