Ma Li, She Weiyu, Wu Geng, Yang Jian, Phurbu Dorji, Jiang Hongchen
State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan 430074, China.
Tibet Plateau Institute of Biology, Lhasa 850000, China.
Microorganisms. 2021 Mar 12;9(3):583. doi: 10.3390/microorganisms9030583.
The distribution and diversity of sulfate/sulfite reduction prokaryotic (SRP) communities in hot springs from the Quzhuomu and Daggyai Geothermal Zone of Tibetan, China, was reported for the first time. In hot springs that are naturally hyperthermal and anoxic, the sulfur cycle is one of the most active cycles of the elements. The distribution of SRP in response to temperature is of great importance to the understanding of biogeochemical cycling of sulfur in geothermal features. Little is known about the SRP in geothermal zone. In this study, the diversity of SRP was investigated in the sediments from the Daggyai and Quzhuomu geothermal zone using PCR amplification, cloning and sequencing of the dissimilatory sulfite reductase beta subunit gene (). The abundance of 16S rRNA genes, were determined by quantitative polymerase chain reactions. In addition, correlations of the SRP assemblages with environmental factors were analyzed by the aggregated boosted tree (ABT) statistical analysis. The results showed that SRP populations were diverse, but were mainly composed of , , , and , and large fraction (25%) of novel sequences have branched groups in the phylogenetic tree. In Quzhuomu geothermal zone, sulfate-rich hot springs are characterized by thick bacterial mats that are green or red and the SRP populations mainly appear at mid-temperature (50 °C to 70 °C). In low-sulfate hot springs in the Daggyai geothermal zone, although gray or pink streamers are widely formed at 60 °C to 80 °C, they prefer to inhabit in green mat at lower temperature (30 °C to 50 °C). With increasing temperature, the diversity of the gene at the OTU level (cutoff 97%) decreased, while its relative abundance increased. This result suggests that temperature played an important role in affecting gene distribution.
首次报道了中国西藏曲卓木和达盖地热区温泉中硫酸盐/亚硫酸盐还原原核生物（SRP）群落的分布和多样性。在天然高温缺氧的温泉中，硫循环是最活跃的元素循环之一。SRP随温度的分布对于理解地热特征中硫的生物地球化学循环至关重要。关于地热区的SRP知之甚少。在本研究中，利用异化亚硫酸盐还原酶β亚基基因（）的PCR扩增、克隆和测序，研究了达盖和曲卓木地热区沉积物中SRP的多样性。通过定量聚合酶链反应测定16S rRNA基因的丰度。此外，通过聚合增强树（ABT）统计分析，分析了SRP组合与环境因素的相关性。结果表明，SRP种群多样，但主要由、、、和组成，并且在系统发育树中，很大一部分（25%）新序列具有分支类群。在曲卓木地热区，富含硫酸盐的温泉以绿色或红色的厚细菌垫为特征，SRP种群主要出现在中温（50℃至70℃）区域。在达盖地热区的低硫酸盐温泉中，尽管在60℃至80℃广泛形成灰色或粉色的丝状菌，但它们更倾向于栖息在较低温度（30℃至50℃）的绿色菌垫中。随着温度升高，OTU水平（截止值97%）的基因多样性降低，而其相对丰度增加。这一结果表明温度在影响基因分布方面发挥了重要作用。
