Plant Ecology and Systematics, Biology Institute, University of Kaiserslautern, Kaiserslautern, Germany.
Microbiologyopen. 2019 May;8(5):e00729. doi: 10.1002/mbo3.729. Epub 2018 Sep 21.
Cyanobacteria of biological soil crusts (BSCs) represent an important part of circumpolar and Alpine ecosystems, serve as indicators for ecological condition and climate change, and function as ecosystem engineers by soil stabilization or carbon and nitrogen input. The characterization of cyanobacteria from both polar regions remains extremely important to understand geographic distribution patterns and community compositions. This study is the first of its kind revealing the efficiency of combining denaturing gradient gel electrophoresis (DGGE), light microscopy and culture-based 16S rRNA gene sequencing, applied to polar and Alpine cyanobacteria dominated BSCs. This study aimed to show the living proportion of cyanobacteria as an extension to previously published meta-transcriptome data of the same study sites. Molecular fingerprints showed a distinct clustering of cyanobacterial communities with a close relationship between Arctic and Alpine populations, which differed from those found in Antarctica. Species richness and diversity supported these results, which were also confirmed by microscopic investigations of living cyanobacteria from the BSCs. Isolate-based sequencing corroborated these trends as cold biome clades were assigned, which included a potentially new Arctic clade of Oculatella. Thus, our results contribute to the debate regarding biogeography of cyanobacteria of cold biomes.
生物土壤结皮（BSC）中的蓝细菌是环极和高山生态系统的重要组成部分，作为生态状况和气候变化的指标，并通过土壤稳定或碳氮输入来发挥生态系统工程师的作用。极地蓝细菌的特征描述对于了解地理分布模式和群落组成仍然极为重要。本研究首次结合变性梯度凝胶电泳（DGGE）、光学显微镜和基于培养的 16S rRNA 基因测序，应用于极地和高山蓝细菌为主导的 BSC，揭示了其效率。本研究旨在展示蓝细菌的活比例，作为同一研究地点先前发表的元转录组数据的扩展。分子指纹图谱显示蓝细菌群落聚类明显，与北极和高山种群密切相关，与南极洲的种群不同。物种丰富度和多样性支持了这些结果，BSC 中活蓝细菌的显微镜研究也证实了这一点。基于分离物的测序证实了这些趋势，因为分配了冷生物群的枝系，其中包括一个潜在的新的北极 Oculatella 枝系。因此，我们的研究结果有助于解决冷生物群蓝细菌生物地理学的争论。
