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Huang ZS, Tan XQ, Yang HB, Zeng Y, Chen SJ, Wei ZS, Huang YQ. Mechanistic insights into tris(2-chloroisopropyl) phosphate biomineralization coupled with lead (II) biostabilization driven by denitrifying bacteria. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 945:173927. [PMID: 38901584 DOI: 10.1016/j.scitotenv.2024.173927] [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: 04/11/2024] [Revised: 05/24/2024] [Accepted: 06/09/2024] [Indexed: 06/22/2024]
Abstract
The ubiquity and persistence of organophosphate esters (OPEs) and heavy metal (HMs) pose global environmental risks. This study explored tris(2-chloroisopropyl)phosphate (TCPP) biomineralization coupled to lead (Pb2+) biostabilization driven by denitrifying bacteria (DNB). The domesticated DNB achieved synergistic bioremoval of TCPP and Pb2+ in the batch bioreactor (efficiency: 98 %).TCPP mineralized into PO43- and Cl-, and Pb2+ precipitated with PO43-. The TCPP-degrading/Pb2+-resistant DNB: Achromobacter, Pseudomonas, Citrobacter, and Stenotrophomonas, dominated the bacterial community, and synergized TCPP biomineralization and Pb2+ biostabilization. Metagenomics and metaproteomics revealed TCPP underwent dechlorination, hydrolysis, the TCA cycle-based dissimilation, and assimilation; Pb2+ was detoxified via bioprecipitation, bacterial membrane biosorption, EPS biocomplexation, and efflux out of cells. TCPP, as an initial donor, along with NO3-, as the terminal acceptor, formed a respiratory redox as the primary energy metabolism. Both TCPP and Pb2+ can stimulate phosphatase expression, which established the mutual enhancements between their bioconversions by catalyzing TCPP dephosphorylation and facilitating Pb2+ bioprecipitation. TCPP may alleviate the Pb2+-induced oxidative stress by aiding protein phosphorylation. 80 % of Pb2+ converted into crystalized pyromorphite. These results provide the mechanistic foundations and help develop greener strategies for synergistic bioremediation of OPEs and HMs.
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Affiliation(s)
- Zhen-Shan Huang
- School of Environment, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety, MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China
| | - Xiu-Qin Tan
- State Environmental Protection Key Laboratory of Water Environmental Simulation and Pollution Control, South China Institute of Environmental Sciences, MEE, Guangzhou 510530, China
| | - Han-Biao Yang
- School of Environment, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety, MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China
| | - Yuan Zeng
- School of Environment, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety, MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China
| | - She-Jun Chen
- School of Environment, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety, MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China.
| | - Zai-Shan Wei
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Guangzhou 510275, China
| | - Yu-Qi Huang
- School of Environment, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety, MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China
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Pal P, Pramanik K, Ghosh SK, Mondal S, Mondal T, Soren T, Maiti TK. Molecular and eco-physiological responses of soil-borne lead (Pb 2+)-resistant bacteria for bioremediation and plant growth promotion under lead stress. Microbiol Res 2024; 287:127831. [PMID: 39079267 DOI: 10.1016/j.micres.2024.127831] [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: 01/17/2024] [Revised: 06/25/2024] [Accepted: 07/01/2024] [Indexed: 08/22/2024]
Abstract
Lead (Pb) is the 2nd known portentous hazardous substance after arsenic (As). Being highly noxious, widespread, non-biodegradable, prolonged environmental presence, and increasing accumulation, particularly in arable land, Pb pollution has become a serious global health concern requiring urgent remediation. Soil-borne, indigenous microbes from Pb-polluted sites have evolved diverse resistance strategies, involving biosorption, bioprecipitation, biomineralization, biotransformation, and efflux mechanisms, under continuous exposure to Pb in human-impacted surroundings. These strategies employ a wide range of functional bioligands to capture Pb and render it inaccessible for leaching. Recent breakthroughs in molecular technology and understanding of lead resistance mechanisms offer the potential for utilizing microbes as biological tools in environmental risk assessment. Leveraging the specific affinity and sensitivity of bacterial regulators to Pb2+ ions, numerous lead biosensors have been designed and deployed worldwide to monitor Pb bioavailability in contaminated sites, even at trace levels. Besides, the ongoing degradation of croplands due to Pb pollution poses a significant challenge to meet the escalating global food demands. The accumulation of Pb in plant tissues jeopardizes both food safety and security while severely impacting plant growth. Exploring Pb-resistant plant growth-promoting rhizobacteria (PGPR) presents a promising sustainable approach to agricultural practices. The active associations of PGPR with host plants have shown enhancements in plant biomass and stress alleviation under Pb influence. They thus serve a dual purpose for plants grown in Pb-contaminated areas. This review aims to offer a comprehensive understanding of the role played by Pb-resistant soil-borne indigenous bacteria in expediting bioremediation and improving the growth of Pb-challenged plants essential for potential field application, thus broadening prospects for future research and development.
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Affiliation(s)
- Priyanka Pal
- Microbiology Laboratory, CAS, Department of Botany, Burdwan University, Burdwan, West Bengal 713104, India
| | - Krishnendu Pramanik
- Department of Botany, Cooch Behar Panchanan Barma University, Panchanan Nagar, Vivekananda Street, Cooch Behar, West Bengal 736101, India
| | - Sudip Kumar Ghosh
- Microbiology Laboratory, CAS, Department of Botany, Burdwan University, Burdwan, West Bengal 713104, India
| | - Sayanta Mondal
- Microbiology Laboratory, CAS, Department of Botany, Burdwan University, Burdwan, West Bengal 713104, India
| | - Tanushree Mondal
- Microbiology Laboratory, CAS, Department of Botany, Burdwan University, Burdwan, West Bengal 713104, India
| | - Tithi Soren
- Microbiology Laboratory, CAS, Department of Botany, Burdwan University, Burdwan, West Bengal 713104, India
| | - Tushar Kanti Maiti
- Microbiology Laboratory, CAS, Department of Botany, Burdwan University, Burdwan, West Bengal 713104, India.
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Li Q, Yang X, Li C, He A, He S, Li X, Zhang Y, Yao T. Comparison of bio-beads combined with Pseudomonas edaphica and three phosphate materials for lead immobilization: Performance, mechanism and plant growth. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 357:120797. [PMID: 38574707 DOI: 10.1016/j.jenvman.2024.120797] [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: 01/16/2024] [Revised: 03/25/2024] [Accepted: 03/28/2024] [Indexed: 04/06/2024]
Abstract
Phosphate materials (PMs) combine with phosphate solubilizing bacteria play an essential roles in lead (Pb) immobilization, but their resulting ability to reduce Pb bioavailability may vary depending on PMs used. In this study, Pseudomonas edaphica GAU-665 and three PMs: tricalcium phosphate, calcium phytate and nano-hydroxyapatite were respectively encapsulated into bio-beads by sodium alginate, which immobilization efficiency of Pb2+ were 99.11%, 97.76% and 99.02% at initial Pb2+ concentration of 200 mg L-1, respectively. The Pb2+ immobilization performance of bio-beads under different conditions and their organic acids secreted were examined. Most Pb2+ was immobilized by bio-beads through combined functions of adsorption, precipitation, ion exchange and biomineralization, accompanied by the formation of more stable compounds such as Pb3(PO4)2, Pb5(PO4)3OH and Pb5(PO4)3Cl. Meanwhile, pot experimental results indicated that the inoculation of CPhy (calcium phytate) bio-beads with PSB have highest biomass and root growth of oat (Avena sativa L.) in Pb-stressed compared with CK, which increased the content of chlorophyll b (167.51%) in shoot. In addition, the CPhy bio-beads enhance the peroxidase, catalase activities and reduce the malondialdehyde content to alleviating lead physiological toxicity in oat, which reductions the Pb accumulation in shoot (52.06%) and root (81.04%), and increased the residual fraction of Pb by 165.80% in soil. These findings suggest the bio-beads combined with P. edaphica GAU-665 and calcium phytate is an efficient Pb immobilization material and provided feasible way to improve safety agricultural production and Pb-contaminated soil remediation.
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Affiliation(s)
- Qi Li
- College of Grassland Science, Gansu Agricultural University, Lanzhou, 730070, Gansu, China; Key Laboratory of Grassland Ecosystem, Gansu Agricultural University, Ministry of Education, Lanzhou, 730070, Gansu, China
| | - Xiaolei Yang
- College of Grassland Science, Gansu Agricultural University, Lanzhou, 730070, Gansu, China; Key Laboratory of Grassland Ecosystem, Gansu Agricultural University, Ministry of Education, Lanzhou, 730070, Gansu, China
| | - Changning Li
- College of Grassland Science, Gansu Agricultural University, Lanzhou, 730070, Gansu, China; Key Laboratory of Grassland Ecosystem, Gansu Agricultural University, Ministry of Education, Lanzhou, 730070, Gansu, China
| | - Aolei He
- College of Grassland Science, Gansu Agricultural University, Lanzhou, 730070, Gansu, China; Key Laboratory of Grassland Ecosystem, Gansu Agricultural University, Ministry of Education, Lanzhou, 730070, Gansu, China
| | - Shanmu He
- College of Grassland Science, Gansu Agricultural University, Lanzhou, 730070, Gansu, China; Key Laboratory of Grassland Ecosystem, Gansu Agricultural University, Ministry of Education, Lanzhou, 730070, Gansu, China
| | - Xuemei Li
- College of Grassland Science, Gansu Agricultural University, Lanzhou, 730070, Gansu, China; Key Laboratory of Grassland Ecosystem, Gansu Agricultural University, Ministry of Education, Lanzhou, 730070, Gansu, China
| | - Ying Zhang
- College of Grassland Science, Gansu Agricultural University, Lanzhou, 730070, Gansu, China; Key Laboratory of Grassland Ecosystem, Gansu Agricultural University, Ministry of Education, Lanzhou, 730070, Gansu, China
| | - Tuo Yao
- College of Grassland Science, Gansu Agricultural University, Lanzhou, 730070, Gansu, China; Key Laboratory of Grassland Ecosystem, Gansu Agricultural University, Ministry of Education, Lanzhou, 730070, Gansu, China.
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Wu F, Li X, Wei P, Liu Z. Isolation and identification of a high-efficiency hexavalent uranium adsorption strain and preliminary study of the influencing factors and adsorption mechanism. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:26112-26122. [PMID: 38492141 DOI: 10.1007/s11356-024-32934-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Accepted: 03/11/2024] [Indexed: 03/18/2024]
Abstract
In this study, a bacterial strain Chryseobacterium bernardetii WK-3 was isolated from the rhizosphere soil of a uranium tailings in Southern China. It can efficiently adsorb hexavalent uranium with an adsorption ratio of 92.3%. The influence of different environmental conditions on the adsorption ratio of Chryseobacterium bernardetii strain WK-3 was investigated, and the adsorption mechanism was preliminarily discussed by scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS). The results showed that the optimal adsorption conditions for U(VI) by Chryseobacterium bernardetii strain WK-3 were pH = 5, temperature 30 ℃, NaCl concentration 1%, and inoculation volume 10%. When the initial concentration of U was 50 ~ 150 mg/L, the adsorption capacity of Chryseobacterium bernardetii strain WK-3 to U(VI) reached the maximum and maintained the equilibrium at 44 h. SEM-EDS results showed that phosphorus in cells participates in the interaction of uranyl ions, which may indicate that phosphate was produced during cell metabolism and was further combined to form U(VI)-phosphate minerals. In summary, Chryseobacterium bernardetii strain WK-3 would be a promising alternative for environmental uranium contamination remediation.
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Affiliation(s)
- Faming Wu
- State Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang, 330013, People's Republic of China
- Jiangxi Agricultural University, Nanchang, 330045, People's Republic of China
| | - Xiang Li
- State Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang, 330013, People's Republic of China
| | - Peng Wei
- State Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang, 330013, People's Republic of China
| | - Zhirong Liu
- State Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang, 330013, People's Republic of China.
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Olaya‐Abril A, Biełło K, Rodríguez‐Caballero G, Cabello P, Sáez LP, Moreno‐Vivián C, Luque‐Almagro VM, Roldán MD. Bacterial tolerance and detoxification of cyanide, arsenic and heavy metals: Holistic approaches applied to bioremediation of industrial complex wastes. Microb Biotechnol 2024; 17:e14399. [PMID: 38206076 PMCID: PMC10832572 DOI: 10.1111/1751-7915.14399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 12/19/2023] [Accepted: 12/22/2023] [Indexed: 01/12/2024] Open
Abstract
Cyanide is a highly toxic compound that is found in wastewaters generated from different industrial activities, such as mining or jewellery. These residues usually contain high concentrations of other toxic pollutants like arsenic and heavy metals that may form different complexes with cyanide. To develop bioremediation strategies, it is necessary to know the metabolic processes involved in the tolerance and detoxification of these pollutants, but most of the current studies are focused on the characterization of the microbial responses to each one of these environmental hazards individually, and the effect of co-contaminated wastes on microbial metabolism has been hardly addressed. This work summarizes the main strategies developed by bacteria to alleviate the effects of cyanide, arsenic and heavy metals, analysing interactions among these toxic chemicals. Additionally, it is discussed the role of systems biology and synthetic biology as tools for the development of bioremediation strategies of complex industrial wastes and co-contaminated sites, emphasizing the importance and progress derived from meta-omic studies.
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Affiliation(s)
- Alfonso Olaya‐Abril
- Departamento de Bioquímica y Biología Molecular, Edificio Severo Ochoa, Campus de RabanalesUniversidad de CórdobaCórdobaSpain
| | - Karolina Biełło
- Departamento de Bioquímica y Biología Molecular, Edificio Severo Ochoa, Campus de RabanalesUniversidad de CórdobaCórdobaSpain
| | - Gema Rodríguez‐Caballero
- Departamento de Bioquímica y Biología Molecular, Edificio Severo Ochoa, Campus de RabanalesUniversidad de CórdobaCórdobaSpain
| | - Purificación Cabello
- Departamento de Botánica, Ecología y Fisiología Vegetal, Edificio Celestino Mutis, Campus de RabanalesUniversidad de CórdobaCórdobaSpain
| | - Lara P. Sáez
- Departamento de Bioquímica y Biología Molecular, Edificio Severo Ochoa, Campus de RabanalesUniversidad de CórdobaCórdobaSpain
| | - Conrado Moreno‐Vivián
- Departamento de Bioquímica y Biología Molecular, Edificio Severo Ochoa, Campus de RabanalesUniversidad de CórdobaCórdobaSpain
| | - Víctor Manuel Luque‐Almagro
- Departamento de Bioquímica y Biología Molecular, Edificio Severo Ochoa, Campus de RabanalesUniversidad de CórdobaCórdobaSpain
| | - María Dolores Roldán
- Departamento de Bioquímica y Biología Molecular, Edificio Severo Ochoa, Campus de RabanalesUniversidad de CórdobaCórdobaSpain
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6
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Elizabeth George S, Wan Y. Microbial functionalities and immobilization of environmental lead: Biogeochemical and molecular mechanisms and implications for bioremediation. JOURNAL OF HAZARDOUS MATERIALS 2023; 457:131738. [PMID: 37285788 PMCID: PMC11249206 DOI: 10.1016/j.jhazmat.2023.131738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2023] [Revised: 05/26/2023] [Accepted: 05/28/2023] [Indexed: 06/09/2023]
Abstract
The increasing environmental and human health concerns about lead in the environment have stimulated scientists to search for microbial processes as innovative bioremediation strategies for a suite of different contaminated media. In this paper, we provide a compressive synthesis of existing research on microbial mediated biogeochemical processes that transform lead into recalcitrant precipitates of phosphate, sulfide, and carbonate, in a genetic, metabolic, and systematics context as they relate to application in both laboratory and field immobilization of environmental lead. Specifically, we focus on microbial functionalities of phosphate solubilization, sulfate reduction, and carbonate synthesis related to their respective mechanisms that immobilize lead through biomineralization and biosorption. The contributions of specific microbes, both single isolates or consortia, to actual or potential applications in environmental remediation are discussed. While many of the approaches are successful under carefully controlled laboratory conditions, field application requires optimization for a host of variables, including microbial competitiveness, soil physical and chemical parameters, metal concentrations, and co-contaminants. This review challenges the reader to consider bioremediation approaches that maximize microbial competitiveness, metabolism, and the associated molecular mechanisms for future engineering applications. Ultimately, we outline important research directions to bridge future scientific research activities with practical applications for bioremediation of lead and other toxic metals in environmental systems.
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Affiliation(s)
- S Elizabeth George
- US EPA Office of Research and Development, Center for Environmental Measurement and Modeling, Gulf Ecosystem Measurement and Modeling Division, One Sabine Island Drive, Gulf Breeze, FL 32561, USA
| | - Yongshan Wan
- US EPA Office of Research and Development, Center for Environmental Measurement and Modeling, Gulf Ecosystem Measurement and Modeling Division, One Sabine Island Drive, Gulf Breeze, FL 32561, USA.
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Han LJ, Li JS, Chen Z, Xue Q. Stabilization of Pb(II) in wastewater and tailings by commercial bacteria through microbially induced phosphate precipitation (MIPP). THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 868:161628. [PMID: 36657686 DOI: 10.1016/j.scitotenv.2023.161628] [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: 11/01/2022] [Revised: 12/20/2022] [Accepted: 01/11/2023] [Indexed: 06/17/2023]
Abstract
Microbially induced phosphate precipitation (MIPP) is an effective and eco-friendly method for Pb(II) stabilization. The phosphate-solubilizing microorganisms (PSM) for MIPP are commonly isolated from Pb(II)-contaminated sites through a series of intricate and time-consuming enrichment and purification processes. This research used ready-made commercial bacteria to develop a simple MIPP process. Bacillus subtilis (BS, CCTCC AB 98002) was selected from two commercial PSM strains owing to more effective Pb(II) removal. Compared to the most isolated microorganisms, BS released more than twice as much inorganic phosphorus (Pi) as well as had a high-level Pb(II) tolerance. BS could remove >99% of Pb(II) from 500 mg/L Pb(II)-containing water at the optimal 0.05 M sodium glycerophosphate (SGP), pH 7-9, and ≤0.03 M MgCl2, outperforming most isolated microorganisms. In addition, BS could mitigate the contamination risk of the lead‑zinc tailings, by reducing the readily leachable Pb(II) concentration from 0.81 mg/L (over the regulatory limit of 0.1 mg/L) to 0.00042 mg/L. The unstable Pb(II) in the solution and tailings was ultimately stabilized to Pb5(PO4)3Cl after the SGP phosphorlysis and phosphate precipitation processes. In conclusion, commercial BS is a superior alternative to isolated microorganisms for MIPP on Pb(II) stabilization. The simple-processed and high-effective BS-based MIPP provides the MIPP method a new insight for widespread implementation in the remediation of heavy metals-containing wastewater, soil, and waste.
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Affiliation(s)
- Li-Jun Han
- State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, China; University of Chinese Academy of Science, Beijing 100049, China
| | - Jiang-Shan Li
- State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, China; IRSM-CAS/HK PolyU Joint Laboratory on Solid Waste Science, Wuhan 430071, China.
| | - Zhen Chen
- State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, China
| | - Qiang Xue
- State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, China.
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He N, Ran M, Hu L, Jiang C, Liu Y. Periplasmic space is the key location for Pb(II) biomineralization by Burkholderia cepacia. JOURNAL OF HAZARDOUS MATERIALS 2023; 445:130465. [PMID: 36436453 DOI: 10.1016/j.jhazmat.2022.130465] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Revised: 11/11/2022] [Accepted: 11/22/2022] [Indexed: 06/16/2023]
Abstract
Phosphate solubilizing bacteria (PSB) induced phosphate precipitation is considered as an effective method for Pb(II) removal through the formation of stable Pb(II)-phosphate compound, but the location of end-products is still unclear. Herein, the PSB strain of Burkholderia cepacia (B. cepacia) coupled with the hydroxyapatite (HAP) was used in this study to investigate the Pb(II) removal mechanism and the biomineralization location. The dissolving phosphate of three particle sizes of HAP and Pb(II) resistant capabilities, and the effect factors such as HAP dosage, initial concentrations of Pb(II), pH, temperature, and different treatments were determined. The results indicated that the highest soluble phosphate could reach 224.85 mg/L in a 200 nm HAP medium and the highest removal efficiency of Pb(II) was about 96.32 %. Additionally, it was interesting that Pb(II) was mainly located in the periplasmic space through the cellular distribution experiment, which was further demonstrated by scanning electron microscope (SEM) and transmission electron microscopy (TEM). Besides, the characterization results showed that the functional groups such as amide, hydroxy, carboxy and phosphate played an important role in Pb(II) biomineralization, and the free Pb(II) in aqueous solution could be transformed into pyromorphite through phosphate dissolution, extracellular adsorption/complexation, and intracellular precipitation.
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Affiliation(s)
- Ni He
- School of Minerals Processing and Bioengineering, Key Laboratory of Biohydrometallurgy of Ministry of Education, Central South University, Changsha 410083, China
| | - Maodi Ran
- School of Minerals Processing and Bioengineering, Key Laboratory of Biohydrometallurgy of Ministry of Education, Central South University, Changsha 410083, China
| | - Liang Hu
- School of Minerals Processing and Bioengineering, Key Laboratory of Biohydrometallurgy of Ministry of Education, Central South University, Changsha 410083, China.
| | - Chunyangzi Jiang
- School of Minerals Processing and Bioengineering, Key Laboratory of Biohydrometallurgy of Ministry of Education, Central South University, Changsha 410083, China
| | - Yayuan Liu
- School of Minerals Processing and Bioengineering, Key Laboratory of Biohydrometallurgy of Ministry of Education, Central South University, Changsha 410083, China
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Chen Z, Huang Z, Liu H, Wang H, Wei Z. Pb 0 flue gas biosorption in denitrifying MBfR: Characteristics and binding ability of extracellular polymeric substances. CHEMOSPHERE 2023; 314:137703. [PMID: 36587914 DOI: 10.1016/j.chemosphere.2022.137703] [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: 06/10/2022] [Revised: 12/08/2022] [Accepted: 12/29/2022] [Indexed: 06/17/2023]
Abstract
Pb0 in flue gas which is ubiquitous in the environment, poses a certain threat to human and ecology, but the study on EPS-dependent stabilization of lead to remove Pb0 from flue gas remains insufficient. In this investigation, the characteristics and heavy metals-binding ability of four EPS fractions were evaluated. The EPS were extracted from denitrifying membrane biofilm reactor (MBfR) and divided into slime EPS (S-EPS), loosely-bound EPS (LB-EPS), tightly-bound EPS (TB-EPS) and EPS in circulating flow (Y-EPS). The S, LB, TB-EPS related to Pb stabilization on biofilm need more attention. Compared to Pb-S-EPS (0.013 mg g-1) and Pb-LB-EPS (0.13 mg g-1), the Pb-TB-EPS (0.26 mg g-1) was mainly stable form of vapor Pb0, since TB-EPS's higher content (30.67-82.44 mg g-1 VSS), proteins (13.47-36.32 mg g-1 VSS) and polysaccharides (9.37-32.48 mg g-1 VSS) concentration. Particularly, proteins related ligands were more effective in S, LB, TB-EPS dependent adsorption of Pb, complexing with hydrophobic acid ligands further strengthened in TB-EPS adsorption. The Pb-EPS complex formed via binding with functional groups (such as O-H, N-H, C-H and CC) on EPS, also facilitated by loose structure of proteins. This study enlightens the researchers on the bio-treatment and EPS-dependent biosorption of Pb0 in flue gas in denitrifying MBfR.
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Affiliation(s)
- Zhuoyao Chen
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Guangzhou, 510006, China
| | - Zhenshan Huang
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Guangzhou, 510006, China
| | - Haixu Liu
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Guangzhou, 510006, China
| | - Huiying Wang
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Guangzhou, 510006, China
| | - Zaishan Wei
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Guangzhou, 510006, China.
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Newsome L, Falagán C. The Microbiology of Metal Mine Waste: Bioremediation Applications and Implications for Planetary Health. GEOHEALTH 2021; 5:e2020GH000380. [PMID: 34632243 PMCID: PMC8490943 DOI: 10.1029/2020gh000380] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 08/17/2021] [Accepted: 08/20/2021] [Indexed: 05/13/2023]
Abstract
Mine wastes pollute the environment with metals and metalloids in toxic concentrations, causing problems for humans and wildlife. Microorganisms colonize and inhabit mine wastes, and can influence the environmental mobility of metals through metabolic activity, biogeochemical cycling and detoxification mechanisms. In this article we review the microbiology of the metals and metalloids most commonly associated with mine wastes: arsenic, cadmium, chromium, copper, lead, mercury, nickel and zinc. We discuss the molecular mechanisms by which bacteria, archaea, and fungi interact with contaminant metals and the consequences for metal fate in the environment, focusing on long-term field studies of metal-impacted mine wastes where possible. Metal contamination can decrease the efficiency of soil functioning and essential element cycling due to the need for microbes to expend energy to maintain and repair cells. However, microbial communities are able to tolerate and adapt to metal contamination, particularly when the contaminant metals are essential elements that are subject to homeostasis or have a close biochemical analog. Stimulating the development of microbially reducing conditions, for example in constructed wetlands, is beneficial for remediating many metals associated with mine wastes. It has been shown to be effective at low pH, circumneutral and high pH conditions in the laboratory and at pilot field-scale. Further demonstration of this technology at full field-scale is required, as is more research to optimize bioremediation and to investigate combined remediation strategies. Microbial activity has the potential to mitigate the impacts of metal mine wastes, and therefore lessen the impact of this pollution on planetary health.
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Affiliation(s)
- Laura Newsome
- Camborne School of Mines and Environment and Sustainability InstituteUniversity of ExeterPenrynUK
| | - Carmen Falagán
- Camborne School of Mines and Environment and Sustainability InstituteUniversity of ExeterPenrynUK
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Experimental and modeling studies of competitive Pb (II) and Cd (II) bioaccumulation by Aspergillus niger. Appl Microbiol Biotechnol 2021; 105:6477-6488. [PMID: 34424384 DOI: 10.1007/s00253-021-11497-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 08/01/2021] [Accepted: 08/03/2021] [Indexed: 10/20/2022]
Abstract
Co-existence of toxic metals causes complex toxicity to microorganisms during bioremediation in water and soil. This study investigated the immobilization of Pb2+ and Cd2+ by fungus Aspergillus niger, which has been widely applied to environmental remediation. Five treatments were set, i.e., CK (no toxic metals), Pb2+ only, Cd2+ only, Pb2+/Cd2+ = 1:1(molar ratio), and Pb2+/Cd2+ = 2:1. Cadmium induced strong toxicity to the fungus, and maintained the high toxicity during incubation. However, as Pb/Cd ratio increased from 0 to 2, the removal rates of Cd2+ by A. niger were raised from 30 to 50%. The elevated activities of pyruvate dehydrogenase (PDH) and citrate synthetase (CS) enzymes confirmed that Pb addition could stimulate the growth of A. niger. For instance, citric acid concentrations and CS activities were 463.22 mg/L and 78.37 nmol/min/g, respectively, during 3-day incubation as Pb/Cd = 1. However, these two values were as low as ~ 50 with addition of only Cd. It was hence assumed that appropriate co-existence of Pb2+ enhanced microbial activity by promoting TCA cycle of the fungus. Moreover, the SEM analysis and geochemical modeling demonstrated that Pb2+ cations were more easily adsorbed and mineralized on A. niger with respect to Cd2+. Therefore, instead of intensifying metal toxicity, the addition of appropriate Pb actually weakened Cd toxicity to the fungus. This study sheds a bright future on application of A. niger to the remediation of polluted water with co-existence of Pb and Cd. KEY POINTS: • Cd2+ significantly inhibited P consumption, suggesting its high toxicity to A. niger. • Pb2+ stimulated the growth of A. niger by promoting TCA cycle in the cells. • Cd2+ removal by A. niger were improved with co-existence of Pb2+.
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12
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Zhong J, Hu X, Liu X, Cui X, Lv Y, Tang C, Zhang M, Li H, Qiu L, Sun W. Isolation and Identification of Uranium Tolerant Phosphate-Solubilizing Bacillus spp. and Their Synergistic Strategies to U(VI) Immobilization. Front Microbiol 2021; 12:676391. [PMID: 34326819 PMCID: PMC8313988 DOI: 10.3389/fmicb.2021.676391] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Accepted: 05/03/2021] [Indexed: 11/13/2022] Open
Abstract
The remediation of uranium (U) through phosphate-solubilizing bacteria (PSB) is an emerging technique as well as an interesting phenomenon for transforming mobile U into stable minerals in the environment. While studies are well needed for in-depth understanding of the mechanism of U(VI) immobilization by PSB. In this study, two PSB were isolated from a U-tailing repository site. These bacterial strains (ZJ-1 and ZJ-3) were identified as Bacillus spp. by the sequence analysis of 16S ribosomal RNA (rRNA) genes. Incubation of PSB in liquid medium showed that the isolate ZJ-3 could solubilize more than 230 mg L-1 P from glycerol-3-phosphate and simultaneously removed over 70% of 50 mg L-1 U(VI) within 1 h. During this process, the rapid appearance of yellow precipitates was observed. The microscopic and spectroscopic analysis demonstrated that the precipitates were associated with U-phosphate compound in the form of saleeite-like substances. Besides, scanning electron microscopy coupled with energy-dispersive X-ray (SEM-EDS) and Fourier transform infrared spectroscopy (FTIR) analysis of the precipitates confirmed that the extracellular polymeric substances (EPS) might also play a key role in U sequestration. Furthermore, SEM and FTIR analysis revealed that part of U(VI) was adsorbed on the bacterial surface through cellular phosphate, hydroxy, carboxyl, and amide groups. This study provides new insights into the synergistic strategies enhancing U immobilization rates by Bacillus spp. that uses glycerol-3-phosphate as the phosphorus source, the process of which contributes to harmful pollutant biodegradation.
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Affiliation(s)
- Juan Zhong
- GRINM Resources and Environment Tech. Co., Ltd., Beijing, China.,National Engineering Laboratory of Biohydrometallurgy, GRINM Group Co., Ltd., Beijing, China.,GRIMAT Engineering Institute Co., Ltd., Beijing, China
| | - Xuewu Hu
- GRINM Resources and Environment Tech. Co., Ltd., Beijing, China.,National Engineering Laboratory of Biohydrometallurgy, GRINM Group Co., Ltd., Beijing, China.,School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing, China
| | - Xingyu Liu
- GRINM Resources and Environment Tech. Co., Ltd., Beijing, China.,National Engineering Laboratory of Biohydrometallurgy, GRINM Group Co., Ltd., Beijing, China
| | - Xinglan Cui
- GRINM Resources and Environment Tech. Co., Ltd., Beijing, China.,National Engineering Laboratory of Biohydrometallurgy, GRINM Group Co., Ltd., Beijing, China
| | - Ying Lv
- GRINM Resources and Environment Tech. Co., Ltd., Beijing, China.,National Engineering Laboratory of Biohydrometallurgy, GRINM Group Co., Ltd., Beijing, China
| | - Chuiyun Tang
- GRINM Resources and Environment Tech. Co., Ltd., Beijing, China.,National Engineering Laboratory of Biohydrometallurgy, GRINM Group Co., Ltd., Beijing, China
| | - Mingjiang Zhang
- GRINM Resources and Environment Tech. Co., Ltd., Beijing, China.,National Engineering Laboratory of Biohydrometallurgy, GRINM Group Co., Ltd., Beijing, China
| | - Hongxia Li
- GRINM Resources and Environment Tech. Co., Ltd., Beijing, China.,National Engineering Laboratory of Biohydrometallurgy, GRINM Group Co., Ltd., Beijing, China
| | - Lang Qiu
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou, China
| | - Weimin Sun
- Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou, China
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13
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Jroundi F, Martinez-Ruiz F, Merroun ML, Gonzalez-Muñoz MT. Exploring bacterial community composition in Mediterranean deep-sea sediments and their role in heavy metal accumulation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 712:135660. [PMID: 31791772 DOI: 10.1016/j.scitotenv.2019.135660] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 11/18/2019] [Accepted: 11/19/2019] [Indexed: 06/10/2023]
Abstract
The role of microbial processes in bioaccumulation of major and trace elements has been broadly demonstrated. However, microbial communities from marine sediments have been poorly investigated to this regard. In marine environments, particularly under high anthropogenic pressure, heavy metal accumulation increases constantly, which may lead to significant environmental issues. A better knowledge of bacterial diversity and its capability to bioaccumulate metals is essential to face environmental quality assessment. The oligotrophic westernmost Mediterranean, which is highly sensitive to environmental changes and subjected to increasing anthropogenic pressure, was selected for this study. A sediment core spanning the last two millennia was sampled at two intervals, with ages corresponding to 140 (S1) and 1400 (S2) yr BP. High-throughput sequencing showed an abundance of Bacillus, Micrococcus, unclassified members of Planococcaceae, Anaerolineaceae, Planctomycetaceae, Microlunatus, and Microbacterium in both intervals, with slight differences in their abundance, along with newly detected ones in S2, i.e., Propionibacterium, Fictibacillus, Thalassobacillus, and Bacteroides. Canonical correspondence analysis (CCA) and co-occurrence patterns confirmed strong correlations among the taxa and the environmental parameters, suggesting either shared and preferred environmental conditions, or the performance of functions similar to or complementary to each other. These results were further confirmed using culture-dependent methods. The diversity of the culturable bacterial community revealed a predominance of Bacillus, and Micrococcus or Kocuria. The interaction of these bacterial communities with selected heavy metals (Cu, Cr, Zn and Pb) was also investigated, and their capacity of bioaccumulating metals within the cells and/or in the extracellular polymeric substances (EPS) is demonstrated. Interestingly, biomineralization of Pb resulted in the precipitation of Pb phosphates (pyromorphite). Our study supports that remnants of marine bacterial communities can survive in deep-sea sediments over thousands of years. This is extremely important in terms of bioremediation, in particular when considering possible environmentally friendly strategies to bioremediate inorganic contaminants.
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Affiliation(s)
- Fadwa Jroundi
- Department of Microbiology, Faculty of Science, University of Granada, Avda. Fuentenueva s/n, 18071 Granada, Spain.
| | - Francisca Martinez-Ruiz
- Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Av. de las Palmeras 4, 18100 (Armilla) Granada, Spain.
| | - Mohamed L Merroun
- Department of Microbiology, Faculty of Science, University of Granada, Avda. Fuentenueva s/n, 18071 Granada, Spain.
| | - María Teresa Gonzalez-Muñoz
- Department of Microbiology, Faculty of Science, University of Granada, Avda. Fuentenueva s/n, 18071 Granada, Spain.
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14
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Mohd S, Kushwaha AS, Shukla J, Mandrah K, Shankar J, Arjaria N, Saxena PN, Khare P, Narayan R, Dixit S, Siddiqui MH, Tuteja N, Das M, Roy SK, Kumar M. Fungal mediated biotransformation reduces toxicity of arsenic to soil dwelling microorganism and plant. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2019; 176:108-118. [PMID: 30925326 DOI: 10.1016/j.ecoenv.2019.03.053] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Revised: 03/11/2019] [Accepted: 03/13/2019] [Indexed: 05/24/2023]
Abstract
Rhizospheric and plant root associated microbes generally play a protective role against arsenic toxicity in rhizosphere. Rhizospheric microbial interaction influences arsenic (As) detoxification/mobilization into crop plants and its level of toxicity and burden. In the present investigation, we have reported a rhizospheric fungi Aspergillus flavus from an As contaminated rice field, which has capability to grow at high As concentration and convert soluble As into As particles. These As particles showed a reduced toxicity to soil dwelling bacteria, fungi, plant and slime mold. It does not disrupt membrane potential, inner/outer membrane integrity and survival of the free N2 fixating bacteria. In arbuscular mycorrhiza like endophytic fungi Piriformospora indica, these As particles does not influence mycelial growth and plant beneficial parameters such as phosphate solubilizing enzyme rAPase secretion and plant root colonization. Similarly, it does not affect plant growth and chlorophyll content negatively in rice plant. However, these As particles showed a poor absorption and mobilization in plant. These As particle also does not affect attachment process and survival of amoeboid cells in slime mold, Dictyostelium discoideum. This study suggests that the process of conversion of physical and chemical properties of arsenic during transformation, decides the toxicity of arsenic particles in the rhizospheric environment. This phenomenon is of environmental significance, not only in reducing arsenic toxicity but also in the survival of healthy living organism in arsenic-contaminated rhizospheric environment.
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Affiliation(s)
- Shayan Mohd
- Environmental Toxicology Group, CSIR-Indian Institute of Toxicology Research (CSIR-IITR), Vishvigyan Bhavan, 31, Mahatma Gandhi Marg, Lucknow, 226 001, India; Department of Bioengineering, Faculty of Engineering, Integral University, Dasauli, Kursi Road, Lucknow, 226026, India
| | - Aparna Singh Kushwaha
- Environmental Toxicology Group, CSIR-Indian Institute of Toxicology Research (CSIR-IITR), Vishvigyan Bhavan, 31, Mahatma Gandhi Marg, Lucknow, 226 001, India; Academy of Scientific and Innovative Research (AcSIR), CSIR-IITR Campus, Vishvigyan Bhavan, 31, Mahatma Gandhi Marg, Lucknow, 226 001, Uttar Pradesh, India
| | - Jagriti Shukla
- Environmental Toxicology Group, CSIR-Indian Institute of Toxicology Research (CSIR-IITR), Vishvigyan Bhavan, 31, Mahatma Gandhi Marg, Lucknow, 226 001, India; Academy of Scientific and Innovative Research (AcSIR), CSIR-IITR Campus, Vishvigyan Bhavan, 31, Mahatma Gandhi Marg, Lucknow, 226 001, Uttar Pradesh, India
| | - Kapil Mandrah
- Regulatory Toxicology Group, CSIR-Indian Institute of Toxicology Research (CSIR-IITR), Vishvigyan Bhavan, 31, Mahatma Gandhi Marg, Lucknow, 226 001, India; Academy of Scientific and Innovative Research (AcSIR), CSIR-IITR Campus, Vishvigyan Bhavan, 31, Mahatma Gandhi Marg, Lucknow, 226 001, Uttar Pradesh, India
| | - Jai Shankar
- Electron Microscope Facility, CSIR-Indian Institute of Toxicology Research (CSIR-IITR), Vishvigyan Bhavan, 31, Mahatma Gandhi Marg, Lucknow, 226 001, India
| | - Nidhi Arjaria
- Electron Microscope Facility, CSIR-Indian Institute of Toxicology Research (CSIR-IITR), Vishvigyan Bhavan, 31, Mahatma Gandhi Marg, Lucknow, 226 001, India
| | - Prem Narain Saxena
- Electron Microscope Facility, CSIR-Indian Institute of Toxicology Research (CSIR-IITR), Vishvigyan Bhavan, 31, Mahatma Gandhi Marg, Lucknow, 226 001, India
| | - Puneet Khare
- Flow Cytometry Facility, CSIR-Indian Institute of Toxicology Research (CSIR-IITR), Vishvigyan Bhavan, 31, Mahatma Gandhi Marg, Lucknow, 226 001, India
| | - Ram Narayan
- Confocal Microscope Facility, CSIR-Indian Institute of Toxicology Research (CSIR-IITR), Vishvigyan Bhavan, 31, Mahatma Gandhi Marg, Lucknow, 226 001, India
| | - Sumita Dixit
- Food, Drug and Chemical Toxicology Group, CSIR-Indian Institute of Toxicology Research (CSIR-IITR), Vishvigyan Bhavan, 31, Mahatma Gandhi Marg, Lucknow, 226 001, India
| | - Mohd Haris Siddiqui
- Department of Bioengineering, Faculty of Engineering, Integral University, Dasauli, Kursi Road, Lucknow, 226026, India
| | - Narendra Tuteja
- International Centre of Genetic Engineering and Biotechnology, Aruna Asif Ali Road, New Delhi, 110067, India
| | - Mukul Das
- Food, Drug and Chemical Toxicology Group, CSIR-Indian Institute of Toxicology Research (CSIR-IITR), Vishvigyan Bhavan, 31, Mahatma Gandhi Marg, Lucknow, 226 001, India
| | - Somendu Kumar Roy
- Regulatory Toxicology Group, CSIR-Indian Institute of Toxicology Research (CSIR-IITR), Vishvigyan Bhavan, 31, Mahatma Gandhi Marg, Lucknow, 226 001, India; Academy of Scientific and Innovative Research (AcSIR), CSIR-IITR Campus, Vishvigyan Bhavan, 31, Mahatma Gandhi Marg, Lucknow, 226 001, Uttar Pradesh, India
| | - Manoj Kumar
- Environmental Toxicology Group, CSIR-Indian Institute of Toxicology Research (CSIR-IITR), Vishvigyan Bhavan, 31, Mahatma Gandhi Marg, Lucknow, 226 001, India; Academy of Scientific and Innovative Research (AcSIR), CSIR-IITR Campus, Vishvigyan Bhavan, 31, Mahatma Gandhi Marg, Lucknow, 226 001, Uttar Pradesh, India.
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15
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Jiang Z, Jiang L, Zhang L, Su M, Tian D, Wang T, Sun Y, Nong Y, Hu S, Wang S, Li Z. Contrasting the Pb (II) and Cd (II) tolerance of Enterobacter sp. via its cellular stress responses. Environ Microbiol 2019; 22:1507-1516. [PMID: 31215728 DOI: 10.1111/1462-2920.14719] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 06/05/2019] [Accepted: 06/14/2019] [Indexed: 11/29/2022]
Abstract
Successful application of microorganisms to heavy metal remediation depends on their resistance to toxic metals. This study contrasted the differences of tolerant mechanisms between Pb2+ and Cd2+ in Enterobacter sp. Microbial respiration and production of formic acid showed that Enterobacter sp. had a higher tolerant concentration of Pb (>1000 mg l-1 ) than Cd (about 200 mg l-1 ). Additionally, SEM confirmed that most of Pb and Cd nanoparticles (NPs) were adsorbed onto cell membrane. The Cd stress, even at low concentration (50 mg l-1 ), significantly enlarged the sizes of cells. The cellular size raised from 0.4 × 1.0 to 0.9 × 1.6 μm on average, inducing a platelet-like shape. In contrast, Pb cations did not stimulate such enlargement even up to 1000 mg l-1 . Moreover, Cd NPs were adsorbed homogeneously by almost all the bacterial cells under TEM. However, only a few cells work as 'hot spots' on the sorption of Pb NPs. The heterogeneous sorption might result from a 'self-sacrifice' mechanism, i.e., some cells at a special life stage contributed mostly to Pb sorption. This mechanism, together with the lower mobility of Pb cations, caused higher microbial tolerance and removal efficiency towards Pb2+ . This study sheds evident contrasts of bacterial resistance to the two most common heavy metals.
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Affiliation(s)
- Zhongquan Jiang
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, China
| | - Liu Jiang
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, China
| | - Lin Zhang
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, China.,Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, Nanjing Agricultural University, Nanjing, 210095, China
| | - Mu Su
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, China
| | - Da Tian
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, China
| | - Tong Wang
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, China
| | - Yalin Sun
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, China
| | - Ying Nong
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, China
| | - Shuijin Hu
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, China.,Department of Entomology & Plant Pathology, North Carolina State University, Raleigh, NC, 27695, USA
| | - Shimei Wang
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, China.,Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, Nanjing Agricultural University, Nanjing, 210095, China
| | - Zhen Li
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, 210095, China.,Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, Nanjing Agricultural University, Nanjing, 210095, China
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