Chen Yu, Dai Tianjiao, Li Niu, Li Qiqi, Lyu Yuanjiao, Di Pengfei, Lyu Lina, Zhang Si, Li Jie
Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China.
CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, Guangdong, China.
Front Microbiol. 2023 Jul 4;14:1199853. doi: 10.3389/fmicb.2023.1199853. eCollection 2023.
Environmental heterogeneity in cold seeps is usually reflected by different faunal aggregates. The sediment microbiome, especially the geochemical cycling-associated communities, sustains the ecosystem through chemosynthesis. To date, few studies have paid attention to the structuring and functioning of geochemical cycling-associated communities relating to environmental heterogeneity in different faunal aggregates of cold seeps. In this study, we profiled the microbial community of four faunal aggregates in the Haima cold seep, South China Sea. Through a combination of geochemical and meta-omics approaches, we have found that geochemical variables, such as sulfate and calcium, exhibited a significant variation between different aggregates, indicating changes in the methane flux. Anaerobic methanotrophic archaea (ANME), sulfate-reducing, and sulfide-oxidizing bacteria (SRB and SOB) dominated the microbial community but varied in composition among the four aggregates. The diversity of archaea and bacteria exhibited a strong correlation between sulfate, calcium, and silicate. Interspecies co-exclusion inferred by molecular ecological network analysis increased from non-seep to clam aggregates and peaked at the mussel aggregate. The networked geochemical cycling-associated species showed an obvious aggregate-specific distribution pattern. Notably, hydrocarbon oxidation and sulfate reduction by ANME and SRB produced carbonate and sulfide, driving the alkalization of the sediment environment, which may impact the microbial communities. Collectively, these results highlighted that geofluid and microbial metabolism together resulted in environmental heterogeneity, which shaped the C and S cycling-associated microbial community.
冷泉中的环境异质性通常由不同的动物群落反映出来。沉积物微生物群落，特别是与地球化学循环相关的群落，通过化学合成维持着生态系统。迄今为止，很少有研究关注与冷泉不同动物群落中环境异质性相关的地球化学循环群落的结构和功能。在本研究中，我们对南海海马冷泉中四个动物群落的微生物群落进行了分析。通过地球化学和宏组学方法的结合，我们发现硫酸盐和钙等地球化学变量在不同群落之间表现出显著差异，表明甲烷通量发生了变化。厌氧甲烷氧化古菌（ANME）、硫酸盐还原菌和硫化物氧化菌（SRB和SOB）在微生物群落中占主导地位，但在四个群落中的组成有所不同。古菌和细菌的多样性与硫酸盐、钙和硅酸盐之间呈现出很强的相关性。通过分子生态网络分析推断，种间共排除从非冷泉群落到蛤群落增加，并在贻贝群落达到峰值。与地球化学循环相关的网络化物种呈现出明显的群落特异性分布模式。值得注意的是，ANME和SRB进行的烃类氧化和硫酸盐还原产生了碳酸盐和硫化物，推动了沉积物环境的碱化，这可能会影响微生物群落。总的来说，这些结果突出表明，地球流体和微生物代谢共同导致了环境异质性，进而塑造了与碳和硫循环相关的微生物群落。
