Acid mine drainage (AMD) microbial communities contain microbial eukaryotes (both fungi and protists) that confer a biofilm structure and impact the abundance of bacteria and archaea and the community composition via grazing and other mechanisms. Since prokaryotes impact iron oxidation rates and thus regulate AMD generation rates, it is important to analyze the fungal and protistan populations. We utilized 18S rRNA and beta-tubulin gene phylogenies and fluorescent rRNA-specific probes to characterize the eukaryotic diversity and distribution in extremely acidic (pHs 0.8 to 1.38), warm (30 to 50°C), metal-rich (up to 269 mM Fe2+, 16.8 mM Zn, 8.5 mM As, and 4.1 mM Cu) AMD solutions from the Richmond Mine at Iron Mountain, Calif. A Rhodophyta (red algae) lineage and organisms from the Vahlkampfiidae family were identified. The fungal 18S rRNA and tubulin gene sequences formed two distinct phylogenetic groups associated with the classes Dothideomycetes and Eurotiomycetes. Three fungal isolates that were closely related to the Dothideomycetes clones were obtained. We suggest the name “Acidomyces richmondensis” for these isolates. Since these ascomycete fungi were morphologically indistinguishable, rRNA-specific oligonucleotide probes were designed to target the Dothideomycetes and Eurotiomycetes via fluorescent in situ hybridization (FISH). FISH analyses indicated that Eurotiomycetes are generally more abundant than Dothideomycetes in all of the seven locations studied within the Richmond Mine system. This is the first study to combine the culture-independent detection of fungi with in situ detection and a demonstration of activity in an acidic environment. The results expand our understanding of the subsurface AMD microbial community structure.
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机译:酸性矿山排水(AMD)微生物群落包含微生物真核生物(真菌和原生生物),它们赋予生物膜结构并通过放牧和其他机制影响细菌和古细菌的丰富度以及群落组成。由于原核生物会影响铁的氧化速率,从而调节AMD的生成速率,因此分析真菌和protanstan种群非常重要。我们利用18S rRNA和β-微管蛋白基因系统发育以及荧光rRNA特异性探针来表征真核生物的多样性和分布,该蛋白在极端酸性(pH值为0.8至1.38),温暖(30至50°C),富含金属(高达269 mM)中来自加利福尼亚州铁山里士满矿山的Fe 2 + sup>,16.8 mM Zn,8.5 mM As和4.1 mM Cu)AMD溶液。有红藻(Rhodophyta)谱系和Vahlkampfiidae科的生物。确定。真菌18S rRNA和微管蛋白基因序列形成与Dothideomycetes和Eurotiomycetes类相关的两个不同的系统发生群。获得了与Dothideomycetes克隆密切相关的三个真菌分离株。我们建议将这些分离株命名为“ Acidomyces richmondensis”。由于这些子囊真菌在形态上是无法区分的,因此将rRNA特异性寡核苷酸探针设计为通过荧光原位杂交(FISH)靶向多菌丝和欧洲丝菌。 FISH分析表明,在里士满矿山系统内研究的所有七个地点中,欧洲真菌菌群通常普遍比十二碳菌纲更为丰富。这是首次将不依赖培养物的真菌检测与原位检测相结合,并证明了在酸性环境中的活性的研究。结果扩大了我们对地下AMD微生物群落结构的了解。
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