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Xu G, Yang H, Han J, Liu X, Shao K, Li X, Wang G, Yue W, Dou J. Regulatory roles of extracellular polymeric substances in uranium reduction via extracellular electron transfer by Desulfovibrio vulgaris UR1. ENVIRONMENTAL RESEARCH 2024; 262:119862. [PMID: 39208974 DOI: 10.1016/j.envres.2024.119862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2024] [Revised: 08/18/2024] [Accepted: 08/26/2024] [Indexed: 09/04/2024]
Abstract
The pathway of reducing U(VI) to insoluble U(IV) using electroactive bacteria has become an effective and promising approach to address uranium-contaminated water caused by human activities. However, knowledge regarding the roles of extracellular polymeric substances (EPS) in the uranium reduction process involving in extracellular electron transfer (EET) mechanisms is limited. Here, this study isolated a novel U(VI)-reducing strain, Desulfovibrio vulgaris UR1, with a high uranium removal capacity of 2.75 mM/(g dry cell). Based on a reliable EPS extraction method (45 °C heating), manipulation of EPS in D. vulgaris UR1 suspensions (removal or addition of EPS) highlighted its critical role in facilitating uranium reduction efficiency. On the second day, U(VI) removal rates varied significantly across systems with different EPS contents: 60.8% in the EPS-added system, 48.5% in the pristine system, and 22.2% in the EPS-removed system. Characterization of biogenic solids confirmed the reduction of U(VI) by D. vulgaris UR1, and the main products were uraninite and UO2 (2.88-4.32 nm in diameter). As EPS formed a permeable barrier, these nanoparticles were primarily immobilized within the EPS in EPS-retained/EPS-added cells, and within the periplasm in EPS-removed cells. Multiple electroactive substances, such as tyrosine/tryptophan aromatic compounds, flavins, and quinone-like substances, were identified in EPS, which might be the reason for enhancement of uranium reduction via providing more electron shuttles. Furthermore, proteomics revealed that a large number of proteins in EPS were enriched in the subcategories of catalytic activity and electron transfer activity. Among these, iron-sulfur proteins, such as hydroxylamine reductase (P31101), pyruvate: ferredoxin oxidoreductase (A0A0H3A501), and sulfite reductase (P45574), played the most critical role in regulating EET in D. vulgaris UR1. This work highlighted the importance of EPS in the uranium reduction by D. vulgaris UR1, indicating that EPS functioned as both a reducing agent and a permeation barrier for access to heavy metal uranium.
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Affiliation(s)
- Guangming Xu
- Engineering Research Center of Ministry of Education on Groundwater Pollution Control and Remediation, College of Water Sciences, Beijing Normal University, Beijing 100875, PR China
| | - Haotian Yang
- Engineering Research Center of Ministry of Education on Groundwater Pollution Control and Remediation, College of Water Sciences, Beijing Normal University, Beijing 100875, PR China
| | - Juncheng Han
- Engineering Research Center of Ministry of Education on Groundwater Pollution Control and Remediation, College of Water Sciences, Beijing Normal University, Beijing 100875, PR China
| | - Xinyao Liu
- Engineering Research Center of Ministry of Education on Groundwater Pollution Control and Remediation, College of Water Sciences, Beijing Normal University, Beijing 100875, PR China
| | - Kexin Shao
- Engineering Research Center of Ministry of Education on Groundwater Pollution Control and Remediation, College of Water Sciences, Beijing Normal University, Beijing 100875, PR China
| | - Xindai Li
- Engineering Research Center of Ministry of Education on Groundwater Pollution Control and Remediation, College of Water Sciences, Beijing Normal University, Beijing 100875, PR China
| | - Guanying Wang
- Engineering Research Center of Ministry of Education on Groundwater Pollution Control and Remediation, College of Water Sciences, Beijing Normal University, Beijing 100875, PR China; Beijing Boqi Electric Power Science and Technology Co., Ltd, Beijing 100012, PR China
| | - Weifeng Yue
- Engineering Research Center of Ministry of Education on Groundwater Pollution Control and Remediation, College of Water Sciences, Beijing Normal University, Beijing 100875, PR China.
| | - Junfeng Dou
- Engineering Research Center of Ministry of Education on Groundwater Pollution Control and Remediation, College of Water Sciences, Beijing Normal University, Beijing 100875, PR China.
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Sun H, Zhou ZJ, Wen HQ, Chen FF, Pan Y, Tang Q, Yu HQ. Deciphering the Roles of Extracellular Polymeric Substances (EPS) in Shaping Disinfection Kinetics through Permanent Removal via Genetic Disruption. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:6552-6563. [PMID: 38571383 DOI: 10.1021/acs.est.4c01612] [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: 04/05/2024]
Abstract
Extracellular polymeric substances (EPS) ubiquitously encapsulate microbes and play crucial roles in various environmental processes. However, understanding their complex interactions with dynamic bacterial behaviors, especially during the disinfection process, remains very limited. In this work, we investigated the impact of EPS on bacterial disinfection kinetics by developing a permanent EPS removal strategy. We genetically disrupted the synthesis of exopolysaccharides, the structural components of EPS, in Pseudomonas aeruginosa, a well-known EPS-producing opportunistic pathogen found in diverse environments, creating an EPS-deficient strain. This method ensured a lasting absence of EPS while maintaining bacterial integrity and viability, allowing for real-time in situ investigations of the roles of EPS in disinfection. Our findings indicate that removing EPS from bacteria substantially lowered their susceptibility threshold to disinfectants such as ozone, chloramine B, and free chlorine. This removal also substantially accelerated disinfection kinetics, shortened the resistance time, and increased disinfection efficiency, thereby enhancing the overall bactericidal effect. The absence of EPS was found to enhance bacterial motility and increase bacterial cell vulnerability to disinfectants, resulting in greater membrane damage and intensified reactive oxygen species (ROS) production upon exposure to disinfectants. These insights highlight the central role of EPS in bacterial defenses and offer promising implications for developing more effective disinfection strategies.
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Gao H, Chen N, An N, Zhan Y, Wang H, Feng C. Harnessing the potential of ginkgo biloba extract: Boosting denitrification performance through accelerated electron transfer. CHEMOSPHERE 2024; 352:141368. [PMID: 38316282 DOI: 10.1016/j.chemosphere.2024.141368] [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: 11/18/2023] [Revised: 01/14/2024] [Accepted: 02/02/2024] [Indexed: 02/07/2024]
Abstract
Ginkgo biloba extract (GBE) had several effects on the human body as one of the widely used phytopharmaceuticals, but it had no application in microbial enhancement in the environmental field. The study focused on the impact of GBE on denitrification specifically under neutral conditions. At the identified optimal addition ratio of 2% (v/v), the system exhibited a noteworthy increase in nitrate reduction rate (NRR) by 56.34%, elevating from 0.71 to 1.11 mg-N/(L·h). Moreover, the extraction of microbial extracellular polymeric substance (EPS) at this ratio revealed changes in the composition of EPS, the electron exchange capacity (EEC) was enhanced from 87.16 to 140.4 μmol/(g C), and the transfer impedance was reduced within the EPS. The flavin, fulvic acid (FA), and humic acid (HA) provided a π-electron conjugated structure for the denitrification system, enhancing extracellular electron transfer (EET) by stimulating carbon source metabolism. GBE also improved electron transfer system activity (ETSA) from 0.025 to 0.071 μL O2/(g·min·prot) and the content of NADH enhanced by 22.90% while significantly reducing the activation energy (Ea) by 85.6% in the denitrification process. The synergy of improving both intracellular and extracellular electron transfer, along with the reduction of Ea, notably amplified the initiation and reduction rates of the denitrification process. Additionally, GBE demonstrated suitability for denitrification across various pH levels, enhancing microbial resilience in alkaline conditions and promoting survival and proliferation. Overall, these findings open the door to potential applications of GBE as a natural additive in the environmental field to improve the efficiency of denitrification processes, which are essential for nitrogen removal in various environmental contexts.
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Affiliation(s)
- Hang Gao
- School of Water Resources and Environment, MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), Beijing, 100083, China
| | - Nan Chen
- School of Water Resources and Environment, MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), Beijing, 100083, China.
| | - Ning An
- School of Water Resources and Environment, MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), Beijing, 100083, China
| | - Yongheng Zhan
- School of Water Resources and Environment, MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), Beijing, 100083, China
| | - Haishuang Wang
- School of Water Resources and Environment, MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), Beijing, 100083, China
| | - Chuanping Feng
- School of Water Resources and Environment, MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), Beijing, 100083, China
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Zhang S, Li C, Ke C, Liu S, Yao Q, Huang W, Dang Z, Guo C. Extracellular polymeric substances sustain photoreduction of Cr(VI) by Shewanella oneidensis-CdS biohybrid system. WATER RESEARCH 2023; 243:120339. [PMID: 37482009 DOI: 10.1016/j.watres.2023.120339] [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: 06/20/2023] [Accepted: 07/11/2023] [Indexed: 07/25/2023]
Abstract
Photosensitized biohybrid system (PBS) enables bacteria to exploit light energy harvested by semiconductors for rapid pollutants transformation, possessing a promising future for water reclamation. Maintaining a biocompatible environment under photocatalytic conditions is the key to developing PBS-based treatment technologies. Natural microbial cells are surrounded by extracellular polymeric substances (EPS) that either be tightly bound to the cell wall (i.e., tightly bound EPS, tbEPS) or loosely associated with cell surface (i.e., loosely bound EPS, lbEPS), which provide protection from unfavorable environment. We hypothesized that providing EPS fractions can enhance bacterial viability under adverse environment created by photocatalytic reactions. We constructed a model PBS consisting of Shewanella oneidensis and CdS using Cr(VI) as the target pollutant. Results showed complete removal of 25 mg/L Cr(VI) within 90 min without an electron donor, which may mainly rely on the synergistic effect of CdS and bacteria on photoelectron transfer. Long-term cycling experiment of pristine PBS and PBS with extra EPS fractions (including lbEPS and tbEPS) for Cr(VI) treatment showed that PBS with extra lbEPS achieved efficient Cr(VI) removal within five consecutive batch treatment cycles, compared to the three cycles both in pristine PBS and PBS with tbEPS. After addition of lbEPS, the accumulation of reactive oxygen species (ROS) was greatly reduced via the EPS-capping effect and quenching effect, and the toxic metal internalization potential was lowered by complexation with Cd and Cr, resulting in enhanced bacterial viability during photocatalysis. This facile and efficient cytoprotective method helps the rational design of PBS for environmental remediation.
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Affiliation(s)
- Siyu Zhang
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou 510006, China
| | - Changhao Li
- Hospital of Stomatology, Guanghua School of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou 510055, China
| | - Changdong Ke
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou 510006, China
| | - Sijia Liu
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou 510006, China
| | - Qian Yao
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou 510006, China
| | - Weilin Huang
- Department of Environmental Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901, USA
| | - Zhi Dang
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou 510006, China; Guangdong Provincial Key Lab of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou 510006, China
| | - Chuling Guo
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, Guangzhou 510006, China.
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Zhou Y, Xue C, Gan L, Owens G, Chen Z. Simultaneous removal of triclosan and Cd(Ⅱ) by bio-reduced graphene oxide and its mechanism. CHEMOSPHERE 2023; 311:137021. [PMID: 36326514 DOI: 10.1016/j.chemosphere.2022.137021] [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: 08/22/2022] [Revised: 10/18/2022] [Accepted: 10/23/2022] [Indexed: 06/16/2023]
Abstract
The co-existence of contaminants such as triclosan (TCS) and Cadmium in wastewater is a major public health problem because of their persistence and toxicity. In this study, bio-reduced graphene oxide (B-rGO) synthesized by Lysinibacillus sp. Simultaneously remove TCS and Cd(II), with adsorption capacities of 81.91 and 23.32 mg g-1, for TCS and Cd (Ⅱ), respectively. This was significantly higher than that previously reported for commercially available reduced graphene oxide (C-rGO), which was only 31.94 and 2.01 mg g-1, for TCS and Cd (Ⅱ), respectively. Fourier transform infrared spectroscopy (FTIR) showed that rGO surface-bound extracellular polymeric substances (EPS) played a key role in the observed enhanced contaminant removal, which was verified by scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and X-ray photoelectron spectroscopy (XPS). In addition, the absorption of both Cd(II) and TCS on B-rGO was confirmed by XPS and high-performance liquid chromatography (HPLC-UV). The adsorption kinetics of both TCS and Cd(II) fitted well to the pseudo-second-order model, while the adsorption isotherms of Cd(II) followed the Langmuir model, and triclosan the Freundlich model. A mechanism of simultaneous removal of TCS was proposed based on π-π interactions and hydrogen bonding, while Cd(II) was removed by a combination of electrostatic and chelation/complexation. Finally, the adsorption of TCS and Cd(II) by B-rGO in real wastewater was shown to be 76.67 and 16.53 mg g-1, respectively, demonstrating that B-rGO has the potential for practical simultaneous removal of TCS and Cd(II) from wastewater.
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Affiliation(s)
- Yuanyuan Zhou
- Fujian Key Laboratory of Pollution Control and Resource Reuse; School of Environmental Science and Engineering, Fujian Normal University, Fuzhou 350007, Fujian Province, China
| | - Chao Xue
- Fujian Key Laboratory of Pollution Control and Resource Reuse; School of Environmental Science and Engineering, Fujian Normal University, Fuzhou 350007, Fujian Province, China
| | - Li Gan
- Fujian Key Laboratory of Pollution Control and Resource Reuse; School of Environmental Science and Engineering, Fujian Normal University, Fuzhou 350007, Fujian Province, China.
| | - Gary Owens
- Environmental Contaminants Group, Future Industries Institute, University of South Australia, Mawson Lakes, SA 5095, Australia
| | - Zuliang Chen
- Fujian Key Laboratory of Pollution Control and Resource Reuse; School of Environmental Science and Engineering, Fujian Normal University, Fuzhou 350007, Fujian Province, China.
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Nie X, Lin Q, Dong F, Cheng W, Ding C, Wang J, Liu M, Chen G, Zhou Y, Li X, Boyanov MI, Kemner KM. Surface biomineralization of uranium onto Shewanella putrefaciens with or without extracellular polymeric substances. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2022; 241:113719. [PMID: 35691198 DOI: 10.1016/j.ecoenv.2022.113719] [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: 03/15/2022] [Revised: 05/16/2022] [Accepted: 05/28/2022] [Indexed: 06/15/2023]
Abstract
The influence of extracellular polymeric substances (EPS) on the interaction between uranium [U(VI)] and Shewanella putrefaciens (S. putrefaciens), especially the U(VI) biomineralization process occurring on whole cells and cell components of S. putrefaciens was investigated in this study. The removal efficiency of U(VI) by S. putrefaciens was decreased by 22% after extraction of EPS. Proteins were identified as the main components of EPS by EEM analysis and were determined to play a major role in the biosorption of uranium. SEM-EDS results showed that U(VI) was distributed around the whole cell as 500-nanometer schistose structures, which consisted primarily of U and P. However, similar uranium lamellar crystal were wrapped only on the surface of EPS-free S. putrefaciens cells. FTIR and XPS analysis indicated that phosphorus- and nitrogen-containing groups played important roles in complexing U (VI). XRD and U LIII-edge EXAFS analyses demonstrated that the schistose structure consisted of hydrogen uranyl phosphate [H2(UO2)2(PO4)2•8H2O]. Our study provides new insight into the mechanisms of induced uranium crystallization by EPS and cell wall membranes of living bacterial cells under aerobic conditions.
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Affiliation(s)
- Xiaoqin Nie
- National Collaborative Innovation Center for Nuclear Waste and Environmental Safety, Southwest University of Science and Technology, Mianyang 621010, China; Fundamental Science on Nuclear Wastes and Environmental Safety Laboratory, Southwest University of Science and Technology, Mianyang 621010, China; Mianyang Central Hospital, NHC Key Laboratory of Nuclear Technology Medical Transformation,Mianyang 621000, China.
| | - Qiaoya Lin
- National Collaborative Innovation Center for Nuclear Waste and Environmental Safety, Southwest University of Science and Technology, Mianyang 621010, China; Sino-French Institute of Nuclear Engineering and Technology, Sun Yat-sen University, Zhuhai 519082, China
| | - Faqin Dong
- National Collaborative Innovation Center for Nuclear Waste and Environmental Safety, Southwest University of Science and Technology, Mianyang 621010, China; Key Laboratory of Solid Waste Treatment and Resource Recycle, Ministry of Education, Southwest University of Science and Technology, Mianyang 621010, China
| | - Wencai Cheng
- National Collaborative Innovation Center for Nuclear Waste and Environmental Safety, Southwest University of Science and Technology, Mianyang 621010, China
| | - Congcong Ding
- Fundamental Science on Nuclear Wastes and Environmental Safety Laboratory, Southwest University of Science and Technology, Mianyang 621010, China
| | - Junling Wang
- Fundamental Science on Nuclear Wastes and Environmental Safety Laboratory, Southwest University of Science and Technology, Mianyang 621010, China
| | - Mingxue Liu
- National Collaborative Innovation Center for Nuclear Waste and Environmental Safety, Southwest University of Science and Technology, Mianyang 621010, China
| | - Guozheng Chen
- Mianyang Central Hospital, NHC Key Laboratory of Nuclear Technology Medical Transformation,Mianyang 621000, China
| | - Yan Zhou
- Mianyang Central Hospital, NHC Key Laboratory of Nuclear Technology Medical Transformation,Mianyang 621000, China
| | - Xiaoan Li
- Mianyang Central Hospital, NHC Key Laboratory of Nuclear Technology Medical Transformation,Mianyang 621000, China.
| | - Maxim I Boyanov
- Biosciences Division, Argonne National Laboratory, Argonne, IL 60439, USA; Bulgarian Academy of Sciences, Institute of Chemical Engineering, Sofia 1113, Bulgaria
| | - Kenneth M Kemner
- Biosciences Division, Argonne National Laboratory, Argonne, IL 60439, USA
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Wang N, Feng Y, Li Y, Zhang L, Liu J, Li N, He W. Effects of ammonia on electrochemical active biofilm in microbial electrolysis cells for synthetic swine wastewater treatment. WATER RESEARCH 2022; 219:118570. [PMID: 35597221 DOI: 10.1016/j.watres.2022.118570] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 04/28/2022] [Accepted: 05/05/2022] [Indexed: 06/15/2023]
Abstract
When facing wastewater with high organic and ammonia, e. g. swine wastewater, microbial electrolysis cell (MEC) is emerging for energy extraction as hydrogen and methane. However, the effects of highly concentrated ammonia on MEC haven't been fully evaluated. In this study, single-chamber MECs were operated with acetate and sucrose as substrates under various ammonia concentrations. The current generally increased with ammonia loading from 80 to 3000 mg L-1. Yet, the substrate consumption in MECs was inhibited with ammonia concentrations above 1000 mg L-1. As a combined result, the energy recovery efficiency of MECs was stable. The electrochemical activity of anode biofilm reached the peak under 1000 mg L-1 ammonia and was restricted under higher ammonia loadings. Under neutral pH, the NH4+ increases the cell membrane permeability, which benefited the electrochemical activity of exoelectrogens to a proper extent. Nevertheless, the toxic ammonia also accelerated the anode biomass loss and stimulated the extracellular polymeric substance (EPS) secretion. Due to the current increase, the abundance of exoelectrogens generally raised with ammonia loading from 80 to 3000 mg L-1. However, except for anode biomass loss, the carbon and methane metabolism pathways were inhibited in acetate-fed MEC, while the glycolysis acted as the rate-limiting step for substrate degradation in sucrose-fed conditions. This study systematically examined the influences of high ammonia loading on MEC performances, bio-community and anode electrochemical activities, and evaluated practical feasibility and application inch of MECs for the energy recovery and pollutant removal of high concentration organic and ammonia wastewater.
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Affiliation(s)
- Naiyu Wang
- School of Environmental Science and Engineering, Academy of Ecology and Environment, Tianjin University, No. 92 Weijin Road, Nankai District, Tianjin 300072, PR China
| | - Yujie Feng
- School of Environmental Science and Engineering, Academy of Ecology and Environment, Tianjin University, No. 92 Weijin Road, Nankai District, Tianjin 300072, PR China.
| | - Yunfei Li
- School of Environmental Science and Engineering, Academy of Ecology and Environment, Tianjin University, No. 92 Weijin Road, Nankai District, Tianjin 300072, PR China
| | - Lijuan Zhang
- School of Environment and Energy, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou, Guangdong 510006, PR China
| | - Jia Liu
- School of Environmental Science and Engineering, Academy of Ecology and Environment, Tianjin University, No. 92 Weijin Road, Nankai District, Tianjin 300072, PR China
| | - Nan Li
- School of Environmental Science and Engineering, Academy of Ecology and Environment, Tianjin University, No. 92 Weijin Road, Nankai District, Tianjin 300072, PR China
| | - Weihua He
- School of Environmental Science and Engineering, Academy of Ecology and Environment, Tianjin University, No. 92 Weijin Road, Nankai District, Tianjin 300072, PR China.
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Extracellular Polymeric Substances and Biocorrosion/Biofouling: Recent Advances and Future Perspectives. Int J Mol Sci 2022; 23:ijms23105566. [PMID: 35628373 PMCID: PMC9143384 DOI: 10.3390/ijms23105566] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 05/10/2022] [Accepted: 05/13/2022] [Indexed: 11/17/2022] Open
Abstract
Microbial cells secrete extracellular polymeric substances (EPS) to adhere to material surfaces, if they get in contact with solid materials such as metals. After phase equilibrium, microorganisms can adhere firmly to the metal surfaces causing metal dissolution and corrosion. Attachment and adhesion of microorganisms via EPS increase the possibility and the rate of metal corrosion. Many components of EPS are electrochemical and redox active, making them closely related to metal corrosion. Functional groups in EPS have specific adsorption ability, causing them to play a key role in biocorrosion. This review emphasizes EPS properties related to metal corrosion and protection and the underlying microbially influenced corrosion (MIC) mechanisms. Future perspectives regarding a comprehensive study of MIC mechanisms and green methodologies for corrosion protection are provided.
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Zhao M, Bai X, Zhang Y, Yuan Y, Sun J. Enhanced photodegradation of antibiotics based on anoxygenic photosynthetic bacteria and bacterial metabolites: A sustainably green strategy for the removal of high-risk organics from secondary effluent. JOURNAL OF HAZARDOUS MATERIALS 2022; 430:128350. [PMID: 35149498 DOI: 10.1016/j.jhazmat.2022.128350] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 01/13/2022] [Accepted: 01/23/2022] [Indexed: 06/14/2023]
Abstract
Antibiotic residues in effluents discharged from wastewater treatment plants (WWTPs) have been considered high-risk organics due to biorefractory property and potential toxicity. Secondary pollution and unsustainability existed in advanced treatment of secondary effluent are currently in urgent need of improvement. In this study, a sustainably green strategy based on Rhodopseudomonas palustris (R.palustris) by regulating the structure of extracellular polymeric substances (EPS) was proposed for the first time to achieve efficiently removal of sulfadiazine (SDZ). Results showed that 0.2 V was the optimal external potential for R.palustris to efficiently remove SDZ, where the biodegradation rate constant obtained at this potential was 4.87-folds higher than that in open-circuit mode and a complete removal was achieved within 58 h in the presence of EPS extracted at this potential. Three-dimensional excitation-emission matrix (3D-EEM) spectra analysis suggested that tryptophan protein-like, tyrosine protein-like, humic acid-like and fulvic acid-like substances present in EPS were the main effective components which was responsible for the indirect photodegradation of SDZ. The quenching experiments showed that 3EPS* was the dominant reactive species which accounted for 90% of SDZ removal. This study provides new implications for the advanced treatment of secondary effluent organic matters by developing eco-friendly bioaugmentation technology and biomaterials.
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Affiliation(s)
- Mengmeng Zhao
- Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, School of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China
| | - Xiaoyan Bai
- Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, School of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China
| | - Yaping Zhang
- Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, School of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China
| | - Yong Yuan
- Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, School of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China
| | - Jian Sun
- Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, School of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China.
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Wen L, Huang L, Wang Y, Yuan Y, Zhou L. Facet-engineered hematite boosts microbial electrogenesis by synergy of promoting electroactive biofilm formation and extracellular electron transfer. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 819:153154. [PMID: 35038509 DOI: 10.1016/j.scitotenv.2022.153154] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 01/10/2022] [Accepted: 01/11/2022] [Indexed: 06/14/2023]
Abstract
Hematite has been proven to be an excellent material for enhancing extracellular electron transfer (EET) in microbial bioelectrochemical systems (BESs). However, the effect of hematite with different exposed facets on microbial EET remains unclear. Here, we synthesized two types of hematite nanoparticles with high {100} and {001} facet exposure (Hem_{100} and Hem_{001}), respectively, which were coated on ITO electrode to stimulate the microbial EET in the BESs. The results showed that the maximum biocurrent density of commercial hematite nanoparticles (Hem_NPs), Hem_{100} and Hem_{001} electrodes reached 73.33 ± 5.68, 129.33 ± 9.12 and 287.00 ± 19.89 μA cm-2 from three replicates of each treatment, respectively. The current generation achieved from the Hem_{001} electrode was nearly 199-times higher than that of the blank ITO electrode (1.44 ± 0.10 μA cm-2). The electrochemical measurements showed that the lowest charge transfer resistance (Rct) was observed for the Hem_{001}, and the promoted biofilm formation and EPS secretion on the Hem_{001} electrode were also revealed, which could contribute the high performance of this electrode. Moreover, metagenomic analysis revealed that Hem_{001} might facilitate the microbial EET by stimulating the expression of genes related to cytochrome c and conductive nanowires. This study not only provides a new strategy to enhance microbial electrogenesis but also expands the knowledge of the effect of facet on microbial EET, helping to develop more efficient electrode materials in the future.
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Affiliation(s)
- Liumei Wen
- Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Guangzhou Key Laboratory Environmental Catalysis and Pollution Control, School of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, PR China
| | - Lingyan Huang
- Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Guangzhou Key Laboratory Environmental Catalysis and Pollution Control, School of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, PR China
| | - Yi Wang
- Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Guangzhou Key Laboratory Environmental Catalysis and Pollution Control, School of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, PR China
| | - Yong Yuan
- Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Guangzhou Key Laboratory Environmental Catalysis and Pollution Control, School of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, PR China
| | - Lihua Zhou
- Department of Pharmaceutical Engineering, School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou 510006, PR China.
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11
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Lim K, Parameswaran P. Critical evaluation of heat extraction temperature on soluble microbial products (SMP) and extracellular polymeric substances (EPS) quantification in wastewater processes. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2022; 85:2318-2331. [PMID: 35486457 DOI: 10.2166/wst.2022.089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
While soluble microbial products (SMP) and extracellular polymeric substances (EPS) in wastewater bioprocesses have been widely studied, a lack of standard quantification procedures make it difficult to compare results between studies. This study investigated the effect of temperature on SMP and EPS profiles for biological nutrient removal (BNR) sludges and aerobic membrane bioreactor sludge by adapting the commonly used heat extraction and centrifugation scheme, followed by colorimetric quantification of the carbohydrate and protein fractions using the phenol-sulfuric acid (PS) and the bicinchoninic acid (BCA) methods, respectively. To overcome known inconsistencies in colorimetry, total carbon (TC), total nitrogen (TN), and fluorometry analyses were performed in tandem. SMP samples marginally benefitted from heat extraction, owing to their mostly soluble nature, while EPS profiles were greatly influenced by temperature. 60 °C appears to be a suitable general-purpose extraction temperature near the lysis threshold for the sludges tested. The PS method's misestimation due to lack of specificity was observed and contrasted by TC analyses, while the TN analyses corroborated the BCA assays. Fluorometry proved to be a sensitive and rapid analytical method that provided semi-quantitative information on SMP and EPS constituents, particularly its proteinaceous components, with positive implications for robust wastewater process control.
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Affiliation(s)
- Kahao Lim
- Department of Civil Engineering, Kansas State University, 2118 Fiedler Hall, 1701C Platt St., Manhattan, KS 66506, USA E-mail:
| | - Prathap Parameswaran
- Department of Civil Engineering, Kansas State University, 2118 Fiedler Hall, 1701C Platt St., Manhattan, KS 66506, USA E-mail:
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12
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Cheng G, Ding H, Chen G, Shi H, Zhang X, Zhu M, Tan W. Effects of cadmium sulfide nanoparticles on sulfate bioreduction and oxidative stress in Desulfovibrio desulfuricans. BIORESOUR BIOPROCESS 2022; 9:35. [PMID: 38647594 PMCID: PMC10991916 DOI: 10.1186/s40643-022-00523-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 03/10/2022] [Indexed: 11/10/2022] Open
Abstract
Sulfate-containing wastewater has a serious threat to the environment and human health. Microbial technology has great potential for the treatment of sulfate-containing wastewater. It was found that nano-photocatalysts could be used as extracellular electron donors to promote the growth and metabolic activity of non-photosynthetic microorganisms. However, nano-photocatalysts could also induce oxidative stress and damage cells. Therefore, the interaction mechanism between photosynthetic nanocatalysts and non-photosynthetic microorganisms is crucial to determine the regulatory strategies for microbial wastewater treatment technologies. In this paper, the mechanism and regulation strategy of cadmium sulfide nanoparticles (CdS NPs) on the growth of sulfate-reducing bacteria and the sulfate reduction process were investigated. The results showed that the sulfate reduction efficiency could be increased by 6.4% through CdS NPs under light conditions. However, the growth of Desulfovibrio desulfuricans C09 was seriously inhibited by 55% due to the oxidative stress induced by CdS NPs on cells. The biomass and sulfate reduction efficiency could be enhanced by 6.8% and 5.9%, respectively, through external addition of humic acid (HA). At the same time, the mechanism of the CdS NPs strengthening the sulfate reduction process by sulfate bacteria was also studied which can provide important theoretical guidance and technical support for the development of microbial technology combined with extracellular electron transfer (EET) for the treatment of sulfate-containing wastewater.
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Affiliation(s)
- Guoqing Cheng
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, China
| | - Huili Ding
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, China
| | - Guanglin Chen
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, China
| | - Hongjie Shi
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, China
| | - Xu Zhang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, China.
| | - Minglong Zhu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, China
| | - Wensong Tan
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, China
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13
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Song Y, Ma F, Sun M, Mu G, Tuo Y. The Chemical Structure Properties and Promoting Biofilm Activity of Exopolysaccharide Produced by Shigella flexneri. Front Microbiol 2022; 12:807397. [PMID: 35185832 PMCID: PMC8854994 DOI: 10.3389/fmicb.2021.807397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 12/23/2021] [Indexed: 11/17/2022] Open
Abstract
Shigella flexneri is a waterborne and foodborne pathogen that can damage human health. The exopolysaccharides (S-EPS) produced by S. flexneri CMCC51574 were found to promote biofilm formation and virulence. In this research, the crude S-EPS produced by S. flexneri CMCC51574 were separated into three main different fractions, S-EPS 1-1, S-EPS 2-1, and S-EPS 3-1. The structure of the S-ESP 2-1 was identified by FT-IR, ion chromatography analysis, methylation analysis, and NMR analysis. The main chain of S-EPS 2-1 was α-Manp-(1 → 3)-α-Manp-[(1 → 2,6)-α-Manp]15-[(1 → 2)-Manf-(1→]8; there were two branched-chain R1 and R2 with a ratio of 4:1, R1: α-Manp-(1 → 6)- and R2: α-Manp-(1 → 6)- Glc-(1 → 6)- were linked with (1 → 2,6)-α-Manp. It was found that S-EPS 2-1 exhibited the highest promoting effect on biofilm formation of S. flexneri. The S-EPS 2-1 was identified to interact with extracellular DNA (eDNA) of S. flexneri, indicating that the S-EPS 2-1 was the specific polysaccharide in the spatial structure of biofilm formation. Our research found the important role of S-EPS in S. flexneri biofilm formation, which will help us to understand the underlining mechanisms of the biofilm formation and find effective ways to prevent S. flexneri biofilm infection.
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Affiliation(s)
- Yinglong Song
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China
| | - Fenglian Ma
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China
| | - Mengying Sun
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China
| | - Guangqing Mu
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China
- Dalian Probiotics Function Research Key Laboratory, Dalian Polytechnic University, Dalian, China
| | - Yanfeng Tuo
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China
- *Correspondence: Yanfeng Tuo,
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14
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Wang X, Chen T, Gao C, Xie Y, Zhang A. Use of extracellular polymeric substances as natural redox mediators to enhance denitrification performance by accelerating electron transfer and carbon source metabolism. BIORESOURCE TECHNOLOGY 2022; 345:126522. [PMID: 34896536 DOI: 10.1016/j.biortech.2021.126522] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 12/02/2021] [Accepted: 12/03/2021] [Indexed: 06/14/2023]
Abstract
Extracellular polymeric substances (EPS) extracted from waste activated sludge were used as endogenous redox mediator to enhance denitrification performance. The nitrate reduction rate increased 1.42-fold when EPS were added at 75 mg C/L (C represents total organic carbon). EPS addition decreased the charge transfer resistance and improved the electron transport system activity. The nitrate reductase and nitrite reductase activities improved by 29.7% and 25.4%, respectively. The activation energy of the system with EPS addition (25.82 kJ/mol) was 31.1% lower than that of the control group (37.49 kJ/mol). Besides, EPS could be used as electron carriers to accelerate electron transport; its primary role was similar to that of the quinone loop in the electron transfer chain. More importantly, EPS addition enhanced carbon source metabolism, which increased the available nicotinamide adenine dinucleotide yield to 1.21 times that of the control group, and thus promoted the denitrification performance of activated sludge.
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Affiliation(s)
- Xianbao Wang
- School of Environmental Science and Engineering, Shaanxi University of Science and Technology, Xi'an, Shaanxi Province 710021, China; China Light Industry Water Pollution Control Engineering Center, Xi'an, Shaanxi Province 710021, China.
| | - Tiantian Chen
- School of Environmental Science and Engineering, Shaanxi University of Science and Technology, Xi'an, Shaanxi Province 710021, China
| | - Chuyue Gao
- School of Environmental Science and Engineering, Shaanxi University of Science and Technology, Xi'an, Shaanxi Province 710021, China
| | - Yili Xie
- School of Environmental Science and Engineering, Shaanxi University of Science and Technology, Xi'an, Shaanxi Province 710021, China
| | - Anlong Zhang
- School of Environmental Science and Engineering, Shaanxi University of Science and Technology, Xi'an, Shaanxi Province 710021, China; China Light Industry Water Pollution Control Engineering Center, Xi'an, Shaanxi Province 710021, China
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15
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Wang H, Zheng Y, Zhu B, Zhao F. In situ role of extracellular polymeric substances in microbial electron transfer by Methylomonas sp. LW13. FUNDAMENTAL RESEARCH 2021. [DOI: 10.1016/j.fmre.2021.07.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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16
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Wang ZY, Ju CJ, Zhang R, Hua JQ, Chen RP, Liu GX, Yin K, Yu L. Acceleration of the bio-reduction of methyl orange by a magnetic and extracellular polymeric substance nanocomposite. JOURNAL OF HAZARDOUS MATERIALS 2021; 420:126576. [PMID: 34252658 DOI: 10.1016/j.jhazmat.2021.126576] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 07/01/2021] [Accepted: 07/02/2021] [Indexed: 06/13/2023]
Abstract
Extracellular electron transfer (EET) plays an important role in bio-reduction of environmental pollutants. Extracellular polymeric substances (EPS), a kind of biogenic macromolecule, contain functional groups responsible for acceleration of EET. In this study, azo dye-methyl orange (MO) was chosen as a model pollutant, and a Fe3O4 and EPS nanocomposite (Fe3O4@EPS) was prepared to evaluate its promotion on the bio-reduction of MO. The flower-like core-shell configuration of Fe3O4@EPS with a 12 nm of light layer of EPS was confirmed by TEM. The redox ability of EPS was well reserved on Fe3O4@EPS by FTIR and electrochemical test. The application of Fe3O4@EPS on sustained acceleration of MO decolorization were confirmed by batch experiments and anaerobic sequenced batch reactors. Due to biocompatibility of the biogenic shell, the as-prepared Fe3O4@EPS exhibited low toxic to microorganisms by the Live/dead cell test. Moreover, negligible leaching of EPS under high concentration of various anions and less than 10% of EPS was released under extreme acidic and basic pH condition. The results of study provided a new preparation method of biological intimate and environmentally friendly redox mediators and suggested a feasible way for its use on bio-reduction of pollutants.
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Affiliation(s)
- Zi-Yang Wang
- Department of Environmental Engineering, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China; School of Environmental Science, Nanjing XiaoZhuang University, Nanjing 211171, China
| | - Cheng-Jia Ju
- Department of Environmental Engineering, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China
| | - Rui Zhang
- Department of Environmental Engineering, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China
| | - Jing-Qiu Hua
- Department of Environmental Engineering, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China
| | - Rong-Ping Chen
- Department of Environmental Engineering, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China
| | - Guang-Xiang Liu
- School of Environmental Science, Nanjing XiaoZhuang University, Nanjing 211171, China
| | - Ke Yin
- Department of Environmental Engineering, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China
| | - Lei Yu
- Department of Environmental Engineering, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China; School of Environmental Science, Nanjing XiaoZhuang University, Nanjing 211171, China.
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17
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Li H, Cheng J, Dong H, Fang Z, Zhou J, Lin R. Zeolitic imidazolate framework-derived porous carbon enhances methanogenesis by facilitating interspecies electron transfer: Understanding fluorimetric and electrochemical responses of multi-layered extracellular polymeric substances. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 781:146447. [PMID: 33798894 DOI: 10.1016/j.scitotenv.2021.146447] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 03/08/2021] [Accepted: 03/09/2021] [Indexed: 06/12/2023]
Abstract
Modulating microbial electron transfer during anaerobic digestion can significantly improve syntrophic interactions for enhanced biogas production. As a carbonaceous conductive material, zeolite imidazolate framework-67 (ZIF-67)-derived porous carbon (PC) was hypothesized to act as a microbial electron transfer highway and assessed with respect to understanding the fluorimetric and electrochemical responses of multilayered extracellular polymeric substances (EPS). The highest biomethane yield (614.0 mL/g) from ethanol was achieved in the presence of 100 mg/L PC prepared at a carbonization temperature of 800 °C (PC-800), which was 28.2% higher than that without PC addition. Electrochemical analysis revealed that both the redox peak currents and conductivity of the methanogenic sludge increased, while the free charge transfer resistance decreased with PC-800 addition. The conductive PC-800 potentially functioned as an abiotic electron conduit to promote direct interspecies electron transfer, thereby resulting in decreased expression of functional genes associated with electrically conductive pili (e-pili) and hemeproteins. Additionally, PC-800 stimulated the secretion of redox-active humic substances (HSs), and excitation emission matrix spectra analysis indicated that the largest increase in percent fluorescence response of HSs occurred in the tightly bound EPS (TB-EPS) with addition of PC-800. This was attributed to the strong complexation ability of PC-800 particles to hydroxyl/carboxylic/phenolic moieties of HSs contained in the TB-EPS. Microbial analysis revealed that syntrophic/exoelectrogenic bacteria such as Pelotomaculum and Syntrophomonas, as well as hydrogenotrophic/electrotrophic methanogens such as Methanoculleus and Methanobacterium, were enriched in methanogenic sludge with adding PC-800. This study provided comprehensive insights for understanding the interactions among ZIF-derived PC, methanogenic microorganisms and their multilayered EPS.
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Affiliation(s)
- Hui Li
- State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China
| | - Jun Cheng
- State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China.
| | - Haiquan Dong
- State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China
| | - Zhe Fang
- State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China
| | - Junhu Zhou
- State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China
| | - Richen Lin
- MaREI Centre, Environmental Research Institute, University College Cork, Cork, Ireland; School of Engineering, University College Cork, Cork, Ireland
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18
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Zakaria BS, Dhar BR. Characterization and significance of extracellular polymeric substances, reactive oxygen species, and extracellular electron transfer in methanogenic biocathode. Sci Rep 2021; 11:7933. [PMID: 33846480 PMCID: PMC8041852 DOI: 10.1038/s41598-021-87118-w] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Accepted: 03/24/2021] [Indexed: 02/01/2023] Open
Abstract
The microbial electrolysis cell assisted anaerobic digestion holds great promises over conventional anaerobic digestion. This article reports an experimental investigation of extracellular polymeric substances (EPS), reactive oxygen species (ROS), and the expression of genes associated with extracellular electron transfer (EET) in methanogenic biocathodes. The MEC-AD systems were examined using two cathode materials: carbon fibers and stainless-steel mesh. A higher abundance of hydrogenotrophic Methanobacterium sp. and homoacetogenic Acetobacterium sp. appeared to play a major role in superior methanogenesis from stainless steel biocathode than carbon fibers. Moreover, the higher secretion of EPS accompanied by the lower ROS level in stainless steel biocathode indicated that higher EPS perhaps protected cells from harsh metabolic conditions (possibly unfavorable local pH) induced by faster catalysis of hydrogen evolution reaction. In contrast, EET-associated gene expression patterns were comparable in both biocathodes. Thus, these results indicated hydrogenotrophic methanogenesis is the key mechanism, while cathodic EET has a trivial role in distinguishing performances between two cathode electrodes. These results provide new insights into the efficient methanogenic biocathode development.
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Affiliation(s)
- Basem S. Zakaria
- grid.17089.37Civil and Environmental Engineering, University of Alberta, 9211-116 Street NW, Edmonton, AB T6G 1H9 Canada
| | - Bipro Ranjan Dhar
- grid.17089.37Civil and Environmental Engineering, University of Alberta, 9211-116 Street NW, Edmonton, AB T6G 1H9 Canada
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19
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You LX, Zhang RR, Dai JX, Lin ZT, Li YP, Herzberg M, Zhang JL, Al-Wathnani H, Zhang CK, Feng RW, Liu H, Rensing C. Potential of cadmium resistant Burkholderia contaminans strain ZCC in promoting growth of soy beans in the presence of cadmium. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 211:111914. [PMID: 33454593 DOI: 10.1016/j.ecoenv.2021.111914] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 12/28/2020] [Accepted: 01/05/2021] [Indexed: 06/12/2023]
Abstract
Bioremediation of Cd contaminated environments can be assisted by plant-growth-promoting bacteria (PGPB) enabling plant growth in these sites. Here a gram-negative Burkholderia contaminans ZCC was isolated from mining soil at a copper-gold mine. When exposed to Cd(II), ZCC displayed high Cd resistance and the minimal inhibitory concentration was 7 mM in LB medium. Complete genome analysis uncovered B. contaminans ZCC contained 3 chromosomes and 2 plasmids. One of these plasmids was shown to contain a multitude of heavy metal resistance determinants including genes encoding a putative Cd-translocating PIB-type ATPase and an RND-type related to the Czc-system. These additional heavy metal resistance determinants are likely responsible for the increased resistance to Cd(II) and other heavy metals in comparison to other strains of B. contaminans. B. contaminans ZCC also displayed PGPB traits such as 1-aminocyclopropane-1-carboxylate deaminase activity, siderophore production, organic and inorganic phosphate solubilization and indole acetic acid production. Moreover, the properties and Cd(II) binding characteristics of extracellular polymeric substances was investigated. ZCC was able to induce extracellular polymeric substances production in response to Cd and was shown to be chemically coordinated to Cd(II). It could promote the growth of soybean in the presence of elevated concentrations of Cd(II). This work will help to better understand processes important in bioremediation of Cd-contaminated environment.
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Affiliation(s)
- Le-Xing You
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China
| | - Rui-Rui Zhang
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China
| | - Jia-Xin Dai
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China
| | - Zi-Ting Lin
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China
| | - Yuan-Ping Li
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China
| | - Martin Herzberg
- Molecular Microbiology, Institute for Biology/Microbiology, Martin-Luther-University Halle-Wittenberg, Kurt-Mothes-Str. 3, Halle/Saale 06120, Germany
| | - Jin-Lin Zhang
- State Key Laboratory of Grassland Agro-ecosystems, College of Pastoral Agriculture, Science and Technology, Lanzhou University, Lanzhou 730000, PR China
| | - Hend Al-Wathnani
- Department of Botany and Microbiology, King Saud University, Riyadh, Saudi Arabia
| | - Cheng-Kang Zhang
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China; College of Life Sciences, Ningde Normal University, Ningde 352100, PR China
| | - Ren-Wei Feng
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China
| | - Hong Liu
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China.
| | - Christoper Rensing
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China.
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20
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Song Y, Sun M, Feng L, Liang X, Song X, Mu G, Tuo Y, Jiang S, Qian F. Antibiofilm Activity of Lactobacillus plantarum 12 Exopolysaccharides against Shigella flexneri. Appl Environ Microbiol 2020; 86:e00694-20. [PMID: 32444475 PMCID: PMC7376565 DOI: 10.1128/aem.00694-20] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Accepted: 05/14/2020] [Indexed: 12/13/2022] Open
Abstract
In developing countries, Shigella flexneri is the most common enteric pathogen causing bacillary dysentery. Biofilm formation by S. flexneri can cause the emergence of antibiotic-resistant strains, which poses serious threats to food safety and human health. In this study, the effects of Lactobacillus plantarum 12 exopolysaccharides (L-EPSs) and S. flexneri exopolysaccharides (S-EPSs) on S. flexneri CMCC51574 biofilm formation were investigated. The results showed that L-EPS could decrease polysaccharide production in the extracellular polymeric matrix of S. flexneri and inhibit biofilm formation by S. flexneri L-EPS could decrease the minimum biofilm elimination concentration (MBEC) of antibiotics against S. flexneri biofilm and inhibit S. flexneri adhesion to and invasion into HT-29 cell monolayers, which might be ascribed to S. flexneri biofilm disturbance by L-EPS. In contrast, S-EPS exhibited the opposite effects compared to L-EPS. The monosaccharide composition analysis showed that L-EPS was composed of mannose, glucuronic acid, galactosamine, glucose, galactose, and xylose, with the molar ratio of 32.26:0.99:1.79:5.63:0.05:4.07, while S-EPS was composed of mannose, glucuronic acid, galactosamine, glucose, and galactose, with the molar ratio of 25.43:2.28:7.13:5.35. L-EPS was separated into the neutral polysaccharide L-EPS 1-1 and the acidic polysaccharide L-EPS 2-1 by ion-exchange chromatography and gel chromatography. L-EPS 2-1 exerted higher antibiofilm activity than L-EPS 1-1. The antibiofilm activity of L-EPS might be associated with its structure.IMPORTANCES. flexneri is a widespread foodborne pathogen causing food contamination and responsible for food poisoning outbreaks related to various foods in developing countries. Not only has biofilm formation by S. flexneri been difficult to eliminate, but it has also increased the drug resistance of the strain. In the present study, it was demonstrated that L-EPSs secreted by Lactobacillus plantrum 12 could inhibit S. flexneri biofilm formation on, adhesion to, and invasion into HT-29 cells. Also, L-EPSs could decrease the minimum biofilm elimination concentration (MBEC) of the antibiotics used against S. flexneri biofilm. Therefore, L-EPSs were shown to be bioactive macromolecules with the potential ability to act against S. flexneri infections.
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Affiliation(s)
- Yinglong Song
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, People's Republic of China
| | - Mengying Sun
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, People's Republic of China
| | - Lu Feng
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, People's Republic of China
| | - Xue Liang
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, People's Republic of China
| | - Xing Song
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, People's Republic of China
| | - Guangqing Mu
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, People's Republic of China
- Dalian Probiotics Function Research Key Laboratory, Dalian Polytechnic University, Dalian, People's Republic of China
| | - Yanfeng Tuo
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, People's Republic of China
| | - Shujuan Jiang
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, People's Republic of China
| | - Fang Qian
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, People's Republic of China
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21
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Yan J, Liu J, Ye W, Yuan W, Lin J, Xie J, Huang X, Xie J, Bao M, Yang J, Liu S, Chen W, Chen Y, Zhang H. Enhanced organic compounds utilization and desalination of coal-fired power plant FGD wastewater by mixed bacterial sulphate reducing consortium. Biochem Eng J 2020. [DOI: 10.1016/j.bej.2020.107549] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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22
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Yan J, Ye W, Liang X, Wang S, Xie J, Zhong K, Bao M, Yang J, Wen H, Li S, Chen Y, Gu JD, Zhang H. Enhanced reduction of sulfate and chromium under sulfate-reducing condition by synergism between extracellular polymeric substances and graphene oxide. ENVIRONMENTAL RESEARCH 2020; 183:109157. [PMID: 32006768 DOI: 10.1016/j.envres.2020.109157] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 01/17/2020] [Accepted: 01/20/2020] [Indexed: 06/10/2023]
Abstract
Microbial reduction of sulfate and metal were simultaneously enhanced in the presence of graphene oxide (GO)-like nanomaterials, however, the mechanism remained unclear. In this study, bio-reduction of Cr was compared between free-living bacterium BY7 and immobilized BY7 (BY-rGO) on reduced GO particles. The role of extracellular polymeric substances (EPS) and rGO material on reduction of sulfate and Cr was investigated. Cr(VI) was reduced to Cr(III) and elemental Cr by BY-rGO particles up to 51% and 28%, respectively. EPS produced by the bacterium BY7 mainly consisted of proteins, polysaccharides, nucleic acids and humic substances. Concentration of EPS was sharply increased (about 54%) with the addition of graphene oxide, while the composition of EPS components was strongly affected by the exposure to Cr. By removing surface EPS without breaking the cells, reduction activities of sulfate and chromium by both BY-rGO particles and free-living BY7 cells were decreased. In contrast, reduction of sulfate and Cr by the free-living BY7 cells was enhanced with external addition of extracted EPS. Based on electrochemical analysis, the reduction peak indicating enhanced electron transfer was lost after removing EPS. Moreover, the contribution of each EPS fractions on sulfate and Cr reduction followed an order of polysaccharides > proteins > humic substances. Therefore, microbial sulfate and Cr reduction processes in the presence of BY-rGO particles were enhanced by the increasing amounts of EPS, which likely mediated electron transfer during sulfate and Cr reduction, and relieved bacteria from metal toxicity. Nevertheless, the presence of rGO was crucially important for elemental Cr production under sulfate-reducing condition, which might contribute to lowering electric potential or reducing activation energy for Cr(III) reduction. This work provided direct evidences for enhancing sulfate and Cr reduction activities by supplement of EPS as an additive to increase treatment efficiency in environmental bioremediation.
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Affiliation(s)
- Jia Yan
- School of Environmental Science and Engineering, Guangzhou University, Guangzhou, 510006, PR China; Guangdong Provincial Key Laboratory of Radionuclides Pollution Control and Resources, Guangzhou, 510006, PR China; Guangzhou University-Linköping University Research Center on Urban Sustainable Development, Guangzhou University, 510006, Guangzhou, PR China.
| | - Weizhuo Ye
- School of Environmental Science and Engineering, Guangzhou University, Guangzhou, 510006, PR China
| | - Xiaoshan Liang
- School of Environmental Science and Engineering, Guangzhou University, Guangzhou, 510006, PR China
| | - Siji Wang
- School of Environmental Science and Engineering, Guangzhou University, Guangzhou, 510006, PR China
| | - Jiehui Xie
- School of Environmental Science and Engineering, Guangzhou University, Guangzhou, 510006, PR China
| | - Kengqiang Zhong
- School of Environmental Science and Engineering, Guangzhou University, Guangzhou, 510006, PR China
| | - Min Bao
- School of Environmental Science and Engineering, Guangzhou University, Guangzhou, 510006, PR China
| | - Jinbin Yang
- School of Environmental Science and Engineering, Guangzhou University, Guangzhou, 510006, PR China
| | - Huijun Wen
- School of Environmental Science and Engineering, Guangzhou University, Guangzhou, 510006, PR China
| | - Shugeng Li
- School of Environmental Science and Engineering, Guangzhou University, Guangzhou, 510006, PR China
| | - Yongheng Chen
- School of Environmental Science and Engineering, Guangzhou University, Guangzhou, 510006, PR China
| | - Ji-Dong Gu
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Hongguo Zhang
- School of Environmental Science and Engineering, Guangzhou University, Guangzhou, 510006, PR China; Guangdong Provincial Key Laboratory of Radionuclides Pollution Control and Resources, Guangzhou, 510006, PR China; Guangzhou University-Linköping University Research Center on Urban Sustainable Development, Guangzhou University, 510006, Guangzhou, PR China.
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Yang G, Lin J, Zeng EY, Zhuang L. Extraction and characterization of stratified extracellular polymeric substances in Geobacter biofilms. BIORESOURCE TECHNOLOGY 2019; 276:119-126. [PMID: 30616210 DOI: 10.1016/j.biortech.2018.12.100] [Citation(s) in RCA: 74] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 12/25/2018] [Accepted: 12/26/2018] [Indexed: 06/09/2023]
Abstract
Extracellular polymeric substances (EPS) play crucial roles in promoting biofilm formation and contribute to electrochemical activities of biofilms in bioelectrochemical systems (BES). In this study, three stratified EPS fractions were extracted from Geobacter biofilms using EDTA-, ultrasound- and heating-based protocols and characterized with chemical, spectral and electrochemical analyses. Results suggested that, for Geobacter biofilms, ultrasound-based extraction protocol was more effective in EPS yield (62.1-66.5 mg C/g dry cell) than EDTA method, and had less cell lysis than heating method. The extraction methods greatly affected the proteins composition in the extracted EPS, indicated by the varied ratios of tryptophan/tyrosine protein-like substances. Electrochemical measurements demonstrated a good correlation between protein concentration and extracellular electron transfer function for both tightly-bound EPS and total EPS. This is the first study to extract and characterize stratified EPS fractions from Geobacter biofilms, and helpful for better understanding the function of EPS in BESs predominated by Geobacter.
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Affiliation(s)
- Guiqin Yang
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China
| | - Jun Lin
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China
| | - Eddy Y Zeng
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China
| | - Li Zhuang
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China.
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24
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Nookongbut P, Kantachote D, Megharaj M, Naidu R. Reduction in arsenic toxicity and uptake in rice (Oryza sativa L.) by As-resistant purple nonsulfur bacteria. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:36530-36544. [PMID: 30374717 DOI: 10.1007/s11356-018-3568-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Accepted: 10/22/2018] [Indexed: 06/08/2023]
Abstract
This study aimed to investigate the potential of Rhodopseudomonas palustris C1 and Rubrivivax benzoatilyticus C31 to ameliorate As toxicity and to reduce As uptake in rice. Strain C1 was superior to strain C31 for siderophore production. The mixed culture (1: 1) was most effective in reducing the toxicity of As species [As(III) and/or As(V), each 30 mg/l] by yielding maximal germination index that related to α- and β-amylase activities in two Thai rice cultivars (HomNil: HN and PathumThani 1: PT). Arsenic toxicity to the seed germination followed the order: mixed As species > As(III) > As(V); and the toxicity was reduced in inoculated sets, particularly with a mixed culture. The mixed culture significantly enhanced rice growth under As stress in both rice cultivars as indicated by an increase in the production of chlorophyll a and b, and also supporting the non-enzymatic (carotenoids, lipid oxidation, and nitric oxide) and enzymatic (superoxide dismutase, ascorbate peroxidase, catalase, and glutathione reductase) activities. These were concomitant with productions of 5-aminolevulinic acid, indole-3-acetic acid, exopolymeric substances, and siderophores which significantly reduced As accumulation in treated rice. It can be concluded that the mixed culture has great potential to ameliorate rice from As toxicity by preventing As species entry into rice for enhancing rice growth and also for reducing As accumulation to produce safe rice from rice grown in contaminated paddy fields.
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Affiliation(s)
- Phitthaya Nookongbut
- Department of Microbiology, Faculty of Science, Prince of Songkla University, Hat Yai, 90112, Thailand
| | - Duangporn Kantachote
- Department of Microbiology, Faculty of Science, Prince of Songkla University, Hat Yai, 90112, Thailand.
- Center of Excellence on Hazardous Substance Management (HSM), Bangkok, 10330, Thailand.
| | - Mallavarapu Megharaj
- Global Centre for Environmental Remediation, Faculty of Science, The University of Newcastle, Callaghan, NSW, 2308, Australia
- Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC-CARE), The University of Newcastle, Callaghan, NSW, 2308, Australia
| | - Ravi Naidu
- Global Centre for Environmental Remediation, Faculty of Science, The University of Newcastle, Callaghan, NSW, 2308, Australia
- Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC-CARE), The University of Newcastle, Callaghan, NSW, 2308, Australia
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25
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Xiao Y, Zhang E, Zhang J, Dai Y, Yang Z, Christensen HEM, Ulstrup J, Zhao F. Extracellular polymeric substances are transient media for microbial extracellular electron transfer. SCIENCE ADVANCES 2017; 3:e1700623. [PMID: 28695213 PMCID: PMC5498105 DOI: 10.1126/sciadv.1700623] [Citation(s) in RCA: 312] [Impact Index Per Article: 44.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Accepted: 05/18/2017] [Indexed: 05/19/2023]
Abstract
Microorganisms exploit extracellular electron transfer (EET) in growth and information exchange with external environments or with other cells. Every microbial cell is surrounded by extracellular polymeric substances (EPS). Understanding the roles of three-dimensional (3D) EPS in EET is essential in microbiology and microbial exploitation for mineral bio-respiration, pollutant conversion, and bioenergy production. We have addressed these challenges by comparing pure and EPS-depleted samples of three representative electrochemically active strains viz Gram-negative Shewanella oneidensis MR-1, Gram-positive Bacillus sp. WS-XY1, and yeast Pichia stipites using technology from electrochemistry, spectroscopy, atomic force microscopy, and microbiology. Voltammetry discloses redox signals from cytochromes and flavins in intact MR-1 cells, whereas stronger signals from cytochromes and additional signals from both flavins and cytochromes are found after EPS depletion. Flow cytometry and fluorescence microscopy substantiated by N-acetylglucosamine and electron transport system activity data showed less than 1.5% cell damage after EPS extraction. The electrochemical differences between normal and EPS-depleted cells therefore originate from electrochemical species in cell walls and EPS. The 35 ± 15-nm MR-1 EPS layer is also electrochemically active itself, with cytochrome electron transfer rate constants of 0.026 and 0.056 s-1 for intact MR-1 and EPS-depleted cells, respectively. This surprisingly small rate difference suggests that molecular redox species at the core of EPS assist EET. The combination of all the data with electron transfer analysis suggests that electron "hopping" is the most likely molecular mechanism for electrochemical electron transfer through EPS.
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Affiliation(s)
- Yong Xiao
- CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- Department of Chemistry, Technical University of Denmark, Kgs. Lyngby 2800, Denmark
| | - Enhua Zhang
- CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- Key Laboratory of Environmental Biology and Pollution Control, College of Environmental Science and Engineering, Hunan University, Changsha 410082, China
| | - Jingdong Zhang
- Department of Chemistry, Technical University of Denmark, Kgs. Lyngby 2800, Denmark
| | - Youfen Dai
- CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Zhaohui Yang
- Key Laboratory of Environmental Biology and Pollution Control, College of Environmental Science and Engineering, Hunan University, Changsha 410082, China
| | | | - Jens Ulstrup
- Department of Chemistry, Technical University of Denmark, Kgs. Lyngby 2800, Denmark
| | - Feng Zhao
- CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
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