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Zhang S, Huang X, Dong W, Wang H, Hu L, Zhou G, Zheng Z. Potential effects of Cu 2+ stress on nitrogen removal performance, microbial characteristics, and metabolism pathways of biofilm reactor. ENVIRONMENTAL RESEARCH 2024; 259:119541. [PMID: 38960353 DOI: 10.1016/j.envres.2024.119541] [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: 03/13/2024] [Revised: 06/20/2024] [Accepted: 07/01/2024] [Indexed: 07/05/2024]
Abstract
Sequencing batch biofilm reactors (SBBR) were utilized to investigate the impact of Cu2+ on nitrogen (N) removal and microbial characteristics. The result indicated that the low concentration of Cu2+ (0.5 mg L-1) facilitated the removal of ammonia nitrogen (NH4+-N), total nitrogen (TN), nitrate nitrogen (NO3--N), and chemical oxygen demand (COD). In comparison to the average effluent concentration of the control group, the average effluent concentrations of NH4+-N, NO3--N, COD, and TN were found to decrease by 40.53%, 17.02%, 10.73%, and 15.86%, respectively. Conversely, the high concentration of Cu2+ (5 mg L-1) resulted in an increase of 94.27%, 55.47%, 22.22%, and 14.23% in the aforementioned parameters, compared to the control group. Low concentrations of Cu2+ increased the abundance of nitrifying bacteria (Rhodanobacter, unclassified-o-Sacharimonadales), denitrifying bacteria (Thermomonas, Comamonas), denitrification-associated genes (hao, nosZ, norC, nffA, nirB, nick, and nifD), and heavy-metal-resistant genes related to Cu2+ (pcoB, cutM, cutC, pcoA, copZ) to promote nitrification and denitrification. Conversely, high concentration Cu2+ hindered the interspecies relationship among denitrifying bacteria genera, nitrifying bacteria genera, and other genera, reducing denitrification and nitrification efficiency. Cu2+ involved in the N and tricarboxylic acid (TCA) cycles, as evidenced by changes in the abundance of key enzymes, such as (EC:1.7.99.1), (EC:1.7.2.4), and (EC:1.1.1.42), which initially increased and then decreased with varying concentrations of Cu2+. Conversely, the abundance of EC1.7.2.1, associated with the accumulation of nitrite nitrogen (NO2--N), gradually declined. These findings provided insights into the impact of Cu2+ on biological N removal.
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Affiliation(s)
- Shuai Zhang
- Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, School of Environmental Science and Engineering, Nanjing University of Information Science & Technology, Nanjing, 210044, China
| | - Xiao Huang
- Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, School of Environmental Science and Engineering, Nanjing University of Information Science & Technology, Nanjing, 210044, China; Shenzhen Key Laboratory of Water Resource Utilization and Environmental Pollution Control, School of Civil and Environmental Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen, 518055, China.
| | - Wenyi Dong
- Shenzhen Key Laboratory of Water Resource Utilization and Environmental Pollution Control, School of Civil and Environmental Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen, 518055, China; State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Hongjie Wang
- Shenzhen Key Laboratory of Water Resource Utilization and Environmental Pollution Control, School of Civil and Environmental Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen, 518055, China; State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Liangshan Hu
- Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, School of Environmental Science and Engineering, Nanjing University of Information Science & Technology, Nanjing, 210044, China
| | - Guorun Zhou
- Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, School of Environmental Science and Engineering, Nanjing University of Information Science & Technology, Nanjing, 210044, China
| | - Zhihao Zheng
- Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, School of Environmental Science and Engineering, Nanjing University of Information Science & Technology, Nanjing, 210044, China
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Wang X, Guo N, Zhang Y, Wang G, Shi K. Cross-protection and cross-feeding between Enterobacter and Comamonas promoting their coexistence and cadmium tolerance in Oryza sativa L. Microbiol Res 2024; 286:127806. [PMID: 38924817 DOI: 10.1016/j.micres.2024.127806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2024] [Revised: 04/13/2024] [Accepted: 06/06/2024] [Indexed: 06/28/2024]
Abstract
Metabolic cross-feeding is a pervasive interaction between bacteria to acquire novel phenotypes. However, our current understanding of the survival mechanism for cross-feeding in cocultured bacterial biofilms under heavy-metal conditions remains limited. Herein, we found that Comamonas sp. A23 produces L-phenylalanine to activate the L-phenylalanine degradation pathway in Enterobacter sp. A11, enhancing biofilm formation and cadmium [Cd(II)] immobilization in A11. The genes responsible for L-phenylalanine-degradation (paaK) and cell attachment and aggregation (csgAD) are essential for biofilm formation and Cd(II) immobilization in A11 induced by L-phenylalanine. The augmentation of A11 biofilms, in turn, protects A23 under Cd(II) and H2O2 stresses. The plant-based experiments demonstrate that the induction of two rice Cd(II) transporters, OsCOPT4 and OsBCP1, by A11 and A23 enhances rice resistance against Cd(II) and H2O2 stresses. Overall, our findings unveil the mutual dependence between bacteria and rice on L-phenylalanine cross-feeding for survival under abiotic stress.
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Affiliation(s)
- Xing Wang
- National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Naijiang Guo
- National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Yao Zhang
- National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Gejiao Wang
- National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Kaixiang Shi
- National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, PR China.
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Li Y, Cheng L, Yang B, Ding Y, Zhao Y, Wu Y, Nie Y, Liu Y, Xu A. Zinc oxide/graphene oxide nanocomposites specifically remediated Cd-contaminated soil via reduction of bioavailability and ecotoxicity of Cd. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 940:173641. [PMID: 38825205 DOI: 10.1016/j.scitotenv.2024.173641] [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: 01/19/2024] [Revised: 03/22/2024] [Accepted: 05/28/2024] [Indexed: 06/04/2024]
Abstract
From both environment and health perspectives, sustainable management of ever-growing soil contamination by heavy metal is posing a serious global concern. The potential ecotoxicity of cadmium (Cd) to soil and ecosystem seriously threatens human health. Developing efficient, specific, and long-term remediation technology for Cd-contaminated soil is impending to synchronously minimize the bioavailability and ecotoxicity of Cd. In the present study, zinc oxide/graphene oxide nanocomposite (ZnO/GO) was developed as a novel amendment for remediating Cd-contaminated soil. Our results showed that ZnO/GO effectively decreased the available soil Cd content, and increased pH and cation exchange capacity (CEC) in both Cd-spiked standard soil and Cd-contaminated mine field soil through the interaction between ZnO/GO and soil organic acids. Using Caenorhabditis elegans (C. elegans) as a model organism for soil safety evaluation, ZnO/GO was further proved to decrease the ecotoxicity of Cd-contaminated soil. Specifically, ZnO/GO promoted Cd excretion and declined Cd storage in C. elegans by increasing the expression of gene ttm-1 and decreasing the level of gene cdf-2, which were responsible for Cd transportation and Cd accumulation, respectively. Moreover, the efficacy of ZnO/GO in remediating the properties and ecotoxicity of Cd-contaminated soil increased gradually with the time gradient, and could maintain a long-term effect after reaching the optimal remediation efficiency. Our findings established a specific and long-term strategy to simultaneously improve soil properties and reduce ecotoxicity of Cd-contaminated soil, which might provide new insights into the potential application of ZnO/GO in soil remediation for both ecosystem and human health.
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Affiliation(s)
- Yang Li
- School of Environmental Science and Optoelectronic Technology, University of Science and Technology of China, Hefei 230026, PR China; Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, CAS, High Magnetic Field Laboratory, Hefei Institutes of Physical Science, CAS, Hefei, Anhui, 230031, PR China
| | - Lei Cheng
- School of Environmental Science and Optoelectronic Technology, University of Science and Technology of China, Hefei 230026, PR China; Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, CAS, High Magnetic Field Laboratory, Hefei Institutes of Physical Science, CAS, Hefei, Anhui, 230031, PR China
| | - Baolin Yang
- School of Environmental Science and Optoelectronic Technology, University of Science and Technology of China, Hefei 230026, PR China; Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, CAS, High Magnetic Field Laboratory, Hefei Institutes of Physical Science, CAS, Hefei, Anhui, 230031, PR China
| | - Yuting Ding
- School of Environmental Science and Optoelectronic Technology, University of Science and Technology of China, Hefei 230026, PR China; Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, CAS, High Magnetic Field Laboratory, Hefei Institutes of Physical Science, CAS, Hefei, Anhui, 230031, PR China
| | - Yanan Zhao
- Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, CAS, High Magnetic Field Laboratory, Hefei Institutes of Physical Science, CAS, Hefei, Anhui, 230031, PR China
| | - Yuanyuan Wu
- School of Environmental Science and Optoelectronic Technology, University of Science and Technology of China, Hefei 230026, PR China; Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, CAS, High Magnetic Field Laboratory, Hefei Institutes of Physical Science, CAS, Hefei, Anhui, 230031, PR China
| | - Yaguang Nie
- Information Materials and Intelligent Sensing Laboratory of Anhui Province, Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, PR China
| | - Yun Liu
- Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, CAS, High Magnetic Field Laboratory, Hefei Institutes of Physical Science, CAS, Hefei, Anhui, 230031, PR China.
| | - An Xu
- School of Environmental Science and Optoelectronic Technology, University of Science and Technology of China, Hefei 230026, PR China; Anhui Province Key Laboratory of Environmental Toxicology and Pollution Control Technology, Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, CAS, High Magnetic Field Laboratory, Hefei Institutes of Physical Science, CAS, Hefei, Anhui, 230031, PR China; Information Materials and Intelligent Sensing Laboratory of Anhui Province, Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, PR China.
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An Q, Zheng N, Pan J, Ji Y, Wang S, Li X, Chen C, Peng L, Wang B. Association between plant microbiota and cadmium uptake under the influence of microplastics with different particle sizes. ENVIRONMENT INTERNATIONAL 2024; 190:108938. [PMID: 39111171 DOI: 10.1016/j.envint.2024.108938] [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: 06/12/2024] [Revised: 08/01/2024] [Accepted: 08/03/2024] [Indexed: 08/28/2024]
Abstract
Plant microbiota are an important factor impacting plant cadmium (Cd) uptake. However, little is known about how plant microbiota affects the Cd uptake by plants under the influence of microplastics (MPs) with different particle sizes. In this study, bacterial structure and assembly in the rhizosphere and endosphere in pakchoi were analyzed by amplicon sequencing of 16S rRNA genes under the influence of different particle sizes of polystyrene microplastics (PS-MPs) combined with Cd treatments. Results showed that there were no significant differences observed in the shoot endophytes among different treatments. However, compared to Cd treatment, larger-sized PS-MPs (2 and 20 μm) significantly increased community diversity and altered the structural composition of rhizosphere bacteria and root endophytes, while smaller-sized PS-MPs (0.2 μm) did not. Under the treatment of larger-sized PS-MPs, the niche breadth of rhizosphere bacteria and root endophytes were significantly increased. And larger-sized PS-MPs also maintained stability and complexity of bacterial co-occurrence networks, while smaller-sized PS-MPs reduced them. Furthermore, compared to Cd treatment, the addition of larger particle size PS-MPs decreased the proportion of homogeneous section, while increased the proportion of drift in root endophytic bacterial community assembly. The role of larger-sized MPs in the community assembly of rhizosphere bacteria was opposite. Using random forest and structural equation models, the study found that larger-sized PS-MPs can promote the colonization of specific bacterial taxa, such as Brevundimonas, AKAU4049, SWB02, Ellin6055, Porphyrobacter, Sphingorhabdus, Rhodobacter, Erythrobacter, Devosia and some other bacteria belonging to Alphaproteobacteria, in the rhizosphere and root endosphere. The colonization of these taxa can may induce the formation of biofilms in the roots, immobilize heavy metals through oxidation processes, and promote plant growth, thereby reducing Cd uptake by pakchoi. The findings of this study provide important insights into the microbial mechanisms underlying the influence of MPs with different particle sizes on plant Cd uptake.
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Affiliation(s)
- Qirui An
- Key Laboratory of Groundwater Resources and Environment of the Ministry of Education, College of New Energy and Environment, Jilin University, China
| | - Na Zheng
- Key Laboratory of Groundwater Resources and Environment of the Ministry of Education, College of New Energy and Environment, Jilin University, China.
| | - Jiamin Pan
- Northeast Institute of Geography and Agricultural Ecology, Chinese Academy of Sciences, Changchun, Jilin, China
| | - Yining Ji
- Key Laboratory of Groundwater Resources and Environment of the Ministry of Education, College of New Energy and Environment, Jilin University, China
| | - Sujing Wang
- Key Laboratory of Groundwater Resources and Environment of the Ministry of Education, College of New Energy and Environment, Jilin University, China
| | - Xiaoqian Li
- Key Laboratory of Groundwater Resources and Environment of the Ministry of Education, College of New Energy and Environment, Jilin University, China
| | - Changcheng Chen
- Key Laboratory of Groundwater Resources and Environment of the Ministry of Education, College of New Energy and Environment, Jilin University, China
| | - Liyuan Peng
- Key Laboratory of Groundwater Resources and Environment of the Ministry of Education, College of New Energy and Environment, Jilin University, China
| | - Bo Wang
- Key Laboratory of Groundwater Resources and Environment of the Ministry of Education, College of New Energy and Environment, Jilin University, China
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Wang X, Zhong L, Huo X, Guo N, Zhang Y, Wang G, Shi K. Chromate-induced methylglyoxal detoxification system drives cadmium and chromate immobilization by Cupriavidus sp. MP-37. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 343:123194. [PMID: 38145638 DOI: 10.1016/j.envpol.2023.123194] [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: 09/11/2023] [Revised: 12/01/2023] [Accepted: 12/17/2023] [Indexed: 12/27/2023]
Abstract
The detoxification of cadmium (Cd) or chromium (Cr) by microorganisms plays a vital role in bacterial survival and restoration of the polluted environment, but how microorganisms detoxify Cd and Cr simultaneously is largely unknown. Here, we isolated a bacterium, Cupriavidus sp. MP-37, which immobilized Cd(II) and reduced Cr(VI) simultaneously. Notably, strain MP-37 exhibited variable Cd(II) immobilization phenotypes, namely, cell adsorption and extracellular immobilization in the co-presence of Cd(II) and Cr(VI), while cell adsorption in the presence of Cd(II) alone. To unravel Cr(VI)-induced extracellular Cd(II) immobilization, proteomic analysis was performed, and methylglyoxal-scavenging protein (glyoxalase I, GlyI) and a regulator (YafY) showed the highest upregulation in the co-presence of Cd(II) and Cr(VI). GlyI overexpression reduced the intracellular methylglyoxal content and increased the immobilized Cd(II) content in extracellular secreta. The addition of lactate produced by GlyI protein with methylglyoxal as substrate increased the Cd(II) content in extracellular secreta. Reporter gene assay, electrophoretic mobility shift assay, and fluorescence quenching assay demonstrated that glyI expression was induced by Cr(VI) but not by Cd(II), and that YafY positively regulated glyI expression by binding Cr(VI). In the pot experiment, inoculation with the MP-37 strain reduced the Cd content of Oryza sativa L., and their secreted lactate reduced the Cr accumulation in Oryza sativa L. This study reveals that Cr(VI)-induced detoxification system drives methylglyoxal scavenging and Cd(II) extracellular detoxification in Cd(II) and Cr(VI) co-existence environment.
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Affiliation(s)
- Xing Wang
- National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Limin Zhong
- National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Xueqi Huo
- National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Naijiang Guo
- National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Yao Zhang
- National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Gejiao Wang
- National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Kaixiang Shi
- National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, PR China.
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Li Y, Narayanan M, Shi X, Chen X, Li Z, Ma Y. Biofilms formation in plant growth-promoting bacteria for alleviating agro-environmental stress. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 907:167774. [PMID: 37848152 DOI: 10.1016/j.scitotenv.2023.167774] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 10/02/2023] [Accepted: 10/10/2023] [Indexed: 10/19/2023]
Abstract
Biofilm formation represents a pivotal and adaptable trait among microorganisms within natural environments. This attribute plays a multifaceted role across diverse contexts, including environmental, aquatic, industrial, and medical systems. While previous research has primarily focused on the adverse impacts of biofilms, harnessing their potential effectively could confer substantial advantages to humanity. In the face of escalating environmental pressures (e.g., drought, salinity, extreme temperatures, and heavy metal pollution), which jeopardize global crop yields, enhancing crop stress tolerance becomes a paramount endeavor for restoring sufficient food production. Recently, biofilm-forming plant growth-promoting bacteria (PGPB) have emerged as promising candidates for agricultural application. These biofilms are evidence of microorganism colonization on plant roots. Their remarkable stress resilience empowers crops to thrive and yield even in harsh conditions. This is accomplished through increased root colonization, improved soil properties, and the synthesis of valuable secondary metabolites (e.g., ACC deaminase, acetin, 2,3-butanediol, proline, etc.). This article elucidates the mechanisms underpinning the role of biofilm-forming PGPB in bolstering plant growth amidst environmental challenges. Furthermore, it explores the tangible applications of these biofilms in agriculture and delves into strategies for manipulating biofilm formation to extract maximal benefits in practical crop production scenarios.
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Affiliation(s)
- Yujia Li
- College of Resources and Environment, Southwest University, Chongqing 400716, China
| | - Mathiyazhagan Narayanan
- Division of Research and Innovation, Department of Biotechnology, Saveetha School of Engineering, Saveetha Institute of Medical and Technical Science, Chennai 602105, Tamil Nadu, India
| | - Xiaojun Shi
- College of Resources and Environment, Southwest University, Chongqing 400716, China
| | - Xinping Chen
- College of Resources and Environment, Southwest University, Chongqing 400716, China
| | - Zhenlun Li
- College of Resources and Environment, Southwest University, Chongqing 400716, China
| | - Ying Ma
- College of Resources and Environment, Southwest University, Chongqing 400716, China.
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Zhao Z, Sun Y, Wang H, Yu Q. Regulation of cadmium-induced biofilm formation by artificial polysaccharide-binding proteins for enhanced phytoremediation. CHEMOSPHERE 2023; 342:140156. [PMID: 37714481 DOI: 10.1016/j.chemosphere.2023.140156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 08/28/2023] [Accepted: 09/11/2023] [Indexed: 09/17/2023]
Abstract
Phytoremediation is an economic way to attenuate soil heavy metal pollution, but is frequently limited by its low pollutant-removing efficiency. Recently, we revealed the close relation between polysaccharide-based biofilm formation and cadmium removal. In this study, for improving the phytoremediation efficiency, an artificial polysaccharide-binding protein was designed by synthetic biology techniques to regulate biofilm formation. The artificial protein Syn contained two polysaccharide-binding domains from the Ruminococcus flavefaciens CttA and the Clostridium cellulolyticum CipC, preferentially binding polysaccharides exposed on both cadmium-treated bacteria and plant roots. Under cadmium stress, Syn remarkably promoted bacterial polysaccharide production from 99 mg/L to 237 mg/L, leading to 1.23-fold higher biofilm biomass. During treatment of the remediation plants with exogenous cadmium-capturing bacteria, Syn improved root biofilm formation, with the root surface polysaccharide contents increasing by 79%, and the Log10 CFU/g root increasing from 7.01 to 7.80. Meanwhile, Syn remodeled the rhizosphere microbiome, especially increasing the abundance of the bacterial groups involved in biofilm formation and stress tolerance, e.g., Pseudomonas, Enterobacter, etc. Consequently, Syn promoted plant cadmium adsorption, with the cadmium-removing efficiency increasing from 17.2% to 33.8%. This study sheds light on synthetic biology-based regulation of biofilm formation for enhanced phytoremediation.
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Affiliation(s)
- Zirun Zhao
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin, 300071, PR China.
| | - Ying Sun
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin, 300071, PR China
| | - Hairong Wang
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin, 300071, PR China
| | - Qilin Yu
- Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, Department of Microbiology, College of Life Sciences, Nankai University, Tianjin, 300071, PR China.
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