Determination of carbon-fixing potential of Bathyarchaeota in marine sediment by DNA stable isotope probing analysis  

作　　者：Wenyue LIANG Tiantian YU Liang DONG Zhongjun JIA Fengping WANG 

机构地区：[1]State Key Laboratory of Microbial Metabolism,School of Life Sciences and Biotechnology,Shanghai Jiao Tong University,Shanghai 200240,China [2]School of Oceanography,Shanghai Jiao Tong University,Shanghai 200240,China [3]State Key Laboratory of Soil and Sustainable Agriculture,Institute of Soil Science,Chinese Academy of Sciences,Nanjing 210008,China

出　　处：《Science China Earth Sciences》2023年第4期910-917,共8页中国科学（地球科学英文版）

基　　金：supported by the State Key R&D Project of China(Grant No.2016YFA0601102);the National Natural Science Foundation of China(Grant Nos.91751205,41525011&41867057)。

摘　　要：Bathyarchaeota is believed to play a crucial role in the global carbon cycle due to its vast biomass,broad distribution,and diverse habitat.However,its physiological and metabolic features are hard to determine without pure culture.While metagenomic analyses have shown that Bathyarchaeota has a complete inorganic carbon fixation(Wood-Ljungdahl,WL)pathway,no direct functional confirmation has been reported.To explore the inorganic carbon fixation ability of Bathyarchaeota,we used lignin and sodium bicarbonate-^(13)C(NaH^(13)CO_(3))in the long-term incubation of marine sediment samples.We found that Bathyarchaeota grew continuously in the cultivation system with lignin,and its abundance increased up to 15.3 times after10 months,increasing its fraction of all archaea from 30%to 80%.We monitored theδ^(13)C of total organic carbon to identify microbial carbon fixation in the cultivation systems,finding that it increased in the first month while NaH^(13)CO_(3)was present but only increased continuously afterward when lignin was also present.Furthermore,ultracentrifugation was performed on DNA extracted from samples at different cultivation stages to separate DNA of different buoyant densities,and bathyarchaeotal and bacterial 16S ribosomal RNA(r RNA)gene abundance were quantified using qPCR.Compared to bacteria,bathyarchaeotal 16S rRNA tended to be concentrated in heavy layers after 4 months of incubation with lignin and NaH^(13)CO_(3),indicating that Bathyarchaeota DNA contained^(13)C through proliferation based on lignin utilization and NaH^(13)CO_(3)assimilation,proving the carbon fixation capacity of Bathyarchaeota.

关 键 词：Bathyarchaeota Reductive acetyl-CoA pathway Carbon fixation DNA-SIP 

分 类 号：Q938.8[生物学—微生物学]