Filamentous electroactive microorganisms promote mass transfer and sulfate reduction in sediment microbial electrochemical systems
Filamentous electroactive microorganisms promote mass transfer and sulfate reduction in sediment microbial electrochemical systems
复制标题
DOI：
10.1016/j.cej.2023.143214
复制
发表时间：
2023-06
影响因子：
15.1
通讯作者：
Haobin Huang;Yonggang Yang;Shan Yang;Xunan Yang;Youda Huang;Meijun Dong;Shaofeng Zhou;Meiying Xu
中科院分区：
文献类型：
--
作者：
Haobin Huang;Yonggang Yang;Shan Yang;Xunan Yang;Youda Huang;Meijun Dong;Shaofeng Zhou;Meiying Xu
电子传递和质量传递是利用沉积物微生物电化学系统 (SMES) 进行有效沉积物修复的关键过程。越来越多的报告表明，广泛存在于异质沉积物中的丝状电活性微生物（f-EAM）在生物地球化学循环和沉积物修复中发挥着重要作用，显着影响工艺效率。然而，对于f-EAMs在生物地球化学循环和沉积物修复中的作用机制的了解仍然有限。本研究调查了单细胞革兰氏阳性 f-EAM（变异赖氨酸芽孢杆菌 GY32）对 SMES 中硫循环的时空影响。结果表明，添加L.将 variansGY32 注入沉积物中可以显着降低沉积物的扩散阻力高达 49.4%，降低孔隙水硫酸盐浓度高达 46.4%，这验证了 L. variansGY32 有助于增强沉积物中的传质和硫酸盐还原。同时，扩散阻力和孔隙水硫酸盐浓度的垂直差异减小。沉积物电化学和理化性质的动态变化与丝状微生物、硫酸盐还原菌、EAMs（特别是f-EAMs）和互养细菌的富集以及以上述微生物为核心成员的群落相互作用的加强相吻合。我们的研究结果为理解 f-EAM 在生物地球化学循环和沉积物修复中的潜在机制提供了新的见解。
Electron transfer and mass transfer are critical processes for efficient sediment remediation using sediment microbial electrochemical systems (SMESs). Increasing reports show that filamentous electroactive microorganisms (f-EAMs) that widely exist in heterogeneous sediments play essential roles in biogeochemical cycles and sediment remediation, significantly impacting process efficiencies. However, the knowledge of the mechanism of f-EAMs in biogeochemical cycles and sediment remediation is still limited. This study investigated the spatiotemporal effect of a unicellular Gram-positive f-EAM,Lysinibacillus variansGY32, on the sulfur cycle in SMESs. The results showed that addingL. variansGY32 into sediments could significantly decrease the diffusion resistances of the sediments by up to 49.4% and reduce the porewater sulfate concentrations by up to 46.4%, which validated thatL. variansGY32 contributed to enhancing the mass transfer and sulfate reduction in sediments. Meanwhile, the vertical difference in diffusion resistances and porewater sulfate concentrations was reduced. The dynamics of electrochemical and physicochemical properties of sediments coincided well with the enrichment of filamentous microorganisms, sulfate-reducing bacteria, EAMs (especially f-EAMs), and syntrophic bacteria, as well as the reinforcement of the community interactions that took the above microorganisms as core members. Our findings provide novel insights for understanding the underlying mechanism of f-EAMs in biogeochemical cycles and sediment remediation.