Ozuolmez Derya, Moore Elisha K, Hopmans Ellen C, Sinninghe Damsté Jaap S, Stams Alfons J M, Plugge Caroline M
Laboratory of Microbiology, Wageningen University & Research, 6708 WE Wageningen, The Netherlands.
Department of Marine Microbiology and Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, and Utrecht University, P.O. Box 59, 1790 AB Den Burg, The Netherlands.
Microorganisms. 2020 Apr 22;8(4):606. doi: 10.3390/microorganisms8040606.
The conventional perception that the zone of sulfate reduction and methanogenesis are separated in high- and low-sulfate-containing marine sediments has recently been changed by studies demonstrating their co-occurrence in sediments. The presence of methanogens was linked to the presence of substrates that are not used by sulfate reducers. In the current study, we hypothesized that both groups can co-exist, consuming common substrates (H and/or acetate) in sediments. We enriched butyrate-degrading communities in sediment slurries originating from the sulfate, sulfate-methane transition, and methane zone of Aarhus Bay, Denmark. Sulfate was added at different concentrations (0, 3, 20 mM), and the slurries were incubated at 10 °C and 25 °C. During butyrate conversion, sulfate reduction and methanogenesis occurred simultaneously. The syntrophic butyrate degrader was enriched both in sulfate-amended and in sulfate-free slurries, indicating the occurrence of syntrophic conversions at both conditions. Archaeal community analysis revealed a dominance of . The acetoclastic reached high relative abundance in the absence of sulfate, while presence of acetoclastic was independent of the sulfate concentration, temperature, and the initial zone of the sediment. This study shows that there is no vertical separation of sulfate reducers, syntrophs, and methanogens in the sediment and that they all participate in the conversion of butyrate.
传统观念认为，在高硫酸盐和低硫酸盐含量的海洋沉积物中，硫酸盐还原区和甲烷生成区是分开的，但最近的研究表明它们在沉积物中共存，这一观念已被改变。产甲烷菌的存在与硫酸盐还原菌不利用的底物的存在有关。在本研究中，我们假设这两组微生物可以共存，在沉积物中消耗共同的底物（氢气和/或乙酸盐）。我们从丹麦奥胡斯湾的硫酸盐区、硫酸盐-甲烷过渡区和甲烷区采集沉积物浆液，富集降解丁酸盐的群落。添加不同浓度（0、3、20 mM）的硫酸盐，并将浆液在10℃和25℃下培养。在丁酸盐转化过程中，硫酸盐还原和甲烷生成同时发生。在添加硫酸盐和未添加硫酸盐的浆液中，互营丁酸盐降解菌均得到富集，表明在这两种条件下均发生了互营转化。古菌群落分析显示，[具体古菌名称未给出]占主导地位。在没有硫酸盐的情况下，乙酸裂解[具体古菌名称未给出]达到较高的相对丰度，而乙酸裂解[具体古菌名称未给出]的存在与硫酸盐浓度、温度和沉积物的初始区域无关。这项研究表明，沉积物中硫酸盐还原菌、互营菌和产甲烷菌不存在垂直分离，它们都参与丁酸盐的转化。
