Vilanova-Cuevas Brayan, DeRito Christopher M, Ritchie Isabella T, Kellogg Christina A, Evans James S, Zimmerman Alizee, Williams Stacey M, Brandt Marilyn, Sevier Moriah, Gittens Samuel, Budd Kayla A, Warham Matthew, Sharp William C, Delgado Gabriel A, Hylkema Alwin, Kitson-Walters Kimani, Quod Jean-Pascal, Breitbart Mya, Hewson Ian
Department of Microbiology, Cornell University, Ithaca, New York, USA.
College of Marine Science, University of South, St. Petersburg, Florida, USA.
mSystems. 2025 Mar 18;10(3):e0141824. doi: 10.1128/msystems.01418-24. Epub 2025 Feb 19.
Mass mortality of Diadematidae urchins, caused by the scuticociliatosis Philaster clade (DScPc) affected the Caribbean in spring 2022 and subsequently spread to the eastern Mediterranean, Red Sea, and western Indian Ocean. A key question around Diadematidae scuticociliatosis (DSc), the disease caused by the scuticociliate, is whether the urchin microbiome varies between scuticociliatosis-affected and grossly normal urchins. Tissue samples from both grossly normal and abnormal were collected in the field during the initial assessment of the DSc causative agent and from an experimental challenge of DScPc culture on aquacultured . Specimens were analyzed using 16S rRNA gene amplicon sequencing. Additional abnormal urchin samples were collected from the most recent outbreak site in the western Indian Ocean (Réunion Island). At reference (i.e., unaffected by DSc) sites, spp. spp., and spp. were highly represented in amplicon libraries. DSc-affected urchin amplicon libraries had lower taxonomic richness and a greater representation of taxa related to and spp. Amplicon libraries of urchins experimentally challenged with the DSc pathogen had some shifts in microbial composition, but was not a part of the core bacteria in DSc-challenged specimens. DSc-affected from Réunion Island showed a similar high representation of as that seen on Caribbean . Our results suggest that DSc alters microbiomes and that may be a candidate bacterial biomarker for DSc in environmental samples. The mechanism driving microbiome variation in host-pathogen interactions remains to be explored.IMPORTANCEThe mass mortality of Diadematidae urchins due to scuticociliatosis (DSc) has had significant ecological impacts, spreading from the Caribbean to the eastern Mediterranean, Red Sea, and western Indian Ocean. This study investigates whether the microbiome of urchins varies between those affected by DSc and those that are not. Using 16S rRNA gene amplicon sequencing, researchers found that DSc-affected urchins had lower taxonomic richness and a greater representation of and spp. The findings indicate that could serve as a bacterial biomarker for DSc in environmental samples, providing a potential tool for early detection and management of the disease. Understanding these microbiome changes is crucial for developing strategies to mitigate the spread and impact of DSc on marine ecosystems.
由盾纤毛虫Philaster进化枝（DScPc）引起的冠海胆大量死亡事件于2022年春季影响了加勒比地区，随后蔓延至东地中海、红海和西印度洋。围绕由盾纤毛虫引起的疾病——冠海胆盾纤毛虫病（DSc）的一个关键问题是，受盾纤毛虫病影响的海胆与外观正常的海胆之间的微生物群是否存在差异。在对DSc病原体进行初步评估期间，从野外采集了外观正常和异常海胆的组织样本，并从对养殖海胆进行DScPc培养的实验性挑战中采集了样本。使用16S rRNA基因扩增子测序对样本进行分析。还从西印度洋（留尼汪岛）最近的疫情爆发地点采集了额外的异常海胆样本。在参考（即未受DSc影响）地点，弧菌属、芽孢杆菌属和假交替单胞菌属在扩增子文库中占比很高。受DSc影响的海胆扩增子文库的分类丰富度较低，与弧菌属和假交替单胞菌属相关的分类群占比更高。用DSc病原体进行实验性攻击的海胆的扩增子文库在微生物组成上有一些变化，但弧菌不是受DSc攻击的样本中的核心细菌之一。来自留尼汪岛的受DSc影响的海胆显示出与加勒比海胆相似的弧菌高占比情况。我们的结果表明，DSc会改变海胆微生物群，并且弧菌可能是环境样本中DSc的候选细菌生物标志物。宿主 - 病原体相互作用中驱动微生物群变化的机制仍有待探索。
由盾纤毛虫病（DSc）导致的冠海胆大量死亡对生态产生了重大影响，从加勒比地区蔓延到东地中海、红海和西印度洋。本研究调查了受DSc影响的海胆与未受影响的海胆之间的微生物群是否存在差异。研究人员通过16S rRNA基因扩增子测序发现，受DSc影响的海胆分类丰富度较低，弧菌属和假交替单胞菌属的占比更高。这些发现表明，弧菌可作为环境样本中DSc的细菌生物标志物，为该疾病的早期检测和管理提供了一种潜在工具。了解这些微生物群变化对于制定减轻DSc对海洋生态系统的传播和影响的策略至关重要。
