Toyama D, Santos-Júnior C D, Kishi L T, Oliveira T C S, Garcia J W, Sarmento H, Miranda F P, Henrique-Silva F
Laboratório de Biologia Molecular, Departamento de Genética e Evolução, , , Brasil.
Departamento de Química, , , Brasil.
Genet Mol Res. 2017 May 18;16(2):gmr-16-02-gmr.16029567. doi: 10.4238/gmr16029567.
The Amazon region has the largest hydrographic basin on the planet and is well known for its huge biodiversity of plants and animals. However, there is a lack of studies on aquatic microbial biodiversity in the Solimões River, one of its main water courses. To investigate the microbial biodiversity of this region, we performed 16S rRNA gene clone libraries from Solimões River and adjacent rivers and lakes. Our question was which microorganisms inhabit the different types of aquatic environments in this part of the basin, and how diversity varies among these environments (rivers and lakes). The microbial diversity generating 13 clone libraries of the bacterial 16S rRNA gene and 5 libraries of the archaeal 16S rRNA gene was assessed. Diversity measured by several alpha diversity indices (ACE, Chao, Shannon and Simpson) revealed significant differences in diversity indices between lake and river samples. The site with higher microbial diversity was in the Solimões River (4S), downstream the confluence with Purus River. The most common bacterial taxon was the cosmopolitan Polynucleobacter genus, widely observed in all samples. The phylum Thaumarchaeota was the prevailing archaeal taxon. Our results provide the first insight into the microbial diversity of the world's largest river basin.
亚马逊地区拥有地球上最大的水系流域，并且以其丰富多样的动植物生物多样性而闻名。然而，作为该地区主要水道之一的索利蒙伊斯河，目前缺乏关于其水生微生物生物多样性的研究。为了调查该地区的微生物生物多样性，我们对索利蒙伊斯河以及相邻的河流和湖泊进行了16S rRNA基因克隆文库分析。我们的问题是，该流域这一区域的不同类型水生环境中栖息着哪些微生物，以及这些环境（河流和湖泊）之间的多样性如何变化。我们评估了由13个细菌16S rRNA基因克隆文库和5个古菌16S rRNA基因文库所产生的微生物多样性。通过几种α多样性指数（ACE、Chao、Shannon和Simpson）测量的多样性表明，湖泊和河流样本之间的多样性指数存在显著差异。微生物多样性较高的地点位于索利蒙伊斯河（4S），即与普鲁斯河交汇处的下游。最常见的细菌分类群是在所有样本中广泛观察到的世界性多核杆菌属。泉古菌门是主要的古菌分类群。我们的研究结果首次揭示了世界上最大流域的微生物多样性。
