Article
Microbiology
Jessica A. Smith, Dawn E. Holmes, Trevor L. Woodard, Yang Li, Xinying Liu, Li-Ying Wang, David Meier, Ingrid A. Schwarz, Derek R. Lovley
Summary: Direct interspecies electron transfer (DIET) is an important process in anaerobic communities, but the interactions between DIET partners are not well understood. Geobacter metallireducens expressed type VI secretion system (T6SS) genes when co-cultured with Geobacter sulfurreducens. Disruption of the T6SS gene hcp eliminated the lag periods required for DIET initiation. The hcp-deficient mutant also showed faster reduction of Fe(III) oxide and established DIET quicker with Methanosarcina barkeri. The findings highlight the complex factors influencing DIET effectiveness.
MICROBIOLOGY SPECTRUM
(2023)
Article
Biochemistry & Molecular Biology
Marta A. A. Silva, Ana P. P. Fernandes, David L. L. Turner, Carlos A. A. Salgueiro
Summary: Periplasmic nanowires and electric conductive filaments made of c-type cytochromes from Geobacter sulfurreducens bacterium are crucial for electron storage and/or extracellular electron transfer. The assignment of the heme proton NMR signals for domains C and D in the nanowire cytochrome GSU1996 was obtained and used to guide the assignment of the corresponding signals in the hexaheme bi-domain CD. This new strategy provides a way to functionally characterize large multiheme cytochromes.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
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)
Review
Biotechnology & Applied Microbiology
Toshiyuki Ueki
Summary: Geobacter species are important in environmental biogeochemical cycles and biotechnology applications due to their capability of direct EET with solid electron donors and acceptors. They have a large number of cytochromes encoded in their genomes, localized in various subcellular fractions and utilized differentially for EET with various electron donors and acceptors. Geobacter coordinates the cytochromes with other cellular components in an elaborate EET system to thrive in the environment.
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
(2021)
Article
Engineering, Environmental
Wei Guo, Xianbin Ying, Nannan Zhao, Shengsong Yu, Xu Zhang, Huajun Feng, Yifeng Zhang, Hanqing Yu
Summary: Groundwater nitrate pollution is a severe environmental problem worldwide. Autotrophic denitrification on polarized electrodes, using biofilms consisting of symbiotic growth of Geobacter and denitrifying bacteria, has shown a significantly higher nitrogen removal rate compared to traditional methods. The excellent performance of the biofilms is attributed to the electron transfer ability between Geobacter and denitrifying bacteria, which was verified by suppressing current generation and denitrification through inhibitors. This study reveals a new extracellular electron transfer mechanism and offers insights into the development of efficient biocathodes for treating nitrate pollution in groundwater.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Multidisciplinary Sciences
Wen Yu, Yue Zeng, Zenghao Wang, Shengpeng Xia, Zhiwen Yang, Weijian Chen, Yiming Huang, Fengting Lv, Haotian Bai, Shu Wang
Summary: Developing artificial symbionts with modular design can enhance the production of functional polypeptides using CO2 and N2 as substrates. The strategy improves intracellular ATP and NADPH levels and increases the production of gamma-PGA. This approach also provides an innovative method for creating photosynthetic systems on demand.
Article
Chemistry, Physical
Wenling Zhao, Dong Zhai, Chengcheng Liu, Daoyuan Zheng, Hao Wu, Lei Sun, Zhen Li, Tie Yu, Wei Zhou, Xu Fang, Shengliang Zhai, Keli Han, Zuoli He, Wei-qiao Deng
Summary: The designed ImI-CMP in combination with Co (II) species shows high CO production rate and turnover frequency under visible light irradiation, attributed to the activation effect of imidazolium motifs and the ultrafast intramolecular photoinduced electron transfer facilitated by pi-conjugation structure and built-in electric field.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2022)
Article
Engineering, Environmental
Yue Wu, Baocai Zhang, Yuxuan Wan, Yongheng Jiang, Nan Li, Xinlei Jiang, Chengmei Liao, Xin Wang
Summary: This study demonstrates the feasibility of using iron to reduce nitrate to ammonium and proves the effectiveness of nitrate as an electron acceptor for enriching Geobacter. This finding provides a new route for autotrophic nitrate removal and recycling, with broader implications on nitrogen and iron cycling in biogeochemical processes.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Review
Microbiology
J. A. Gralnick, D. R. Bond
Summary: Extracellular electron transfer is a physiological process in which microbial cells are able to transfer electrons beyond their cell membrane, enabling reduction or oxidation of molecules and minerals. Shewanella and Geobacter were the first bacteria known to possess this capability, utilizing it to couple their growth to the reduction of extracellular iron or manganese minerals. While the transfer of electrons from the inner membrane to the outer surface has been well-studied, recent data suggests a wider range of mechanisms that enable electron transfer to distant acceptors.
ANNUAL REVIEW OF MICROBIOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Gabrielle A. Leith, Allison M. Rice, Brandon J. Yarbrough, Preecha Kittikhunnatham, Abhijai Mathur, Nicholas A. Morris, Megan J. Francis, Anna A. Berseneva, Poonam Dhull, Richard D. Adams, M. Victoria Bobo, Aaron A. Vannucci, Mark D. Smith, Sophya Garashchuk, Natalia B. Shustova
Summary: The research reveals an unprecedented one-step C=C bond cleavage opening the buckybowl, offering access to previously inaccessible carbon-rich structures and demonstrating the potential for drastically different synthetic routes compared to traditional methods for polycyclic aromatic hydrocarbons. Through theoretical modeling and experimental analysis, the study evaluates mechanistic pathways for planarizing the buckybowl, factors influencing this transformation, and the possibility of charge transfer between open buckybowl and electron acceptors. Additionally, a nine-step solution-based approach is presented for preparing novel derivatives with estimated electronic structures and photophysical properties.
Article
Biology
Fengbin Wang, Chi Ho Chan, Victor Suciu, Khawla Mustafa, Madeline Ammend, Dong Si, Allon Hochbaum, Edward H. Egelman, Daniel R. Bond
Summary: Early genetic and structural observations suggested that metal-reducing organisms like Geobacter had extracellular conductive filaments composed of type IV pili. However, recent research has shown that bacterial c-type cytochromes can also form extracellular filaments for long-range electron transport. Cryo-electron microscopy was used to determine the structure of a third extracellular filament, formed from Geobacter sulfurreducens octaheme cytochrome, OmcZ. The structure of OmcZ differs from that of OmcS and OmcE, indicating that conductive cytochrome polymers likely arose independently from different ancestral multiheme proteins.
Article
Engineering, Environmental
Yue Lu, Qingqing Xie, Lin Tang, Jiangfang Yu, Jingjing Wang, Zhaohui Yang, Changzheng Fan, Shoujuan Zhang
Summary: In this study, the addition of Fe-bearing sludge-derived biochar combined with Geobacter sulfurreducens accelerated the reduction of NB, forming biochar with redox-active centers. Through the microbial dissimilatory iron reduction mechanism, the biotic and abiotic reduction rates of NB were effectively improved.
JOURNAL OF HAZARDOUS MATERIALS
(2021)
Article
Environmental Sciences
Yifei Wang, Yaohuan Gao, Abid Hussain, Hyung-Sool Lee
Summary: This study aimed to develop a standardized and consistent method for measuring biofilm conductance to enhance the understanding of extracellular electron transfer. The results showed no significant difference in biofilm conductance with and without a fixed anode potential. The conductance exhibited a sigmoidal relationship with anode potential and deviated from Ohm's law at applied voltages larger than 100 mV. Increasing measurement time led to a decrease in biofilm conductance and further deviation from Ohm's law. By optimizing operation settings, such as voltage range, step, measurement time, and anode control mode, more accurate and consistent biofilm conductance measurement was achieved in the 2-Au MEC system. This study provided a comprehensive evaluation of environmental and instrumental parameters for biofilm conductance measurement.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Microbiology
Zi-Han Liang, Hong Sun, Yang Li, Anyi Hu, Qiang Tang, Han-Qing Yu
Summary: A novel approach is proposed to enhance microbial extracellular electron transfer (EET) by controlling the hydrolyzation of ATP. This approach accelerates carbon substrate consumption, increases biomass accumulation, and expands the intracellular NADH pool, resulting in enhanced EET capability. The method consistently exhibits improved efficiency in the bioconversion of model xenobiotics. This study provides a new perspective and feasible strategy to enhance microbial EET for efficient xenobiotic conversion.
ENVIRONMENTAL MICROBIOLOGY
(2023)
Article
Biochemistry & Molecular Biology
Andreia I. Pimenta, Catarina M. Paquete, Leonor Morgado, Marcus J. Edwards, Thomas A. Clarke, Carlos A. Salgueiro, Ines A. C. Pereira, Americo G. Duarte
Summary: In this study, researchers isolated and characterized the quinone-interacting membrane cytochrome c ImcH from Geobacter sulfurreducens and investigated its role in the extracellular electron transfer (EET) process. The ImcH hemes were found to have low redox potentials and connect the quinol-pool oxidation to EET. The structural model of ImcH shows similarities with the NapC/NirT/NrfH superfamily and it is suggested that ImcH is electroneutral, transferring electrons and protons to the same side of the membrane.
Article
Biochemical Research Methods
Gabriela Canto-Encalada, Diego Tec-Campos, Juan D. Tibocha-Bonilla, Karsten Zengler, Alejandro Zepeda, Cristal Zuniga
Summary: The ammonia-oxidizing bacterium Nitrosomonas europaea plays a significant role in nitrogen cycle and wastewater treatment. Its metabolic versatility and ability to degrade environmental pollutants make it suitable for harsh environmental conditions. The genome-scale metabolic model iGC535 provides quantitative insight into the central and specialized metabolism of N. europaea, particularly in the oxidation of ammonia and pollutant metabolism. The manually curated model can predict phenotypes under different growth conditions and sheds light on the impact of carbon source on key pathways.
PLOS COMPUTATIONAL BIOLOGY
(2022)
Editorial Material
Microbiology
Joanna Coker, Livia S. Zaramela, Karsten Zengler
Summary: Cooperative interaction between low-abundance gut bacteria is essential for converting l-carnitine to TMAO via a multi-step pathway, ultimately leading to an increased risk of cardiovascular disease.
NATURE MICROBIOLOGY
(2022)
Article
Biochemistry & Molecular Biology
Anurag Passi, Juan D. Tibocha-Bonilla, Manish Kumar, Diego Tec-Campos, Karsten Zengler, Cristal Zuniga
Summary: Genome-scale metabolic models (GEMs) enable the quantitative description of the relationship between genotype and phenotype by integrating different types of Big Data. This review analyzes the available Big Data for metabolic modeling and compiles the GEM reconstruction tools that utilize Big Data. It also discusses the applications of GEMs in industry and research, as well as the future prospects in emerging areas.
Article
Microbiology
Livia S. Zaramela, Megan Tjuanta, Oriane Moyne, Maxwell Neal, Karsten Zengler
Summary: The synthetic DNA (synDNA) spike-ins developed in this study enable accurate and reproducible measurements of the absolute amount and fold changes of bacterial species in complex microbial communities. This versatile and promising method can be applied to bacterial communities or genomic features, with the potential for low-cost adaptation by other research groups. The sequences of the synDNAs and plasmids are made available for future application of this method in the study of microbial communities.
Article
Pharmacology & Pharmacy
Yue Zhang, Pier-Luc Tremblay, Tian Zhang
Summary: Coaxial electrospray enables precise control over particle size and size distribution and is used to fabricate PLGA nanoparticles co-encapsulating dapagliflozin and indapamide. The trilayer configuration of the nanoparticles leads to sustained and prolonged release of the drugs compared to monolayer nanoparticles. This study demonstrates the therapeutic advantage of co-encapsulating multiple drugs for the treatment of type 2 diabetes and hypertension.
JOURNAL OF DRUG DELIVERY SCIENCE AND TECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Xiangyang Jiang, Chuchu Tang, Ziyi Zhao, YuXiao Liao, Junhu Zhao, Jiaao Hu, Huan Zhang, Qin Yu, Pier-Luc Tremblay, Tian Zhang
Summary: Waste cotton fabric (WCF) can be recycled as a support for Cr(VI) colorimetric detection. Two strategies, functionalizing cWCF with 1,5-diphenylcarbazide (DPC) or preconcentrating Cr(VI) on cWCF substrate followed by DPC addition, were assessed for Cr(VI) detection in water. Both methods have the advantages of low cost and reusability.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2023)
Article
Chemistry, Analytical
Fan Yang, JinBo Gong, Ming Li, Xiangyang Jiang, Jiawen Zhang, Meiyan Liao, Hanfei Zhang, Pier-Luc Tremblay, Tian Zhang
Summary: The ECL-RET biosensor developed in this study can detect mutations in DNA fragments close to the ends, overcoming the limitations of traditional PCR-based techniques.
ANALYTICAL CHEMISTRY
(2023)
Article
Engineering, Biomedical
Wen Zheng, Wenyue Yang, Wenlong Wei, Ziru Liu, Pier-Luc Tremblay, Tian Zhang
Summary: In this study, an antibacterial, biocompatible, adhesive, anti-inflammatory, and electroconductive hydrogel was developed for injury repair applications. The hydrogel combines multiple functionalities, including the incorporation of silver nanoparticles and the addition of cyclodextrin, to promote tissue repair and accelerate the healing of skin wounds. The results of the study demonstrate that the hydrogel exhibits excellent biocompatibility and antimicrobial activity, and has the potential to enhance wound healing under electrical stimulation.
ADVANCED HEALTHCARE MATERIALS
(2023)
Article
Biochemical Research Methods
Diego Tec-Campos, Camila Posadas, Juan D. Tibocha-Bonilla, Deepan Thiruppathy, Nathan Glonek, Cristal Zuniga, Alejandro Zepeda, Karsten Zengler
Summary: The purple non-sulfur bacterium Rhodopseudomonas palustris is recognized for its important role in nitrogen and carbon cycling and its presence in wastewater treatment communities. It is capable of various metabolic processes under different growth conditions and can degrade a wide range of pollutants. However, many of its metabolic mechanisms remain unknown. In this study, a comprehensive metabolic model was developed and validated, enabling a better understanding of R. palustris' metabolic processes in different environments.
PLOS COMPUTATIONAL BIOLOGY
(2023)
Article
Biochemical Research Methods
Maxwell Neal, Deepan Thiruppathy, Karsten Zengler
Summary: This study developed a genome-scale metabolic model of B. fragilis strain 638R, providing a basis for understanding its relationship with human diet and metabolic products.
PLOS COMPUTATIONAL BIOLOGY
(2023)
Editorial Material
Microbiology
Nils Risgaard-Petersen, Amelia-Elena Rotaru
FRONTIERS IN MICROBIOLOGY
(2023)
Article
Nanoscience & Nanotechnology
Mengying Xu, Pier-Luc Tremblay, Tian Zhang
Summary: A heterojunction metal oxide semiconductor, consisting of three phases of bismuth molybdate (BMO) α, β, γ, was synthesized from a metal-organic framework (MOF) through a one-pot process. This heterostructure showed superior sensing performance for the detection of the toxic gas triethylamine (TEA) compared to BMO prepared with uncoordinated bismuth nitrate. The αβγ-BMO-MOF heterojunction sensor exhibited high performance with a limit of detection of 0.5 ppm and a response value of 58.5 to 100 ppm TEA at an optimal temperature of 340°C. The sensor also demonstrated excellent selectivity, long-term stability, and short response and recovery times. The features of the heterostructure material, including higher electrical resistance and adsorption of oxygen anions, explained its superior TEA sensing performance.
ACS APPLIED NANO MATERIALS
(2023)
Article
Chemistry, Physical
Junhu Zhao, Ming Li, Peng Yang, Xiangyang Jiang, Zhaojin Lv, Pier-Luc Tremblay, Tian Zhang
Summary: This study reports the production of aromatic ketones using a solid acid catalyst modified with p-divinylbenzene-vinylimidazole, 1,3-propanesultone, and trifluoromethanesulfonate. The catalyst showed high conversion and selectivity for anisole to p-methoxyacetophenone using acetic anhydride as the acylating agent. The porous acidic ionic liquid polymer efficiently acylated various aromatic substrates and was reusable.
CATALYSIS SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Physical
Wusheng Rao, Yu Kang, Heng Zheng, Muwei Ye, Ziru Liu, Tian Zhang, Pier-Luc Tremblay
Summary: Illumination of semiconductors can enhance CO2 bioconversion by acetogens and other autotrophic microorganisms. Visible light on its own can change the lifestyle of non-photosynthetic aerobic microbes through photoexcitation stress. However, the direct effect of illumination on the metabolism of acetogens without photocatalytic semiconductors remains unclear.
SUSTAINABLE ENERGY & FUELS
(2023)
Article
Biotechnology & Applied Microbiology
Mon Oo Yee, Lars D. M. Ottosen, Amelia-Elena Rotaru
Summary: Improving methane production through electrical current application to anaerobic digesters has garnered interest, but this study shows that electrochemical stimulation has an overall detrimental effect on a direct interspecies electron transfer (DIET) consortium. The presence of an alternative electron donor inhibits efficient electron retrieval by the methanogen from Geobacter and induces catabolic repression of oxidative metabolism in Geobacter.
MICROBIAL BIOTECHNOLOGY
(2023)