Genderjahn Steffi, Lewin Simon, Horn Fabian, Schleicher Anja M, Mangelsdorf Kai, Wagner Dirk
GFZ German Research Centre for Geosciences, Section Geomicrobiology, Telegrafenberg, 14473 Potsdam, Germany.
GFZ German Research Centre for Geosciences, Section Organic Geochemistry, Telegrafenberg, 14473 Potsdam, Germany.
Microorganisms. 2021 Jan 23;9(2):235. doi: 10.3390/microorganisms9020235.
Dryland xeric conditions exert a deterministic effect on microbial communities, forcing life into refuge niches. Deposited rocks can form a lithic niche for microorganisms in desert regions. Mineral weathering is a key process in soil formation and the importance of microbial-driven mineral weathering for nutrient extraction is increasingly accepted. Advances in geobiology provide insight into the interactions between microorganisms and minerals that play an important role in weathering processes. In this study, we present the examination of the microbial diversity in dryland rocks from the Tsauchab River banks in Namibia. We paired culture-independent 16S rRNA gene amplicon sequencing with culture-dependent (isolation of bacteria) techniques to assess the community structure and diversity patterns. Bacteria isolated from dryland rocks are typical of xeric environments and are described as being involved in rock weathering processes. For the first time, we extracted extra- and intracellular DNA from rocks to enhance our understanding of potentially rock-weathering microorganisms. We compared the microbial community structure in different rock types (limestone, quartz-rich sandstone and quartz-rich shale) with adjacent soils below the rocks. Our results indicate differences in the living lithic and sublithic microbial communities.
旱地干旱条件对微生物群落具有决定性影响，迫使生物进入避难生态位。沉积岩可为沙漠地区的微生物形成一个岩石生态位。矿物风化是土壤形成的关键过程，微生物驱动的矿物风化对养分提取的重要性也越来越被人们所接受。地球生物学的进展为深入了解微生物与矿物之间在风化过程中起重要作用的相互作用提供了依据。在本研究中，我们展示了对纳米比亚察赫布河岸旱地岩石中微生物多样性的研究。我们将非培养的16S rRNA基因扩增子测序与培养依赖（细菌分离）技术相结合，以评估群落结构和多样性模式。从旱地岩石中分离出的细菌是干旱环境中的典型细菌，被认为参与岩石风化过程。我们首次从岩石中提取了细胞外和细胞内DNA，以加深对潜在岩石风化微生物的理解。我们比较了不同岩石类型（石灰岩、富石英砂岩和富石英页岩）与岩石下方相邻土壤中的微生物群落结构。我们的结果表明，岩石内部和岩石下的微生物群落存在差异。
