Article
Environmental Sciences
Gaojun Wang, Yao Xing, Guohao Liu, Yuxi Chu, Gaofei Yao, Qian Li, Rong Chen
Summary: This study explored the performances and mechanisms of biochar in promoting volatile fatty acids oxidation via extracellular electron transfer pathway. The results showed that adding biochar suspension significantly enhanced electricity generation in a bioelectrochemical system. The lower electrical resistance of the anode in the biochar-assisted groups was potentially attributed to the formation of a biofilm dominated by electro-active Geobacteraceae. Furthermore, the excellent redox-based electron exchange transfer capacity of biochar made it a transient electron acceptor, which supported the metabolism of electroactive bacteria in the initial stage and provided a bridge between suspended sludge and anode to facilitate the evolution of electroactive bacteria on the anode.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Environmental Sciences
Wenjuan Zhao, Guodian Zhao, Yao Jiang, Jing Song, Preetam Sharma, Yeray Asensio Ramirez, Eileen Yu, Shuiliang Chen
Summary: This study investigates the acceleration of denitrification using conductive carrier through the formation of microbial galvanic cell (MGC). It is found that the conductive carrier promotes the enrichment of electroactive denitrifiers and accelerates denitrification rate. The results suggest that denitrification can be accelerated by employing conductive carrier.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2022)
Article
Biochemical Research Methods
Le Yuan, Hongzhong Lu, Feiran Li, Jens Nielsen, Eduard J. Kerkhoven
Summary: In this study, a computational toolbox called HGTphyloDetect was developed, which combines high-throughput analysis with phylogenetic inference to accurately identify horizontal gene transfer (HGT) events and illustrate the transmission pathway among evolutionarily distant or closely related species. The HGTphyloDetect toolbox is user-friendly, capable of detecting HGT events with high efficiency and low false discovery rate.
BRIEFINGS IN BIOINFORMATICS
(2023)
Article
Multidisciplinary Sciences
Meiwei Guo, Chao Wang, Sen Qiao
Summary: In this study, a biohybrid system containing cadmium sulfide nanoparticles (CdS NPs) was constructed, and it was found that photoinduced holes from CdS NPs could be utilized by anammox bacteria to oxidize NH4+ to N-2. This provides a promising and energy-efficient alternative for nitrogen removal from water/wastewater.
Article
Environmental Sciences
Xing Yan, Jie Bu, Xiong Chen, Ming-Jun Zhu
Summary: Microbial extracellular respiration, including Fe(III) and electrode respiration, was observed in Thermoanaerobacterium thermosaccharolyticum MJ2. Comparative genomic analysis revealed the intra/extracellular electron transfer mechanism of MJ2, with hydrogenase and cytochrome c playing crucial roles. Moreover, the addition of exogenous Cyt-c significantly increased the bioelectricity generation by MJ2.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Review
Agricultural Engineering
Xiao Deng, Dan Luo, Akihiro Okamoto
Summary: This review summarizes the mechanisms for enhancing current production in microbial fuel cells and microbial electrosynthesis, and discusses the critical factors for metallic and semiconductive nanoparticles to enhance microbial current generation. It also discusses the implications for microbially induced iron corrosion, photochemically driven microbial electrosynthesis, and several future research directions to further enhance microbial current generation.
BIORESOURCE TECHNOLOGY
(2022)
Article
Environmental Sciences
Lei Chen, Mingpeng Wang, Yujie Feng, Xiaoyu Xu, Xiaobo Luo, Zhaojie Zhang
Summary: Xanthomonas, a common plant pathogen found in biocontaminated bioreactors, was found to exhibit characteristics such as reduction of metal Fe (III) and decolorization of methyl orange in vitro. This microorganism was able to generate bioelectricity and had two extracellular electron transfer pathways, with the indirect transfer method being dominant and faster than direct transfer. The study highlights a novel anaerobic mechanism for Xanthomonas survival during wastewater treatment and suggests potential strategies for preventing its growth.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Biochemistry & Molecular Biology
Arda Gulay, Greg Fournier, Barth F. Smets, Peter R. Girguis
Summary: Many aerobic microbes can use alternative electron acceptors under oxygen-limited conditions, through extracellular electron transfer (EET) to oxidants like iron oxide and manganese oxide. Nitrosomonas communis, an aerobic ammonia-oxidizer, was found to be able to utilize a poised electrode to maintain metabolic activity in anoxic conditions, indicating a potential for EET. The presence of multiheme cytochromes further suggests this capacity. Molecular clock analysis and phylogenetic reconciliations show that the evolution of EET in beta-proteobacterial ammonia oxidizers and the acquisition of multiheme c-type EET proteins likely occurred during the Proterozoic era.
MOLECULAR BIOLOGY AND EVOLUTION
(2023)
Article
Environmental Sciences
Hong-Yu Jin, Zhang-Wei He, Yong-Xiang Ren, Cong-Cong Tang, Ai-Juan Zhou, Wenzong Liu, Qian Sun, Zhihua Li, Aijie Wang
Summary: Conductive materials affect the extra-cellular polymeric substances (EPSs) in anaerobic digestion, leading to an increase or decrease in methane production and changes in the content, composition, and characteristics of EPSs. There is a positive correlation between the maximal methane production potential (Pmax) and the ratio of proteins to polysaccharides (PN/PS) in EPSs, as well as fluorescent substances. EPSs are also related to microbial communities in anaerobic digestion.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Engineering, Environmental
Xiaolin Zhang, Ruixiang Li, Jinning Wang, Chengmei Liao, Lean Zhou, Jingkun An, Tian Li, Xin Wang, Qixing Zhou
Summary: The combined bioremediation of microorganisms and plant roots is an environmentally friendly soil remediation technology. However, the inefficiency of electron transfer is a major obstacle in this process. This study successfully constructed a conductive network of extracellular electron transfer to enhance the microbial conversions and electron transport, leading to improved removal of petroleum hydrocarbons and reduction of iron oxide and nitrogen. The results provide insights into overcoming the inefficient electron transfer during the remediation of organic contaminated soil.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Engineering, Environmental
Yuyi Gu, Xiang Qi, Xufei Yang, Yong Jiang, Panpan Liu, Xiangchun Quan, Peng Liang
Summary: Microbial extracellular electron transfer (EET) is crucial for bioenergy production and wastewater resource recovery. This review summarizes the conductivity of nanowires, biofilms, and granular sludge, and discusses the factors that affect conductivity difference in detail. The high conductivity of nanowires does not necessarily result in efficient EET in microbial aggregates due to non-conductive substances and contact resistance. Improving the conductivity measurement of microbial aggregates is important for calculating EET flux and comparing it with mass transfer coefficients.
Article
Environmental Sciences
Peng Zhang, Bingqian Zhu, Shunling Li, Wei Du, Hongbo Peng, Bo Liu, Zhao Wang
Summary: This study investigated the kinetics and efficiency of biochar in promoting Cr(VI) reduction by S. oneidensis MR-1 in a neutral solution. The results showed that the fast-bioreduction rates were influenced by the conductivity and particle size of biochar, while the slow-bioreduction rates were mainly determined by the electron donating capability of biochar, independent of cell concentration. Manipulating biochar properties may be helpful in effectively removing or detoxifying Cr(VI) in the environment.
Article
Environmental Sciences
Yue Lu, Shoujuan Zhang, Qi Liu, Linrui Zhong, Qingqing Xie, Abing Duan, Zhaohui Yang, Qian Liu, Zhiyi Zhang, Jingru Hao
Summary: The study investigated the effects of the graphite structure on the electron transfer process between bacteria. It found that CNTs exhibited excellent electron shuttle performance, improving the degradation rate of nitrobenzene and shortening the distance of electron transfer.
ENVIRONMENTAL POLLUTION
(2023)
Article
Environmental Sciences
Qian Zhu, Huijie Hou, Yaqian Wu, Jingping Hu, Bingchuan Liu, Sha Liang, Keke Xiao, Wenbo Yu, Shushan Yuan, Jiakuan Yang, Xintai Su
Summary: This study reveals how low concentrations of tetracycline can modulate the extracellular polymeric substances, leading to enhanced extracellular electron transfer efficiency in Geobacter sulfurreducens biofilms.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Microbiology
Sota Ihara, Satoshi Wakai, Tomoko Maehara, Akihiro Okamoto
Summary: This study successfully cultured ultramicrobacteria that passed through a 0.22 μm filter from soil samples and isolated a novel species called Cellulomonas sp. strain NTE-D12. Electrochemical and genomic analyses showed that the strain NTE-D12 had a unique electron transfer system and generated the highest current density.