1
|
Huang S, Méheust R, Barquera B, Light SH. Versatile roles of protein flavinylation in bacterial extracyotosolic electron transfer. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.13.584918. [PMID: 38559090 PMCID: PMC10979944 DOI: 10.1101/2024.03.13.584918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Bacteria perform diverse redox chemistries in the periplasm, cell wall, and extracellular space. Electron transfer for these extracytosolic activities is frequently mediated by proteins with covalently bound flavins, which are attached through post-translational flavinylation by the enzyme ApbE. Despite the significance of protein flavinylation to bacterial physiology, the basis and function of this modification remains unresolved. Here we apply genomic context analyses, computational structural biology, and biochemical studies to address the role of ApbE flavinylation throughout bacterial life. We find that ApbE flavinylation sites exhibit substantial structural heterogeneity. We identify two novel classes of flavinylation substrates that are related to characterized proteins with non-covalently bound flavins, providing evidence that protein flavinylation can evolve from a non-covalent flavoprotein precursor. We further find a group of structurally related flavinylation-associated cytochromes, including those with the domain of unknown function DUF4405, that presumably mediate electron transfer in the cytoplasmic membrane. DUF4405 homologs are widespread in bacteria and related to ferrosome iron storage organelle proteins that may facilitate iron redox cycling within ferrosomes. These studies reveal a complex basis for flavinylated electron transfer and highlight the discovery power of coupling comparative genomic analyses with high-quality structural models.
Collapse
Affiliation(s)
- Shuo Huang
- Duchossois Family Institute, University of Chicago, Chicago, IL, USA
- Department of Microbiology, University of Chicago, Chicago, IL, USA
| | - Raphaël Méheust
- Génomique Métabolique, CEA, Genoscope, Institut François Jacob, Université d’Évry, Université Paris-Saclay, CNRS, Evry, France
| | - Blanca Barquera
- Department of Biological Sciences, Department of Chemistry and Chemical Biology, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute; Troy, NY
| | - Samuel H. Light
- Duchossois Family Institute, University of Chicago, Chicago, IL, USA
- Department of Microbiology, University of Chicago, Chicago, IL, USA
| |
Collapse
|
2
|
Ouyang B, Wei D, Wu B, Yan L, Gang H, Cao Y, Chen P, Zhang T, Wang H. In the View of Electrons Transfer and Energy Conversion: The Antimicrobial Activity and Cytotoxicity of Metal-Based Nanomaterials and Their Applications. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2303153. [PMID: 37721195 DOI: 10.1002/smll.202303153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 08/28/2023] [Indexed: 09/19/2023]
Abstract
The global pandemic and excessive use of antibiotics have raised concerns about environmental health, and efforts are being made to develop alternative bactericidal agents for disinfection. Metal-based nanomaterials and their derivatives have emerged as promising candidates for antibacterial agents due to their broad-spectrum antibacterial activity, environmental friendliness, and excellent biocompatibility. However, the reported antibacterial mechanisms of these materials are complex and lack a comprehensive understanding from a coherent perspective. To address this issue, a new perspective is proposed in this review to demonstrate the toxic mechanisms and antibacterial activities of metal-based nanomaterials in terms of energy conversion and electron transfer. First, the antimicrobial mechanisms of different metal-based nanomaterials are discussed, and advanced research progresses are summarized. Then, the biological intelligence applications of these materials, such as biomedical implants, stimuli-responsive electronic devices, and biological monitoring, are concluded based on trappable electrical signals from electron transfer. Finally, current improvement strategies, future challenges, and possible resolutions are outlined to provide new insights into understanding the antimicrobial behaviors of metal-based materials and offer valuable inspiration and instructional suggestions for building future intelligent environmental health.
Collapse
Affiliation(s)
- Baixue Ouyang
- School of Metallurgy and Environment, Central South University, Changsha, 410083, P. R. China
| | - Dun Wei
- School of Metallurgy and Environment, Central South University, Changsha, 410083, P. R. China
| | - Bichao Wu
- School of Metallurgy and Environment, Central South University, Changsha, 410083, P. R. China
| | - Lvji Yan
- School of Metallurgy and Environment, Central South University, Changsha, 410083, P. R. China
| | - Haiying Gang
- School of Metallurgy and Environment, Central South University, Changsha, 410083, P. R. China
| | - Yiyun Cao
- School of Metallurgy and Environment, Central South University, Changsha, 410083, P. R. China
| | - Peng Chen
- School of Metallurgy and Environment, Central South University, Changsha, 410083, P. R. China
| | - Tingzheng Zhang
- School of Metallurgy and Environment, Central South University, Changsha, 410083, P. R. China
| | - Haiying Wang
- School of Metallurgy and Environment, Central South University, Changsha, 410083, P. R. China
- School of Metallurgy and Environment and Chinese National Engineering Research Center for Control and Treatment of Heavy Metal Pollution, Central South, University, Changsha, 410083, China
| |
Collapse
|
3
|
Li C, Hu S, Ji C, Yi K, Yang W. Insight into the Pseudocapacitive Behavior of Electroactive Biofilms in Response to Dynamic-Controlled Electron Transfer and Metabolism Kinetics for Current Generation in Water Treatment. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:19891-19901. [PMID: 38000046 DOI: 10.1021/acs.est.3c04771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2023]
Abstract
Electroactive biofilms (EBs) engage in complex electron transfer and storage processes involving intracellular and extracellular mediators with temporary electron storage capabilities. Consequently, electroactive biofilms exhibit pseudocapacitive behaviors during substrate degradation processes. However, comprehensive systematic research in this area has been lacking. This study demonstrated that the pseudocapacitive property was an intrinsic characteristic of EBs. This property represents dynamic-controlled electron transfer and is critical in current generation, unlike noncapacitive responses. Nontransient charge and discharge experiments revealed a correlation between capacitive charge accumulation and current generation in EBs. Additionally, analysis of substrate degradation suggested that the maximum power density (Pmax) changed with the kinetic constants of COD degradation, with pseudocapacitances of EBs directly proportional to Pmax. The interaction networks of key latent variables were evaluated through partial least-squares path modeling analysis. The results indicated that cytochrome c was closely associated with the formation of pseudocapacitance in EBs. In conclusion, pseudocapacitance can be considered a valuable indicator for assessing the complex electron transfer behavior of EBs. Pseudocapacitive biofilms have the potential to efficiently regulate biological reactions and serve as a promising carbon-neutral and renewable strategy for energy generation and storage. An in-depth understanding of the intrinsic property of pseudocapacitive behavior in EBs can undoubtedly advance the development of this concept in the future.
Collapse
Affiliation(s)
- Chao Li
- The Key Laboratory of Water and Sediment Sciences, Ministry of Education, College of Environmental Sciences and Engineering, Peking University, No. 5 Yiheyuan Road, Haidian District, Beijing 100871, PR China
| | - Shaogang Hu
- The Key Laboratory of Water and Sediment Sciences, Ministry of Education, College of Environmental Sciences and Engineering, Peking University, No. 5 Yiheyuan Road, Haidian District, Beijing 100871, PR China
| | - Chengcheng Ji
- The Key Laboratory of Water and Sediment Sciences, Ministry of Education, College of Environmental Sciences and Engineering, Peking University, No. 5 Yiheyuan Road, Haidian District, Beijing 100871, PR China
| | - Kexin Yi
- The Key Laboratory of Water and Sediment Sciences, Ministry of Education, College of Environmental Sciences and Engineering, Peking University, No. 5 Yiheyuan Road, Haidian District, Beijing 100871, PR China
| | - Wulin Yang
- The Key Laboratory of Water and Sediment Sciences, Ministry of Education, College of Environmental Sciences and Engineering, Peking University, No. 5 Yiheyuan Road, Haidian District, Beijing 100871, PR China
| |
Collapse
|
4
|
Zhao Q, Lu Y. Anaerobic oxidation of methane in terrestrial wetlands: The rate, identity and metabolism. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 902:166049. [PMID: 37543312 DOI: 10.1016/j.scitotenv.2023.166049] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 07/19/2023] [Accepted: 08/02/2023] [Indexed: 08/07/2023]
Abstract
The recent discovery of anaerobic oxidation of methane (AOM) in freshwater ecosystems has caused a great interest in "cryptic methane cycle" in terrestrial ecosystems. Anaerobic methanotrophs appears widespread in wetland ecosystems, yet, the scope and mechanism of AOM in natural wetlands remain poorly understood. In this paper, we review the recent progress regarding the potential of AOM, the diversity and distribution, and the metabolism of anaerobic methanotrophs in wetland ecosystems. The potential of AOM determined through laboratory incubation or in situ isotopic labeling ranges from 1.4 to 704.0 nmol CH4·g-1 dry soil·d-1. It appears that the availability of electron acceptors is critical in driving different AOM in wetland soils. The environmental temperature and salinity exert a significant influence on AOM activity. Reversal methanogenesis and extracellular electron transfer are likely involved in the AOM process. In addition to anaerobic methanotrophic archaea, the direct involvement of methanogens in AOM is also probable. This review presented an overview of the rate, identity, and metabolisms to unravel the biogeochemical puzzle of AOM in wetland soils.
Collapse
Affiliation(s)
- Qingzhou Zhao
- College of Urban and Environmental Science, Peking University, Beijing 100871, PR China
| | - Yahai Lu
- College of Urban and Environmental Science, Peking University, Beijing 100871, PR China.
| |
Collapse
|
5
|
Abstract
Extracellular electron transfer (EET) is the physiological process that enables the reduction or oxidation of molecules and minerals beyond the surface of a microbial cell. The first bacteria characterized with this capability were Shewanella and Geobacter, both reported to couple their growth to the reduction of iron or manganese oxide minerals located extracellularly. A key difference between EET and nearly every other respiratory activity on Earth is the need to transfer electrons beyond the cell membrane. The past decade has resolved how well-conserved strategies conduct electrons from the inner membrane to the outer surface. However, recent data suggest a much wider and less well understood collection of mechanisms enabling electron transfer to distant acceptors. This review reflects the current state of knowledge from Shewanella and Geobacter, specifically focusing on transfer across the outer membrane and beyond-an activity that enables reduction of highly variable minerals, electrodes, and even other organisms.
Collapse
Affiliation(s)
- J A Gralnick
- BioTechnology Institute and Department of Plant and Microbial Biology, University of Minnesota, St. Paul, Minnesota, USA; ,
| | - D R Bond
- BioTechnology Institute and Department of Plant and Microbial Biology, University of Minnesota, St. Paul, Minnesota, USA; ,
| |
Collapse
|
6
|
Chai F, Li L, Wang W, Xue S, Liu J. Electro-stimulated anaerobic oxidation of methane with synergistic denitrification by adding AQS: Electron transfer mode and mechanism. ENVIRONMENTAL RESEARCH 2023; 229:115997. [PMID: 37105293 DOI: 10.1016/j.envres.2023.115997] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Revised: 04/10/2023] [Accepted: 04/24/2023] [Indexed: 05/21/2023]
Abstract
Denitrifying anaerobic methane-oxidizing (DAMO) processes, which link anaerobic methane oxidation (AMO) and denitrification, have a promising prospect in anaerobic wastewater treatment. In bioelectrochemical systems (BES), DAMO consortium presented potent metabolic activity. However, the extracellular electron transfer (EET) in BES was poorly understood. This study investigated the EET mechanisms and modes of electron transport in BES dominated by anaerobic methanotrophic bacteria. In the bioreactors with the auxiliary voltage of 0.5 and 1.1 V, named EMN-0.5 and EMN-1.1, respectively, biological voltages of 0.198 and 0.329 V were generated with power densities of 0.6 and 1.20 mW/m2, after removing the voltage. High throughput and metagenome analyses demonstrated that main methanotrophs were DAMO bacteria and Methylocystis sp. The electroactive bacteria detected were Pseudomonas sp., Hypomicrobium sp., Thiobacillus sp, and Rhodococcus sp. The pil, cytochrome c, hdr, and he/fp genes related to EET were present on the electrode surfaces. Carbon 13 isotope tracing and chemicals analysis by GC-MS exhibited that methanol was an intermediate product released to extracellular environment and acted as the electronic carrier to drive the EET in methane oxidation. Extracellular electron transfer was achieved through the collaboration of DAMO bacteria, Methylocystis sp., and Pseudomonas sp. Anthraquinone 2-sulfonic acid ester (AQS) could improve the rate of electron transfer to the extracellular space, especially in the EMN-0.5 reaction system. This study provides a new understanding of AMO consortium metabolism in BES and may provide a scientific basis for developing methane control technology.
Collapse
Affiliation(s)
- Fengguang Chai
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, Beijing, 100085, China; School of Ecology and Environment, Zhengzhou University, Zhengzhou, 450001, China
| | - Lin Li
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, Beijing, 100085, China; National Engineering Laboratory for VOCs Pollution Control Material & Technology, University of Chinese Academy of Sciences, Beijing, 101408, China.
| | - Wenwen Wang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, Beijing, 100085, China; University of Chinese Academy of Sciences, 19(A) Yuquan Road, Shijingshan District, Beijing, 100049, China
| | - Song Xue
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing, 100084, PR China
| | - Junxin Liu
- University of Chinese Academy of Sciences, 19(A) Yuquan Road, Shijingshan District, Beijing, 100049, China
| |
Collapse
|
7
|
Chen G, Hu Z, Ebrahimi A, Johnson DR, Wu F, Sun Y, Shen R, Liu L, Wang G. Chemotactic movement and zeta potential dominate Chlamydomonas microsphaera attachment and biocathode development. ENVIRONMENTAL TECHNOLOGY 2023; 44:1838-1849. [PMID: 34859742 DOI: 10.1080/09593330.2021.2014575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 11/29/2021] [Indexed: 06/13/2023]
Abstract
Microalgal cell attaching and biofilm formation are critical in the application of microalgal biocathode, which severs as one of the hopeful candidates to an original cathode in bioelectrochemical systems. Many efforts have been put in biofilm formation and bioelectrochemical systems for years, but the predominant factors shaping microalgal biocathode formation are sketchy. We launched a pair of researches to investigate microalgal attachment and biofilm formation in the presence/absence of applied voltages using Chlamydomonas microsphaera as a model unicellular motile microalga. In this study, we presented how microalga attached and biofilm formed on a carbon felt surface without applied voltages and try to manifest the most important aspects in this process. Results showed that while nutrient sources did not directly regulate cell attachment onto the carbon felt, limited initial nutrient concentration nevertheless promoted cell attachment. Specifically, nutrient availability did not influence the early stage (20-60 min) of microalgal cell attachment but did significantly impact cell attachment during later stages (240-720 min). Further analysis revealed that nutrient availability-mediated chemotactic movements and zeta potential are crucial to facilitate the initial attachment and subsequent biofilm formation of C. microsphaera onto the surfaces, serving as an important factor controlling microalgal surface attachment. Our results demonstrate that nutrient availability is a dominant factor controlling microalgal surface attachment and subsequent biofilm formation processes. This study provides a mechanistic understanding of microalgal surface attachment and biofilm formation processes on carbon felts surfaces in the absence of applied voltages.
Collapse
Affiliation(s)
- Guowei Chen
- Department of Civil Engineering, Hefei University of Technology, Hefei, People's Republic of China
| | - Zhen Hu
- Department of Civil Engineering, Hefei University of Technology, Hefei, People's Republic of China
| | - Ali Ebrahimi
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - David R Johnson
- Department of Environmental Microbiology, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf, Switzerland
| | - Fazhu Wu
- Department of Civil Engineering, Hefei University of Technology, Hefei, People's Republic of China
| | - Yifei Sun
- Department of Soil and Water Sciences, China Agricultural University, Beijing, People's Republic of China
| | - Renhao Shen
- Department of Civil Engineering, Hefei University of Technology, Hefei, People's Republic of China
| | - Li Liu
- Department of Civil Engineering, Hefei University of Technology, Hefei, People's Republic of China
| | - Gang Wang
- Department of Soil and Water Sciences, China Agricultural University, Beijing, People's Republic of China
| |
Collapse
|
8
|
Bjerg JJ, Lustermans JJM, Marshall IPG, Mueller AJ, Brokjær S, Thorup CA, Tataru P, Schmid M, Wagner M, Nielsen LP, Schramm A. Cable bacteria with electric connection to oxygen attract flocks of diverse bacteria. Nat Commun 2023; 14:1614. [PMID: 36959175 PMCID: PMC10036481 DOI: 10.1038/s41467-023-37272-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Accepted: 03/08/2023] [Indexed: 03/25/2023] Open
Abstract
Cable bacteria are centimeter-long filamentous bacteria that conduct electrons via internal wires, thus coupling sulfide oxidation in deeper, anoxic sediment with oxygen reduction in surface sediment. This activity induces geochemical changes in the sediment, and other bacterial groups appear to benefit from the electrical connection to oxygen. Here, we report that diverse bacteria swim in a tight flock around the anoxic part of oxygen-respiring cable bacteria and disperse immediately when the connection to oxygen is disrupted (by cutting the cable bacteria with a laser). Raman microscopy shows that flocking bacteria are more oxidized when closer to the cable bacteria, but physical contact seems to be rare and brief, which suggests potential transfer of electrons via unidentified soluble intermediates. Metagenomic analysis indicates that most of the flocking bacteria appear to be aerobes, including organotrophs, sulfide oxidizers, and possibly iron oxidizers, which might transfer electrons to cable bacteria for respiration. The association and close interaction with such diverse partners might explain how oxygen via cable bacteria can affect microbial communities and processes far into anoxic environments.
Collapse
Affiliation(s)
- Jesper J Bjerg
- Center for Electromicrobiology (CEM), Section for Microbiology, Department of Biology, Aarhus University, Aarhus C, Denmark.
- Microbial Systems Technology Excellence Centre, University of Antwerp, Wilrijk, Belgium.
| | - Jamie J M Lustermans
- Center for Electromicrobiology (CEM), Section for Microbiology, Department of Biology, Aarhus University, Aarhus C, Denmark
| | - Ian P G Marshall
- Center for Electromicrobiology (CEM), Section for Microbiology, Department of Biology, Aarhus University, Aarhus C, Denmark
| | - Anna J Mueller
- Centre for Microbiology and Environmental Systems Science, Division of Microbial Ecology (DOME), University of Vienna, Vienna, Austria
- Doctoral School in Microbiology and Environmental Science, University of Vienna, Vienna, Austria
| | - Signe Brokjær
- Center for Electromicrobiology (CEM), Section for Microbiology, Department of Biology, Aarhus University, Aarhus C, Denmark
| | - Casper A Thorup
- Center for Electromicrobiology (CEM), Section for Microbiology, Department of Biology, Aarhus University, Aarhus C, Denmark
| | - Paula Tataru
- Bioinformatics Research Center (BiRC), Aarhus University, Aarhus C, Denmark
| | - Markus Schmid
- Centre for Microbiology and Environmental Systems Science, Division of Microbial Ecology (DOME), University of Vienna, Vienna, Austria
| | - Michael Wagner
- Centre for Microbiology and Environmental Systems Science, Division of Microbial Ecology (DOME), University of Vienna, Vienna, Austria
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | - Lars Peter Nielsen
- Center for Electromicrobiology (CEM), Section for Microbiology, Department of Biology, Aarhus University, Aarhus C, Denmark
| | - Andreas Schramm
- Center for Electromicrobiology (CEM), Section for Microbiology, Department of Biology, Aarhus University, Aarhus C, Denmark.
| |
Collapse
|
9
|
Römling U. Is biofilm formation intrinsic to the origin of life? Environ Microbiol 2023; 25:26-39. [PMID: 36655713 PMCID: PMC10086821 DOI: 10.1111/1462-2920.16179] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Accepted: 08/19/2022] [Indexed: 01/21/2023]
Abstract
Biofilms are multicellular, often surface-associated, communities of autonomous cells. Their formation is the natural mode of growth of up to 80% of microorganisms living on this planet. Biofilms refractory towards antimicrobial agents and the actions of the immune system due to their tolerance against multiple environmental stresses. But how did biofilm formation arise? Here, I argue that the biofilm lifestyle has its foundation already in the fundamental, surface-triggered chemical reactions and energy preserving mechanisms that enabled the development of life on earth. Subsequently, prototypical biofilm formation has evolved and diversified concomitantly in composition, cell morphology and regulation with the expansion of prokaryotic organisms and their radiation by occupation of diverse ecological niches. This ancient origin of biofilm formation thus mirrors the harnessing environmental conditions that have been the rule rather than the exception in microbial life. The subsequent emergence of the association of microbes, including recent human pathogens, with higher organisms can be considered as the entry into a nutritional and largely stress-protecting heaven. Nevertheless, basic mechanisms of biofilm formation have surprisingly been conserved and refunctionalized to promote sustained survival in new environments.
Collapse
Affiliation(s)
- Ute Römling
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| |
Collapse
|
10
|
Tang Z, Liu R, Chen X, Gao D, Zhang JR, Zhu JJ, Chen Z. Plasmonic Probing Single-Cell Bio-Current Waves with a Shrinking Magnetite Nanoprobe. ACS NANO 2022; 16:20842-20850. [PMID: 36475619 DOI: 10.1021/acsnano.2c08223] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Probing of the single-cell level extracellular electron transfer highlights the maximum output current for microbial fuel cells (MFCs) at hundreds of femtoampere per cell, which is difficult to achieve by existing devices. Past studies focus on the external factors for boosting charge-extraction efficiency from bacteria. Here, we elucidate the intracellular factors that determine this output limit by monitoring the respiratory-driven shrinking kinetics of a single magnetite nanoprobe immobilized on a single Shewanella oneidensis MR-1 cell with plasmonic imaging. Quantified dissolving of nanoprobes unveils a previously undescribed bio-current fluctuation between 0 and 2.7 fA on a ∼40 min cycle. Simultaneously tracing of endogenous oscillations indicates that the bio-current waves are correlated with the periodic cellular electrokinesis. The unsynchronized electron transfer capability in the cell population results in the mean current of 0.24 fA per cell, significantly smaller than in single cells. It explains why the averaged output current of MFCs cannot reach the measured single-cell currents. This work offers a different perspective to improve the power output by extending the active episodes of the bio-current waves.
Collapse
Affiliation(s)
- Zhuodong Tang
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing210023, People's Republic of China
| | - Rui Liu
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing210023, People's Republic of China
| | - Xueqin Chen
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing210023, People's Republic of China
| | - Di Gao
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing210023, People's Republic of China
| | - Jian-Rong Zhang
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing210023, People's Republic of China
| | - Jun-Jie Zhu
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing210023, People's Republic of China
- Shenzhen Research Institute of Nanjing University, Shenzhen518000, People's Republic of China
| | - Zixuan Chen
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing210023, People's Republic of China
| |
Collapse
|
11
|
Jing X, Chen S, Liu X, Yang Y, Rensing C, Zhou S. Potassium channel mediates electroactive biofilm formation via recruiting planktonic Geobacter cells. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 850:158035. [PMID: 35981588 DOI: 10.1016/j.scitotenv.2022.158035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 07/31/2022] [Accepted: 08/11/2022] [Indexed: 06/15/2023]
Abstract
Potassium (K+)-channel-based electrical signaling can coordinate microbial actions at a distance that provides an evolutionary advantage to cell communities. Electroactive cells are usually cultured surrounded by an electric field which provided stronger electrical signaling than the K+-mediated electrical signaling. Whether the K+ signaling also plays a role in coordinating the behavior of electroactive microorganisms has not been accurately demonstrated. Thus, we constructed a K+-channel-deficient strain ΔgsuK of Geobacter sulfurreducens to directly investigate roles of K+ signaling in electroactive biofilm formation for the first time. The ΔgsuK strain exhibited significantly inferior biofilm formation (i.e., biomass, thickness and component) and consequently showed weaker electrical performance (i.e., start-up time, current output, electrochemical catalytic behavior and charge transfer resistance) than the wild-type strain. Individual electric generation capacity and the expression of genes involved in biofilm formation and electrical performance in the single cell did not significantly change with the deletion of gsuK, indicating that K+ signaling indeed influenced the recruiting behavior of planktonic cell but not the functioning of the single cell related to biofilm formation or electric generation. This study is intended to provide an in-depth understanding of electroactive biofilm formation and serve as a basis for optimizing its electrical performance via strengthening the recruitment behavior.
Collapse
Affiliation(s)
- Xianyue Jing
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Shanshan Chen
- Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou 510006, China.
| | - Xing Liu
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Yuting Yang
- Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Christopher Rensing
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Shungui Zhou
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| |
Collapse
|
12
|
Ding DW, Huang WF, Lei LL, Wu P. Co-fitness analysis identifies a diversity of signal proteins involved in the utilization of specific c-type cytochromes. ANN MICROBIOL 2022. [DOI: 10.1186/s13213-022-01694-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Purpose
c-Type cytochromes are essential for extracellular electron transfer (EET) in electroactive microorganisms. The expression of appropriate c-type cytochromes is an important feature of these microorganisms in response to different extracellular electron acceptors. However, how these diverse c-type cytochromes are tightly regulated is still poorly understood.
Methods
In this study, we identified the high co-fitness genes that potentially work with different c-type cytochromes by using genome-wide co-fitness analysis. We also constructed and studied the co-fitness networks that composed of c-type cytochromes and the top 20 high co-fitness genes of them.
Results
We found that high co-fitness genes of c-type cytochromes were enriched in signal transduction processes in Shewanella oneidensis MR-1 cells. We then checked the top 20 co-fitness proteins for each of the 41 c-type cytochromes and identified the corresponding signal proteins for different c-type cytochromes. In particular, through the analysis of the high co-fitness signal protein for CymA, we further confirmed the cooperation between signal proteins and c-type cytochromes and identified a novel signal protein that is putatively involved in the regulation of CymA. In addition, we showed that these signal proteins form two signal transduction modules.
Conclusion
Taken together, these findings provide novel insights into the coordinated utilization of different c-type cytochromes under diverse conditions.
Collapse
|
13
|
Noreen S, Wang E, Feng H, Li Z. Functionalization of TiO 2 for Better Performance as Orthopedic Implants. MATERIALS (BASEL, SWITZERLAND) 2022; 15:6868. [PMID: 36234208 PMCID: PMC9573462 DOI: 10.3390/ma15196868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 09/23/2022] [Accepted: 09/27/2022] [Indexed: 06/16/2023]
Abstract
This review mainly focuses on the surface functionalization approaches of titanium dioxide (TiO2) to prevent bacterial infections and facilitate osteointegration simultaneously for titanium (Ti)-based orthopedic implants. Infection is one of the major causes of implant failure. Meanwhile, it is also critical for the bone-forming cells to integrate with the implant surface. TiO2 is the native oxide layer of Ti which has good biocompatibility as well as enriched physical, chemical, electronic, and photocatalytic properties. The formed nanostructures during fabrication and the enriched properties of TiO2 have enabled various functionalization methods to combat the micro-organisms and enhance the osteogenesis of Ti implants. This review encompasses the various modifications of TiO2 in aspects of topology, drug loading, and element incorporation, as well as the most recently developed electron transfer and electrical tuning approaches. Taken together, these approaches can endow Ti implants with better bactericidal and osteogenic abilities via the functionalization of TiO2.
Collapse
Affiliation(s)
| | | | | | - Zhou Li
- Correspondence: (H.F.); (Z.L.)
| |
Collapse
|
14
|
Cao H, Qiao S, Qin H, Jandt KD. Antibacterial Designs for Implantable Medical Devices: Evolutions and Challenges. J Funct Biomater 2022; 13:jfb13030086. [PMID: 35893454 PMCID: PMC9326756 DOI: 10.3390/jfb13030086] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2022] [Revised: 06/12/2022] [Accepted: 06/17/2022] [Indexed: 11/25/2022] Open
Abstract
The uses of implantable medical devices are safer and more common since sterilization methods and techniques were established a century ago; however, device-associated infections (DAIs) are still frequent and becoming a leading complication as the number of medical device implantations keeps increasing. This urges the world to develop instructive prevention and treatment strategies for DAIs, boosting the studies on the design of antibacterial surfaces. Every year, studies associated with DAIs yield thousands of publications, which here are categorized into four groups, i.e., antibacterial surfaces with long-term efficacy, cell-selective capability, tailored responsiveness, and immune-instructive actions. These innovations are promising in advancing the solution to DAIs; whereas most of these are normally quite preliminary “proof of concept” studies lacking exact clinical scopes. To help identify the flaws of our current antibacterial designs, clinical features of DAIs are highlighted. These include unpredictable onset, site-specific incidence, and possibly involving multiple and resistant pathogenic strains. The key point we delivered is antibacterial designs should meet the specific requirements of the primary functions defined by the “intended use” of an implantable medical device. This review intends to help comprehend the complex relationship between the device, pathogens, and the host, and figure out future directions for improving the quality of antibacterial designs and promoting clinical translations.
Collapse
Affiliation(s)
- Huiliang Cao
- Interfacial Electrochemistry and Biomaterials, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai 200237, China
- Lab of Low-Dimensional Materials Chemistry, Key Laboratory for Ultrafine Materials of Ministry of Education, East China University of Science & Technology, Shanghai 200237, China
- Chair of Materials Science, Otto Schott Institute of Materials Research (OSIM), Friedrich Schiller University Jena, 07743 Jena, Germany
- Correspondence: (H.C.); (S.Q.); (H.Q.); (K.D.J.)
| | - Shichong Qiao
- Department of Implant Dentistry, Shanghai Ninth People’s Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China
- National Clinical Research Center for Oral Diseases, Shanghai 200011, China
- Shanghai Key Laboratory of Stomatology & Shanghai Research Institute of Stomatology, Shanghai 200011, China
- Correspondence: (H.C.); (S.Q.); (H.Q.); (K.D.J.)
| | - Hui Qin
- Department of Orthopaedics, Shanghai Jiaotong University Affiliated Sixth People’s Hospital, Shanghai 200233, China
- Correspondence: (H.C.); (S.Q.); (H.Q.); (K.D.J.)
| | - Klaus D. Jandt
- Chair of Materials Science, Otto Schott Institute of Materials Research (OSIM), Friedrich Schiller University Jena, 07743 Jena, Germany
- Jena Center for Soft Matter (JCSM), Friedrich Schiller University Jena, 07743 Jena, Germany
- Jena School for Microbial Communication (JSMC), Neugasse 23, 07743 Jena, Germany
- Correspondence: (H.C.); (S.Q.); (H.Q.); (K.D.J.)
| |
Collapse
|
15
|
Li Y, Liu K, Mao R, Liu B, Cheng L, Shi X. Unveiling the chemotactic response and mechanism of Shewanella oneidensis MR-1 to nitrobenzene. JOURNAL OF HAZARDOUS MATERIALS 2022; 431:128629. [PMID: 35278967 DOI: 10.1016/j.jhazmat.2022.128629] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 02/25/2022] [Accepted: 03/02/2022] [Indexed: 06/14/2023]
Abstract
Bioreduction by electroactive bacteria (EAB) is considered as a potential and cost-effective approach for the removal of nitroaromatic compounds (NACs). However, little is known about how the widespread EAB sense and respond to slightly soluble NACs in aquatic environments. Here, the chemotactic behaviors of Shewanella oneidensis MR-1, a model EAB, toward several NACs were examined and their underlying molecular mechanism was elucidated. S. oneidensis MR-1 was found to exhibit a strong chemotactic response to nitrobenzene (NB), but not to other selected NACs under aerobic conditions. To sense NB, this bacterium requires both the histidine kinase (CheA-3)-involved chemotactic signal transduction pathway and an inner-membrane c-type cytochrome CymA. Such a chemotactic response is mediated by an energy taxis mechanism. Additionally, external riboflavin was shown to greatly enhance the Shewanella taxis toward NB, implying a feasible way to increase the bioavailability of NACs. The present study deepens our understanding of the role of microbial chemotaxis in the removal of NACs and provides more options for the bioremediation of NAC-contaminated sites.
Collapse
Affiliation(s)
- Yuan Li
- Information Materials and Intelligent Sensing Laboratory of Anhui Province, Anhui Province Key Laboratory of Wetland Ecosystem Protection and Restoration, School of Resources and Environmental Engineering, Anhui University, Hefei 230601, China
| | - Kai Liu
- Information Materials and Intelligent Sensing Laboratory of Anhui Province, Anhui Province Key Laboratory of Wetland Ecosystem Protection and Restoration, School of Resources and Environmental Engineering, Anhui University, Hefei 230601, China
| | - Rongrong Mao
- Information Materials and Intelligent Sensing Laboratory of Anhui Province, Anhui Province Key Laboratory of Wetland Ecosystem Protection and Restoration, School of Resources and Environmental Engineering, Anhui University, Hefei 230601, China
| | - Boya Liu
- Information Materials and Intelligent Sensing Laboratory of Anhui Province, Anhui Province Key Laboratory of Wetland Ecosystem Protection and Restoration, School of Resources and Environmental Engineering, Anhui University, Hefei 230601, China
| | - Lei Cheng
- Information Materials and Intelligent Sensing Laboratory of Anhui Province, Anhui Province Key Laboratory of Wetland Ecosystem Protection and Restoration, School of Resources and Environmental Engineering, Anhui University, Hefei 230601, China.
| | - Xianyang Shi
- Information Materials and Intelligent Sensing Laboratory of Anhui Province, Anhui Province Key Laboratory of Wetland Ecosystem Protection and Restoration, School of Resources and Environmental Engineering, Anhui University, Hefei 230601, China.
| |
Collapse
|
16
|
Deng X, Luo D, Okamoto A. Electrode hydrophilicity enhanced the rate of extracellular electron uptake in Desulfovibrio ferrophilus IS5. Electrochim Acta 2022. [DOI: 10.1016/j.electacta.2022.140504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
17
|
Then A, Ewald J, Söllner N, Cooper RE, Küsel K, Ibrahim B, Schuster S. Agent-based modelling of iron cycling bacteria provides a framework for testing alternative environmental conditions and modes of action. ROYAL SOCIETY OPEN SCIENCE 2022; 9:211553. [PMID: 35620008 PMCID: PMC9115035 DOI: 10.1098/rsos.211553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 04/27/2022] [Indexed: 05/03/2023]
Abstract
Iron-reducing and iron-oxidizing bacteria are of interest in a variety of environmental and industrial applications. Such bacteria often co-occur at oxic-anoxic gradients in aquatic and terrestrial habitats. In this paper, we present the first computational agent-based model of microbial iron cycling, between the anaerobic ferric iron (Fe3+)-reducing bacteria Shewanella spp. and the microaerophilic ferrous iron (Fe2+)-oxidizing bacteria Sideroxydans spp. By including the key processes of reduction/oxidation, movement, adhesion, Fe2+-equilibration and nanoparticle formation, we derive a core model which enables hypothesis testing and prediction for different environmental conditions including temporal cycles of oxic and anoxic conditions. We compared (i) combinations of different Fe3+-reducing/Fe2+-oxidizing modes of action of the bacteria and (ii) system behaviour for different pH values. We predicted that the beneficial effect of a high number of iron-nanoparticles on the total Fe3+ reduction rate of the system is not only due to the faster reduction of these iron-nanoparticles, but also to the nanoparticles' additional capacity to bind Fe2+ on their surfaces. Efficient iron-nanoparticle reduction is confined to pH around 6, being twice as high than at pH 7, whereas at pH 5 negligible reduction takes place. Furthermore, in accordance with experimental evidence our model showed that shorter oxic/anoxic periods exhibit a faster increase of total Fe3+ reduction rate than longer periods.
Collapse
Affiliation(s)
- Andre Then
- Department of Bioinformatics, Matthias-Schleiden-Institute, University of Jena, Ernst-Abbe-Platz 2, 07743 Jena, Germany
| | - Jan Ewald
- Department of Bioinformatics, Matthias-Schleiden-Institute, University of Jena, Ernst-Abbe-Platz 2, 07743 Jena, Germany
| | - Natalie Söllner
- Department of Bioinformatics, Matthias-Schleiden-Institute, University of Jena, Ernst-Abbe-Platz 2, 07743 Jena, Germany
| | - Rebecca E. Cooper
- Institute of Biodiversity, Friedrich Schiller University Jena, Jena, Germany
| | - Kirsten Küsel
- Institute of Biodiversity, Friedrich Schiller University Jena, Jena, Germany
- German Center for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany
| | - Bashar Ibrahim
- Centre for Applied Mathematics and Bioinformatics, and Department of Mathematics and Natural Sciences, Gulf University for Science and Technology, Hawally 32093, Kuwait
- European Virus Bioinformatics Center, Leutragraben 1 07743 Jena, Germany
| | - Stefan Schuster
- Department of Bioinformatics, Matthias-Schleiden-Institute, University of Jena, Ernst-Abbe-Platz 2, 07743 Jena, Germany
| |
Collapse
|
18
|
Tian L, Yan X, Wang D, Du Q, Wan Y, Zhou L, Li T, Liao C, Li N, Wang X. Two key Geobacter species of wastewater-enriched electroactive biofilm respond differently to electric field. WATER RESEARCH 2022; 213:118185. [PMID: 35183018 DOI: 10.1016/j.watres.2022.118185] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 02/10/2022] [Accepted: 02/11/2022] [Indexed: 06/14/2023]
Abstract
Electroactive biofilms have attracted increasing attention due to their unique ability to exchange electrons with electrodes. Geobacter spp. are widely found to be dominant in biofilms in acetate-rich environments when an appropriate voltage is applied, but it is still largely unknown how these bacteria are selectively enriched. Herein, two key Geobacter spp. that have been demonstrated predominant in wastewater-enriched electroactive biofilm after long-term operation, G. sulfurreducens and G. anodireducens, responded to electric field (EF) differently, leading to a higher abundance of EF-sensitive G. anodireducens in the strong EF region after cocultivation with G. sulfurreducens. Transcriptome analysis indicated that two-component systems containing sensor histidine kinases and response regulators were the key for EF sensing in G. anodireducens rather than in G. sulfurreducens, which are closely connected to chemotaxis, c-di-GMP, fatty acid metabolism, pilus, oxidative phosphorylation and transcription, resulting in an increase in extracellular polymeric substance secretion and rapid cell proliferation. Our data reveal the mechanism by which EF select specific Geobacter spp. over time, providing new insights into Geobacter biofilm formation regulated by electricity.
Collapse
Affiliation(s)
- Lili Tian
- MOE Key Laboratory of Pollution Processes and Environmental Criteria / Tianjin Key Laboratory of Environmental Remediation and Pollution Control / College of Environmental Science and Engineering, Nankai University, No. 38 Tongyan Road, Jinnan District, Tianjin 300350, China
| | - Xuejun Yan
- MOE Key Laboratory of Pollution Processes and Environmental Criteria / Tianjin Key Laboratory of Environmental Remediation and Pollution Control / College of Environmental Science and Engineering, Nankai University, No. 38 Tongyan Road, Jinnan District, Tianjin 300350, China
| | - Dongbin Wang
- School of Public Health, Guangdong Medical University, Xincheng Road, Dongguan 523000, China
| | - Qing Du
- School of Environmental and Municipal Engineering, Tianjin Chengjian University, Tianjin 300384, China
| | - Yuxuan Wan
- MOE Key Laboratory of Pollution Processes and Environmental Criteria / Tianjin Key Laboratory of Environmental Remediation and Pollution Control / College of Environmental Science and Engineering, Nankai University, No. 38 Tongyan Road, Jinnan District, Tianjin 300350, China
| | - Lean Zhou
- School of Hydraulic Engineering, Changsha University of Science and Technology, Changsha 410114, China
| | - Tian Li
- MOE Key Laboratory of Pollution Processes and Environmental Criteria / Tianjin Key Laboratory of Environmental Remediation and Pollution Control / College of Environmental Science and Engineering, Nankai University, No. 38 Tongyan Road, Jinnan District, Tianjin 300350, China
| | - Chengmei Liao
- MOE Key Laboratory of Pollution Processes and Environmental Criteria / Tianjin Key Laboratory of Environmental Remediation and Pollution Control / College of Environmental Science and Engineering, Nankai University, No. 38 Tongyan Road, Jinnan District, Tianjin 300350, China
| | - Nan Li
- School of Environmental Science and Engineering, Tianjin University, No. 35 Yaguan Road, Jinnan District, Tianjin 300350, China
| | - Xin Wang
- MOE Key Laboratory of Pollution Processes and Environmental Criteria / Tianjin Key Laboratory of Environmental Remediation and Pollution Control / College of Environmental Science and Engineering, Nankai University, No. 38 Tongyan Road, Jinnan District, Tianjin 300350, China.
| |
Collapse
|
19
|
Tseng CP, Liu F, Zhang X, Huang PC, Campbell I, Li Y, Atkinson JT, Terlier T, Ajo-Franklin CM, Silberg JJ, Verduzco R. Solution-Deposited and Patternable Conductive Polymer Thin-Film Electrodes for Microbial Bioelectronics. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2109442. [PMID: 35088918 DOI: 10.1002/adma.202109442] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2021] [Revised: 01/21/2022] [Indexed: 06/14/2023]
Abstract
Microbial bioelectronic devices integrate naturally occurring or synthetically engineered electroactive microbes with microelectronics. These devices have a broad range of potential applications, but engineering the biotic-abiotic interface for biocompatibility, adhesion, electron transfer, and maximum surface area remains a challenge. Prior approaches to interface modification lack simple processability, the ability to pattern the materials, and/or a significant enhancement in currents. Here, a novel conductive polymer coating that significantly enhances current densities relative to unmodified electrodes in microbial bioelectronics is reported. The coating is based on a blend of poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) crosslinked with poly(2-hydroxyethylacrylate) (PHEA) along with a thin polydopamine (PDA) layer for adhesion to an underlying indium tin oxide (ITO) electrode. When used as an interface layer with the current-producing bacterium Shewanella oneidensis MR-1, this material produces a 178-fold increase in the current density compared to unmodified electrodes, a current gain that is higher than previously reported thin-film 2D coatings and 3D conductive polymer coatings. The chemistry, morphology, and electronic properties of the coatings are characterized and the implementation of these coated electrodes for use in microbial fuel cells, multiplexed bioelectronic devices, and organic electrochemical transistor based microbial sensors are demonstrated. It is envisioned that this simple coating will advance the development of microbial bioelectronic devices.
Collapse
Affiliation(s)
- Chia-Ping Tseng
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, TX, 77005, USA
| | - Fangxin Liu
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, TX, 77005, USA
| | - Xu Zhang
- Department of BioSciences, Rice University, Houston, TX, 77005, USA
| | - Po-Chun Huang
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, TX, 77005, USA
| | - Ian Campbell
- Department of BioSciences, Rice University, Houston, TX, 77005, USA
| | - Yilin Li
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, TX, 77005, USA
| | - Joshua T Atkinson
- Department of Physics and Astronomy, University of Southern California, Los Angeles, CA, 90007, USA
| | - Tanguy Terlier
- SIMS Laboratory, Shared Equipment Authority, Rice University, Houston, TX, 77005, USA
| | | | | | - Rafael Verduzco
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, TX, 77005, USA
- Department of Materials Science and NanoEngineering, Rice University, Houston, TX, 77005, USA
| |
Collapse
|
20
|
Wengang L, Fang C, Rong Z, Cuihong C. Biochar-Mediated Degradation of Roxarsone by Shewanella oneidensis MR-1. Front Microbiol 2022; 13:846228. [PMID: 35369465 PMCID: PMC8964303 DOI: 10.3389/fmicb.2022.846228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Accepted: 02/08/2022] [Indexed: 11/30/2022] Open
Abstract
It is widely believed that biochar plays an essential role in sequestrating pollutants. The impacts of biochar on microbial growth, and consequently on the environmental fate of pollutants, however, remains poorly understood. In this study, wheat-straw-derived biochar was used to investigate how biochar amendment affected Shewanella oneidensis MR-1 growth and roxarsone transformation in water under anaerobic conditions. Three biochar with different physicochemical properties were used to mediate the roxarsone degradation. The results showed that the degradation rate of roxarsone could be accelerated by the increase of biochar pyrolysis temperature. From the characterization of biochar, the total specific surface area, micropore surface area and micropore volume of biochar increase, but the average pore diameter decreases as the pyrolysis temperature increases. Through infrared spectroscopy analysis, it was found that as the pyrolysis temperature increases, the degree of condensation of biochar increases, thereby increasing the pollutant removal rate. From the changes of the relative concentration of MR-1 and its secreted extracellular polymer content, the growth promotion ability of biochar also increases as the pyrolysis temperature increases. These results suggest that wheat-straw-derived biochar may be an important agent for activating microbial growth and can be used to accelerate the transformation of roxarsone, which could be a novel strategy for roxarsone remediation.
Collapse
Affiliation(s)
- Li Wengang
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education)/Tianjin Engineering Center of Environmental Diagnosis and Contamination Remediation, College of Environmental Science and Engineering, Nankai University, Tianjin, China
- School of Resources and Materials, Northeastern University at Qinhuangdao, Qinhuangdao, China
- Tangshan Ecological Environmental Bureau, Tangshan, China
| | - Chen Fang
- School of Resources and Materials, Northeastern University at Qinhuangdao, Qinhuangdao, China
| | - Zhong Rong
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education)/Tianjin Engineering Center of Environmental Diagnosis and Contamination Remediation, College of Environmental Science and Engineering, Nankai University, Tianjin, China
| | - Chen Cuihong
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education)/Tianjin Engineering Center of Environmental Diagnosis and Contamination Remediation, College of Environmental Science and Engineering, Nankai University, Tianjin, China
| |
Collapse
|
21
|
Rehman SU, Niazi RK, Zulqurnain M, Mansoor Q, Iqbal J, Arshad A. Graphene nanoplatelets/CeO2 nanotiles nanocomposites as effective antibacterial material for multiple drug-resistant bacteria. APPLIED NANOSCIENCE 2022; 12:1779-1790. [PMID: 35308867 PMCID: PMC8918601 DOI: 10.1007/s13204-022-02422-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Accepted: 02/12/2022] [Indexed: 01/27/2023]
Abstract
Antibacterial agents with low toxicity to normal cells, redox activity and free radical scavenging property are urgently needed to address the global health crisis. The phenomenal conducting nature of graphene is a best fit to enhance the antibacterial properties of metal oxides. In this work, CeO2 nanotiles and graphene nanoplatelets/CeO2 nanotiles nanocomposites (G/CeO2) have been synthesized by a solvothermal method. The prepared materials have been characterized using XRD, FE-SEM, EDX, and UV–visible spectroscopy techniques to investigate their crystallinity, morphology, composition, and optical bandgap energies. The CeO2 and G/CeO2 nanocomposites have also been tested for antibacterial applications. The neat CeO2 nanotiles sample inhibits the bacterial growth of Pseudomonas aeruginosa and Staphylococcus aureus up to 14.21% and 39.53% respectively. The antibacterial activity was tremendously enhanced using 25% graphene-loaded sample (G/CeO2-II) i.e., approximately 83% loss of P. aeruginosa and 89% in case of S. aureus has been observed. This can be attributed to the unique nano-architecture, oxidative stress due to the excellent ability of reversible conversion between the two electronic states of CeO2 and the stress exerted by the planar graphene and CeO2 nanotiles. Therefore, the G/CeO2 nanocomposites can find potential application as nano-antibiotics for controlling pathogens.
Collapse
Affiliation(s)
- Saliha ur Rehman
- Department of Physics, International Islamic University, Islamabad, Pakistan
| | - Robina Khan Niazi
- Department of Biological Sciences, International Islamic University, Islamabad, Pakistan
| | - M. Zulqurnain
- Department of Physics, The University of Cambridge, 9 JJ Thomson Avenue, Cambridge, CB3 0FA UK
| | - Qaisar Mansoor
- Institute of Biomedical and Genetic Engineering (IBGE), Islamabad, Pakistan
| | - Javed Iqbal
- Laboratory of Nanoscience and Technology (LNT), Department of Physics, Quaid I Azam University, Islamabad, Pakistan
| | - Aqsa Arshad
- Department of Physics, International Islamic University, Islamabad, Pakistan
- Electrical Engineering Division, University of Cambridge, Cambridge, CB3 0FA UK
| |
Collapse
|
22
|
Kuchenbuch A, Frank R, Ramos JV, Jahnke HG, Harnisch F. Electrochemical Microwell Plate to Study Electroactive Microorganisms in Parallel and Real-Time. Front Bioeng Biotechnol 2022; 9:821734. [PMID: 35242754 PMCID: PMC8887713 DOI: 10.3389/fbioe.2021.821734] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 12/28/2021] [Indexed: 11/26/2022] Open
Abstract
Microbial resource mining of electroactive microorganism (EAM) is currently methodically hampered due to unavailable electrochemical screening tools. Here, we introduce an electrochemical microwell plate (ec-MP) composed of a 96 electrochemical deepwell plate and a recently developed 96-channel multipotentiostat. Using the ec-MP we investigated the electrochemical and metabolic properties of the EAM models Shewanella oneidensis and Geobacter sulfurreducens with acetate and lactate as electron donor combined with an individual genetic analysis of each well. Electrochemical cultivation of pure cultures achieved maximum current densities (jmax) and coulombic efficiencies (CE) that were well in line with literature data. The co-cultivation of S. oneidensis and G. sulfurreducens led to an increased current density of jmax of 88.57 ± 14.04 µA cm−2 (lactate) and jmax of 99.36 ± 19.12 µA cm−2 (lactate and acetate). Further, a decreased time period of reaching jmax and biphasic current production was revealed and the microbial electrochemical performance could be linked to the shift in the relative abundance.
Collapse
Affiliation(s)
- Anne Kuchenbuch
- Department of Environmental Microbiology, UFZ—Helmholtz-Centre for Environmental Research GmbH, Leipzig, Germany
| | - Ronny Frank
- Centre for Biotechnology and Biomedicine, Molecular Biological-Biochemical Processing Technology, Leipzig University, Leipzig, Germany
| | - José Vazquez Ramos
- Centre for Biotechnology and Biomedicine, Molecular Biological-Biochemical Processing Technology, Leipzig University, Leipzig, Germany
| | - Heinz-Georg Jahnke
- Centre for Biotechnology and Biomedicine, Molecular Biological-Biochemical Processing Technology, Leipzig University, Leipzig, Germany
| | - Falk Harnisch
- Department of Environmental Microbiology, UFZ—Helmholtz-Centre for Environmental Research GmbH, Leipzig, Germany
- *Correspondence: Falk Harnisch,
| |
Collapse
|
23
|
Chen G, Hu Z, Ebrahimi A, Johnson DR, Wu F, Sun Y, Shen R, Liu L, Wang G. Electrotaxis-mediated cell motility and nutrient availability determine Chlamydomonas microsphaera-surface interactions in bioelectrochemical systems. Bioelectrochemistry 2022; 143:107989. [PMID: 34735914 DOI: 10.1016/j.bioelechem.2021.107989] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 09/28/2021] [Accepted: 10/23/2021] [Indexed: 12/16/2022]
Abstract
Cell attachment onto electrode-forming biocathodes is a promising alternative to expensive catalysts used for electricity production in bioelectrochemical systems (BESs). Though BESs have been extensively studied for decades, the processes, underlying mechanisms, and determinant driving forces of microalgal biocathode formation remain largely unknown. In this study, we employed a model unicellular motile microalga, Chlamydomonas microsphaera, to investigate the microalgal attachment processes onto the electrode surface of a BES and to identify the determinant factors. Results showed that the initial attachment of C. micrrosphaera cells is determined by the applied external voltage rather than nutrient availability and occurs via electrotaxis-mediated cell motility. The subsequent development of the C. microsphaera biofilm is then increasingly determined by nutrient availability. Our results revealed that, in the absence of an external voltage, nutrient availability remains a dominant factor controlling the fate of the microalgal surface attachment and subsequent biofilm formation processes. Thus, our results show that electrotactic and chemotactic movements are crucial to facilitate the initial attachment and subsequent biofilm formation of C. microsphaera onto the electrode surfaces of BES. This study provides new insights into the mechanisms of microalgal surface attachment and biofilm formation processes on microalgal biocathodes, which hold great promise for improving the electrochemical properties of cathodes.
Collapse
Affiliation(s)
- Guowei Chen
- Department of Civil Engineering, Hefei University of Technology, Hefei 230009, China; Anhui Provincial Engineering Laboratory for Rural Water Environment and Resources, Hefei 230009, China; Anhui Province Key Laboratory of Industrial Wastewater and Environmental Treatment, Hefei 230024, China
| | - Zhen Hu
- Department of Civil Engineering, Hefei University of Technology, Hefei 230009, China
| | - Ali Ebrahimi
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - David R Johnson
- Department of Environmental Microbiology, Swiss Federal Institute of Aquatic Science and Technology, Dübendorf 8600, Switzerland
| | - Fazhu Wu
- Department of Civil Engineering, Hefei University of Technology, Hefei 230009, China
| | - Yifeng Sun
- Department of Soil and Water Sciences, China Agricultural University, Beijing 100193, China
| | - Renhao Shen
- Department of Civil Engineering, Hefei University of Technology, Hefei 230009, China
| | - Li Liu
- Department of Civil Engineering, Hefei University of Technology, Hefei 230009, China
| | - Gang Wang
- Department of Soil and Water Sciences, China Agricultural University, Beijing 100193, China.
| |
Collapse
|
24
|
Ultrasonic pre-treatment of Bacillus velezensis for improved electrogenic response in a single chambered microbial fuel cell. 3 Biotech 2022; 12:18. [PMID: 34926122 PMCID: PMC8674389 DOI: 10.1007/s13205-021-03065-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Accepted: 11/12/2021] [Indexed: 01/03/2023] Open
Abstract
Various microbial strains and techniques are being used to improve power production in microbial fuel cells. Cow dung is a peculiar source of anaerobic and micro-aerophilic organisms that were employed in this study to isolate exo-electrogenic microorganisms. To validate their exo-electrogenic nature, all eight visually distinct bacterial single-cell colonies were tested using the ferrocyanide reduction assay, which resulted in the selection of one bacterial strain AD1-ELB with the ability to reduce ferrocyanide for further biochemical, physiological and electrochemical characterization. The selected strain AD1-ELB was identified as Bacillus velezensis by 16 s rRNA gene sequencing. When used in a single-chambered MFC, the isolated AD1-ELB strain produced a maximum open-circuit voltage of 455 mV with a maximum current density of 51.78 µA/cm2 and maximum power density of 4.33 µW/cm2 on the 16th day. Bacillus velezensis AD1-ELB strain was treated with low-frequency ultrasound (40 kHz) for 1, 2, 3, 4, and 5 min to assess the effect of ultrasonic pre-treatment on an isolated pure culture-based microbial fuel cell. A 3-min exposure to low-frequency ultrasonic therapy resulted in an increase in maximum power of 4.33 µW/cm2 with a current density of 51.78 µA/cm2 in the MFC, which decreases significantly after 4 and 5 min. Thus, the overall power density achieved was 1.89 times greater than in MFCs with untreated strain. These findings support the use of low-frequency ultrasonic stimulation to improve the performance of microbial fuel cell devices and are restricted to the pure, single-cell strain AD1-ELB, with the potential for variation if some other isolated strain is utilized, hence requiring further study to determine its relative variations.
Collapse
|
25
|
Xu J, Li C, Shen Y, Zhu N. Anaerobic ammonium oxidation (anammox) promoted by pyrogenic biochar: Deciphering the interaction with extracellular polymeric substances (EPS). THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 802:149884. [PMID: 34464802 DOI: 10.1016/j.scitotenv.2021.149884] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 08/09/2021] [Accepted: 08/20/2021] [Indexed: 06/13/2023]
Abstract
Efficient biological nitrogen removal (BNR) by anaerobic ammonium oxidation (anammox) can be achieved with presence of redox-active pyrogenic biochar that potentially acting as an insoluble electron acceptor. Anammox bacteria and other symbiotic consortia are surrounded by extracellular polymeric substances (EPS) forming aggregate architecture, which also contains electrochemical-active biomolecules such as aromatic proteins and humic substances. Therefore, understanding the role of EPS is necessary in biochar-promoting anammox process. Herein, we investigated the influence of biochar with granular-sized (GP) and micrometer-sized (MP) particle sizes on microbiology and characteristics of EPS in anammox sludge. Addition of GP and MP biochar not only improved the BNR efficiency by 17.5% and 34.6%, respectively, but also increased the relative abundance of Candidatus Brocadia. The bulk and bound EPS contents substantially decreased in biochar-amended groups, while more slime EPS was produced. Spectroscopic (FTIR, Raman, and circular dichroism) and electrochemical (voltammetry and impedance spectrum) analyses revealed that biochar addition enhanced the structural integrity and electron-transfer capability of anammox sludge. EPS depletion led to a steep decrease in BNR efficiency (21.5% vs 83.0% with EPS-retained sludge), whereas it resumed to 42.1% in the presence of MP biochar. Electron transport system activity data showed that biochar replenished the loss of anaerobic respiration metabolism due to EPS depletion. In summary, these results suggested that EPS possibly work as transient mediator for shuttling electrons from ammonium oxidation to soluble (nitrite) and insoluble electron acceptors (redox-active biochar).
Collapse
Affiliation(s)
- Jiajia Xu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China; Shanghai Engineering Research Center of Solid Waste Treatment and Resource Recovery, Shanghai 200240, China
| | - Chao Li
- Hunan BISEN Environmental & Energy Co. Ltd, Changsha 410100, China
| | - Yanwen Shen
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China; Hunan BISEN Environmental & Energy Co. Ltd, Changsha 410100, China; Shanghai Engineering Research Center of Solid Waste Treatment and Resource Recovery, Shanghai 200240, China.
| | - Nanwen Zhu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China; Shanghai Engineering Research Center of Solid Waste Treatment and Resource Recovery, Shanghai 200240, China
| |
Collapse
|
26
|
Hu Y, Wang Y, Han X, Shan Y, Li F, Shi L. Biofilm Biology and Engineering of Geobacter and Shewanella spp. for Energy Applications. Front Bioeng Biotechnol 2021; 9:786416. [PMID: 34926431 PMCID: PMC8683041 DOI: 10.3389/fbioe.2021.786416] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 11/18/2021] [Indexed: 01/04/2023] Open
Abstract
Geobacter and Shewanella spp. were discovered in late 1980s as dissimilatory metal-reducing microorganisms that can transfer electrons from cytoplasmic respiratory oxidation reactions to external metal-containing minerals. In addition to mineral-based electron acceptors, Geobacter and Shewanella spp. also can transfer electrons to electrodes. The microorganisms that have abilities to transfer electrons to electrodes are known as exoelectrogens. Because of their remarkable abilities of electron transfer, Geobacter and Shewanella spp. have been the two most well studied groups of exoelectrogens. They are widely used in bioelectrochemical systems (BESs) for various biotechnological applications, such as bioelectricity generation via microbial fuel cells. These applications mostly associate with Geobacter and Shewanella biofilms grown on the surfaces of electrodes. Geobacter and Shewanella biofilms are electrically conductive, which is conferred by matrix-associated electroactive components such as c-type cytochromes and electrically conductive nanowires. The thickness and electroactivity of Geobacter and Shewanella biofilms have a significant impact on electron transfer efficiency in BESs. In this review, we first briefly discuss the roles of planktonic and biofilm-forming Geobacter and Shewanella cells in BESs, and then review biofilm biology with the focus on biofilm development, biofilm matrix, heterogeneity in biofilm and signaling regulatory systems mediating formation of Geobacter and Shewanella biofilms. Finally, we discuss strategies of Geobacter and Shewanella biofilm engineering for improving electron transfer efficiency to obtain enhanced BES performance.
Collapse
Affiliation(s)
- Yidan Hu
- Department of Biological Sciences and Technology, School of Environmental Studies, China University of Geosciences, Wuhan, China
| | - Yinghui Wang
- Department of Biological Sciences and Technology, School of Environmental Studies, China University of Geosciences, Wuhan, China
| | - Xi Han
- Department of Biological Sciences and Technology, School of Environmental Studies, China University of Geosciences, Wuhan, China
| | - Yawei Shan
- Department of Biological Sciences and Technology, School of Environmental Studies, China University of Geosciences, Wuhan, China
| | - Feng Li
- Key Laboratory of Systems Bioengineering (Ministry of Education), SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering, School of Chemical Engineering and Technology, Tianjin University, Tianjin, China
| | - Liang Shi
- Department of Biological Sciences and Technology, School of Environmental Studies, China University of Geosciences, Wuhan, China.,State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, China.,Hubei Key Laboratory of Yangtze Catchment Environmental Aquatic Science, China University of Geosciences, Wuhan, China.,State Environmental Protection Key Laboratory of Source Apportionment and Control of Aquatic Pollution, Ministry of Ecology and Environment, Wuhan, China
| |
Collapse
|
27
|
Chong P, Erable B, Bergel A. How bacteria use electric fields to reach surfaces. Biofilm 2021; 3:100048. [PMID: 33997766 PMCID: PMC8090995 DOI: 10.1016/j.bioflm.2021.100048] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 03/15/2021] [Accepted: 03/28/2021] [Indexed: 11/15/2022] Open
Abstract
Electrotaxis is the property of cells to sense electric fields and use them to orient their displacement. This property has been widely investigated with eukaryotic cells but it remains unclear whether or not bacterial cells can sense an electric field. Here, a specific experimental set-up was designed to form microbial electroactive biofilms while differentiating the effect of the electric field from that of the polarised electrode surface. Application of an electric field during exposure of the electrodes to the inoculum was shown to be required for an electroactive biofilm to form afterwards. Similar biofilms were formed in both directions of the electric field. This result is attributed to the capacity of the cells to detect the K+ and Na+ ion gradients that the electric field creates at the electrode surface. This microbial property should now be considered as a key factor in the formation of electroactive biofilms and possible implications in the biomedical domain are discussed.
Collapse
Affiliation(s)
- Poehere Chong
- Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INP, UPS, Toulouse, France
| | - Benjamin Erable
- Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INP, UPS, Toulouse, France
| | - Alain Bergel
- Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INP, UPS, Toulouse, France
| |
Collapse
|
28
|
Lherbette M, Regeard C, Marlière C, Raspaud E. Biocorrosion on Nanofilms Induces Rapid Bacterial Motions via Iron Dissolution. ACS CENTRAL SCIENCE 2021; 7:1949-1956. [PMID: 34841065 PMCID: PMC8614109 DOI: 10.1021/acscentsci.1c01126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Indexed: 06/13/2023]
Abstract
Stability and reactivity of solid metal or mineral surfaces in contact with bacteria are critical properties for development of biocorrosion protection and for understanding bacteria-solid environmental interactions. Here, we opted to work with nanosheets of iron nanolayers offering arbitrarily large and stable areas of contact that can be simply monitored by optical means. We focused our study on the sediments' bacteria, the strain Shewanella oneidensis WT MR-1, that served as models for previous research on electroactivity and iron-reduction effects. Data show that a sudden uniform corrosion appeared after an early electroactive period without specific affinities and that iron dissolution induced rapid bacterial motions. By extending the approach to mutant strains and three bacterial species, we established a correlation between corrosion onset and oxygen-depletion combined with iron reduction and demonstrated bacteria's extraordinary ability to transform their solid environments.
Collapse
Affiliation(s)
- Marion Lherbette
- Université
Paris-Saclay, CNRS, Laboratoire de Physique des Solides, 91405 Orsay, France
| | - Christophe Regeard
- Institute
for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, CEA, CNRS, 91198 Gif-sur-Yvette, France
| | - Christian Marlière
- Université
Paris-Saclay, CNRS, Laboratoire de Physique des Solides, 91405 Orsay, France
| | - Eric Raspaud
- Université
Paris-Saclay, CNRS, Laboratoire de Physique des Solides, 91405 Orsay, France
| |
Collapse
|
29
|
Li L, Zhang X, Zhu P, Yong X, Wang Y, An W, Jia H, Zhou J. Enhancing biomethane production and pyrene biodegradation by addition of bio-nano FeS or magnetic carbon during sludge anaerobic digestion. ENVIRONMENTAL TECHNOLOGY 2021; 42:3496-3507. [PMID: 32085684 DOI: 10.1080/09593330.2020.1733674] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Accepted: 02/14/2020] [Indexed: 05/22/2023]
Abstract
Pyrene exerts toxic effects on methanogens during anaerobic digestion of sludge, thus affecting the efficiency of sludge treatment. This study evaluated the facilitated direct interspecific electron transfer (DIET) between bacteria and methanogens when bio-nano FeS or magnetic carbon is added into anaerobic reactors. Results showed that adding 200 mg/L bio-nano FeS or magnetic carbon clearly reduced the accumulation of short-chain fatty acids and avoided acidification during 25 days of anaerobic digestion. The methane productions were 98.38 L/kg total solid (TS) and 73.69 L/kg TS in the bio-nano FeS and magnetic carbon systems, respectively, which accelerated methane production by 58.1% and 33.4%, respectively, compared with the control system (40.26 L/kg TS). The pyrene removal rates reached 77.5% and 72.1% in the bio-nano FeS and magnetic carbon systems, whereas it was only 40.8% in the control system. Analysis of microbial community structure revealed that methanogens (e.g. Methanosarcina and Methanosaeta) and extracellular electron-transfer bacteria (e.g. Pseudomonas, Cloastridia, and Synergistetes) were enriched in the reactors added with bio-nano FeS or magnetic carbon. This result indicates that the addition of bio-nano FeS or magnetic carbon may promote the activity and growth of microorganisms to improve the efficiency of methane production and pyrene degradation by enhancing DIET.
Collapse
Affiliation(s)
- Lian Li
- Bioenergy Research Institute, College of Biotechnology and Pharmaceutical Engineering, Nanjing TECH University, Nanjing, People's Republic of China
- College of Environment, Nanjing TECH University, Nanjing, People's Republic of China
| | - Xueying Zhang
- College of Environment, Nanjing TECH University, Nanjing, People's Republic of China
| | - Peiru Zhu
- Bioenergy Research Institute, College of Biotechnology and Pharmaceutical Engineering, Nanjing TECH University, Nanjing, People's Republic of China
- College of Environment, Nanjing TECH University, Nanjing, People's Republic of China
| | - Xiaoyu Yong
- Bioenergy Research Institute, College of Biotechnology and Pharmaceutical Engineering, Nanjing TECH University, Nanjing, People's Republic of China
| | - Yajun Wang
- National Wolfberry Engineering Research Center, Ningxia Academy of Agriculture and Forestry Sciences, Yinchuan, People's Republic of China
| | - Wei An
- National Wolfberry Engineering Research Center, Ningxia Academy of Agriculture and Forestry Sciences, Yinchuan, People's Republic of China
| | - Honghua Jia
- Bioenergy Research Institute, College of Biotechnology and Pharmaceutical Engineering, Nanjing TECH University, Nanjing, People's Republic of China
| | - Jun Zhou
- Bioenergy Research Institute, College of Biotechnology and Pharmaceutical Engineering, Nanjing TECH University, Nanjing, People's Republic of China
| |
Collapse
|
30
|
Prados MB, Lescano M, Porzionato N, Curutchet G. Wiring Up Along Electrodes for Biofilm Formation. Front Microbiol 2021; 12:726251. [PMID: 34526980 PMCID: PMC8435748 DOI: 10.3389/fmicb.2021.726251] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Accepted: 08/09/2021] [Indexed: 11/13/2022] Open
Abstract
Millimeter-length cables of bacteria were discovered growing along a graphite-rod electrode serving as an anode of a microbial electrolysis cell (MEC). The MEC had been inoculated with a culture of Fe-reducing microorganisms enriched from a polluted river sediment (Reconquista river, Argentina) and was operated at laboratory controlled conditions for 18 days at an anode poised potential of 240 mV (vs. Ag/AgCl), followed by 23 days at 480 mV (vs. Ag/AgCl). Anode samples were collected for scanning electron microscopy, phylogenetic and electrochemical analyses. The cables were composed of a succession of bacteria covered by a membranous sheath and were distinct from the known "cable-bacteria" (family Desulfobulbaceae). Apparently, the formation of the cables began with the interaction of the cells via nanotubes mostly located at the cell poles. The cables seemed to be further widened by the fusion between them. 16S rRNA gene sequence analysis confirmed the presence of a microbial community composed of six genera, including Shewanella, a well-characterized electrogenic bacteria. The formation of the cables might be a way of colonizing a polarized surface, as determined by the observation of electrodes extracted at different times of MEC operation. Since the cables of bacteria were distinct from any previously described, the results suggest that bacteria capable of forming cables are more diverse in nature than already thought. This diversity might render different electrical properties that could be exploited for various applications.
Collapse
Affiliation(s)
- María Belén Prados
- Instituto de Energía y Desarrollo Sustentable, Centro Atómico Bariloche, Comisión Nacional de Energía Atómica, Buenos Aires, Argentina
| | - Mariela Lescano
- Instituto de Energía y Desarrollo Sustentable, Centro Atómico Bariloche, Comisión Nacional de Energía Atómica, Buenos Aires, Argentina
| | - Natalia Porzionato
- Instituto de Investigaciones e Ingeniería Ambiental y Escuela de Ciencia y Tecnología, Universidad Nacional de San Martín, Buenos Aires, Argentina
| | - Gustavo Curutchet
- Instituto de Investigaciones e Ingeniería Ambiental y Escuela de Ciencia y Tecnología, Universidad Nacional de San Martín, Buenos Aires, Argentina
| |
Collapse
|
31
|
Nath D, Das S, Ghangrekar MM. High throughput techniques for the rapid identification of electroactive microorganisms. CHEMOSPHERE 2021; 285:131489. [PMID: 34265713 DOI: 10.1016/j.chemosphere.2021.131489] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 06/20/2021] [Accepted: 07/06/2021] [Indexed: 02/08/2023]
Abstract
Electroactive microorganisms (EAM), capable of executing extracellular electron transfer (EET) in/out of a cell, are employed in microbial electrochemical technologies (MET) and bioelectronics for harnessing electricity from wastewater, bioremediation and as biosensors. Thus, investigation on EAM is becoming a topic of interest for multidisciplinary areas, such as environmental science, energy and health sectors. Though, EAM are widespread in three domains of life, nevertheless, only a few hundred EAM have been identified so far and hence, the rapid identification of EAM is imperative. In this review, the techniques that are developed for the direct identification of EAM, such as azo dye and WO3 based techniques, dielectrophoresis, potentiostatic/galvanometric techniques, and other indirect methods, such as spectroscopy and molecular biology techniques, are highlighted with a special focus on time required for the detection of these EAM. The bottlenecks for identifying EAM and the knowledge gaps based on the present investigations are also discussed. Thus, this review is intended to encourage researchers for devolving high-throughput techniques for identifying EAM with more accuracy, while consuming less time.
Collapse
Affiliation(s)
- Dibyojyoty Nath
- School of Environmental Science & Engineering, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India
| | - Sovik Das
- Department of Civil Engineering, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India
| | - M M Ghangrekar
- School of Environmental Science & Engineering, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India; Department of Civil Engineering, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India.
| |
Collapse
|
32
|
Chen G, Zhu N, Hu Z, Liu L, Wang GQ, Wang G. Motility changes rather than EPS production shape aggregation of Chlamydomonas microsphaera in aquatic environment. ENVIRONMENTAL TECHNOLOGY 2021; 42:2916-2924. [PMID: 31951776 DOI: 10.1080/09593330.2020.1718216] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 01/11/2020] [Indexed: 06/10/2023]
Abstract
Microalgal aggregation is a key for both microalgae harvesting and water purification, where changes in extracellular polymeric substance (EPS) secretion and cell motility changes are of core importance. In this study, we investigated the aggregation process of Chlamydomonas microsphaera confronting resource limitation and chlorine disinfection, and tried to compare changes in the magnitude of EPS secretion and cell motility. Results show that the presence of mild chlorine solution (0.20%) dose stimulated microalgal aggregation (with an aggregated to planktonic cells ratio of 3.2), with extracellular protein concentration and mean cell velocity reaching a maximum of 43.43 ± 0.01 mg/L and 201 ± 35 µm/s, respectively. These values are 71% and 191% higher than those of the control. Comparably, nutrient availability had only a limited impact on microalgal aggregation and was associated with mild EPS secretion and cell motility. Correlation analysis revealed a strong positive impact of cell motility (mean velocity) on microalgae aggregation, with little effect on EPS excretion. Together, these quantitative estimations may shed light on understanding the mechanisms of microalgae aggregation in aqueous systems, which could help future design and practical operation of source water pretreatment or microalgae harvesting.
Collapse
Affiliation(s)
- Guowei Chen
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing, People's Republic of China
- Department of Civil Engineering, Hefei University of Technology, Hefei, People's Republic of China
| | - Ning Zhu
- Department of Civil Engineering, Hefei University of Technology, Hefei, People's Republic of China
| | - Zhen Hu
- Department of Civil Engineering, Hefei University of Technology, Hefei, People's Republic of China
| | - Li Liu
- Department of Civil Engineering, Hefei University of Technology, Hefei, People's Republic of China
| | - Guo-Qing Wang
- Nanjing Hydraulic Research Institute, Nanjing, People's Republic of China
| | - Gang Wang
- Department of Soil and Water Sciences, China Agricultural University, Beijing, People's Republic of China
| |
Collapse
|
33
|
Kees ED, Levar CE, Miller SP, Bond DR, Gralnick JA, Dean AM. Survival of the first rather than the fittest in a Shewanella electrode biofilm. Commun Biol 2021; 4:536. [PMID: 33958697 PMCID: PMC8102560 DOI: 10.1038/s42003-021-02040-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 03/22/2021] [Indexed: 11/09/2022] Open
Abstract
For natural selection to operate there must exist heritable variation among individuals that affects their survival and reproduction. Among free-living microbes, where differences in growth rates largely define selection intensities, competitive exclusion is common. However, among surface attached communities, these dynamics become less predictable. If extreme circumstances were to dictate that a surface population is immortal and all offspring must emigrate, the offspring would be unable to contribute to the composition of the population. Meanwhile, the immortals, regardless of reproductive capacity, would remain unchanged in relative abundance. The normal cycle of birth, death, and competitive exclusion would be broken. We tested whether conditions required to set up this idealized scenario can be approximated in a microbial biofilm. Using two differentially-reproducing strains of Shewanella oneidensis grown on an anode as the sole terminal electron acceptor - a system in which metabolism is obligately tied to surface attachment - we found that selection against a slow-growing competitor is drastically reduced. This work furthers understanding of natural selection dynamics in sessile microbial communities, and provides a framework for designing stable microbial communities for industrial and experimental applications.
Collapse
Affiliation(s)
- Eric D Kees
- BioTechnology Institute, University of Minnesota, St Paul, MN, USA
- Department of Plant and Microbial Biology, University of Minnesota, St Paul, MN, USA
| | - Caleb E Levar
- BioTechnology Institute, University of Minnesota, St Paul, MN, USA
- Department of Plant and Microbial Biology, University of Minnesota, St Paul, MN, USA
| | - Stephen P Miller
- BioTechnology Institute, University of Minnesota, St Paul, MN, USA
- Department of Ecology, Evolution and Behavior, University of Minnesota, St Paul, MN, USA
| | - Daniel R Bond
- BioTechnology Institute, University of Minnesota, St Paul, MN, USA
- Department of Plant and Microbial Biology, University of Minnesota, St Paul, MN, USA
| | - Jeffrey A Gralnick
- BioTechnology Institute, University of Minnesota, St Paul, MN, USA.
- Department of Plant and Microbial Biology, University of Minnesota, St Paul, MN, USA.
| | - Antony M Dean
- BioTechnology Institute, University of Minnesota, St Paul, MN, USA.
- Department of Ecology, Evolution and Behavior, University of Minnesota, St Paul, MN, USA.
| |
Collapse
|
34
|
Starwalt-Lee R, El-Naggar MY, Bond DR, Gralnick JA. Electrolocation? The evidence for redox-mediated taxis in Shewanella oneidensis. Mol Microbiol 2020; 115:1069-1079. [PMID: 33200455 DOI: 10.1111/mmi.14647] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 11/11/2020] [Indexed: 11/27/2022]
Abstract
Shewanella oneidensis is a dissimilatory metal reducing bacterium and model for extracellular electron transfer (EET), a respiratory mechanism in which electrons are transferred out of the cell. In the last 10 years, migration to insoluble electron acceptors for EET has been shown to be nonrandom and tactic, seemingly in the absence of molecular or energy gradients that typically allow for taxis. As the ability to sense, locate, and respire electrodes has applications in bioelectrochemical technology, a better understanding of taxis in S. oneidensis is needed. While the EET conduits of S. oneidensis have been studied extensively, its taxis pathways and their interplay with EET are not yet understood, making investigation into taxis phenomena nontrivial. Since S. oneidensis is a member of an EET-encoding clade, the genetic circuitry of taxis to insoluble acceptors may be conserved. We performed a bioinformatic analysis of Shewanella genomes to identify S. oneidensis chemotaxis orthologs conserved in the genus. In addition to the previously reported core chemotaxis gene cluster, we identify several other conserved proteins in the taxis signaling pathway. We present the current evidence for the two proposed models of EET taxis, "electrokinesis" and flavin-mediated taxis, and highlight key areas in need of further investigation.
Collapse
Affiliation(s)
- Ruth Starwalt-Lee
- BioTechnology Institute and Department of Plant and Microbial Biology, University of Minnesota - Twin Cities, St. Paul, MN, USA
| | - Mohamed Y El-Naggar
- Department of Physics and Astronomy, University of Southern California, Los Angeles, CA, USA.,Department of Chemistry, University of Southern California, Los Angeles, CA, USA.,Molecular and Computational Biology Section, Department of Biological Sciences, University of Southern California, Los Angeles, CA, USA
| | - Daniel R Bond
- BioTechnology Institute and Department of Plant and Microbial Biology, University of Minnesota - Twin Cities, St. Paul, MN, USA
| | - Jeffrey A Gralnick
- BioTechnology Institute and Department of Plant and Microbial Biology, University of Minnesota - Twin Cities, St. Paul, MN, USA
| |
Collapse
|
35
|
Wang G, Tang K, Meng Z, Liu P, Mo S, Mehrjou B, Wang H, Liu X, Wu Z, Chu PK. A Quantitative Bacteria Monitoring and Killing Platform Based on Electron Transfer from Bacteria to a Semiconductor. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e2003616. [PMID: 32815249 DOI: 10.1002/adma.202003616] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 07/24/2020] [Indexed: 06/11/2023]
Abstract
A platform with both bacteria killing and sensing capabilities is crucial for monitoring the entire bacteria-related process on biomaterials and biomedical devices. Electron transfer (ET) between the bacteria and a Au-loaded semiconductor (ZnO) is observed to be the primary factor for effective bacteria sensing and fast bacteria killing. The electrons produce a saturation current that varies linearly with the bacteria number, semi-logarithmically, with R2 of 0.98825, thus providing an excellent tool to count bacteria quantitatively in real-time. Furthermore, ET leads to continuous electron loss killing of about 80% of Escherichia coli in only 1 h without light. The modularity and extendability of this ET-based platform are also demonstrated by the excellent results obtained from other semiconductor/substrate systems and the stability is confirmed by recycling tests. The underlying mechanism for the dual functions is not due to conventional attributed Zn2+ leaching or photocatalysis but instead electrical interactions upon direct contact. The results reveal the capability of real-time detection of bacteria based on ET while providing information about the antibacterial behavior of ZnO-based materials especially in the early stage. The concept can be readily incorporated into the design of smart and miniaturized devices that can sense and kill bacteria simultaneously.
Collapse
Affiliation(s)
- Guomin Wang
- Department of Physics, Department of Materials Science and Engineering, and Department of Biomedical Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, 999077, China
| | - Kaiwei Tang
- Department of Physics, Department of Materials Science and Engineering, and Department of Biomedical Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, 999077, China
| | - Zheyi Meng
- State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai, 201620, China
| | - Pei Liu
- Department of Physics, Department of Materials Science and Engineering, and Department of Biomedical Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, 999077, China
| | - Shi Mo
- Department of Physics, Department of Materials Science and Engineering, and Department of Biomedical Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, 999077, China
| | - Babak Mehrjou
- Department of Physics, Department of Materials Science and Engineering, and Department of Biomedical Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, 999077, China
| | - Huaiyu Wang
- Center for Human Tissues and Organs Degeneration, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Xuanyong Liu
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, China
| | - Zhengwei Wu
- Department of Physics, Department of Materials Science and Engineering, and Department of Biomedical Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, 999077, China
- Department of Engineering and Applied Physics, University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Paul K Chu
- Department of Physics, Department of Materials Science and Engineering, and Department of Biomedical Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, 999077, China
| |
Collapse
|
36
|
Wang G, Han N, Liu L, Ke Z, Li B, Chen G. Molecular density regulating electron transfer efficiency of S. oneidensis MR-1 mediated roxarsone biotransformation. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 262:114370. [PMID: 32443212 DOI: 10.1016/j.envpol.2020.114370] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 02/17/2020] [Accepted: 03/12/2020] [Indexed: 06/11/2023]
Abstract
Efficient extracellular electron transport is a key for sufficient bioremediation of organoarsenic pollutants such as 4-hydroxy-3-nitrobenzenearsonic acid (roxarsone). The related apparent kinetics characteristics are essential for engineering practice of bioremediation activities and for full understanding the environmental fate of roxarsone, yet remains poorly understood. We report, to our knowledge, the first study of the electron transfer characteristics between roxarsone and participating S. oneidensis MR-1. The electron transfer rate during roxarsone biotransformation was estimated up to 3.1 × 106 electrons/cell/s, with its value being clearly associated with the apparent roxarsone concentration. Lowing roxarsone concentration extended the average separation distance between cells and neighboring roxarsone molecules and thereby augmented electric resistance as well as extended cell movement for foraging, thus reduced electron transfer rate. In addition, the presence of roxarsone significantly stimulated population growth of S. oneidensis MR-1 with nearly doubled maximum specific growth rate, albeit with clearly increased lag time, as compared with that of none-roxarsone scenario. These findings provide, at the first time, basic biostoichiometry of S. oneidensis MR-1 induced roxarsone biotransformation, which may shed lights for full understanding of roxarsone transformation process in waste treatment systems that are necessary for engineering practice and/or environmental risks assessment.
Collapse
Affiliation(s)
- Gang Wang
- Department of Soil and Water Sciences, China Agricultural University, Beijing, 100193, China
| | - Neng Han
- Department of Soil and Water Sciences, China Agricultural University, Beijing, 100193, China
| | - Li Liu
- Department of Civil Engineering, Hefei University of Technology, Hefei, 230009, China
| | - Zhengchen Ke
- Department of Civil Engineering, Hefei University of Technology, Hefei, 230009, China
| | - Baoguo Li
- Department of Soil and Water Sciences, China Agricultural University, Beijing, 100193, China
| | - Guowei Chen
- Department of Civil Engineering, Hefei University of Technology, Hefei, 230009, China.
| |
Collapse
|
37
|
Zhao R, Chen G, Liu L, Zhang W, Sun Y, Li B, Wang G. Bacterial foraging facilitates aggregation of Chlamydomonas microsphaera in an organic carbon source-limited aquatic environment. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 259:113924. [PMID: 31926396 DOI: 10.1016/j.envpol.2020.113924] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 12/06/2019] [Accepted: 01/05/2020] [Indexed: 06/10/2023]
Abstract
Microalgal aggregation is a key to many ecosystem functions in aquatic environments. Yet mechanistic understanding of microalgae aggregation, especially the interactions with ubiquitous bacteria populations, remains elusive. We reported an experimental study illustrating how the emerging bacterial populations interacted with a model microalga (Chlamydomonas microsphaera) cells and the consequent aggregation patterns. Results showed that the emergence of bacterial populations significantly stimulated C. microsphaera aggregation. Both bacterial and C. microsphaera motilities were remarkably excited upon coculturing, with the mean cell velocity being up to 2.67 and 1.80 times of those of separate bacterial and C. microsphaera cultures, respectively. The stimulated bacterial and C. microsphaera cell velocity upon coculturing would likely provide a mechanism for enhanced probability of cell-cell collisions that led to amplified aggregation of C. microsphaera population. Correlation analysis revealed that bacterial resource foraging (for polysaccharides) was likely a candidate mechanism for stimulated cell motility in an organic carbon source-limited environment, whereby C. microsphaera-derived polysaccharides serve as the sole organic carbon source for heterotrophic bacteria which in turns facilitates bacteria-C. microsphaera aggregation. Additional analysis showed that bacterial populations capable of successive decomposing algal-derived organic matters dominated the cocultures, with the top five abundant genera of Brevundimonas (24.78%), Shinella (17.94%), Sphingopyxis (11.62%), Dongia (5.82%) and Hyphomicrobium (5.45%). These findings provide new insights into full understanding of microalgae-bacteria interactions and consequent microbial aggregation characteristics in aquatic ecosystems.
Collapse
Affiliation(s)
- Ranran Zhao
- Department of Civil Engineering, Hefei University of Technology, Hefei, 230009, China
| | - Guowei Chen
- Department of Civil Engineering, Hefei University of Technology, Hefei, 230009, China; State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing, 210098, China.
| | - Li Liu
- Department of Civil Engineering, Hefei University of Technology, Hefei, 230009, China
| | - Wei Zhang
- Department of Plant, Soil and Microbial Sciences, and Environmental Science and Policy Program, Michigan State University, East Lansing, MI, 48824, United States
| | - Yifei Sun
- Department of Soil and Water Sciences, China Agricultural University, Beijing, 100193, China
| | - Baoguo Li
- Department of Soil and Water Sciences, China Agricultural University, Beijing, 100193, China
| | - Gang Wang
- Department of Soil and Water Sciences, China Agricultural University, Beijing, 100193, China
| |
Collapse
|
38
|
Hou J, Huang L, Zhou P, Qian Y, Li N. Understanding the interdependence of strain of electrotroph, cathode potential and initial Cu(II) concentration for simultaneous Cu(II) removal and acetate production in microbial electrosynthesis systems. CHEMOSPHERE 2020; 243:125317. [PMID: 31722262 DOI: 10.1016/j.chemosphere.2019.125317] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 10/31/2019] [Accepted: 11/04/2019] [Indexed: 06/10/2023]
Abstract
Metallurgical microbial electrosynthesis systems (MES) are holding great promise for simultaneous heavy metal removal and acetate production from heavy metal-contaminated and organics-barren waters. How critical parameters of strain of electrotroph, cathode potential and initial heavy metal concentration affect MES performance, however, is not yet fully understood. Heavy metal of Cu(II) and four Cu(II)-tolerant electrotrophs (Stenotrophomonas maltophilia JY1, Citrobacter sp. JY3, Pseudomonas aeruginosa JY5 and Stenotrophomonas sp. JY6) were employed to evaluate MES performance at various cathode potentials (-900 or -600 mV vs. standard hydrogen electrode) and initial Cu(II) concentrations (60-120 mg L-1). Each electrotrophs exhibited incremental Cu(II) removals with increased Cu(II) at -900 mV, higher than at -600 mV or in the abiotic controls. Acetate production by JY1 and JY6 decreased with the increase in initial Cu(II), compared to an initial increase and a decrease thereafter for JY3 and JY5. For each electrotrophs, the biofilms than the planktonic cells released more amounts of extracellular polymeric substances (EPS) with a compositional diversity and stronger Cu(II) complexation at -900 mV. These were higher than at -600 mV, or in the controls either under open circuit conditions or in the absence of Cu(II). This work demonstrates the interdependence of strain of electrotroph, cathode potential and initial Cu(II) on simultaneous Cu(II) removal and acetate production through the release of different amounts of EPS with diverse composites, contributing to enhancing the controlled MES for efficient recovery of value-added products from Cu(II)-contaminated and organics-barren waters.
Collapse
Affiliation(s)
- Jiaxin Hou
- Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China
| | - Liping Huang
- Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China.
| | - Peng Zhou
- College of Chemistry, Dalian University of Technology, Dalian, 116024, China
| | - Yitong Qian
- Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China
| | - Ning Li
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian, 116024, China
| |
Collapse
|
39
|
Yang Z, Sun T, Subdiaga E, Obst M, Haderlein SB, Maisch M, Kretzschmar R, Angenent LT, Kappler A. Aggregation-dependent electron transfer via redox-active biochar particles stimulate microbial ferrihydrite reduction. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 703:135515. [PMID: 31761354 DOI: 10.1016/j.scitotenv.2019.135515] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 11/11/2019] [Accepted: 11/12/2019] [Indexed: 06/10/2023]
Abstract
Microbial Fe(III) reduction plays an important role for biogeochemical carbon and iron cycling in sediments and soils. Biochar is used as a soil amendment to increase fertility and lower N2O/CO2 emissions. It is redox-active and can stimulate microbial Fe(III) mineral reduction. It is currently unknown, however, how the aggregation of cells and Fe(III) minerals with biochar particles influence microbial Fe(III) reduction. Therefore, we determined rates and extent of ferrihydrite (Fh) reduction in S. oneidensis MR-1 cell suspensions with different particles sizes of wood-derived Swiss biochar and KonTiki biochar at different biochar/Fh ratios. We found that at small biochar particle size and high biochar/Fh ratios, the biochar, MR-1 cells and Fh closely aggregated, therefore addition of biochar stimulated electron transfer and microbial Fh reduction. In contrast, large biochar particles and low biochar/Fh ratios inhibited the electron transfer and Fe(III) reduction due to the lack of effective aggregation. These results suggest that for stimulating Fh reduction, a certain biochar particle size and biochar/Fh ratio is necessary leading to a close aggregation of all phases. This aggregation favors electron transfer from cells to Fh via redox cycling of the electron donating and accepting functional groups of biochar and via direct electron transfer through conductive biochar carbon matrices. These findings improve our understanding of electron transfer between microorganisms and Fe(III) minerals via redox-active biochar and help to evaluate the impact of biochar on electron transfer processes in the environment.
Collapse
Affiliation(s)
- Zhen Yang
- Geomicrobiology, Center for Applied Geoscience, University of Tuebingen, Germany
| | - Tianran Sun
- Environmental Biotechnology, Center for Applied Geoscience, University of Tuebingen, Germany
| | - Edisson Subdiaga
- Environmental Mineralogy and Chemistry, Center for Applied Geoscience, University of Tuebingen, Germany
| | - Martin Obst
- Experimental Biogeochemistry, University of Bayreuth, Germany
| | - Stefan B Haderlein
- Environmental Mineralogy and Chemistry, Center for Applied Geoscience, University of Tuebingen, Germany
| | - Markus Maisch
- Geomicrobiology, Center for Applied Geoscience, University of Tuebingen, Germany
| | - Ruben Kretzschmar
- Soil Chemistry Group, Institute of Biogeochemistry and Pollutant Dynamics, CHN, ETH, Zurich, Switzerland
| | - Largus T Angenent
- Environmental Biotechnology, Center for Applied Geoscience, University of Tuebingen, Germany
| | - Andreas Kappler
- Geomicrobiology, Center for Applied Geoscience, University of Tuebingen, Germany.
| |
Collapse
|
40
|
3D‐Enhanced, High‐Performing, Super‐hydrophobic and Electromagnetic‐Interference Shielding Fabrics Based on Silver Paint and Their Use in Antibacterial Applications. ChemistrySelect 2019. [DOI: 10.1002/slct.201901738] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
41
|
Zhao N, Treu L, Angelidaki I, Zhang Y. Exoelectrogenic Anaerobic Granular Sludge for Simultaneous Electricity Generation and Wastewater Treatment. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:12130-12140. [PMID: 31507167 DOI: 10.1021/acs.est.9b03395] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
A thick and electroactive biofilm is the key to the successful development of microbial electrochemical systems and technologies (METs). In this study, intact anaerobic granular sludge (AGS), which is a spherical and dense microbial association, was successfully demonstrated as a novel and efficient biocatalyst in METs such as microbial fuel cells. Three different strategies were explored to shift the microbial composition of AGS from methanogenic to exoelectrogenic microbes, including varying the external resistance and organic loading and manipulating the anode potential. Among all the strategies, only with positive anode potential, AGS was successfully shifted from methanogenic to exoelectrogenic conditions, as indicated by the significantly high current response (10.32 A/m2) and 100% removal of organic carbon from wastewater. Moreover, the AGS bioanode showed no significant decrease in current generation and organic removal at pH 5, indicating good tolerance of AGS to acidic conditions. Finally, 16S rRNA sequencing revealed the enrichment of exoelectrogens and inhibition of methanogens in the microbial community of AGS after anode potential control. This study provides a proof of concept for extracting electrical energy from organic wastes by exoelectrogenic AGS along with simultaneous wastewater treatment and meanwhile opens up a new paradigm to create an efficient and cost-effective exoelectrogenic biocatalyst for boosting the industrial application of METs.
Collapse
Affiliation(s)
- Nannan Zhao
- Department of Environmental Engineering , Technical University of Denmark , DK-2800 Lyngby , Denmark
| | - Laura Treu
- Department of Environmental Engineering , Technical University of Denmark , DK-2800 Lyngby , Denmark
| | - Irini Angelidaki
- Department of Environmental Engineering , Technical University of Denmark , DK-2800 Lyngby , Denmark
| | - Yifeng Zhang
- Department of Environmental Engineering , Technical University of Denmark , DK-2800 Lyngby , Denmark
| |
Collapse
|
42
|
Degradation performance and microbial community analysis of microbial electrolysis cells for erythromycin wastewater treatment. Biochem Eng J 2019. [DOI: 10.1016/j.bej.2019.02.008] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
|
43
|
Newsome L, Lopez Adams R, Downie HF, Moore KL, Lloyd JR. NanoSIMS imaging of extracellular electron transport processes during microbial iron(III) reduction. FEMS Microbiol Ecol 2019; 94:5033680. [PMID: 29878195 PMCID: PMC6041951 DOI: 10.1093/femsec/fiy104] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Accepted: 06/05/2018] [Indexed: 01/25/2023] Open
Abstract
Microbial iron(III) reduction can have a profound effect on the fate of contaminants in natural and engineered environments. Different mechanisms of extracellular electron transport are used by Geobacter and Shewanella spp. to reduce insoluble Fe(III) minerals. Here we prepared a thin film of iron(III)-(oxyhydr)oxide doped with arsenic, and allowed the mineral coating to be colonised by Geobacter sulfurreducens or Shewanella ANA3 labelled with 13C from organic electron donors. This preserved the spatial relationship between metabolically active Fe(III)-reducing bacteria and the iron(III)-(oxyhydr)oxide that they were respiring. NanoSIMS imaging showed cells of G. sulfurreducens were co-located with the iron(III)-(oxyhydr)oxide surface and were significantly more 13C-enriched compared to cells located away from the mineral, consistent with Geobacter species requiring direct contact with an extracellular electron acceptor to support growth. There was no such intimate relationship between 13C-enriched S. ANA3 and the iron(III)-(oxyhydr)oxide surface, consistent with Shewanella species being able to reduce Fe(III) indirectly using a secreted endogenous mediator. Some differences were observed in the amount of As relative to Fe in the local environment of G. sulfurreducens compared to the bulk mineral, highlighting the usefulness of this type of analysis for probing interactions between microbial cells and Fe-trace metal distributions in biogeochemical experiments.
Collapse
Affiliation(s)
- Laura Newsome
- Williamson Research Centre, School of Earth and Environmental Sciences, University of Manchester, Manchester, M13 9PL, UK
| | - Rebeca Lopez Adams
- Williamson Research Centre, School of Earth and Environmental Sciences, University of Manchester, Manchester, M13 9PL, UK
| | - Helen F Downie
- Williamson Research Centre, School of Earth and Environmental Sciences, University of Manchester, Manchester, M13 9PL, UK
| | - Katie L Moore
- School of Materials, University of Manchester, Manchester, M13 9PL, UK.,Photon Science Institute, University of Manchester, Manchester, M13 9PL, UK
| | - Jonathan R Lloyd
- Williamson Research Centre, School of Earth and Environmental Sciences, University of Manchester, Manchester, M13 9PL, UK
| |
Collapse
|
44
|
Liu L, Liu G, Zhou J, Wang J, Jin R. Cotransport of biochar and Shewanella oneidensis MR-1 in saturated porous media: Impacts of electrostatic interaction, extracellular electron transfer and microbial taxis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 658:95-104. [PMID: 30572219 DOI: 10.1016/j.scitotenv.2018.12.031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 11/17/2018] [Accepted: 12/04/2018] [Indexed: 06/09/2023]
Abstract
Biochar widely applied to soil can influence microbial community composition and participate in extracellular electron transfer (EET). However, little is known about the cotransport behaviors of bacteria and biochar in aquifer and soil-water environments, which can affect the fate and application performance of biochar. In this study, we found that in comparison to their individual transport behaviors, the mobilities of cotransporting Shewanella oneidensis MR-1 and biochar colloid (BC) were significantly inhibited. The decreasing colloidal mobilities at higher ionic strengths signified the importance of electrostatic interaction between cell and BC in cotransport. Moreover, the less suppressed cotransport of BC and mutants defective of EET and the elevated inhibition effects on cotransport by adding exogenous electron donor suggested the importance of EET. Difference in cotransport behavior was also observed with BC having different redox states. Compared with oxidized BC, reduced BC with higher hydrophobicity led to easier aggregation with cell and higher retention in column. More importantly, MR-1 exhibited EET-dependent taxis towards biochar, which also contributed to the enhanced heteroaggregation and decreased mobilities of cell and biochar. Our results highlight that metabolic activities of microbes towards abiotic colloids cannot be neglected when assessing their transport behaviors, especially in subsurface environments abounded with redox-active inorganic particles and microbes performing extracellular respiration.
Collapse
Affiliation(s)
- Lecheng Liu
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Guangfei Liu
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.
| | - Jiti Zhou
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Jing Wang
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Ruofei Jin
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| |
Collapse
|
45
|
Libberton B, Binz M, van Zalinge H, Nicolau DV. Efficiency of the flagellar propulsion of Escherichia coli in confined microfluidic geometries. Phys Rev E 2019; 99:012408. [PMID: 30780339 DOI: 10.1103/physreve.99.012408] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Indexed: 12/23/2022]
Abstract
Bacterial movement in confined spaces is routinely encountered either in a natural environment or in artificial structures. Consequently, the ability to understand and predict the behavior of motile bacterial cells in confined geometries is essential to many applications, spanning from the more classical, such as the management complex microbial networks involved in diseases, biomanufacturing, mining, and environment, to the more recent, such as single cell DNA sequencing and computation with biological agents. Fortunately, the development of this understanding can be helped by the decades-long advances in semiconductor microfabrication, which allow the design and the construction of complex confining structures used as test beds for the study of bacterial motility. To this end, here we use microfabricated channels with varying sizes to study the interaction of Escherichia coli with solid confining spaces. It is shown that an optimal channel size exists for which the hydrostatic potential allows the most efficient movement of the cells. The improved understanding of how bacteria move will result in the ability to design better microfluidic structures based on their interaction with bacterial movement.
Collapse
Affiliation(s)
- Ben Libberton
- Department of Electrical Engineering and Electronics, University of Liverpool, L69 3GJ Liverpool, United Kingdom
| | - Marie Binz
- Department of Electrical Engineering and Electronics, University of Liverpool, L69 3GJ Liverpool, United Kingdom
| | - Harm van Zalinge
- Department of Electrical Engineering and Electronics, University of Liverpool, L69 3GJ Liverpool, United Kingdom
| | - Dan V Nicolau
- Department of Electrical Engineering and Electronics, University of Liverpool, L69 3GJ Liverpool, United Kingdom
| |
Collapse
|
46
|
Zhao J, Lin Z, Fang S, Xie X, Wang H, Pang Z, Zhang J, Kong X, Lei M. Photoexcitation of self-n-doped fullerene ammonium halides: The role of halide ion and a possible synergistic dual-redox cycle mechanism within their aggregate. J Photochem Photobiol A Chem 2019. [DOI: 10.1016/j.jphotochem.2019.01.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
47
|
Pepè Sciarria T, Arioli S, Gargari G, Mora D, Adani F. Monitoring microbial communities' dynamics during the start-up of microbial fuel cells by high-throughput screening techniques. ACTA ACUST UNITED AC 2019; 21:e00310. [PMID: 30805299 PMCID: PMC6374581 DOI: 10.1016/j.btre.2019.e00310] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 01/08/2019] [Accepted: 01/17/2019] [Indexed: 12/30/2022]
Abstract
Microbial Electrochemical Technologies are based on the use of electrochemically active microorganisms that can carry out extracellular electron transfer to an electrode while they are oxidizing the organic compounds. The dynamics and changes of the bacterial community in the anode biofilm and planktonic broth of an acetate fed batch single chamber air cathode MFC have been studied by combing flow-cytometry and Illumina sequencing techniques. At the beginning of the test, from 0 h to 70 h, microbial planktonic communities changed from four groups to two groups, as revealed by DNA content, and from three groups to one group based on the cell membrane polarization revealed by a DiOC6(3) probe. Between 4th day and 13th day, microbial communities changed from one group to a maximum of three groups, monitoring DNA content, and from one group to two based on the cell membrane polarization. The 16S rDNA gene profiling confirmed the shift in microbial communities, with Acinetobacter (39.34%), Azospirillum (27.66%), Arcobacter (4.17%) and Comamonas (2.62%) being the most abundant genera at the beginning of MFC activation. After 70 h the main genera detected were Azospirillum (46.42%), Acinetobacter (34.66%), Enterococcus (2.32%), Dysgonomonas (2.14%). Data obtained have shown that flow cytometry and illumina sequencing are useful tools to monitor "online" the changes in microbial communities during the MFCs start-up and the increase of Azospirillum and Acinetobacter genera is in good agreement with the MFC voltage generation. Moreover, monitoring planktonic populations, instead of the less accessible anode biofilm, was in good agreement with the evolution of MFC voltage.
Collapse
Affiliation(s)
- Tommy Pepè Sciarria
- Gruppo Ricicla, Department of Agriculture and Environmental Science, University of Milan, Milano, Italy
| | - Stefania Arioli
- Department of Food Environmental and Nutritional Sciences, University of Milan, Milano, Italy
| | - Giorgio Gargari
- Department of Food Environmental and Nutritional Sciences, University of Milan, Milano, Italy
| | - Diego Mora
- Department of Food Environmental and Nutritional Sciences, University of Milan, Milano, Italy
| | - Fabrizio Adani
- Gruppo Ricicla, Department of Agriculture and Environmental Science, University of Milan, Milano, Italy
| |
Collapse
|
48
|
Abstract
Previous hypotheses of tactic behavior of exoelectrogenic bacteria are based on techniques that do not accurately control the electrochemical potential, such as chemical-in-plug assays or microscopy tracking experiments in two-electrode cells. Here, we have revisited previous experiments and, for the first time, performed microscopy cell-tracking experiments in three-electrode electrochemical cells, with defined electrode potentials. Based on these experiments, taxis toward electrodes is observed to switch at about −0.2 V versus standard hydrogen electrode (SHE), coinciding with the reduction potential of flavins. Exoelectrogenic bacteria are defined by their ability to respire on extracellular and insoluble electron acceptors and have applications in bioremediation and microbial electrochemical systems (MESs), while playing important roles in biogeochemical cycling. Shewanella oneidensis MR-1, which has become a model organism for the study of extracellular respiration, is known to display taxis toward insoluble electron acceptors, including electrodes. Multiple mechanisms have been proposed for MR-1’s tactic behavior, and, here, we report on the role of electrochemical potential by video microscopy cell tracking experiments in three-electrode electrochemical cells. MR-1 trajectories were determined using a particle tracking algorithm and validated with Shannon’s entropy method. Tactic response by MR-1 in the electrochemical cell was observed to depend on the applied potential, as indicated by the average velocity and density of motile (>4 µm/s) MR-1 close to the electrode (<50 µm). Tactic behavior was observed at oxidative potentials, with a strong switch between the potentials −0.15 to −0.25 V versus the standard hydrogen electrode (SHE), which coincides with the reduction potential of flavins. The average velocity and density of motile MR-1 close to the electrode increased when riboflavin was added (2 µM), but were completely absent in a ΔmtrC/ΔomcA mutant of MR-1. Besides flavin’s function as an electron mediator to support anaerobic respiration on insoluble electron acceptors, we propose that riboflavin is excreted by MR-1 to sense redox gradients in its environment, aiding taxis toward insoluble electron acceptors, including electrodes in MESs.
Collapse
|
49
|
Paquete CM, Rusconi G, Silva AV, Soares R, Louro RO. A brief survey of the "cytochromome". Adv Microb Physiol 2019; 75:69-135. [PMID: 31655743 DOI: 10.1016/bs.ampbs.2019.07.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Multihaem cytochromes c are widespread in nature where they perform numerous roles in diverse anaerobic metabolic pathways. This is achieved in two ways: multihaem cytochromes c display a remarkable diversity of ways to organize multiple hemes within the protein frame; and the hemes possess an intrinsic reactive versatility derived from diverse spin, redox and coordination states. Here we provide a brief survey of multihaem cytochromes c that have been characterized in the context of their metabolic role. The contribution of multihaem cytochromes c to dissimilatory pathways handling metallic minerals, nitrogen compounds, sulfur compounds, organic compounds and phototrophism are described. This aims to set the stage for the further exploration of the vast unknown "cytochromome" that can be anticipated from genomic databases.
Collapse
|
50
|
Li B, Ma J, Wang D, Liu X, Li H, Zhou L, Liang C, Wang H. Self-adjusting antibacterial properties of Ag-incorporated nanotubes on micro-nanostructured Ti surfaces. Biomater Sci 2019; 7:4075-4087. [DOI: 10.1039/c9bm00862d] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The bactericidal activity of a silver loading platform in the “release” mode during the early phase and “contact” mode thereafter.
Collapse
Affiliation(s)
- Baoe Li
- School of Materials Science and Engineering
- Hebei University of Technology
- Tianjin 300130
- China
| | - Jianwei Ma
- School of Materials Science and Engineering
- Hebei University of Technology
- Tianjin 300130
- China
| | - Donghui Wang
- School of Materials Science and Engineering
- Hebei University of Technology
- Tianjin 300130
- China
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure
| | - Xuanyong Liu
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure
- Shanghai Institute of Ceramics
- Chinese Academy of Sciences
- Shanghai 200050
- China
| | - Haipeng Li
- School of Materials Science and Engineering
- Hebei University of Technology
- Tianjin 300130
- China
| | - Linxi Zhou
- School of Materials Science and Engineering
- Hebei University of Technology
- Tianjin 300130
- China
| | - Chunyong Liang
- School of Materials Science and Engineering
- Hebei University of Technology
- Tianjin 300130
- China
| | - Hongshui Wang
- School of Materials Science and Engineering
- Hebei University of Technology
- Tianjin 300130
- China
| |
Collapse
|