Distribution of Hydrogen-Producing Bacteria in Tibetan Hot Springs, China

Abstract

Investigating the distribution of hydrogen-producing bacteria (HPB) is of great significance to understanding the source of biological hydrogen production in geothermal environments. Here, we explored the compositions of HPB populations in the sediments of hot springs from the Daggyai, Quzhuomu, Quseyongba, and Moluojiang geothermal zones on the Tibetan Plateau, with the use of Illumina MiSeq high-throughput sequencing of 16S rRNA genes and hydA genes. In the present study, the hydA genes were successfully amplified from the hot springs with a temperature of 46–87°C. The hydA gene phylogenetic analysis showed that the top three phyla of the HPB populations were Bacteroidetes (14.48%), Spirochaetes (14.12%), and Thermotogae (10.45%), while Proteobacteria were absent in the top 10 of the HPB populations, although Proteobacteria were dominant in the 16S rRNA gene sequences. Canonical correspondence analysis results indicate that the HPB community structure in the studied Tibetan hot springs was correlated with various environmental factors, such as temperature, pH, and elevation. The HPB community structure also showed a spatial distribution pattern; samples from the same area showed similar community structures. Furthermore, one HPB isolate affiliated with Firmicutes was obtained and demonstrated the capacity of hydrogen production. These results are important for us to understand the distribution and function of HPB in hot springs.

Local and global chemical shaping of bacterial communities by redox potential

“…The locations of study sites are shown in Fig. 3 (Luan et al, 2020), hot springs in the Southern Tibetan Plateau (Ma et al, 2021), water samples from the Three Gorges Reservoir (Gao et al, 2021), and wells in the Mahomet Aquifer, Illinois, USA (Yamamoto et al, 2019). Studies used field-collected samples except for those indicated by square symbols, which are for laboratory experiments or mesocosms.…”

“…Dashed lines represent fits with a slope of less than 0.01 V -1 . Numbers for datasets are (1) Bison Pool, Yellowstone National Park (unlike the other datasets, DNA was extracted from biofilm samples) (Swingley et al, 2012), (2) acidic and (3) circumneutral to alkaline New Zealand hot springs (Power et al, 2018), (4) Dallol Geothermal Area (hypersaline and moderate to extremely acidic water) (Belilla et al, 2019), (5) Copahue Volcano-Río Agrio (Lopez Bedogni et al, 2020;Massello et al, 2020), (6) Southwestern Yunnan (seven samples with pH > 7 and two moderately acidic samples) (Guo et al, 2021), (7) Eastern Tibetan Plateau (Guo et al, 2020), (8) Uzon Caldera (nine samples for acidic water and sediment and one high-pH sample) (Peltek et al, 2020), (9) Southern Tibetan Plateau (Ma et al, 2021), (10) Japan Hydrothermal Sediment (Omae et al, 2019). See Figure S1 for individual sample values.…”

Community- and genome-based evidence for a shaping influence of redox potential on bacterial protein evolution

“…If the location of source material for laboratory or mesocosm studies was not specified, the institutional address was used. Small open circles indicate sampling transects for paddy soils in East Asia ( 76 ), hot springs in the Southern Tibetan Plateau ( 38 ), and water samples from the Three Gorges Reservoir ( 25 ); small filled triangles represent 20 worldwide ports ( 14 ). ( b ) Eh–pH diagram for all environment types.…”

“…Colors are used to represent sample characteristics (acidic water, circumneutral to alkaline water, and sediment). Numbers for data sets are (1) acidic and (2) circumneutral to alkaline New Zealand hot springs ( 15 ), (3) Eastern Tibetan Plateau ( 36 ), (4) Uzon Caldera (including nine samples for acidic water and sediment and one high-pH sample) ( 37 ), and (5) Southern Tibetan Plateau ( 38 ).…”