Cultivation of Exoelectrogenic Bacteria in Conductive DNA Nanocomposite Hydrogels Yields a Programmable Biohybrid Materials System
Cultivation of Exoelectrogenic Bacteria in Conductive DNA Nanocomposite Hydrogels Yields a Programmable Biohybrid Materials System
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DOI：
10.1021/acsami.9b22116
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发表时间：
2020-04-01
影响因子：
9.5
通讯作者：
Niemeyer, Christof M.
中科院分区：
文献类型：
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作者：
Hu, Yong;Rehnlund, David;Niemeyer, Christof M.
在电化学装置中集成活微生物的使用是一个不断扩展的研究领域，其应用于微生物燃料电池、微生物生物传感器或生物反应器。我们描述了使用的多孔纳米复合材料制备的DNA聚合的碳纳米管（CNT）和二氧化硅纳米粒子（SiNPs）的可编程的生物杂交系统的建设含有外生电细菌希瓦氏菌oneidensis。我们初步证明了含CNT的DNA复合材料的电导率，通过计时电位法，电化学阻抗谱，循环伏安法。希瓦氏菌oneidensis在导电材料中的培养表明，外生电细菌填充的导电复合材料的基质，而nonexoelectrogenic大肠杆菌保持在其表面上。此外，使用细胞外电子转移途径的能力与导电合成生物膜基质内的细胞数量正相关。含有希瓦氏菌的复合物在几天内保持稳定，并显示出电化学活性，这表明导电骨架能够提取细菌在严格缺氧条件下产生的代谢电子，并将其传导到阳极。这种生物混合材料系统的可编程性通过按需释放和短期酶刺激诱导的降解来证明。我们相信，这种生物杂化材料的应用可能性甚至可以超越微生物生物传感器，生物反应器和燃料电池系统。
The use of living microorganisms integrated within electrochemical devices is an expanding field of research, with applications in microbial fuel cells, microbial biosensors or bioreactors. We describe the use of porous nanocomposite materials prepared by DNA polymerization of carbon nanotubes (CNTs) and silica nanopartides (SiNPs) for the construction of a programmable biohybrid system containing the exoelectrogenic bacterium Shewanella oneidensis. We initially demonstrate the electrical conductivity of the CNT-containing DNA composite by employment of chronopotentiometry, electrochemical impedance spectroscopy, and cyclic voltammetry. Cultivation of Shewanella oneidensis in the conductive materials shows that the exoelectrogenic bacteria populate the matrix of the conductive composite, while nonexoelectrogenic Escherichia coli remain on its surface. Moreover, the ability to use extracellular electron transfer pathways is positively correlated with the number of cells within the conductive synthetic biofilm matrix. The Shewanella-containing composite remains stable for several days and shows electrochemical activity, indicating that the conductive backbone is capable of extracting the metabolic electrons produced by the bacteria under strictly anoxic conditions and conducting them to the anode. Programmability of this biohybrid material system is demonstrated by on-demand release and degradation induced by a short-term enzymatic stimulus. We believe that the application possibilities of such biohybrid materials could even go beyond microbial biosensors, bioreactors, and fuel cell systems.