Diversity and identification of methanogenic archaea and sulphate-reducing bacteria in sediments from a pristine tropical mangrove
Diversity and identification of methanogenic archaea and sulphate-reducing bacteria in sediments from a pristine tropical mangrove
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DOI：
10.1007/s10482-010-9422-8
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发表时间：
2010-02
期刊：
影响因子：
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通讯作者：
R. G. Taketani;Caio A. Yoshiura;A. C. F. Dias;F. D. Andreote;S. Tsai
中科院分区：
文献类型：
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作者：
R. G. Taketani;Caio A. Yoshiura;A. C. F. Dias;F. D. Andreote;S. Tsai
红树林沉积物是一种富含有机质的厌氧生态系统。这种环境对于厌氧微生物是最佳的，例如硫酸盐还原菌和产甲烷古菌，它们负责营养循环。在这项研究中，这两个功能团的多样性在原始红树林采用变性梯度凝胶电泳（DGGE）和克隆文库测序在50厘米垂直剖面每5.0厘米取样。DGGE图谱表明，这两个群体在浅层样品（0-30厘米）中呈现出较高的丰富度，超过该深度，丰富度急剧下降。根据冗余度分析，这种变化与有机质含量的减少显著相关。克隆文库测序表明，深度对异化硫酸还原酶（dsrB）操作分类单位（OTU）的选择有很强的影响，如在浅（0.0 cm）和深（40.0 cm）文库中发现的少量共享OTU所示。另一方面，甲基辅酶-M还原酶（mcrA）文库表明，在浅文库中发现的大多数OTU存在于深文库中。结果表明，这两种功能团共存于这些红树林沉积物中，并表明这些生物在该生态系统的营养循环中的重要作用。
Mangrove sediments are anaerobic ecosystems rich in organic matter. This environment is optimal for anaerobic microorganisms, such as sulphate-reducing bacteria and methanogenic archaea, which are responsible for nutrient cycling. In this study, the diversity of these two functional guilds was evaluated in a pristine mangrove forest using denaturing gradient gel electrophoresis (DGGE) and clone library sequencing in a 50 cm vertical profile sampled every 5.0 cm. DGGE profiles indicated that both groups presented higher richness in shallow samples (0–30 cm) with a steep decrease in richness beyond that depth. According to redundancy analysis, this alteration significantly correlated with a decrease in the amount of organic matter. Clone library sequencing indicated that depth had a strong effect on the selection of dissimilatory sulphate reductase (dsrB) operational taxonomic units (OTUs), as indicated by the small number of shared OTUs found in shallow (0.0 cm) and deep (40.0 cm) libraries. On the other hand, methyl coenzyme-M reductase (mcrA) libraries indicated that most of the OTUs found in the shallow library were present in the deep library. These results show that these two guilds co-exist in these mangrove sediments and indicate important roles for these organisms in nutrient cycling within this ecosystem.