Fungal diversity in deep-sea sediments associated with asphalt seeps at the Sao Paulo Plateau
Fungal diversity in deep-sea sediments associated with asphalt seeps at the Sao Paulo Plateau
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DOI：
10.1016/j.dsr2.2017.05.012
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发表时间：
2017-12-01
影响因子：
3
通讯作者：
Fujikura, Katsunori
中科院分区：
文献类型：
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作者：
Nagano, Yuriko;Miura, Toshiko;Fujikura, Katsunori
采用离子激流PGM技术，对巴西圣保罗高原两个不同地点采集的20份深海沉积物样品（其中14份与天然沥青渗漏有关，6份与天然沥青渗漏无关）中的真菌多样性进行了研究。结果表明，圣保罗高原深海沉积物样品中存在多种真菌（基于97%序列相似性聚类的113个操作分类单元（OTUs），分为9类31属），以子囊菌门（74.3%）为主，其次是担子菌门（11.5%），未知真菌（7.1%），与公共数据库中任何生物都没有关联的序列（7.1%）。结果表明，该地区的主要优势种为青霉菌（Penicillium sp.）、紫花椒（Cadophora malorum）和薯蓣红孢子菌（Rhodosporidiwn diobovatum） 3种，大部分OTUs仍为小型群落。出乎意料的是，沥青渗漏点和非沥青渗漏点之间的主要真菌群落结构没有显著差异，尽管沥青渗漏点周围存在大量的碳氢化合物沉积物和大量的宏观生物。然而，在较小的真菌群落中存在一些差异，可能的沥青降解真菌专门存在于沥青渗漏点。相比之下，在两个不同的采样点之间发现了一些差异。对真菌otu的分类显示，与公共数据库中已有的ITS序列相比，只有47个（41.6%）真菌otu序列相似性为0.97%，这表明大多数深海栖息真菌分类群仍未被描述。尽管我们对真菌及其在深海环境中的作用的认识仍然有限和稀缺，但这项研究增加了我们对深海环境中真菌多样性和群落结构的了解。
We investigated the fungal diversity in a total of 20 deep-sea sediment samples (of which 14 samples were associated with natural asphalt seeps and 6 samples were not associated) collected from two different sites at the Sao Paulo Plateau off Brazil by Ion Torrent PGM targeting ITS region of ribosomal RNA. Our results suggest that diverse fungi (113 operational taxonomic units (OTUs) based on clustering at 97% sequence similarity assigned into 9 classes and 31 genus) are present in deep-sea sediment samples collected at the Sao Paulo Plateau, dominated by Ascomycota (74.3%), followed by Basidiomycota (11.5%), unidentified fungi (7.1%), and sequences with no affiliation to any organisms in the public database (7.1%). However, it was revealed that only three species, namely Penicillium sp., Cadophora malorum and Rhodosporidiwn diobovatum, were dominant, with the majority of OTUs remaining a minor community. Unexpectedly, there was no significant difference in major fungal community structure between the asphalt seep and non-asphalt seep sites, despite the presence of mass hydrocarbon deposits and the high amount of macro organisms surrounding the asphalt seeps. However, there were some differences in the minor fungal communities, with possible asphalt degrading fungi present specifically in the asphalt seep sites. In contrast, some differences were found between the two different sampling sites. Classification of OTUs revealed that only 47 (41.6%) fungal OTUs exhibited >97% sequence similarity, in comparison with pre-existing ITS sequences in public databases, indicating that a majority of deep-sea inhabiting fungal taxa still remain undescribed. Although our knowledge on fungi and their role in deep-sea environments is still limited and scarce, this study increases our understanding of fungal diversity and community structure in deep-sea environments.