Microbial community analysis of pH 4 thermal springs in Yellowstone National Park

详细信息    查看全文

• 作者：Xiaoben Jiang ; Cristina D. Takacs-Vesbach
• 关键词：Yellowstone National Park ; Thermal springs ; pH 4 ; Metagenomics ; 16S rRNA ; Microbial communities
• 刊名：Extremophiles
• 出版年：2017
• 出版时间：January 2017
• 年：2017
• 卷：21
• 期：1
• 页码：135-152
• 全文大小：
• 刊物类别：Biomedical and Life Sciences
• 刊物主题：Microbiology; Biotechnology; Biochemistry, general; Microbial Ecology;
• 出版者：Springer Japan
• ISSN：1433-4909
• 卷排序：21

文摘

The pH of the majority of thermal springs in Yellowstone National Park (YNP) is from 1 to 3 and 6 to 10; relatively few springs (~5%) have a pH range of 4–5. We used 16S rRNA gene pyrosequencing to investigate microbial communities sampled from four pH 4 thermal springs collected from four regions of YNP that differed in their fluid temperature and geochemistry. Our results revealed that the composition of bacterial communities varied among the sites, despite sharing similar pH values. The taxonomic composition and metabolic functional potential of the site with the lowest temperature (55 °C), a thermal spring from the Seven Mile Hole (SMH) area, were further investigated using shotgun metagenome sequencing. The taxonomic classification, based on 372 Mbp of unassembled metagenomic reads, indicated that this community included a high proportion of Chloroflexi, Bacteroidetes, Proteobacteria, and Firmicutes. Functional comparison with other YNP thermal spring metagenomes indicated that the SMH metagenome was enriched in genes related to energy production and conversion, transcription, and carbohydrate transport. Analysis of genes involved in nitrogen metabolism revealed assimilatory and dissimilatory nitrate reduction pathways, whereas the majority of genes involved in sulfur metabolism were related to the reduction of sulfate to adenylylsulfate, sulfite, and H₂S. Given that pH 4 thermal springs are relatively less common in YNP and thermal areas worldwide, they may harbor novel microbiota and the communities that inhabit them deserve further investigation.