Contrasting bacterial and archaeal distributions reflecting different geochemical processes in a sediment core from the Pearl River Estuary
Contrasting bacterial and archaeal distributions reflecting different geochemical processes in a sediment core from the Pearl River Estuary
复制标题
对比细菌和古菌的分布反映了珠江口沉积物核心中不同的地球化学过程
DOI：
10.1186/s13568-020-0950-y
复制
发表时间：
2020
期刊：
影响因子：
3.7
通讯作者：
Zhang Chuanlun
中科院分区：
文献类型：
--
作者：
Wang Wenxiu;Tao Jianchang;Liu Haodong;Li Penghui;Chen Songze;Wang Peng;Zhang Chuanlun
微生物群落结构和代谢活动对海洋沉积物的生态地球化学过程有着重要的影响。功能性细菌如硝酸盐还原菌和硫酸盐还原菌通过耦合特定的反应来响应氧化还原梯度，这些反应适合于相关的能量代谢。然而，类似的功能模式尚未观察到沉积古菌（除了厌氧甲烷氧化菌和产甲烷菌）。以珠江口（PRE）300 cm柱状沉积物为研究对象，结合分类组成和综合地球化学种，研究了不同细菌和古菌在沉积地球化学循环中的参与。地球化学性质（NO3−、溶解Mn和Fe、SO 42+、NH 4 +;溶解无机碳（DIC）、δ 13 CDIC、溶解有机碳（DOC）、总有机碳（TOC）、δ 13 CTOC和荧光溶解有机质（FDOM））表现出不同趋势的强烈深度变化。细菌16 S rRNA和dsrB基因丰度随深度急剧下降，而古菌和深海古菌16 S rRNA基因拷贝相对恒定。这导致古细菌的相对丰度从表面（11.6%）到底部（42.8%）增加。网络分析表明，脱硫菌目、互养菌和γ-变形菌与SO 42-和溶解态Mn呈极显著正相关（P < 0.0001），而深海古菌、C3组和海洋底栖D组（MBGD）与NH 4+、δ 13 CTOC值和类腐殖酸FDOM呈极显著正相关（P < 0.0001）。我们的研究表明，这些细菌群体占主导地位的氧化还原过程中有关的硫酸盐或金属氧化物，而古细菌群体更喜欢在厌氧沉积物中降解难降解的有机化合物。
Microbial community structure and metabolic activities have profound impacts on biogeochemical processes in marine sediments. Functional bacteria such as nitrate- and sulfate-reducing bacteria respond to redox gradients by coupling specific reactions amenable to relevant energy metabolisms. However, similar functional patterns have not been observed for sedimentary archaea (except for anaerobic methanotrophs and methanogens). We coupled taxonomic composition with comprehensive geochemical species to investigate the participation of distinct bacteria and archaea in sedimentary geochemical cycles in a sediment core (300 cm) from Pearl River Estuary (PRE). Geochemical properties (NO3−, dissolved Mn and Fe, SO42+, NH4+; dissolved inorganic carbon (DIC), δ13CDIC, dissolved organic carbon (DOC), total organic carbon (TOC), δ13CTOC, and fluorescent dissolved organic matter (FDOM)) exhibited strong depth variability of different trends. Bacterial 16S rRNA- anddsrBgene abundance decreased sharply with depth while archaeal and bathyarchaeotal 16S rRNA gene copies were relatively constant. This resulted in an increase in relative abundance of archaea from surface (11.6%) to bottom (42.8%). Network analysis showed that bacterial groups ofDesulfobacterales,SyntrophobacteralesandGammaproteobacteriawere significantly (P < 0.0001) associated with SO42−and dissolved Mn while archaeal groups ofBathyarchaeota, Group C3 and Marine Benthic Group D (MBGD) showed close positive correlations (P < 0.0001) with NH4+, δ13CTOCvalues and humic-like FDOM. Our study suggested that these bacterial groups dominated in redox processes relevant to sulfate or metal oxides, while the archaeal groups are more like to degrade recalcitrant organic compounds in anaerobic sediments.