Lee Won-Kyung, Juniper S Kim, Perez Maëva, Ju Se-Jong, Kim Se-Joo
Genome Editing Research Center Korea Research Institute of Bioscience and Biotechnology Daejeon Korea.
Department of Biology School of Earth and Ocean Sciences University of Victoria Victoria BC Canada.
Ecol Evol. 2021 Mar 10;11(9):4481-4493. doi: 10.1002/ece3.7343. eCollection 2021 May.
Host-symbiont relationships in hydrothermal vent ecosystems, supported by chemoautotrophic bacteria as primary producers, have been extensively studied. However, the process by which densely populated co-occurring invertebrate hosts form symbiotic relationships with bacterial symbionts remains unclear. Here, we analyzed gill-associated symbiotic bacteria (gill symbionts) of five co-occurring hosts, three mollusks ("" , . , and ) and two crustaceans ( and ), collected together at a single vent site in the Tonga Arc. We observed both different compositions of gill symbionts and the presence of unshared operational taxonomic units (OTUs). In addition, the total number of OTUs was greater for crustacean hosts than for mollusks. The phylogenetic relationship trees of gill symbionts suggest that γ-proteobacterial gill symbionts have coevolved with their hosts toward reinforcement of host specificity, while campylobacterial species found across various hosts and habitats are opportunistic associates. Our results confirm that gill symbiont communities differ among co-occurring vent invertebrates and indicate that hosts are closely related with their gill symbiont communities. Considering the given resources available at a single site, differentiation of gill symbionts seems to be a useful strategy for obtaining nutrition and energy while avoiding competition among both hosts and gill symbionts.
以化能自养细菌作为主要生产者的热液喷口生态系统中的宿主 - 共生体关系已得到广泛研究。然而，大量共生的无脊椎动物宿主与细菌共生体形成共生关系的过程仍不清楚。在此，我们分析了在汤加弧的一个单一喷口位点共同采集的五种共生宿主（三种软体动物：[具体三种软体动物名称未给出]、[具体三种软体动物名称未给出]和[具体三种软体动物名称未给出]，以及两种甲壳类动物：[具体两种甲壳类动物名称未给出]和[具体两种甲壳类动物名称未给出]）的鳃相关共生细菌（鳃共生体）。我们观察到鳃共生体的不同组成以及未共享的可操作分类单元（OTU）的存在。此外，甲壳类宿主的OTU总数比软体动物的更多。鳃共生体的系统发育关系树表明，γ - 变形菌纲的鳃共生体与其宿主共同进化以增强宿主特异性，而在各种宿主和栖息地中发现的弯曲杆菌属物种是机会性共生体。我们的结果证实，共生的喷口无脊椎动物的鳃共生体群落存在差异，并表明宿主与其鳃共生体群落密切相关。考虑到单个位点的可用资源，鳃共生体的分化似乎是在避免宿主和鳃共生体之间竞争的同时获取营养和能量的有用策略。
