Endosymbionts of Metazoans Dwelling in the PACManus Hydrothermal Vent: Diversity and Potential Adaptive Features Revealed by Genome Analysis.
Endosymbionts of Metazoans Dwelling in the PACManus Hydrothermal Vent: Diversity and Potential Adaptive Features Revealed by Genome Analysis.
复制标题
居住在 PACManus 热液喷口的后生动物的内共生体：基因组分析揭示的多样性和潜在的适应性特征
DOI：
10.1128/aem.00815-20
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发表时间：
2020-10-15
影响因子：
4.4
通讯作者：
Li C
中科院分区：
文献类型：
--
作者：
Li L;Wang M;Li L;Du Z;Sun Y;Wang X;Zhang X;Li C
深海热液喷口以若干无脊椎动物物种为主。长期以来，共生关系的建立一直被认为是这些定居物种在如此恶劣的环境中成功殖民的关键。然而，共生细菌与其宿主之间的关系及其在环境适应中的作用通常仍不清楚。在本文中，我们表明，三个主机种的分布显示特征生态位划分在马努斯盆地，让我们有机会了解他们如何适应自己的特定栖息地。本研究还揭示了三个新的共生体的基因组从蜗牛的A。布凯蒂结合其他外共生体和自由生活的细菌的数据集，蜗牛内共生体的基因组比较指出了几个可能导致Epsilonproteobacteria进入上皮细胞的生活方式转变的遗传特征。这些发现可以增加我们对深海生态系统中无脊椎动物-内共生体关系的理解。摘要深海热液喷口群落以无脊椎动物为主，即深海贝类、管虫和蜗牛。共生被认为是这些定居物种在这种极端环境中成功殖民的关键。在PACManus喷口区，蜗牛、管虫和贻贝各自占据了一个具有独特地球化学特征的生态位。为了更好地了解代谢潜力和基因组特征有助于宿主环境适应，我们比较了在PACManus采样的Bathyodiolus manusensis，Arcovestia ivanovi和Alviniconcha boucheti的共生体的基因组，并讨论了它们的环境适应性特征。我们找到了那个B。manusensis和A. ivanovi由来自不同分支的γ-变形菌定殖，而B的内共生体。manusensis具有高度的种内异质性，具有不同的代谢潜力。A. boucheti窝藏三个新的Epsilonproteobacteria共生体，这表明蜗牛共生体的潜在物种水平的多样性。基因组比较显示，与低pH稳态，金属抗性，抗氧化应激，环境感知/反应，趋化性和运动性相关的基因家族的相对丰度在A中最高。ivanovi的共生体，其次是喷口蜗牛A的共生体。boucheti，而相对较低的共生体的喷口周边居住贻贝B。manusensis，这与它们的环境适应和宿主-共生体相互作用是一致的。分类为编码宿主相互作用/附件，毒力因子/毒素，真核生物样蛋白的基因家族是最丰富的贻贝共生体和最不丰富的蜗牛，这表明这些共生体可能不同的主机殖民策略。通过比较Epsilonproteobacteria共生菌和非共生菌，发现共生菌中扩展的基因家族与维生素B12合成、毒素-抗毒素系统、甲基化和脂多糖生物合成有关，这表明这些基因家族对Epsilonproteobacteria共生菌的建立和发育至关重要。深海热液喷口主要由几种无脊椎动物物种组成。长期以来，共生关系的建立一直被认为是这些定居物种在如此恶劣的环境中成功殖民的关键。然而，共生细菌与其宿主之间的关系及其在环境适应中的作用通常仍不清楚。在本文中，我们表明，三个主机种的分布显示特征生态位划分在马努斯盆地，让我们有机会了解他们如何适应自己的特定栖息地。本研究还揭示了三个新的共生体的基因组从蜗牛的A。布凯蒂结合其他外共生体和自由生活的细菌的数据集，蜗牛内共生体的基因组比较指出了几个可能导致Epsilonproteobacteria进入上皮细胞的生活方式转变的遗传特征。这些发现可以增加我们对深海生态系统中无脊椎动物-内共生体关系的理解。
Deep-sea hydrothermal vents are dominated by several invertebrate species. The establishment of symbiosis has long been thought to be the key to successful colonization by these sedentary species in such harsh environments. However, the relationships between symbiotic bacteria and their hosts and their role in environmental adaptations generally remain unclear. In this paper, we show that the distribution of three host species showed characteristic niche partitioning in the Manus Basin, giving us the opportunity to understand how they adapt to their particular habitats. This study also revealed three novel genomes of symbionts from the snails of A. boucheti. Combined with a data set on other ectosymbiont and free-living bacteria, genome comparisons for the snail endosymbionts pointed to several genetic traits that may have contributed to the lifestyle shift of Epsilonproteobacteria into the epithelial cells. These findings could increase our understanding of invertebrate-endosymbiont relationships in deep-sea ecosystems. ABSTRACT Deep-sea hydrothermal vent communities are dominated by invertebrates, namely, bathymodiolin mussels, siboglinid tubeworms, and provannid snails. Symbiosis is considered key to successful colonization by these sedentary species in such extreme environments. In the PACManus vent fields, snails, tubeworms, and mussels each colonized a niche with distinct geochemical characteristics. To better understand the metabolic potentials and genomic features contributing to host-environment adaptation, we compared the genomes of the symbionts of Bathymodiolus manusensis, Arcovestia ivanovi, and Alviniconcha boucheti sampled at PACManus, and we discuss their environmentally adaptive features. We found that B. manusensis and A. ivanovi are colonized by Gammaproteobacteria from distinct clades, whereas endosymbionts of B. manusensis feature high intraspecific heterogeneity with differing metabolic potentials. A. boucheti harbored three novel Epsilonproteobacteria symbionts, suggesting potential species-level diversity of snail symbionts. Genome comparisons revealed that the relative abundance of gene families related to low-pH homeostasis, metal resistance, oxidative stress resistance, environmental sensing/responses, and chemotaxis and motility was the highest in A. ivanovi’s symbiont, followed by symbionts of the vent-mouth-dwelling snail A. boucheti, and was relatively low in the symbiont of the vent-periphery-dwelling mussel B. manusensis, which is consistent with their environmental adaptations and host-symbiont interactions. Gene families classified as encoding host interaction/attachment, virulence factors/toxins, and eukaryotic-like proteins were most abundant in symbionts of mussels and least abundant in those of snails, indicating that these symbionts may differ in their host colonization strategies. Comparison of Epsilonproteobacteria symbionts to nonsymbionts demonstrated that the expanded gene families in symbionts were related to vitamin B12 synthesis, toxin-antitoxin systems, methylation, and lipopolysaccharide biosynthesis, suggesting that these are vital to symbiont establishment and development in Epsilonproteobacteria. IMPORTANCE Deep-sea hydrothermal vents are dominated by several invertebrate species. The establishment of symbiosis has long been thought to be the key to successful colonization by these sedentary species in such harsh environments. However, the relationships between symbiotic bacteria and their hosts and their role in environmental adaptations generally remain unclear. In this paper, we show that the distribution of three host species showed characteristic niche partitioning in the Manus Basin, giving us the opportunity to understand how they adapt to their particular habitats. This study also revealed three novel genomes of symbionts from the snails of A. boucheti. Combined with a data set on other ectosymbiont and free-living bacteria, genome comparisons for the snail endosymbionts pointed to several genetic traits that may have contributed to the lifestyle shift of Epsilonproteobacteria into the epithelial cells. These findings could increase our understanding of invertebrate-endosymbiont relationships in deep-sea ecosystems.
影响因子：
4.4
作者：
Reingold V;Luria N;Robichon A;Dombrovsky A
通讯作者：
Dombrovsky A