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Muñoz-Villagrán C, Grossolli-Gálvez J, Acevedo-Arbunic J, Valenzuela X, Ferrer A, Díez B, Levicán G. Characterization and genomic analysis of two novel psychrotolerant Acidithiobacillus ferrooxidans strains from polar and subpolar environments. Front Microbiol 2022; 13:960324. [PMID: 36090071 PMCID: PMC9449456 DOI: 10.3389/fmicb.2022.960324] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 08/01/2022] [Indexed: 11/13/2022] Open
Abstract
The bioleaching process is carried out by aerobic acidophilic iron-oxidizing bacteria that are mainly mesophilic or moderately thermophilic. However, many mining sites are located in areas where the mean temperature is lower than the optimal growth temperature of these microorganisms. In this work, we report the obtaining and characterization of two psychrotolerant bioleaching bacterial strains from low-temperature sites that included an abandoned mine site in Chilean Patagonia (PG05) and an acid rock drainage in Marian Cove, King George Island in Antarctic (MC2.2). The PG05 and MC2.2 strains showed significant iron-oxidation activity and grew optimally at 20°C. Genome sequence analyses showed chromosomes of 2.76 and 2.84 Mbp for PG05 and MC2.2, respectively, and an average nucleotide identity estimation indicated that both strains clustered with the acidophilic iron-oxidizing bacterium Acidithiobacillus ferrooxidans. The Patagonian PG05 strain had a high content of genes coding for tolerance to metals such as lead, zinc, and copper. Concordantly, electron microscopy revealed the intracellular presence of polyphosphate-like granules, likely involved in tolerance to metals and other stress conditions. The Antarctic MC2.2 strain showed a high dosage of genes for mercury resistance and low temperature adaptation. This report of cold-adapted cultures of the At. ferrooxidans species opens novel perspectives to satisfy the current challenges of the metal bioleaching industry.
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Affiliation(s)
- Claudia Muñoz-Villagrán
- Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile (USACH), Santiago, Chile
| | - Jonnathan Grossolli-Gálvez
- Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile (USACH), Santiago, Chile
| | - Javiera Acevedo-Arbunic
- Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile (USACH), Santiago, Chile
| | - Ximena Valenzuela
- Programa de Biorremediación, Campus Patagonia, Universidad Austral de Chile, Valdivia, Chile
| | - Alonso Ferrer
- Núcleo de Química y Bioquímica, Facultad de Ciencias, Ingeniería y Tecnología, Universidad Mayor, Santiago, Chile
| | - Beatriz Díez
- Departamento de Genética Molecular y Microbiología, Pontificia Universidad Católica de Chile, Santiago, Chile
- Center for Climate and Resilience Research (CR)2, Santiago, Chile
- Center for Genome Regulation (CRG), Santiago, Chile
| | - Gloria Levicán
- Departamento de Biología, Facultad de Química y Biología, Universidad de Santiago de Chile (USACH), Santiago, Chile
- *Correspondence: Gloria Levicán,
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Brooks SC, Riscassi AL, Miller CL, Lowe KA, Yin X, Mehlhorn TL. Diel mercury concentration variations in a mercury-impacted stream. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2022; 24:1195-1211. [PMID: 35829655 DOI: 10.1039/d2em00142j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Filtered and particulate mercury (Hg) and methylmercury (MMHg), and associated water chemistry parameters, were evaluated bi-hourly for several 30 h periods during the summer and winter seasons at several distinct locations (downstream forested, midstream urban/suburban, upstream industrial) along a creek contaminated with high levels of inorganic Hg to determine if biogeochemical Hg and MMHg cycles respond to the daily photocycle. In summer particulate Hg and MMHg concentrations doubled overnight (excluding the upstream industrial site) concurrent with increases in turbidity and total suspended sediment; no such pattern was evident in winter. Seasonal and diel changes in the activity of macrobiota affecting the suspension of contaminated sediments are likely responsible for these patterns as other potential explanatory variables (e.g., instrument drift, pH, discharge) could not account for the range and timing of our observations. Diel patterns in filtered Hg (HgD) were significant only at locations and times of the year when channel shading was not present and daytime concentrations increased 22-89% above nighttime minima likely caused by direct and indirect photochemical reactions. Relationships between HgD and dissolved organic carbon (DOC) concentration or character were inconsistent between sites. Unlike HgD, there were significant diel patterns in filtered MMHg (MMHgD) at all sites and times of year, with summer concentrations peaking in mid to late afternoon while the timing differed in winter, with concentrations peaking after sunset. Daily variability in MMHgD concentration ranged between 25 and 75%. The results imply key controls on net methylation occur within the stream or on the stream bed and include factors such as small-scale temperature changes in the water column and photosynthetic activity of stream biofilm. With respect to stream monitoring, results from this study indicate (1) consistent timing in stream Hg and MMHg sampling is required for accurate assessment of long-term trends, (2) in situ measurements of turbidity can be used to quantify diel dynamics of both particulate Hg and MMHg concentrations, and (3) in situ fluorescing dissolved organic matter (FDOM), a potential proxy for DOC, was not capable of resolving diel dynamics of filtered Hg or MMHg.
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Affiliation(s)
- Scott C Brooks
- Oak Ridge National Laboratory, Environmental Sciences Division, PO Box 2008, MS 6038, Oak Ridge, TN, 37831-6038, USA.
| | - Ami L Riscassi
- University of Virginia, Environmental Sciences Department, 291 McCormick Rd., Charlottesville, VA, USA
| | - Carrie L Miller
- Theoretical and Applied Science, Ramapo College of New Jersey, Mahwah, New Jersey, USA
| | - Kenneth A Lowe
- Oak Ridge National Laboratory, Environmental Sciences Division, PO Box 2008, MS 6038, Oak Ridge, TN, 37831-6038, USA.
| | - Xiangping Yin
- Oak Ridge National Laboratory, Environmental Sciences Division, PO Box 2008, MS 6038, Oak Ridge, TN, 37831-6038, USA.
| | - Tonia L Mehlhorn
- Oak Ridge National Laboratory, Environmental Sciences Division, PO Box 2008, MS 6038, Oak Ridge, TN, 37831-6038, USA.
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53
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Jin T, Ren J, Li Y, Bai B, Liu R, Wang Y. Plant growth-promoting effect and genomic analysis of the P. putida LWPZF isolated from C. japonicum rhizosphere. AMB Express 2022; 12:101. [PMID: 35917000 PMCID: PMC9346032 DOI: 10.1186/s13568-022-01445-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 07/28/2022] [Indexed: 11/22/2022] Open
Abstract
Plant growth-promoting rhizobacteria are a type of beneficial bacteria which inhabit in the rhizosphere and possess the abilities to promote plant growth. Pseudomonas putida LWPZF is a plant growth-promoting bacterium isolated from the rhizosphere soil of Cercidiphyllum japonicum. Inoculation treatment with LWPZF could significantly promote the growth of C. japonicum seedlings. P. putida LWPZF has a variety of plant growth-promoting properties, including the ability to solubilize phosphate, synthesize ACC deaminase and IAA. The P. putida LWPZF genome contained a circular chromosome (6,259,530 bp) and a circular plasmid (160,969 bp) with G+C contents of 61.75% and 58.25%, respectively. There were 5632 and 169 predicted protein-coding sequences (CDSs) on the chromosome and the plasmid respectively. Genome sequence analysis revealed lots of genes associated with biosynthesis of IAA, pyoverdine, ACC deaminase, trehalose, volatiles acetoin and 2,3-butanediol, 4-hydroxybenzoate, as well as gluconic acid contributing phosphate solubilization. Additionally, we identified many heavy metal resistance genes, including arsenate, copper, chromate, cobalt-zinc-cadmium, and mercury. These results suggest that P. putida LWPZF shows strong potential in the fields of biofertilizer, biocontrol and heavy metal contamination soil remediation. The data presented in this study will allow us to better understand the mechanisms of plant growth promotion, biocontrol, and anti-heavy metal of P. putida LWPZF.
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Affiliation(s)
- Tingting Jin
- Department of Life Sciences, Changzhi University, Changzhi, 046011, People's Republic of China
| | - Jiahong Ren
- Department of Life Sciences, Changzhi University, Changzhi, 046011, People's Republic of China.
| | - Yunling Li
- Department of Life Sciences, Changzhi University, Changzhi, 046011, People's Republic of China
| | - Bianxia Bai
- Department of Life Sciences, Changzhi University, Changzhi, 046011, People's Republic of China
| | - Ruixiang Liu
- Department of Life Sciences, Changzhi University, Changzhi, 046011, People's Republic of China
| | - Ying Wang
- Department of Life Sciences, Changzhi University, Changzhi, 046011, People's Republic of China
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Kumar Rai R, Shankar Pati R, Islam A, Roy G. Detoxification of organomercurials by thiones and selones: A short review. Inorganica Chim Acta 2022. [DOI: 10.1016/j.ica.2022.120980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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55
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Somayaji A, Dhanjal CR, Lingamsetty R, Vinayagam R, Selvaraj R, Varadavenkatesan T, Govarthanan M. An insight into the mechanisms of homeostasis in extremophiles. Microbiol Res 2022; 263:127115. [PMID: 35868258 DOI: 10.1016/j.micres.2022.127115] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 07/07/2022] [Accepted: 07/07/2022] [Indexed: 01/10/2023]
Abstract
The homeostasis of extremophiles is one that is a diamond hidden in the rough. The way extremophiles adapt to their extreme environments gives a clue into the true extent of what is possible when it comes to life. The discovery of new extremophiles is ever-expanding and an explosion of knowledge surrounding their successful existence in extreme environments is obviously perceived in scientific literature. The present review paper aims to provide a comprehensive view on the different mechanisms governing the extreme adaptations of extremophiles, along with insights and discussions on what the limits of life can possibly be. The membrane adaptations that are vital for survival are discussed in detail. It was found that there are many alterations in the genetic makeup of such extremophiles when compared to their mesophilic counterparts. Apart from the several proteins involved, the significance of chaperones, efflux systems, DNA repair proteins and a host of other enzymes that adapt to maintain functionality, are enlisted, and explained. A deeper understanding of the underlying mechanisms could have a plethora of applications in the industry. There are cases when certain microbes can withstand extreme doses of antibiotics. Such microbes accumulate numerous genetic elements (or plasmids) that possess genes for multiple drug resistance (MDR). A deeper understanding of such mechanisms helps in the development of potential approaches and therapeutic schemes for treating pathogen-mediated outbreaks. An in-depth analysis of the parameters - radiation, pressure, temperature, pH value and metal resistance - are discussed in this review, and the key to survival in these precarious niches is described.
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Affiliation(s)
- Adithi Somayaji
- Department of Biotechnology, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India; Manipal Biomachines, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India
| | - Chetan Roger Dhanjal
- Department of Biotechnology, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India; Manipal Biomachines, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India
| | - Rathnamegha Lingamsetty
- Department of Biotechnology, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India; Manipal Biomachines, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India
| | - Ramesh Vinayagam
- Department of Chemical Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India
| | - Raja Selvaraj
- Department of Chemical Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India
| | - Thivaharan Varadavenkatesan
- Department of Biotechnology, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal 576104, Karnataka, India.
| | - Muthusamy Govarthanan
- Department of Environmental Engineering, Kyungpook National University, Daegu, South Korea; Department of Biomaterials, Saveetha Dental College and Hospital, Saveetha Institute of Medical and Technical Sciences, Chennai 600077, India.
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56
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Floreani F, Acquavita A, Barago N, Klun K, Faganeli J, Covelli S. Gaseous Mercury Exchange from Water–Air Interface in Differently Impacted Freshwater Environments. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19138149. [PMID: 35805807 PMCID: PMC9266016 DOI: 10.3390/ijerph19138149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 06/23/2022] [Accepted: 06/30/2022] [Indexed: 01/27/2023]
Abstract
Gaseous exchanges of mercury (Hg) at the water–air interface in contaminated sites strongly influence its fate in the environment. In this study, diurnal gaseous Hg exchanges were seasonally evaluated by means of a floating flux chamber in two freshwater environments impacted by anthropogenic sources of Hg, specifically historical mining activity (Solkan Reservoir, Slovenia) and the chlor-alkali industry (Torviscosa dockyard, Italy), and in a pristine site, Cavazzo Lake (Italy). The highest fluxes (21.88 ± 11.55 ng m−2 h−1) were observed at Solkan, coupled with high dissolved gaseous mercury (DGM) and dissolved Hg (THgD) concentrations. Conversely, low vertical mixing and saltwater intrusion at Torviscosa limited Hg mobility through the water column, with higher Hg concentrations in the deep layer near the contaminated sediments. Consequently, both DGM and THgD in surface water were generally lower at Torviscosa than at Solkan, resulting in lower fluxes (19.01 ± 12.65 ng m−2 h−1). However, at this site, evasion may also be limited by high atmospheric Hg levels related to dispersion of emissions from the nearby chlor-alkali plant. Surprisingly, comparable fluxes (15.56 ± 12.78 ng m−2 h−1) and Hg levels in water were observed at Cavazzo, suggesting a previously unidentified Hg input (atmospheric depositions or local geology). Overall, at all sites the fluxes were higher in the summer and correlated to incident UV radiation and water temperature due to enhanced photo production and diffusivity of DGM, the concentrations of which roughly followed the same seasonal trend.
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Affiliation(s)
- Federico Floreani
- Department of Mathematics & Geosciences, University of Trieste, Via Weiss 2, 34128 Trieste, Italy; (N.B.); (S.C.)
- Department of Life Sciences, University of Trieste, Via Giorgieri 5, 34127 Trieste, Italy
- Correspondence:
| | - Alessandro Acquavita
- ARPA FVG Regional Agency for Environmental Protection of Friuli Venezia Giulia, Via Cairoli 14, 33057 Palmanova, Italy;
| | - Nicolò Barago
- Department of Mathematics & Geosciences, University of Trieste, Via Weiss 2, 34128 Trieste, Italy; (N.B.); (S.C.)
| | - Katja Klun
- Marine Biology Station, National Institute of Biology, Fornace 41, 6330 Piran, Slovenia; (K.K.); (J.F.)
| | - Jadran Faganeli
- Marine Biology Station, National Institute of Biology, Fornace 41, 6330 Piran, Slovenia; (K.K.); (J.F.)
| | - Stefano Covelli
- Department of Mathematics & Geosciences, University of Trieste, Via Weiss 2, 34128 Trieste, Italy; (N.B.); (S.C.)
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57
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Venturini AM, Gontijo JB, Mandro JA, Paula FS, Yoshiura CA, da França AG, Tsai SM. Genome-resolved metagenomics reveals novel archaeal and bacterial genomes from Amazonian forest and pasture soils. Microb Genom 2022; 8. [PMID: 35894927 PMCID: PMC9455692 DOI: 10.1099/mgen.0.000853] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Amazonian soil microbial communities are known to be affected by the forest-to-pasture conversion, but the identity and metabolic potential of most of their organisms remain poorly characterized. To contribute to the understanding of these communities, here we describe metagenome-assembled genomes (MAGs) recovered from 12 forest and pasture soil metagenomes of the Brazilian Eastern Amazon. We obtained 11 forest and 30 pasture MAGs (≥50% of completeness and ≤10 % of contamination), distributed among two archaeal and 11 bacterial phyla. The taxonomic classification results suggest that most MAGs may represent potential novel microbial taxa. MAGs selected for further evaluation included members of Acidobacteriota, Actinobacteriota, Desulfobacterota_B, Desulfobacterota_F, Dormibacterota, Eremiobacterota, Halobacteriota, Proteobacteria, and Thermoproteota, thus revealing their roles in carbohydrate degradation and mercury detoxification as well as in the sulphur, nitrogen, and methane cycles. A methane-producing Archaea of the genus Methanosarcina was almost exclusively recovered from pasture soils, which can be linked to a sink-to-source shift after the forest-to-pasture conversion. The novel MAGs constitute an important resource to help us unravel the yet-unknown microbial diversity in Amazonian soils and its functional potential and, consequently, the responses of these microorganisms to land-use change.
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Affiliation(s)
- Andressa M Venturini
- Cell and Molecular Biology Laboratory, Center for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, SP, Brazil.,Princeton Institute for International and Regional Studies, Princeton University, Princeton, NJ, USA
| | - Júlia B Gontijo
- Cell and Molecular Biology Laboratory, Center for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, SP, Brazil
| | - Jéssica A Mandro
- Cell and Molecular Biology Laboratory, Center for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, SP, Brazil
| | - Fabiana S Paula
- Cell and Molecular Biology Laboratory, Center for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, SP, Brazil.,Department of Biological Oceanography, Oceanographic Institute, University of São Paulo, São Paulo, SP, Brazil
| | - Caio A Yoshiura
- Cell and Molecular Biology Laboratory, Center for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, SP, Brazil
| | - Aline G da França
- Cell and Molecular Biology Laboratory, Center for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, SP, Brazil
| | - Siu M Tsai
- Cell and Molecular Biology Laboratory, Center for Nuclear Energy in Agriculture, University of São Paulo, Piracicaba, SP, Brazil
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58
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Liu J, Li Y, Duan D, Peng G, Li P, Lei P, Zhong H, Tsui MTK, Pan K. Effects and mechanisms of organic matter regulating the methylmercury dynamics in mangrove sediments. JOURNAL OF HAZARDOUS MATERIALS 2022; 432:128690. [PMID: 35325865 DOI: 10.1016/j.jhazmat.2022.128690] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Revised: 03/09/2022] [Accepted: 03/09/2022] [Indexed: 06/14/2023]
Abstract
Mangrove ecosystems serve as an important carbon sink but also could be a hotspot that produces neurotoxic methylmercury (MeHg). Although many studies have focused on mercury (Hg) contamination in this carbon-rich ecosystem, our understanding of the effects and mechanisms of the organic matter (OM) regulation of MeHg production in mangrove sediments is still limited. Here, we examined the effects of Hg contamination and OM enrichment on MeHg production in anoxic mangrove sediments and identified the major microbial guilds attending this process. The mangrove sediments possessed a high potential for producing MeHg, but this was counterbalanced by its rapid degradation. Sulfate-reducing bacteria (SRB) such as Desulfobacterales, Desulfovibrionales, and Syntrophobacterales were the major methylators. OM diagenesis significantly changed the biogeochemical conditions, accelerating MeHg degradation in the sediments. The enhanced MeHg degradation could be attributed to the abundant sulfide produced during OM decomposition, which could potentially inhibit the Hg methylation by immobilization of inorganic Hg, abiotically degrade MeHg, and favor the non-mer-mediated degradation of MeHg by SRB. Our study provides both geochemical and microbial clues that can partly explain the low MeHg levels widely observed in mangrove sediments.
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Affiliation(s)
- Jingli Liu
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China; Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
| | - Yanping Li
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
| | - Dandan Duan
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China; Ministry of Education Key Laboratory for Ecology of Tropical Islands, College of Life Sciences, Hainan Normal University, Haikou 571158, China
| | - Guogan Peng
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China; Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
| | - Ping Li
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China; Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
| | - Pei Lei
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
| | - Huan Zhong
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
| | - Martin Tsz-Ki Tsui
- School of Life Sciences, State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China
| | - Ke Pan
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China.
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Amin A, Naveed M, Sarwar A, Rasheed S, Saleem HGM, Latif Z, Bechthold A. In vitro and in silico Studies Reveal Bacillus cereus AA-18 as a Potential Candidate for Bioremediation of Mercury-Contaminated Wastewater. Front Microbiol 2022; 13:847806. [PMID: 35733958 PMCID: PMC9207742 DOI: 10.3389/fmicb.2022.847806] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Accepted: 04/25/2022] [Indexed: 11/13/2022] Open
Abstract
Mercury (Hg) pollution is a worldwide problem and increasing day by day due to natural and anthropogenic sources. In this study, mercury-resistant (HgR) bacterial isolates were isolated from industrial wastewater of Ittehad Chemicals Ltd., Kala Shah Kaku, Lahore, Pakistan. Out of 65 bacterial isolates, five isolates were screened out based on showing resistance at 30–40 μg/ml against HgCl2. Selected Hg-resistant bacterial isolates were characterized as Bacillus subtilis AA-16 (OK562835), Bacillus cereus AA-18 (OK562834), Bacillus sp. AA-20 (OK562833), Bacillus paramycoides AA-30 (OK562836), and Bacillus thuringiensis AA-35 (OK562837). B. cereus AA-18 showed promising results in the resistance of HgCl2 (40 μg/ml) due to the presence of merA gene. Scanning electron microscopy (SEM) analysis of immobilized B. cereus AA-18 showed the accumulation Hg on the cell surface. The inoculation of immobilized B. cereus AA-18 remediated 86% Hg of industrial wastewater up to 72 h at large scale (p < 0.05). In silico analysis showed structural determination of MerA protein encoded by merA gene of B. cereus AA-18 (OK562598) using ProtParam, Pfam, ConSurf Server, InterPro, STRING, Jpred4, PSIPRED, I-TASSER, COACH server, TrRosetta, ERRAT, VERIFY3D, Ramachandran plot, and AutoDock Vina (PyRx 8.0). These bioinformatics tools predicted the structural-based functional homology of MerA protein (mercuric reductase) associated with mer operon harboring bacteria involved in Hg-bioremediation system.
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Affiliation(s)
- Aatif Amin
- Department of Microbiology, Faculty of Life Sciences, University of Central Punjab, Lahore, Pakistan
- *Correspondence: Aatif Amin ;
| | - Muhammad Naveed
- Department of Biotechnology, Faculty of Life Sciences, University of Central Punjab, Lahore, Pakistan
| | - Arslan Sarwar
- Department of Microbiology, Faculty of Life Sciences, University of Central Punjab, Lahore, Pakistan
- Department of Plant Pathology, North Dakota State University, Fargo, ND, United States
| | - Sunbul Rasheed
- Department of Microbiology, Faculty of Life Sciences, University of Central Punjab, Lahore, Pakistan
| | - Hafiz Ghulam Murtaza Saleem
- Department of Medical Laboratory Technology, College of Rehabilitation and Allied Health Sciences, Riphah International University, Lahore, Pakistan
| | - Zakia Latif
- School of Biochemistry and Biotechnology, University of the Punjab, Lahore, Pakistan
- Institute of Microbiology and Molecular Genetics, University of the Punjab, Lahore, Pakistan
| | - Andreas Bechthold
- Department of Pharmaceutical Biology and Biotechnology, Institute of Pharmaceutical Sciences, University of Freiburg, Freiburg im Breisgau, Germany
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60
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Nádudvari Á, Cabała J, Marynowski L, Jabłońska M, Dziurowicz M, Malczewski D, Kozielska B, Siupka P, Piotrowska-Seget Z, Simoneit BRT, Szczyrba M. High concentrations of HgS, MeHg and toxic gas emissions in thermally affected waste dumps from hard coal mining in Poland. JOURNAL OF HAZARDOUS MATERIALS 2022; 431:128542. [PMID: 35248960 DOI: 10.1016/j.jhazmat.2022.128542] [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: 11/18/2021] [Revised: 02/13/2022] [Accepted: 02/20/2022] [Indexed: 06/14/2023]
Abstract
This study aims to provide numerous environmental research approaches to understand the formation of mineral and organic mercury compounds in self-heating coal waste dumps of the Upper Silesian Coal Basin (USCB). The results are combined with environmental and health risk assessments. The mineralogy comprised accessory minerals in the fine fraction of thermally affected waste, i.e., Hg sulfides, most likely cinnabar or metacinnabar. Moreover, other metals, e.g., Pb, Zn and Cu, were found as sulfide forms. Apart from Hg, the ICP-ES/MS data confirmed the high content of Mn, Zn, Pb, Hg, Cr and Ba in these wastes. The high concentration of available Hg resulted in elevated MeHg concentrations in the dumps. There were no correlations or trends between MeHg concentrations and elemental Hg, TS, TOC, and pH. Furthermore, we did not detect microbial genes responsible for Hg methylation. The organic compounds identified in waste and emitted gases, such as organic acids, or free methyl radicals, common in such burn environments, could be responsible for the formation of MeHg. The concentration levels of gases, e.g., benzene, formaldehyde, NH3, emitted by the vents, reached or surpassed acceptable levels numerous times. The potential ecological and human health risks of these dumps were moderate to very high due to the significant influence of the high Hg concentrations.
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Affiliation(s)
- Ádám Nádudvari
- University of Silesia in Katowice, Faculty of Natural Sciences, 60 Będzińska Street, 41-200 Sosnowiec, Poland.
| | - Jerzy Cabała
- University of Silesia in Katowice, Faculty of Natural Sciences, 60 Będzińska Street, 41-200 Sosnowiec, Poland
| | - Leszek Marynowski
- University of Silesia in Katowice, Faculty of Natural Sciences, 60 Będzińska Street, 41-200 Sosnowiec, Poland
| | - Mariola Jabłońska
- University of Silesia in Katowice, Faculty of Natural Sciences, 60 Będzińska Street, 41-200 Sosnowiec, Poland
| | - Maria Dziurowicz
- University of Silesia in Katowice, Faculty of Natural Sciences, 60 Będzińska Street, 41-200 Sosnowiec, Poland
| | - Dariusz Malczewski
- University of Silesia in Katowice, Faculty of Natural Sciences, 60 Będzińska Street, 41-200 Sosnowiec, Poland
| | - Barbara Kozielska
- Silesian University of Technology, Faculty of Power and Environmental Engineering, Department of Air Protection, 22B Konarskiego St., 44-100 Gliwice, Poland
| | - Piotr Siupka
- University of Silesia in Katowice, Faculty of Natural Sciences, Institute of Biology, Biotechnology and Environmental Protection, Jagiellonska 28, 40-032 Katowice, Poland
| | - Zofia Piotrowska-Seget
- University of Silesia in Katowice, Faculty of Natural Sciences, Institute of Biology, Biotechnology and Environmental Protection, Jagiellonska 28, 40-032 Katowice, Poland
| | - Bernd R T Simoneit
- Oregon State University, Department of Chemistry, College of Science, Corvallis, OR 97331, USA
| | - Mirosław Szczyrba
- University of Silesia in Katowice, Faculty of Natural Sciences, 60 Będzińska Street, 41-200 Sosnowiec, Poland
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61
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Pande V, Pandey SC, Sati D, Bhatt P, Samant M. Microbial Interventions in Bioremediation of Heavy Metal Contaminants in Agroecosystem. Front Microbiol 2022; 13:824084. [PMID: 35602036 PMCID: PMC9120775 DOI: 10.3389/fmicb.2022.824084] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2021] [Accepted: 03/31/2022] [Indexed: 01/09/2023] Open
Abstract
Soil naturally comprises heavy metals but due to the rapid industrialization and anthropogenic events such as uncontrolled use of agrochemicals their concentration is heightened up to a large extent across the world. Heavy metals are non-biodegradable and persistent in nature thereby disrupting the environment and causing huge health threats to humans. Exploiting microorganisms for the removal of heavy metal is a promising approach to combat these adverse consequences. The microbial remediation is very crucial to prevent the leaching of heavy metal or mobilization into the ecosystem, as well as to make heavy metal extraction simpler. In this scenario, technological breakthroughs in microbes-based heavy metals have pushed bioremediation as a promising alternative to standard approaches. So, to counteract the deleterious effects of these toxic metals, some microorganisms have evolved different mechanisms of detoxification. This review aims to scrutinize the routes that are responsible for the heavy metal(loid)s contamination of agricultural land, provides a vital assessment of microorganism bioremediation capability. We have summarized various processes of heavy metal bioremediation, such as biosorption, bioleaching, biomineralization, biotransformation, and intracellular accumulation, as well as the use of genetically modified microbes and immobilized microbial cells for heavy metal removal.
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Affiliation(s)
- Veni Pande
- Cell and Molecular Biology Laboratory, Department of Zoology (DST-FIST Sponsored), Soban Singh Jeena University Campus, Almora, India
- Department of Biotechnology, Sir J C Bose Technical Campus, Kumaun University, Bhimtal, India
| | - Satish Chandra Pandey
- Cell and Molecular Biology Laboratory, Department of Zoology (DST-FIST Sponsored), Soban Singh Jeena University Campus, Almora, India
| | - Diksha Sati
- Cell and Molecular Biology Laboratory, Department of Zoology (DST-FIST Sponsored), Soban Singh Jeena University Campus, Almora, India
- Department of Zoology, Kumaun University, Nainital, India
| | - Pankaj Bhatt
- Department of Agricultural and Biological Engineering, PurdueUniversity, West Lafayette, IN, United States
| | - Mukesh Samant
- Cell and Molecular Biology Laboratory, Department of Zoology (DST-FIST Sponsored), Soban Singh Jeena University Campus, Almora, India
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62
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Yu RQ, Barkay T. Microbial mercury transformations: Molecules, functions and organisms. ADVANCES IN APPLIED MICROBIOLOGY 2022; 118:31-90. [PMID: 35461663 DOI: 10.1016/bs.aambs.2022.03.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Mercury (Hg) methylation, methylmercury (MeHg) demethylation, and inorganic redox transformations of Hg are microbe-mediating processes that determine the fate and cycling of Hg and MeHg in many environments, and by doing so influence the health of humans and wild life. The discovery of the Hg methylation genes, hgcAB, in the last decade together with advances in high throughput and genome sequencing methods, have resulted in an expanded appreciation of the diversity of Hg methylating microbes. This review aims to describe experimentally confirmed and recently discovered hgcAB gene-carrying Hg methylating microbes; phylogenetic and taxonomic analyses are presented. In addition, the current knowledge on transformation mechanisms, the organisms that carry them out, and the impact of environmental parameters on Hg methylation, MeHg demethylation, and inorganic Hg reduction and oxidation is summarized. This knowledge provides a foundation for future action toward mitigating the impact of environmental Hg pollution.
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Affiliation(s)
- Ri-Qing Yu
- Department of Biology, University of Texas at Tyler, Tyler, TX, United States.
| | - Tamar Barkay
- Department of Biochemistry and Microbiology, Rutgers, The State University of New Jersey, New Brunswick, NJ, United States
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63
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Dissolved Gaseous Mercury (DGM) in the Gulf of Trieste, Northern Adriatic Sea. JOURNAL OF MARINE SCIENCE AND ENGINEERING 2022. [DOI: 10.3390/jmse10050587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Continuous dissolved gaseous mercury (DGM) measurements were performed during the summer months (May to September 2019) in the Gulf of Trieste (northern Adriatic Sea), a well-studied contaminated site due to releases of mercury from the former mercury mine Idrija in Slovenia. Continuous DGM data were regularly checked by the discrete manual method to assure traceability and comparability of the results and used for the calculation of the upward flux of Hg(0) between the water and the air compartment, using the gas exchange model applied in previous studies in the Mediterranean Sea. DGM concentrations measured by continuous and discrete methods showed good agreement, 68.7 and 73.5 ng·m−3, respectively. The diurnal DGM variability examined by sorting the DGM concentrations in 24 1-h intervals was extremely low (68.3–69.2 ng·m−3). Various environmental parameters measured at oceanographic buoy Vida, and the nearby stations were used to determine the relationship between DGM and the individual environmental parameters. The correlation with the oxygen saturation was pronounced during the July high DGM event (R2 = 0.70, p < 0.05), and the gradient between the bottom and surface temperature was correlated with both DGM peaks in June and July (R2 = 0.42 and R2 = 0.43, p < 0.05). Transport from the more polluted northern part of the Gulf was determined as the most probable source of both high DGM events. The computed average annual Hg(0) flux across the water–air interface (5.13 ng·m−2·h−1) was lower than those reported in recent studies. We assume that for an appropriate assessment of the Hg evasion flux and of the temporal DGM variability in such heterogeneously polluted coastal areas, both spatial and temporal coverage are required.
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64
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Liang X, Zhu N, Johs A, Chen H, Pelletier DA, Zhang L, Yin X, Gao Y, Zhao J, Gu B. Mercury Reduction, Uptake, and Species Transformation by Freshwater Alga Chlorella vulgaris under Sunlit and Dark Conditions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:4961-4969. [PMID: 35389633 DOI: 10.1021/acs.est.1c06558] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
As a major entry point of mercury (Hg) to aquatic food webs, algae play an important role in taking up and transforming Hg species in aquatic ecosystems. However, little is known how and to what extent Hg reduction, uptake, and species transformations are mediated by algal cells and their exudates, algal organic matter (AOM), under either sunlit or dark conditions. Here, using Chlorella vulgaris (CV) as one of the most prevalent freshwater model algal species, we show that solar irradiation could enhance the reduction of mercuric Hg(II) to elemental Hg(0) by both CV cells and AOM. AOM reduced more Hg(II) than algal cells themselves due to cell surface adsorption and uptake of Hg(II) inside the cells under solar irradiation. Synchrotron radiation X-ray absorption near-edge spectroscopy (SR-XANES) analyses indicate that sunlight facilitated the transformation of Hg to less bioavailable species, such as β-HgS and Hg-phytochelatins, compared to Hg(Cysteine)2-like species formed in algal cells in the dark. These findings highlight important functional roles and potential mechanisms of algae in Hg reduction and immobilization under varying lighting conditions and how these processes may modulate Hg cycling and bioavailability in the aquatic environment.
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Affiliation(s)
- Xujun Liang
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- School of Resources and Environment Science, Quanzhou Normal University, Quanzhou 362000, China
| | - Nali Zhu
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- School of Environment, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, China
| | - Alexander Johs
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Hongmei Chen
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Dale A Pelletier
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Lijie Zhang
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Xixiang Yin
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Yuxi Gao
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
| | - Jiating Zhao
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Baohua Gu
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Department of Biosystems Engineering and Soil Science, University of Tennessee, Knoxville, Tennessee 37996, United States
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65
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Cossa D, Knoery J, Bănaru D, Harmelin-Vivien M, Sonke JE, Hedgecock IM, Bravo AG, Rosati G, Canu D, Horvat M, Sprovieri F, Pirrone N, Heimbürger-Boavida LE. Mediterranean Mercury Assessment 2022: An Updated Budget, Health Consequences, and Research Perspectives. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:3840-3862. [PMID: 35244390 DOI: 10.1021/acs.est.1c03044] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Mercury (Hg) and especially its methylated species (MeHg) are toxic chemicals that contaminate humans via the consumption of seafood. The most recent UNEP Global Mercury Assessment stressed that Mediterranean populations have higher Hg levels than people elsewhere in Europe. The present Critical Review updates current knowledge on the sources, biogeochemical cycling, and mass balance of Hg in the Mediterranean and identifies perspectives for future research especially in the context of global change. Concentrations of Hg in the Western Mediterranean average 0.86 ± 0.27 pmol L-1 in the upper water layer and 1.02 ± 0.12 pmol L-1 in intermediate and deep waters. In the Eastern Mediterranean, Hg measurements are in the same range but are too few to determine any consistent oceanographical pattern. The Mediterranean waters have a high methylation capacity, with MeHg representing up to 86% of the total Hg, and constitute a source of MeHg for the adjacent North Atlantic Ocean. The highest MeHg concentrations are associated with low oxygen water masses, suggesting a microbiological control on Hg methylation, consistent with the identification of hgcA-like genes in Mediterranean waters. MeHg concentrations are twice as high in the waters of the Western Basin compared to the ultra-oligotrophic Eastern Basin waters. This difference appears to be transferred through the food webs and the Hg content in predators to be ultimately controlled by MeHg concentrations of the waters of their foraging zones. Many Mediterranean top-predatory fish still exceed European Union regulatory Hg thresholds. This emphasizes the necessity of monitoring the exposure of Mediterranean populations, to formulate adequate mitigation strategies and recommendations, without advising against seafood consumption. This review also points out other insufficiencies of knowledge of Hg cycling in the Mediterranean Sea, including temporal variations in air-sea exchange, hydrothermal and cold seep inputs, point sources, submarine groundwater discharge, and exchanges between margins and the open sea. Future assessment of global change impacts under the Minamata Convention Hg policy requires long-term observations and dedicated high-resolution Earth System Models for the Mediterranean region.
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Affiliation(s)
- Daniel Cossa
- Université Grenoble Alpes, ISTerre, CS 40700, 38058 Grenoble Cedex 9, France
| | - Joël Knoery
- Ifremer, Centre Atlantique de Nantes, BP 44311, 44980 Nantes, France
| | - Daniela Bănaru
- Aix Marseille Université, CNRS/INSU, Université de Toulon, IRD, Mediterranean Institute of Oceanography (MIO) UM 110, 13288 Marseille, France
| | - Mireille Harmelin-Vivien
- Aix Marseille Université, CNRS/INSU, Université de Toulon, IRD, Mediterranean Institute of Oceanography (MIO) UM 110, 13288 Marseille, France
| | - Jeroen E Sonke
- Géosciences Environnement Toulouse, CNRS/Observatoire Midi-Pyrénées (OMP)/Université de Toulouse, 31400 Toulouse, France
| | - Ian M Hedgecock
- Istituto sull'inquinamento atmosferico, CNR-IIA, 87036 Rende, Italy
| | | | - Ginevra Rosati
- Istituto Nazionale di Oceanografia e di Geofisca Sperimentale (OGS), 34010 Trieste, Italy
| | - Donata Canu
- Istituto Nazionale di Oceanografia e di Geofisca Sperimentale (OGS), 34010 Trieste, Italy
| | | | | | - Nicola Pirrone
- Istituto sull'inquinamento atmosferico, CNR-IIA, 87036 Rende, Italy
| | - Lars-Eric Heimbürger-Boavida
- Aix Marseille Université, CNRS/INSU, Université de Toulon, IRD, Mediterranean Institute of Oceanography (MIO) UM 110, 13288 Marseille, France
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66
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Al-Ansari MM. Biodetoxification mercury by using a marine bacterium Marinomonas sp. RS3 and its merA gene expression under mercury stress. ENVIRONMENTAL RESEARCH 2022; 205:112452. [PMID: 34856165 DOI: 10.1016/j.envres.2021.112452] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Revised: 11/21/2021] [Accepted: 11/24/2021] [Indexed: 06/13/2023]
Abstract
Mercury (Hg) pollution in water has been a problem for the ecosystem and human health, thus eco-friendly remediation methods are gaining traction around the world. In this study, a bacterial strain designated as RS3 isolated from the Red Sea (Saudi Arabia) has shown tolerance to more than 250 mg/L of Hg2+ on minimum inhibitory studies. The isolate RS3 was identified as Marinomonas sp., (Accession No: OK271312) using 16s rRNA sequencing. Tracing the growth curve for the RS3 showed that maximum growth attained at 72 h and only 10% reduction than the control medium for 50 mg/L HgCl2 supplemented seawater medium, which continued to reduce as 21% to 60 with the increment of HgCl2 from 100 to 350 mg/L. The Hg2+ removal potential of RS3 is observed to be 78% at 50 mg/L HgCl2/72 h, which is significantly altered with the addition of carbon source such as glucose (84.5%) > fructose (79.8%) > control (78%) > citrate (73.4%) > acetate (60.2%) > maltose (54.7%). Box-Behnken design (BBD) well proposed a model with R2 value of 0.8922, which predict a utmost Hg2+ removal of 89.5% by RS2 at favorable conditions (pH-7; NaC 1% and glucose 5%) at 72 h. Mercuric reductase enzyme encoded merA gene expression was found to be high in RS3 isolates cultivated in 100 mg/L of HgCl2 in comparison with other variables. Thus the seawater isolate Marinomonas sp. RS3 expressed a significant tolerance and removal potential towards the Hg2+, which would make it is a noteworthy applicant for effective mercury remediation practices.
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Affiliation(s)
- Mysoon M Al-Ansari
- Department of Botany and Microbiology, College of Science, King Saud University, Riyadh, 11451, Saudi Arabia.
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67
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Cardona GI, Escobar MC, Acosta-González A, Marín P, Marqués S. Highly mercury-resistant strains from different Colombian Amazon ecosystems affected by artisanal gold mining activities. Appl Microbiol Biotechnol 2022; 106:2775-2793. [PMID: 35344092 PMCID: PMC8990959 DOI: 10.1007/s00253-022-11860-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 01/28/2022] [Accepted: 02/27/2022] [Indexed: 02/07/2023]
Abstract
Two sites of the Colombian Amazon region with different levels of human intervention and mercury pollution were selected for the collection of samples of river and lake water, sediments, and associated forest soils. The Tarapacá region, affected mainly by barrage mining, showed low mercury concentrations, whilst in the Taraira region, affected by underground mining, there were several points with high mercury pollution levels. A collection of 72 bacterial and 10 yeast strains with different levels of mercury resistance was isolated and characterized. Most of the highly resistant bacterial strains (MIC > 40 mg L−1 HgCl2) were isolated from soil and sediment samples and belonged to either Pseudomonas (60%) or Bacillus (20%). Most of highly resistant bacterial strains were positive for the presence of the merA gene, suggesting an active mercury resistance mechanism. This was confirmed in the two most resistant strains, Pseudomonas sp. TP30 and Burkholderia contaminans TR100 (MIC = 64 and 71 mg L−1 HgCl2, respectively), which in the presence of increasing mercury concentrations expressed the merA gene at increasing levels, concomitant with a significant mercury reduction activity. Analysis of the MerA sequences present in the different isolates suggested a high gene conservation within the taxonomic groups but also several horizontal gene transfer events between taxonomically distant genera. We also observed a positive correspondence between the presence of the merA gene and the number of antibiotics to which the strains were resistant to. The most resistant strains are good candidates for future applications in the bioremediation of mercury-contaminated sites in the Amazon. Key points • Amazon sediments affected by underground gold mining have higher Hg levels. • Highly Hg-resistant isolates belonged to Pseudomonas and Bacillus genera. • TR100 and TP30 strains showed remediation potential to be used in the Amazon region.
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Affiliation(s)
- Gladys Inés Cardona
- Instituto Amazónico de Investigaciones Científicas SINCHI, 110321, Bogotá, Colombia.
| | - María Camila Escobar
- Instituto Amazónico de Investigaciones Científicas SINCHI, 110321, Bogotá, Colombia
| | | | - Patricia Marín
- Consejo Superior de Investigaciones Científicas, Estación Experimental del Zaidín, Department of Environmental Protection, Granada, Spain
| | - Silvia Marqués
- Consejo Superior de Investigaciones Científicas, Estación Experimental del Zaidín, Department of Environmental Protection, Granada, Spain
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68
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Barkay T, Gu B. Demethylation─The Other Side of the Mercury Methylation Coin: A Critical Review. ACS ENVIRONMENTAL AU 2022; 2:77-97. [PMID: 37101582 PMCID: PMC10114901 DOI: 10.1021/acsenvironau.1c00022] [Citation(s) in RCA: 38] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The public and environmental health consequences of mercury (Hg) methylation have drawn much attention and considerable research to Hg methylation processes and their dynamics in diverse environments and under a multitude of conditions. However, the net methylmercury (MeHg) concentration that accumulates in the environment is equally determined by the rate of MeHg degradation, a complex process mediated by a variety of biotic and abiotic mechanisms, about which our knowledge is limited. Here we review the current knowledge on MeHg degradation and its potential pathways and mechanisms. We describe detoxification by resistant microorganisms that employ the Hg resistance (mer) system to reductively break the carbon-mercury (C-Hg) bond producing methane (CH4) and inorganic mercuric Hg(II), which is then reduced by the mercuric reductase to elemental Hg(0). Very recent research has begun to elucidate a mechanism for the long-recognized mer-independent oxidative demethylation, likely involving some strains of anaerobic bacteria as well as aerobic methane-oxidizing bacteria, i.e., methanotrophs. In addition, photochemical and chemical demethylation processes are described, including the roles of dissolved organic matter (DOM) and free radicals as well as dark abiotic demethylation in the natural environment about which little is currently known. We focus on mechanisms and processes of demethylation and highlight the uncertainties and known effects of environmental factors leading to MeHg degradation. Finally, we suggest future research directions to further elucidate the chemical and biochemical mechanisms of biotic and abiotic demethylation and their significance in controlling net MeHg production in natural ecosystems.
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Affiliation(s)
- Tamar Barkay
- Department of Biochemistry and Microbiology, School of Environmental and Biological Sciences, Rutgers University, New Brunswick, New Jersey 08901, United States
| | - Baohua Gu
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
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69
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Sanz-Sáez I, Pereira-García C, Bravo AG, Trujillo L, Pla i Ferriol M, Capilla M, Sánchez P, Rodríguez Martín-Doimeadios RC, Acinas SG, Sánchez O. Prevalence of Heterotrophic Methylmercury Detoxifying Bacteria across Oceanic Regions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:3452-3461. [PMID: 35245029 PMCID: PMC8928480 DOI: 10.1021/acs.est.1c05635] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 01/29/2022] [Accepted: 01/31/2022] [Indexed: 05/27/2023]
Abstract
Microbial reduction of inorganic divalent mercury (Hg2+) and methylmercury (MeHg) demethylation is performed by the mer operon, specifically by merA and merB genes, respectively, but little is known about the mercury tolerance capacity of marine microorganisms and its prevalence in the ocean. Here, combining culture-dependent analyses with metagenomic and metatranscriptomic data, we show that marine bacteria that encode mer genes are widespread and active in the global ocean. We explored the distribution of these genes in 290 marine heterotrophic bacteria (Alteromonas and Marinobacter spp.) isolated from different oceanographic regions and depths, and assessed their tolerance to diverse concentrations of Hg2+ and MeHg. In particular, the Alteromonas sp. ISS312 strain presented the highest tolerance capacity and a degradation efficiency for MeHg of 98.2% in 24 h. Fragment recruitment analyses of Alteromonas sp. genomes (ISS312 strain and its associated reconstructed metagenome assembled genome MAG-0289) against microbial bathypelagic metagenomes confirm their prevalence in the deep ocean. Moreover, we retrieved 54 merA and 6 merB genes variants related to the Alteromonas sp. ISS312 strain from global metagenomes and metatranscriptomes from Tara Oceans. Our findings highlight the biological reductive MeHg degradation as a relevant pathway of the ocean Hg biogeochemical cycle.
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Affiliation(s)
- Isabel Sanz-Sáez
- Departament
de Biologia Marina i Oceanografia, Institut
de Ciències del Mar, ICM-CSIC, 08003 Barcelona, Catalunya, Spain
| | - Carla Pereira-García
- Departament
de Biologia Marina i Oceanografia, Institut
de Ciències del Mar, ICM-CSIC, 08003 Barcelona, Catalunya, Spain
| | - Andrea G. Bravo
- Departament
de Biologia Marina i Oceanografia, Institut
de Ciències del Mar, ICM-CSIC, 08003 Barcelona, Catalunya, Spain
| | - Laura Trujillo
- Departament
de Biologia Marina i Oceanografia, Institut
de Ciències del Mar, ICM-CSIC, 08003 Barcelona, Catalunya, Spain
| | - Martí Pla i Ferriol
- Departament
de Genètica i Microbiologia, Facultat de Biociències, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
| | - Miguel Capilla
- Research
Group in Environmental Engineering (GI2AM), Department of Chemical
Engineering, University of Valencia, Av. De la Universitat S/N, 46100 Burjassot, Spain
| | - Pablo Sánchez
- Departament
de Biologia Marina i Oceanografia, Institut
de Ciències del Mar, ICM-CSIC, 08003 Barcelona, Catalunya, Spain
| | - Rosa Carmen Rodríguez Martín-Doimeadios
- Environmental
Sciences Institute (ICAM), Department of Analytical Chemistry and
Food Technology, University of Castilla-La
Mancha, Avda. Carlos
III s/n, 45071 Toledo, Spain
| | - Silvia G. Acinas
- Departament
de Biologia Marina i Oceanografia, Institut
de Ciències del Mar, ICM-CSIC, 08003 Barcelona, Catalunya, Spain
| | - Olga Sánchez
- Departament
de Genètica i Microbiologia, Facultat de Biociències, Universitat Autònoma de Barcelona, 08193 Bellaterra, Spain
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70
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Bouchet S, Tessier E, Masbou J, Point D, Lazzaro X, Monperrus M, Guédron S, Acha D, Amouroux D. In Situ Photochemical Transformation of Hg Species and Associated Isotopic Fractionation in the Water Column of High-Altitude Lakes from the Bolivian Altiplano. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:2258-2268. [PMID: 35114086 DOI: 10.1021/acs.est.1c04704] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Photochemical reactions are major pathways for the removal of Hg species from aquatic ecosystems, lowering the concentration of monomethylmercury (MMHg) and its bioaccumulation in foodwebs. Here, we investigated the rates and environmental drivers of MMHg photodegradation and inorganic Hg (IHg) photoreduction in waters of two high-altitude lakes from the Bolivian Altiplano representing meso- to eutrophic conditions. We incubated three contrasting waters in situ at two depths after adding Hg-enriched isotopic species to derive rate constants. We found that transformations mostly occurred in subsurface waters exposed to UV radiation and were mainly modulated by the dissolved organic matter (DOM) level. In parallel, we incubated the same waters after the addition of low concentrations of natural MMHg and followed the stable isotope composition of the remaining Hg species by compound-specific isotope analysis allowing the determination of enrichment factors and mass-independent fractionation (MIF) slopes (Δ199Hg/Δ201Hg) during in situ MMHg photodegradation in natural waters. We found that MIF enrichment factors potentially range from -11 to -19‰ and average -14.3 ± 0.6‰ (1 SE). The MIF slope diverged depending on the DOM level, ranging from 1.24 ± 0.03 to 1.34 ± 0.02 for the low and high DOM waters, respectively, and matched the MMHg MIF slope recorded in fish from the same lake. Our in situ results thus reveal (i) a relatively similar extent of Hg isotopic fractionation during MMHg photodegradation among contrasted natural waters and compared to previous laboratory experiments and (ii) that the MMHg MIF recorded in fish is characteristic for the MMHg bonding environment. They will enable a better assessment of the extent and conditions conducive to MMHg photodegradation in aquatic ecosystems.
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Affiliation(s)
- Sylvain Bouchet
- Universite de Pau et des Pays de l'Adour, E2S/UPPA, CNRS, Institut des sciences analytiques et de physico-chimie pour l'environnement et les matériaux (IPREM), 64000 Pau, France
| | - Emmanuel Tessier
- Universite de Pau et des Pays de l'Adour, E2S/UPPA, CNRS, Institut des sciences analytiques et de physico-chimie pour l'environnement et les matériaux (IPREM), 64000 Pau, France
| | - Jeremy Masbou
- Géosciences Environnement Toulouse (GET), Univ. Paul Sabatier, CNRS, IRD, Observatoire Midi Pyrénées (OMP), 14 avenue Edouard Belin, 31400 Toulouse, France
- Institut Terre et Environnement de Strasbourg (ITES), Université de Strasbourg/EOST/ENGEES, CNRS UMR 7063, 5 rue Descartes, Strasbourg F-67084, France
| | - David Point
- Géosciences Environnement Toulouse (GET), Univ. Paul Sabatier, CNRS, IRD, Observatoire Midi Pyrénées (OMP), 14 avenue Edouard Belin, 31400 Toulouse, France
- Unidad de Calidad Ambiental (UCA) - Instituto de Ecologia - Universidad Mayor de San Andres, Campus Universitario de Cota Cota, Calle 27, 3161 La Paz, Bolivia
| | - Xavier Lazzaro
- Unidad de Calidad Ambiental (UCA) - Instituto de Ecologia - Universidad Mayor de San Andres, Campus Universitario de Cota Cota, Calle 27, 3161 La Paz, Bolivia
- Unité Biologie des Organismes et Ecosystèmes Aquatiques (BOREA), Muséum National d'Histoire Naturelle, Sorbonne Université, Université Caen-Normandie, Université des Antilles, CNRS, IRD. 61 rue Buffon, 75231 Paris CEDEX 5, France
| | - Mathilde Monperrus
- Universite de Pau et des Pays de l'Adour, E2S/UPPA, CNRS, Institut des sciences analytiques et de physico-chimie pour l'environnement et les matériaux (IPREM), 64000 Pau, France
| | - Stéphane Guédron
- Univ. Grenoble Alpes, Univ. Savoie Mont Blanc, CNRS, IRD, IFSTTAR, ISTerre, 38000 Grenoble, France
- Laboratorio de Hidroquímica - Instituto de Investigaciones Químicas - Universidad Mayor de San Andrés, Campus Universitario de Cota-Cota, Casilla, 3161 La Paz, Bolivia
| | - Dario Acha
- Unidad de Calidad Ambiental (UCA) - Instituto de Ecologia - Universidad Mayor de San Andres, Campus Universitario de Cota Cota, Calle 27, 3161 La Paz, Bolivia
| | - David Amouroux
- Universite de Pau et des Pays de l'Adour, E2S/UPPA, CNRS, Institut des sciences analytiques et de physico-chimie pour l'environnement et les matériaux (IPREM), 64000 Pau, France
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Organomercurial lyase (MerB)-mediated demethylation decreases bacterial methylmercury resistance in the absence of mercuric reductase (MerA). Appl Environ Microbiol 2022; 88:e0001022. [PMID: 35138926 DOI: 10.1128/aem.00010-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The mer operon encodes enzymes that transform and detoxify methylmercury (MeHg) and/or inorganic mercury (Hg(II)). Organomercurial lyase (MerB) and mercuric reductase (MerA) can act sequentially to demethylate MeHg to Hg(II) and reduce Hg(II) to volatile elemental mercury (Hg0) that can escape from the cell, conferring resistance to MeHg and Hg(II). Most identified mer operons encode either MerA and MerB in tandem or MerA alone, however, microbial genomes were recently identified that encode only MerB. Yet, the effects of potentially producing intracellular Hg(II) via demethylation of MeHg by MerB, independent of a mechanism to further detoxify or sequester the metal is not well understood. Here, we investigate MeHg biotransformation in Escherichia coli strains engineered to express MerA and MerB, together or separately, and characterize cell viability and Hg detoxification kinetics when these strains are grown in the presence of MeHg. Strains expressing only MerB are capable of demethylating MeHg to Hg(II). Compared to strains that express both MerA and MerB, strains expressing only MerB exhibit a lower minimum inhibitory concentration with MeHg exposure, which parallels a redistribution of Hg from the cell-associated fraction to the culture medium, consistent with cell lysis occurring. The data support a model whereby intracellular production of Hg(II), in the absence of reduction or other forms of demobilization, results in a greater cytotoxicity compared to the parent MeHg compound. Collectively, these results suggest that in the context of MeHg detoxification, MerB must be accompanied by an additional mechanism(s) to reduce, sequester, or re-distribute generated Hg(II). Importance: Mercury is a globally distributed pollutant that poses a risk to wildlife and human health. The toxicity of mercury is influenced largely by microbially mediated biotransformation between its organic (methylmercury) and inorganic (Hg(II) and Hg0) forms. Here we show in a relevant cellular context that the organomercurial lyase (MerB) enzyme is capable of MeHg demethylation without subsequent mercuric reductase (MerA)-mediated reduction of Hg(II). Demethylation of MeHg without subsequent Hg(II) reduction results in a greater cytotoxicity and increased cell lysis. Microbes carrying MerB alone have recently been identified but have yet to be characterized. Our results demonstrate that mer operons encoding MerB but not MerA put the cell at a disadvantage in the context of MeHg exposure, unless subsequent mechanisms of reduction or Hg(II) sequestration exist. These findings may help uncover the existence of alternative mechanisms of Hg(II) detoxification in addition to revealing the drivers of mer operon evolution.
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Tiwari A, Gomez-Alvarez V, Siponen S, Sarekoski A, Hokajärvi AM, Kauppinen A, Torvinen E, Miettinen IT, Pitkänen T. Bacterial Genes Encoding Resistance Against Antibiotics and Metals in Well-Maintained Drinking Water Distribution Systems in Finland. Front Microbiol 2022; 12:803094. [PMID: 35197945 PMCID: PMC8859300 DOI: 10.3389/fmicb.2021.803094] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 12/31/2021] [Indexed: 12/13/2022] Open
Abstract
Information on the co-occurrence of antibiotic resistance genes (ARGs) and metal resistance genes (MRGs) among bacterial communities in drinking water distribution systems (DWDSs) is scarce. This study characterized ARGs and MRGs in five well-maintained DWDSs in Finland. The studied DWDSs had different raw water sources and treatment methods. Two of the waterworks employed artificially recharged groundwater (ARGW) and used no disinfection in the treatment process. The other three waterworks (two surface and one groundwater source) used UV light and chlorine during the treatment process. Ten bulk water samples (two from each DWDS) were collected, and environmental DNA was extracted and then sequenced using the Illumina HiSeq platform for high-throughput shotgun metagenome sequencing. A total of 430 ARGs were characterized among all samples with the highest diversity of ARGs identified from samples collected from non-disinfected DWDSs. Furthermore, non-disinfected DWDSs contained the highest diversity of bacterial communities. However, samples from DWDSs using disinfectants contained over double the ratio of ARG reads to 16S rRNA gene reads and most of the MRG (namely mercury and arsenic resistance genes). The total reads and types of ARGs conferring genes associated with antibiotic groups namely multidrug resistance, and bacitracin, beta-lactam, and aminoglycoside and mercury resistance genes increased in waterworks treating surface water with disinfection. The findings of this study contribute toward a comprehensive understanding of ARGs and MRGs in DWDSs. The occurrence of bacteria carrying antibiotic or metal resistance genes in drinking water causes direct exposure to people, and thus, more systematic investigation is needed to decipher the potential effect of these resistomes on human health.
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Affiliation(s)
- Ananda Tiwari
- Expert Microbiology Unit, Finnish Institute for Health and Welfare, Kuopio, Finland
- Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
- *Correspondence: Ananda Tiwari,
| | - Vicente Gomez-Alvarez
- Office of Research and Development, U.S. Environmental Protection Agency, Cincinnati, OH, United States
| | - Sallamaari Siponen
- Expert Microbiology Unit, Finnish Institute for Health and Welfare, Kuopio, Finland
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
| | - Anniina Sarekoski
- Expert Microbiology Unit, Finnish Institute for Health and Welfare, Kuopio, Finland
| | - Anna-Maria Hokajärvi
- Expert Microbiology Unit, Finnish Institute for Health and Welfare, Kuopio, Finland
| | - Ari Kauppinen
- Expert Microbiology Unit, Finnish Institute for Health and Welfare, Kuopio, Finland
| | - Eila Torvinen
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
| | - Ilkka T. Miettinen
- Expert Microbiology Unit, Finnish Institute for Health and Welfare, Kuopio, Finland
| | - Tarja Pitkänen
- Expert Microbiology Unit, Finnish Institute for Health and Welfare, Kuopio, Finland
- Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland
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73
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Priyadarshanee M, Chatterjee S, Rath S, Dash HR, Das S. Cellular and genetic mechanism of bacterial mercury resistance and their role in biogeochemistry and bioremediation. JOURNAL OF HAZARDOUS MATERIALS 2022; 423:126985. [PMID: 34464861 DOI: 10.1016/j.jhazmat.2021.126985] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Revised: 08/17/2021] [Accepted: 08/19/2021] [Indexed: 06/13/2023]
Abstract
Mercury (Hg) is a highly toxic element that occurs at low concentrations in nature. However, various anthropogenic and natural sources contribute around 5000 to 8000 metric tons of Hg per year, rapidly deteriorating the environmental conditions. Mercury-resistant bacteria that possess the mer operon system have the potential for Hg bioremediation through volatilization from the contaminated milieus. Thus, bacterial mer operon plays a crucial role in Hg biogeochemistry and bioremediation by converting both reactive inorganic and organic forms of Hg to relatively inert, volatile, and monoatomic forms. Both the broad-spectrum and narrow-spectrum bacteria harbor many genes of mer operon with their unique definitive functions. The presence of mer genes or proteins can regulate the fate of Hg in the biogeochemical cycle in the environment. The efficiency of Hg transformation depends upon the nature and diversity of mer genes present in mercury-resistant bacteria. Additionally, the bacterial cellular mechanism of Hg resistance involves reduced Hg uptake, extracellular sequestration, and bioaccumulation. The presence of unique physiological properties in a specific group of mercury-resistant bacteria enhances their bioremediation capabilities. Many advanced biotechnological tools also can improve the bioremediation efficiency of mercury-resistant bacteria to achieve Hg bioremediation.
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Affiliation(s)
- Monika Priyadarshanee
- Laboratory of Environmental Microbiology and Ecology (LEnME), Department of Life Science, National Institute of Technology Rourkela, Rourkela 769 008, Odisha, India
| | - Shreosi Chatterjee
- Laboratory of Environmental Microbiology and Ecology (LEnME), Department of Life Science, National Institute of Technology Rourkela, Rourkela 769 008, Odisha, India
| | - Sonalin Rath
- Laboratory of Environmental Microbiology and Ecology (LEnME), Department of Life Science, National Institute of Technology Rourkela, Rourkela 769 008, Odisha, India
| | - Hirak R Dash
- Laboratory of Environmental Microbiology and Ecology (LEnME), Department of Life Science, National Institute of Technology Rourkela, Rourkela 769 008, Odisha, India
| | - Surajit Das
- Laboratory of Environmental Microbiology and Ecology (LEnME), Department of Life Science, National Institute of Technology Rourkela, Rourkela 769 008, Odisha, India.
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A large transposable element mediates metal resistance in the fungus Paecilomyces variotii. Curr Biol 2022; 32:937-950.e5. [PMID: 35063120 DOI: 10.1016/j.cub.2021.12.048] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 08/11/2021] [Accepted: 12/17/2021] [Indexed: 12/19/2022]
Abstract
The horizontal transfer of large gene clusters by mobile elements is a key driver of prokaryotic adaptation in response to environmental stresses. Eukaryotic microbes face similar stresses; however, a parallel role for mobile elements has not been established. A stress faced by many microorganisms is toxic metal ions in their environment. In fungi, identified mechanisms for protection against metals generally rely on genes that are dispersed within an organism's genome. Here, we discover a large (∼85 kb) region that confers tolerance to five metal/metalloid ions (arsenate, cadmium, copper, lead, and zinc) in the genomes of some, but not all, strains of a fungus, Paecilomyces variotii. We name this region HEPHAESTUS (Hφ) and present evidence that it is mobile within the P. variotii genome with features characteristic of a transposable element. HEPHAESTUS contains the greatest complement of host-beneficial genes carried by a transposable element in eukaryotes, suggesting that eukaryotic transposable elements might play a role analogous to bacteria in the horizontal transfer of large regions of host-beneficial DNA. Genes within HEPHAESTUS responsible for individual metal tolerances include those encoding a P-type ATPase transporter-PcaA-required for cadmium and lead tolerance, a transporter-ZrcA-providing tolerance to zinc, and a multicopper oxidase-McoA-conferring tolerance to copper. In addition, a subregion of Hφ confers tolerance to arsenate. The genome sequences of other fungi in the Eurotiales contain further examples of HEPHAESTUS, suggesting that it is responsible for independently assembling tolerance to a diverse array of ions, including chromium, mercury, and sodium.
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Liu Y, Chen H, Zhu N, Zhang J, Li Y, Xu D, Gao Y, Zhao J. Detection and remediation of mercury contaminated environment by nanotechnology: Progress and challenges. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 293:118557. [PMID: 34813883 DOI: 10.1016/j.envpol.2021.118557] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Revised: 10/19/2021] [Accepted: 11/18/2021] [Indexed: 06/13/2023]
Abstract
Hg pollution is a global concern due to its high ecotoxicity and health risk to human beings. A comprehensive understanding of the fast-developed technology applied in determining and controlling Hg pollution is beneficial for risk assessment and field remediation. Herein, we mainly assembled the recent progress on Hg treatment in the environment by nanotechnology. The advantages and disadvantages of the conventional and nanotechnology-based methods commonly used in water-/soil-Hg remediation were compared and summarized. Specifically, green nanomaterials derived from plant tissues (e.g., nanocellulose) have prominent merits in remediation of Hg contaminated environments, including high efficiency in Hg removal, low cost, environment-friendly, and easily degradable. Based on the theories of Hg biogeochemistry and existed researches, four promising pathways are proposed, 1) developing surface-modified green nanocellulose with high selectivity and affinity towards Hg; 2) designing effective dispersants in preventing nanocellulose from agglomeration in soil; 3) mediating soil properties by adding green nanomaterials-based fertilizers; 4) improving plant-Hg-extract capacity with green nanomaterials addition. Briefly, more efficient and available approaches are still expected to be developed and implemented in the natural environment for Hg remediation.
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Affiliation(s)
- Yonghua Liu
- School of Chemical and Biological Engineering, Taiyuan University of Science and Technology, Taiyuan, 030000, Shanxi, China; CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, CAS-HKU Joint Laboratory of Metallomics on Health and Environment, Institute of High Energy Physics, Chinese Academy of Sciences (CAS), Beijing, 100049, China
| | - Hanqing Chen
- Department of Gastroenterology, Guangzhou Digestive Disease Center, Guangzhou First People's Hospital, School of Medicine, South China University of Technology, Guangzhou, 510180, Guangdong, China
| | - Nali Zhu
- School of Environment, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, 310024, China
| | - Jing Zhang
- School of Chemical and Biological Engineering, Taiyuan University of Science and Technology, Taiyuan, 030000, Shanxi, China
| | - Yufeng Li
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, CAS-HKU Joint Laboratory of Metallomics on Health and Environment, Institute of High Energy Physics, Chinese Academy of Sciences (CAS), Beijing, 100049, China
| | - Diandou Xu
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, CAS-HKU Joint Laboratory of Metallomics on Health and Environment, Institute of High Energy Physics, Chinese Academy of Sciences (CAS), Beijing, 100049, China
| | - Yuxi Gao
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, CAS-HKU Joint Laboratory of Metallomics on Health and Environment, Institute of High Energy Physics, Chinese Academy of Sciences (CAS), Beijing, 100049, China
| | - Jiating Zhao
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, CAS-HKU Joint Laboratory of Metallomics on Health and Environment, Institute of High Energy Physics, Chinese Academy of Sciences (CAS), Beijing, 100049, China.
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76
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Li D, Li X, Tao Y, Yan Z, Ao Y. Deciphering the bacterial microbiome in response to long-term mercury contaminated soil. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2022; 229:113062. [PMID: 34906846 DOI: 10.1016/j.ecoenv.2021.113062] [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: 09/15/2021] [Revised: 11/14/2021] [Accepted: 12/04/2021] [Indexed: 06/14/2023]
Abstract
Hg contaminated soils are of concern due to the toxic effects on soil microbes. Currently, the adaptation of bacterial community to long-term Hg contamination remains largely unknown. Here, we assessed the effects of Hg contaminated soils on the bacterial communities under controlled conditions using 16S rRNA gene amplicon sequencing. The results showed that the bacterial α-diversity and richness were significant positively correlated with total Hg (p < 0.05). Land-use type, pH, EC, TK, and nitrate-N played important roles in shaping the bacterial communities. Long-term Hg-contaminated soils can be divided into three types based on land use types: slag type, farmland type, and mining area type. The dominant phyla include Proteobacteria, Actinobacteriota, Acidobacteriota, Chloroflexi, and Firmicutes. The dominant genera identified were Pseudomonas, Gaiella, Sphingomonas, Bacillus, Arthrobacter, Nocardioides. Network analysis showed that dominant taxa had non-random co-occurrence patterns and module 1 had an important role in responding Hg stress. Keystone genera identified were Bauldia, Phycicoccus, Sphingomonas, Gaiella, Nitrospira. The above results further our understanding of the adaptation of the bacterial community in long-term Hg-contaminated soil. This study has important guiding significance for the use of bacterial consortia to remediate Hg-contaminated soil.
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Affiliation(s)
- Dongbo Li
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Xingjie Li
- College of Life Science & Resources and Environment, Yichun University, Yichun 336000, China
| | - Yu Tao
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Zhenning Yan
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yansong Ao
- School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China.
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77
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Hu H, Li Z, Xi B, Xu Q, Tan W. Responses of bacterial taxonomic attributes to mercury species in rhizosphere paddy soil under natural sulphur-rich biochar amendment. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2022; 229:113058. [PMID: 34890984 DOI: 10.1016/j.ecoenv.2021.113058] [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: 08/27/2021] [Revised: 11/22/2021] [Accepted: 12/03/2021] [Indexed: 06/13/2023]
Abstract
Biochar and sulphur (S) are important factors regulating the level, speciation and transformation of mercury (Hg), leading to alterations in the assemblage of the soil microbial community. However, variations in the taxonomic attributes of the rhizosphere soil bacterial community arising from the Hg speciation in paddy soil, amended with natural S-rich biochar (NSBC) derived from the pyrolysis of S-rich oilseed rape straw, remain unclear. Herein, a rice pot experiment was conducted. Hg-polluted paddy soils were amended with NSBC and low-S biochar (LSBC) to evaluate the role of Hg chemical form affected by NSBC in regulating the taxonomic attributes of rhizosphere soil, including microbial abundance, composition, and ecological clusters within the co-occurrence network of microbial communities. Results showed that microbial abundance was higher in soils with lower Hg levels, and mean increases of 149 observed operational taxonomic units (OTUs) and 238 predicted OTUs (Chao 1) were observed, with a 1 mg kg-1 decrease in the total Hg (T-Hg) content. Among the 13 predictor variables, the T-Hg content was the strongest and most consistent predictor of the bacterial taxonomic attributes. This finding may be attributed to the fact that the drastic reduction in T-Hg and Hg bioavailability induced by NSBC results in the decrease of Hg stress on the soil microbiome. Moreover, NSBC amendment shifted the ecological clusters toward the amelioration of Hg pollution.
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Affiliation(s)
- Hualing Hu
- School of Environmental Science & Engineering, Tianjin University, Tianjin 300350, China; State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Zhonghong Li
- State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Beidou Xi
- School of Environmental Science & Engineering, Tianjin University, Tianjin 300350, China; State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Qigong Xu
- State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
| | - Wenbing Tan
- State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
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78
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Sun C, Fang YC, Li H, Chen J, Ye YL, Ni LF, Xu L, Han BN, Wu M, Wang CS, Xu XW. Complete genome sequence of marine Roseobacter lineage member Monaibacterium sp. ALG8 with six plasmids isolated from seawater around brown algae. Mar Genomics 2021; 60:100878. [PMID: 34006489 DOI: 10.1016/j.margen.2021.100878] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 05/09/2021] [Accepted: 05/10/2021] [Indexed: 11/26/2022]
Abstract
Monaibacterium sp. ALG8 (=MCCC 1 K04733) was isolated from seawater around brown algae. The genome of Monaibacterium sp. ALG8 was sequenced, one circular 3,036,380 bp chromosome and six circular plasmids ranging from 12,229 to 151,263 bp were found after assembly. The results of genomic annotation showed that Monaibacterium sp. ALG8 lacks the ability to degrade alginate, indicating its ecological role may not be directly related to the degradation of brown algae. The comparison of genomic features in the plasmids showed that almost all of these plasmids, except pALG4, were horizontally recruited from donors, not ancestors. Based on predicted functions, the existence of plasmids may provide strain ALG8 with advantages including nitrate reduction, tolerance of osmotic stress via glycine betaine, resistance to heavy metal stress such as mercury and cobalt, degradation of benzoate metabolites such as p-cumate, transformation of the swim-or-stick lifestyle and improvement of the immune system with two CRISPR-Cas systems. This study provides evidence for the carbon metabolic patterns of Monaibacterium sp. ALG8 and predicts the functions and donors of six plasmids in this strain, broadening our understanding of the ecological roles of bacteria in the environment around brown algae and the functions and evolutionary patterns of plasmids in marine Roseobacter lineage members.
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Affiliation(s)
- Cong Sun
- Key Laboratory of Marine Ecosystem Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou 310012, PR China; College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou 310018, PR China
| | - Yuan-Chun Fang
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou 310018, PR China
| | - Hao Li
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou 310018, PR China
| | - Jie Chen
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou 310018, PR China
| | - Yong-Lian Ye
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou 310018, PR China
| | - Ling-Fang Ni
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou 310018, PR China
| | - Lin Xu
- Key Laboratory of Marine Ecosystem Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou 310012, PR China; College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou 310018, PR China
| | - Bing-Nan Han
- College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou 310018, PR China
| | - Min Wu
- College of Life Sciences, Zhejiang University, Hangzhou 310058, PR China
| | - Chun-Sheng Wang
- Key Laboratory of Marine Ecosystem Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou 310012, PR China
| | - Xue-Wei Xu
- Key Laboratory of Marine Ecosystem Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou 310012, PR China.
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79
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Transcriptomic evidence for versatile metabolic activities of mercury cycling microorganisms in brackish microbial mats. NPJ Biofilms Microbiomes 2021; 7:83. [PMID: 34799579 PMCID: PMC8605020 DOI: 10.1038/s41522-021-00255-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 10/22/2021] [Indexed: 01/29/2023] Open
Abstract
Methylmercury, biomagnifying through food chains, is highly toxic for aquatic life. Its production and degradation are largely driven by microbial transformations; however, diversity and metabolic activity of mercury transformers, resulting in methylmercury concentrations in environments, remain poorly understood. Microbial mats are thick biofilms where oxic and anoxic metabolisms cooccur, providing opportunities to investigate the complexity of the microbial mercury transformations over contrasted redox conditions. Here, we conducted a genome-resolved metagenomic and metatranscriptomic analysis to identify putative activity of mercury reducers, methylators and demethylators in microbial mats strongly contaminated by mercury. Our transcriptomic results revealed the major role of rare microorganisms in mercury cycling. Mercury methylators, mainly related to Desulfobacterota, expressed a large panel of metabolic activities in sulfur, iron, nitrogen, and halogen compound transformations, extending known activities of mercury methylators under suboxic to anoxic conditions. Methylmercury detoxification processes were dissociated in the microbial mats with methylmercury cleavage being carried out by sulfide-oxidizing Thiotrichaceae and Rhodobacteraceae populations, whereas mercury reducers included members of the Verrucomicrobia, Bacteroidetes, Gammaproteobacteria, and different populations of Rhodobacteraceae. However most of the mercury reduction was potentially carried out anaerobically by sulfur- and iron-reducing Desulfuromonadaceae, revising our understanding of mercury transformers ecophysiology.
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80
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Characterization of a mercury tolerant strain of Staphylococcus arlettae from Darjeeling hills with an account of its antibiotic resistance pattern and metabolome. Arch Microbiol 2021; 203:5745-5754. [PMID: 34494142 DOI: 10.1007/s00203-021-02563-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Revised: 08/25/2021] [Accepted: 08/30/2021] [Indexed: 12/29/2022]
Abstract
Mercury (Hg) is a ubiquitous heavy metal grouped with the top ten most toxic pollutants affecting both human and environmental health. Consequently, mercury contamination due to anthropogenic interference has become a rising global concern. The bacterial strain MTD10A was isolated from soil samples collected over the Darjeeling hills. Heavy metal tolerance study conducted exhibited considerable tolerance to mercury by this bacterial isolate at unprecedented concentrations of up to 0.1 mg/mL of HgCl2. Biochemical characterization and molecular identification via 16S rRNA sequencing identified this highly tolerant bacteria as a strain of a Coagulase Negative Staphylococcus arlettae. This study also maps the resistance pattern of MTD10A against clinically relevant antibiotics and contains a broad assessment of the metabolomic profile of the bacteria achieved via GC-MS. Tolerance of MTD10A to such excessive levels of mercury shown in our study suggests the possibility of a promising candidate for bioremediation in heavily mercury contaminated areas.
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81
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Arib C, Bouchemal N, Barile M, Paleni D, Djaker N, Dupont N, Spadavecchia J. Flavin-adenine-dinucleotide gold complex nanoparticles: chemical modeling design, physico-chemical assessment and perspectives in nanomedicine. NANOSCALE ADVANCES 2021; 3:6144-6156. [PMID: 36133939 PMCID: PMC9418941 DOI: 10.1039/d1na00444a] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 08/09/2021] [Indexed: 05/10/2023]
Abstract
Flavoproteins play an important role in the regulatory process of cell life, and they are involved in several redox reactions that regulate the metabolism of carbohydrates, amino acids, and lipids. The development of effective drug delivery systems is one of the major challenges in the fight against cancer. This study involves a nanomedicine pathway to encapsulate the cofactor flavin adenine dinucleotide (FAD) using polymeric gold nanoparticles (PEG-AuNPs) through two chemical methods of functionalization (chelation (IN); carbodiimide chemistry (ON)). These hybrid gold nanoparticles and their precursors were characterized by analytical techniques (Raman, UV-Vis, and H1-NMR spectroscopy and transmission electron microscopy (TEM)) which confirmed the grafting of the cofactor agent. The results of the computational studies (Density Functional Theory (DFT)) were in agreement with the experimental observations. We also monitored the interaction of our hybrid nanoparticle systems with small aptamers (APT) in order to validate the hypotheses on the biomolecular mechanisms and also investigate their biological efficiency on pancreatic cancer cells (MIAPaCa-2 cells).
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Affiliation(s)
- Celia Arib
- CNRS, UMR 7244, CSPBAT, Laboratoire de Chimie, Structures et Propriétés de Biomatériaux et d'Agents Thérapeutiques Université Paris 13, Sorbonne Paris Nord, 1 Rue Chablis 93000 Bobigny France
| | - Nadia Bouchemal
- CNRS, UMR 7244, CSPBAT, Laboratoire de Chimie, Structures et Propriétés de Biomatériaux et d'Agents Thérapeutiques Université Paris 13, Sorbonne Paris Nord, 1 Rue Chablis 93000 Bobigny France
| | - Maria Barile
- Dept. of Biosciences, Biotechnology and Biopharmaceutics, University of Bari "Aldo Moro" Via Orabona 470126 Bari Italy
| | | | - Nadia Djaker
- CNRS, UMR 7244, CSPBAT, Laboratoire de Chimie, Structures et Propriétés de Biomatériaux et d'Agents Thérapeutiques Université Paris 13, Sorbonne Paris Nord, 1 Rue Chablis 93000 Bobigny France
| | - Nathalie Dupont
- CNRS, UMR 7244, CSPBAT, Laboratoire de Chimie, Structures et Propriétés de Biomatériaux et d'Agents Thérapeutiques Université Paris 13, Sorbonne Paris Nord, 1 Rue Chablis 93000 Bobigny France
| | - Jolanda Spadavecchia
- CNRS, UMR 7244, CSPBAT, Laboratoire de Chimie, Structures et Propriétés de Biomatériaux et d'Agents Thérapeutiques Université Paris 13, Sorbonne Paris Nord, 1 Rue Chablis 93000 Bobigny France
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82
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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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83
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Singh K, Sharmila P, Kumar PA, Pardha-Saradhi P. Successful expression of the synthetic merBps gene in tobacco. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2021; 167:874-883. [PMID: 34537577 DOI: 10.1016/j.plaphy.2021.09.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 09/10/2021] [Accepted: 09/12/2021] [Indexed: 06/13/2023]
Abstract
Organomercury is the most toxic biomagnifiable state of mercury, and to date, no natural organomercurial detoxification mechanism is encountered in plants. Bacterial merB gene encoding organomercury lyase show low expression in transgenic plants. For ideal expression, a synthetic merBps gene possessing143 out of 213 codons discrete from native merB gene from Escherichia. coli was fabricated based on codon usage in tobacco. Through Agrobacterium-mediated transformation, the merBps gene got successfully integrated into tobacco. Of several putative merBps transformants selected with 200 μg ml-1 kanamycin, only ∼45% were PCR positive for both nptII and merBps genes. Healthy and vigorously growing shoots of few PCR-positive putative transgenic lines were multiplied and rooted. After transplantation and acclimatization, the resultant plants flowered and fruited in pots. Southern analysis revealed the presence of a single copy of the merBps gene in four lines. RT-PCR and Western investigations established successful transcription and translation of the merBps gene in these transgenic lines, respectively. Fabrication of fully functional organomercury lyase in merBps transgenic lines was established based on the potential of their (i) seeds to germinate; (ii) shoots to grow and multiply; and (iii) leaf disc to remain green, even in the presence of 4 nmole ml-1 phenylmercuryacetate (PMA) while the wild type was susceptible to even 1 nmole ml-1 PMA. These findings confirmed that the synthetic merBps gene could be effectively expressed in plants and exploited for remediation of organomercurial contaminated sites.
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Affiliation(s)
- Kavita Singh
- Department of Environmental Studies, University of Delhi, Delhi, 110007, India; National Research Center on Plant Biotechnology, Indian Agricultural Research Institute, NewDelhi, 110012, India
| | - Peddisetty Sharmila
- Department of Environmental Studies, University of Delhi, Delhi, 110007, India
| | - P Ananda Kumar
- National Research Center on Plant Biotechnology, Indian Agricultural Research Institute, NewDelhi, 110012, India
| | - P Pardha-Saradhi
- Department of Environmental Studies, University of Delhi, Delhi, 110007, India.
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84
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Bowman KL, Lamborg CH, Agather AM, Hammerschmidt CR. The role of plastic debris in the biogeochemical cycle of mercury in Lake Erie and San Francisco Bay. MARINE POLLUTION BULLETIN 2021; 171:112768. [PMID: 34343756 DOI: 10.1016/j.marpolbul.2021.112768] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 07/21/2021] [Accepted: 07/22/2021] [Indexed: 06/13/2023]
Abstract
The accumulation of plastic debris that concentrates hydrophobic compounds and microbial communities creates the potential for altered aquatic biogeochemical cycles. This study investigated the role of plastic debris in the biogeochemical cycling of mercury in surface waters of the San Francisco Bay, Sacramento River, Lake Erie, and in coastal seawater. Total mercury and monomethylmercury were measured on plastic debris from all study sites. Plastic-bound microbial communities from Lake Erie and San Francisco Bay contained several lineages of known mercury methylating microbes, however the hgcAB gene cluster was not detected using polymerase chain reaction. These plastic-bound microbial communities also contained species that possess the mer operon, and merA genes were detected using polymerase chain reaction. In coastal seawater incubations, rapid mercury methylation percentages were greater in the presence of microplastics and demethylation percentages decreased as monomethylmercury additions adsorbed to microplastics. These findings suggest that plastic pollution has the potential to alter the biogeochemical cycling of mercury in aquatic ecosystems.
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Affiliation(s)
- Katlin L Bowman
- Department of Ocean Sciences, University of California Santa Cruz, Santa Cruz, CA 95064, United States of America; Moss Landing Marine Laboratories, Moss Landing, CA 95039, United States of America.
| | - Carl H Lamborg
- Department of Ocean Sciences, University of California Santa Cruz, Santa Cruz, CA 95064, United States of America
| | - Alison M Agather
- Department of Earth & Environmental Sciences, Wright State University, Dayton, OH 45435, United States of America; Cherokee Nation Strategic Programs, Arlington, VA 22202, United States of America
| | - Chad R Hammerschmidt
- Department of Earth & Environmental Sciences, Wright State University, Dayton, OH 45435, United States of America
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85
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Rani L, Srivastav AL, Kaushal J. Bioremediation: An effective approach of mercury removal from the aqueous solutions. CHEMOSPHERE 2021; 280:130654. [PMID: 34162069 DOI: 10.1016/j.chemosphere.2021.130654] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 04/03/2021] [Accepted: 04/21/2021] [Indexed: 06/13/2023]
Abstract
Mercury (Hg(II)) is the 16th rarest element present in the earth's crust. Due to rapid industrialization and urban expansions, the mercury concentration has been elevated in the environment. Hg(II) contamination in the aqueous environment has become a great challenge for human beings. The main source of Hg(II) in the aqueous phase is untreated effluent industries (such as the paper industry). Hg(II) is non-biodegradable in nature and even its trace amount in an aqueous environment can pose chronic threats among the humans (damage to the central nervous system, respiratory system, and cardiovascular system, mutation of DNA), animals, and aquatic creatures. Therefore, the removal of mercury from aqueous solutions is an urgent need of the modern era. The conventional techniques such as ion exchange, precipitation, membrane filtrations are costly and also generate byproducts in the environment. Bioremediation is a sustainable, environmentally sound, and cost-effective technique to remove Hg(II) from the aqueous solutions. In this process, naturally occurring microorganisms are utilized to remove the Hg(II) from the aqueous solutions. Lentinus edodes, U. lactuca, and Typha domingensis are found to have great potential to remove mercury from water ranged from ~100 mg g-1 to 337 mg g-1.
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Affiliation(s)
- Lata Rani
- Centre for Water Sciences, Chitkara University Institute of Engineering & Technology, Chitkara University, Punjab, 140 417, India; School of Basic Sciences, Chitkara University, Himachal Pradesh, 174 103, India
| | - Arun Lal Srivastav
- Chitkara University School of Engineering and Technology, Chitkara University, Himachal Pradesh, 174 103, India.
| | - Jyotsna Kaushal
- Centre for Water Sciences, Chitkara University Institute of Engineering & Technology, Chitkara University, Punjab, 140 417, India
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86
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Amin A, Naveed M, Munawar U, Sarwar A, Latif Z. Characterization of Mercury-Resistant Rhizobacteria for Plant Growth Promotion: An In Vitro and In Silico Approach. Curr Microbiol 2021; 78:3968-3979. [PMID: 34550433 DOI: 10.1007/s00284-021-02660-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Accepted: 09/08/2021] [Indexed: 10/20/2022]
Abstract
In this study, a total 30 rhizobacterial isolates were screened out based on resistance against different concentrations of mercuric chloride (HgCl2), growth on nitrogen-free mannitol (NFM) and production of indole-3-acetic acid (IAA). The biochemical and plant growth promoting characterization of selected isolates was performed by different biochemical tests. Out of 30, six isolates, UM-3, AZ-5, UM-7, UM-11, UM-26, and UM-28 showed resistance at 30 µg/ml HgCl2, pronounced growth on NFM and high production of IAA as 18.6, 16.7, 16, 18.7, 14, and 16 µg/ml, respectively (P < 0.05). The 16S rDNA ribotyping and phylogenetic analysis of selected bacterial isolates were performed and characterized as Exiguobacterium sp. UM-3 (KJ736011), Bacillus thuringiensis AZ-5 (KJ675627), Bacillus subtilis UM-7 (KJ736013), Enterobacter cloacae UM-11 (KJ736014), Pseudomonas aeruginosa UM-26 (KJ736016), P. aeruginosa UM-28 (KJ736017) and Bacillus pumilus UM-16 (KJ736015) used as negative control. B. thuringiensis AZ-5 showed high resistance against 30 µg/ml of HgCl2 due to the presence of merB gene. The structural determination of MerB protein was carried out using bioinformatics tools, i.e., Protparam, Pfam, InterProScan, STRING, Jpred4, PSIPRED, I-TASSER, COACH server and ERRAT. These tools predicted the structural based functional homology of MerB protein (organomercuric lyase) in association with MerA (mercuric reductase) in bacterial Hg-detoxification system.
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Affiliation(s)
- Aatif Amin
- Department of Microbiology, Faculty of Life Sciences, University of Central Punjab, Lahore, 54000, Pakistan.
| | - Muhammad Naveed
- Department of Biotechnology, Faculty of Life Sciences, University of Central Punjab, Lahore, 54000, Pakistan
| | - Umair Munawar
- Institute of Microbiology and Molecular Genetics, University of the Punjab, Lahore, 54590, Pakistan
| | - Arslan Sarwar
- Department of Microbiology, Faculty of Life Sciences, University of Central Punjab, Lahore, 54000, Pakistan
| | - Zakia Latif
- Institute of Microbiology and Molecular Genetics, University of the Punjab, Lahore, 54590, Pakistan
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87
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Öztürk B, Werner J, Meier-Kolthoff JP, Bunk B, Spröer C, Springael D. Comparative Genomics Suggests Mechanisms of Genetic Adaptation toward the Catabolism of the Phenylurea Herbicide Linuron in Variovorax. Genome Biol Evol 2021; 12:827-841. [PMID: 32359160 PMCID: PMC7313664 DOI: 10.1093/gbe/evaa085] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/20/2020] [Indexed: 01/07/2023] Open
Abstract
Biodegradation of the phenylurea herbicide linuron appears a specialization within a specific clade of the Variovorax genus. The linuron catabolic ability is likely acquired by horizontal gene transfer but the mechanisms involved are not known. The full-genome sequences of six linuron-degrading Variovorax strains isolated from geographically distant locations were analyzed to acquire insight into the mechanisms of genetic adaptation toward linuron metabolism. Whole-genome sequence analysis confirmed the phylogenetic position of the linuron degraders in a separate clade within Variovorax and indicated that they unlikely originate from a common ancestral linuron degrader. The linuron degraders differentiated from Variovorax strains that do not degrade linuron by the presence of multiple plasmids of 20–839 kb, including plasmids of unknown plasmid groups. The linuron catabolic gene clusters showed 1) high conservation and synteny and 2) strain-dependent distribution among the different plasmids. Most of them were bordered by IS1071 elements forming composite transposon structures, often in a multimeric array configuration, appointing IS1071 as a key element in the recruitment of linuron catabolic genes in Variovorax. Most of the strains carried at least one (catabolic) broad host range plasmid that might have been a second instrument for catabolic gene acquisition. We conclude that clade 1 Variovorax strains, despite their different geographical origin, made use of a limited genetic repertoire regarding both catabolic functions and vehicles to acquire linuron biodegradation.
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Affiliation(s)
- Başak Öztürk
- Junior Research Group Microbial Biotechnology, Leibniz Institute DSMZ, German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany.,Division of Soil and Water Management, KU Leuven, Belgium
| | - Johannes Werner
- Department of Biological Oceanography, Leibniz Institute for Baltic Sea Research, Rostock, Germany
| | - Jan P Meier-Kolthoff
- Department Bioinformatics and Databases, Leibniz Institute DSMZ, German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Boyke Bunk
- Department Bioinformatics and Databases, Leibniz Institute DSMZ, German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Cathrin Spröer
- Department Bioinformatics and Databases, Leibniz Institute DSMZ, German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Dirk Springael
- Division of Soil and Water Management, KU Leuven, Belgium
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88
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Christakis CA, Barkay T, Boyd ES. Expanded Diversity and Phylogeny of mer Genes Broadens Mercury Resistance Paradigms and Reveals an Origin for MerA Among Thermophilic Archaea. Front Microbiol 2021; 12:682605. [PMID: 34248899 PMCID: PMC8261052 DOI: 10.3389/fmicb.2021.682605] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 05/28/2021] [Indexed: 11/13/2022] Open
Abstract
Mercury (Hg) is a highly toxic element due to its high affinity for protein sulfhydryl groups, which upon binding, can destabilize protein structure and decrease enzyme activity. Prokaryotes have evolved enzymatic mechanisms to detoxify inorganic Hg and organic Hg (e.g., MeHg) through the activities of mercuric reductase (MerA) and organomercury lyase (MerB), respectively. Here, the taxonomic distribution and evolution of MerAB was examined in 84,032 archaeal and bacterial genomes, metagenome assembled genomes, and single-cell genomes. Homologs of MerA and MerB were identified in 7.8 and 2.1% percent of genomes, respectively. MerA was identified in the genomes of 10 archaeal and 28 bacterial phyla previously unknown to code for this functionality. Likewise, MerB was identified in 2 archaeal and 11 bacterial phyla previously unknown to encode this functionality. Surprisingly, homologs of MerB were identified in a number of genomes (∼50% of all MerB-encoding genomes) that did not encode MerA, suggesting alternative mechanisms to detoxify Hg(II) once it is generated in the cytoplasm. Phylogenetic reconstruction of MerA place its origin in thermophilic Thermoprotei (Crenarchaeota), consistent with high levels of Hg(II) in geothermal environments, the natural habitat of this archaeal class. MerB appears to have been recruited to the mer operon relatively recently and likely among a mesophilic ancestor of Euryarchaeota and Thaumarchaeota. This is consistent with the functional dependence of MerB on MerA and the widespread distribution of mesophilic microorganisms that methylate Hg(II) at lower temperature. Collectively, these results expand the taxonomic and ecological distribution of mer-encoded functionalities, and suggest that selection for Hg(II) and MeHg detoxification is dependent not only on the availability and type of mercury compounds in the environment but also the physiological potential of the microbes who inhabit these environments. The expanded diversity and environmental distribution of MerAB identify new targets to prioritize for future research.
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Affiliation(s)
- Christos A. Christakis
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, United States
| | - Tamar Barkay
- Department of Biochemistry and Microbiology, Rutgers, The State University of New Jersey, New Brunswick, NJ, United States
| | - Eric S. Boyd
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, United States
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89
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Rothenberg SE, Sweitzer DN, Rackerby BR, Couch CE, Cohen LA, Broughton HM, Steingass SM, Beechler BR. Fecal Methylmercury Correlates With Gut Microbiota Taxa in Pacific Walruses ( Odobenus rosmarus divergens). Front Microbiol 2021; 12:648685. [PMID: 34177830 PMCID: PMC8220164 DOI: 10.3389/fmicb.2021.648685] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Accepted: 04/30/2021] [Indexed: 01/04/2023] Open
Abstract
OBJECTIVES Methylmercury metabolism was investigated in Pacific walruses (Odobenus rosmarus divergens) from St. Lawrence Island, Alaska, United States. METHODS Total mercury and methylmercury concentrations were measured in fecal samples and paired colon samples (n = 16 walruses). Gut microbiota composition and diversity were determined using 16S rRNA gene sequencing. Associations between fecal and colon mercury and the 24 most prevalent gut microbiota taxa were investigated using linear models. RESULTS In fecal samples, the median values for total mercury, methylmercury, and %methylmercury (of total mercury) were 200 ng/g, 4.7 ng/g, and 2.5%, respectively, while in colon samples, the median values for the same parameters were 28 ng/g, 7.8 ng/g, and 26%, respectively. In fecal samples, methylmercury was negatively correlated with one Bacteroides genus, while members of the Oscillospirales order were positively correlated with both methylmercury and %methylmercury (of total mercury). In colon samples, %methylmercury (of total mercury) was negatively correlated with members of two genera, Romboutsia and Paeniclostridium. CONCLUSIONS Median %methylmercury (of total mercury) was 10 times higher in the colon compared to the fecal samples, suggesting that methylmercury was able to pass through the colon into systemic circulation. Fecal total mercury and/or methylmercury concentrations in walruses were comparable to some human studies despite differences in seafood consumption rates, suggesting that walruses excreted less mercury. There are no members (at this time) of the Oscillospirales order which are known to contain the genes to methylate mercury, suggesting the source of methylmercury in the gut was from diet and not in vivo methylation.
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Affiliation(s)
- Sarah E. Rothenberg
- College of Public Health and Human Sciences, Oregon State University, Corvallis, OR, United States
| | - Danielle N. Sweitzer
- Carlson College of Veterinary Medicine, Oregon State University, Corvallis, OR, United States
| | - Bryna R. Rackerby
- Department of Food Science and Technology, College of Agricultural Sciences, Oregon State University, Corvallis, OR, United States
| | - Claire E. Couch
- Department of Fisheries, Wildlife, and Conservation Sciences, College of Agricultural Sciences, Oregon State University, Corvallis, OR, United States
| | - Lesley A. Cohen
- Carlson College of Veterinary Medicine, Oregon State University, Corvallis, OR, United States
| | - Heather M. Broughton
- Department of Biology, Oregon State University-Cascades, Bend, OR, United States
| | - Sheanna M. Steingass
- Department of Fisheries, Wildlife, and Conservation Sciences, Marine Mammal Institute, Oregon State University, Corvallis, OR, United States
| | - Brianna R. Beechler
- Carlson College of Veterinary Medicine, Oregon State University, Corvallis, OR, United States
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90
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Xu R, Sun X, Häggblom MM, Dong Y, Zhang M, Yang Z, Xiao E, Xiao T, Gao P, Li B, Sun W. Metabolic potentials of members of the class Acidobacteriia in metal-contaminated soils revealed by metagenomic analysis. Environ Microbiol 2021; 24:803-818. [PMID: 34081382 DOI: 10.1111/1462-2920.15612] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Revised: 05/18/2021] [Accepted: 05/23/2021] [Indexed: 01/09/2023]
Abstract
The relative abundance of Acidobacteriia correlated positively with the concentrations of arsenic (As), mercury (Hg), chromium (Cr), copper (Cu) and other metals, suggesting their adaptation of the metal-rich environments. Metagenomic binning reconstructed 29 high-quality metagenome-assembled genomes (MAGs) associated with Acidobacteriia, providing an opportunity to study their metabolic potentials. These MAGs contained genes to transform As, Hg and Cr through oxidation, reduction, efflux and demethylation, suggesting the potential of Acidobacteriia to transform such metal(loid)s. Additionally, genes associated with alleviation of acidic and metal stress were also detected in these MAGs. Acidobacteriia may have the capabilities to resist or transform metal(loid)s in acidic metal-contaminated sites. Moreover, these genes encoding metal transformation could be also identified in the Acidobacteriia-associated MAGs from five additional metal-contaminated sites across Southwest China, as well as Acidobacteriia-associated reference genomes from the NCBI database, suggesting that the capability of metal transformation may be widespread among Acidobacteriia members. This discovery provides an understanding of metabolic potentials of the Acidobacteriia in acidic metal-rich sites.
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Affiliation(s)
- Rui Xu
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou, 510650, China.,Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
| | - Xiaoxu Sun
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou, 510650, China.,Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
| | - Max M Häggblom
- Department of Biochemistry and Microbiology, Rutgers, The State University of New Jersey, New Brunswick, New Jersey, USA
| | - Yiran Dong
- School of Environmental Studies, China University of Geosciences (Wuhan), Wuhan, 430074, China
| | - Miaomiao Zhang
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou, 510650, China.,Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
| | - Zhaohui Yang
- College of Environmental Science and Engineering, Hunan University, Changsha, 410082, China
| | - Enzong Xiao
- Key Laboratory of Water Quality and Conservation in the Pearl River Delta, Ministry of Education, School of Environmental Science and Engineering, Guangzhou University, Guangzhou, 510006, China
| | - Tangfu Xiao
- Key Laboratory of Water Quality and Conservation in the Pearl River Delta, Ministry of Education, School of Environmental Science and Engineering, Guangzhou University, Guangzhou, 510006, China
| | - Pin Gao
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou, 510650, China.,Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
| | - Baoqin Li
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou, 510650, China.,Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
| | - Weimin Sun
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou, 510650, China.,Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China.,School of Environment, Henan Normal University, China.,Key Laboratory of Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, China
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91
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Huang Z, Wei Z, Tang M, Yu S, Jiao H. Biological treatments of mercury and nitrogen oxides in flue gas: biochemical foundations, technological potentials, and recent advances. ADVANCES IN APPLIED MICROBIOLOGY 2021; 116:133-168. [PMID: 34353503 DOI: 10.1016/bs.aambs.2021.04.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Nitrogen oxides (NOx) and mercury (Hg) are commonly found coexistent pollutants in combustion flue gas. Ever-increasing emission of atmospheric Hg and NOx has caused considerable environmental risks. Traditional flue gas demercuration and denitration techniques have many socioeconomic, technological and environmental drawbacks. Biotechnologies can be a promising and prospective alternative strategy. This article discusses theoretical foundation (biochemistry and genomic basis) and technical potentials (Hg0 bio-oxidation coupled to denitrification) of bioremoval of Hg and NOx in flue gas and summarized recent experimental and technological advances. Finally, several specific technical perspectives have been put forward to better guide future researches.
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Affiliation(s)
- Zhenshan Huang
- School of Environmental Science and Engineering, Sun Yat-sen University; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Guangzhou, 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, China.
| | - Meiru Tang
- School of Environmental Science and Engineering, Sun Yat-sen University; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Guangzhou, China
| | - Shan Yu
- School of Environmental Science and Engineering, Sun Yat-sen University; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Guangzhou, China
| | - Huaiyong Jiao
- School of Environmental Science and Engineering, Sun Yat-sen University; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Guangzhou, China
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92
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Sharma P. Efficiency of bacteria and bacterial assisted phytoremediation of heavy metals: An update. BIORESOURCE TECHNOLOGY 2021; 328:124835. [PMID: 33618184 DOI: 10.1016/j.biortech.2021.124835] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 02/05/2021] [Accepted: 02/07/2021] [Indexed: 05/12/2023]
Abstract
The aim of this review to address the plant-associated bacteria to enhance the phytoremediation efficiency of the heavy metals from polluted sites and it is also highlighted advances for the application in wastewater treatment. Plant-associated bacteria have potential to encourage the plant growth and resistance under stress conditions. Such bacteria could enhance plant growth by controlling growth hormone, nutrition security, producing siderophore, secondary metabolites, and improving the antioxidant enzymes system. This review also explores the concepts and applications of bacteria assisted phytoremediation, addressing aspects that affect phytoremediation and pathways for restoration. Significant review issues relating to production and application of bacteria for improvement of bioremediation were established and presented for possible future research. Bacteria assisted phytoremediation is cost-effective strategy and metal sequestration mechanism that hold high metal biosorption capacities. This also takes into consideration the current state of technology implementations and proposals for prospective clean-up studies.
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Affiliation(s)
- Pooja Sharma
- Department of Environmental Microbiology, School for Environmental Sciences, Babasaheb Bhimrao Ambedkar Central University, Lucknow 226 025, Uttar Pradesh, India
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93
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Yuan C, Li F, Yuan Z, Li G, Liang X. Response of bacterial communities to mining activity in the alpine area of the Tianshan Mountain region, China. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:15806-15818. [PMID: 33241503 DOI: 10.1007/s11356-020-11744-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 11/18/2020] [Indexed: 06/11/2023]
Abstract
Anthropogenic activities, such as mining, influence soil bacterial community composition and microbial distributions. In the current study, the patterns in microbial distribution and the environmental drivers shaping the soil bacterial community composition in the alpine mining area of the Tianshan Mountain region, China, were investigated, and the bacterial communities were analyzed using 16S rDNA pyrosequencing. The environmental factors and their relationships with the microbial community composition, structure, and diversity were also assessed. The soil organic carbon (SOC) concentration increased along the elevation gradient, with the highest concentration in the mining area, which increased microbial abundance and species richness. Some metals, like Ca, Cu, Pb, and Zn, accumulated significantly in the tailing area and were negatively correlated with the microbial community structure. Proteobacteria, Acidobacteria, Actinobacteria, and Verrucomicrobia were the dominant phyla; these dominant phyla were more abundant in the areas without mining than in the areas with mining at the same altitude. The relative abundance of Proteobacteria and Verrucomicrobia significantly increased along the elevation gradient, while that of Actinobacteria in the mining camp area was more than twice those in the other areas due to higher soil pH. Soil biomass was the highest in the valley. Collectively, these results elucidate the influence of anthropogenic mining activities on soil microbial communities in alpine mining soils and provide a basis for the future management of heavy metal-contaminated areas using the indigenous dominant bacterial phyla.
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Affiliation(s)
- Chengyu Yuan
- College of Water Resources and Architectural Engineering, Tarim University, Xinjiang, 843300, China
| | - Fayong Li
- College of Water Resources and Architectural Engineering, Tarim University, Xinjiang, 843300, China.
| | - Ziqiang Yuan
- Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Guoyu Li
- Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Xinqiang Liang
- College of Environmental and Resources Sciences, Zhejiang University, Hangzhou, 310058, China
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94
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Hu L, Liu B, Li S, Zhong H, He Z. Study on the oxidative stress and transcriptional level in Cr(VI) and Hg(II) reducing strain Acinetobacter indicus yy-1 isolated from chromium-contaminated soil. CHEMOSPHERE 2021; 269:128741. [PMID: 33127119 DOI: 10.1016/j.chemosphere.2020.128741] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 09/22/2020] [Accepted: 10/22/2020] [Indexed: 06/11/2023]
Abstract
The bioreduction of Cr(VI) and Hg(II) has become a hot topic in the field of heavy metals bioremediation. However, the mechanism of antioxidant stress in Cr(VI) and Hg(II) reducing bacteria is still not clear. In this work, a novel Cr(VI) and Hg(II) reducing strain Acinetobacter indicus yy-1, was isolated from chromium landfill at a chromate factory, which was used to investigate the mechanism of antioxidant stress during the Cr(VI) and Hg(II) reduction process. The results demonstrated that the removal of Cr(VI) and Hg(II) by A. indicus yy-1 from solution was through reduction rather than biosorption. The reduction rates of Cr(VI) and Hg(II) by resting cells reached 59.71% and 31.73% at 24 h with initial concentration of 10 mg L-1, respectively. X-ray photoelectron spectroscopy (XPS) analysis further showed that Cr(III) and Hg(0) were mainly the Cr(VI)- and Hg(II)-reduced productions, respectively. Results of physiological assays showed Hg(II) was more toxic to A. indicus yy-1 than Cr(VI), and the activities of antioxidant enzymes (SOD and CAT) were significantly increased in A. indicus yy-1 for relieving the oxidative stress. The transcriptional level of genes related to Cr(VI) and Hg(II) reductases and antioxidant enzymes were up-regulated, indicating that the reductases have participated in the reduction of Cr(VI) and Hg(II), and SOD and CAT served as the vital antioxidant enzymes for defending the oxidative stress. This work provides a deep insight into the mechanism of antioxidant stress in Cr(VI) and Hg(II) reducing bacteria, which helps seek the highly resistant heavy metal reducing bacteria.
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Affiliation(s)
- Liang Hu
- School of Minerals Processing and Bioengineering, Key Laboratory of Biohydrometallurgy of Ministry of Education, Central South University, Changsha, 410083, China
| | - Bang Liu
- School of Minerals Processing and Bioengineering, Key Laboratory of Biohydrometallurgy of Ministry of Education, Central South University, Changsha, 410083, China
| | - Shuzhen Li
- School of Minerals Processing and Bioengineering, Key Laboratory of Biohydrometallurgy of Ministry of Education, Central South University, Changsha, 410083, China
| | - Hui Zhong
- School of Life Science, Central South University, Changsha, 410012, China.
| | - Zhiguo He
- School of Minerals Processing and Bioengineering, Key Laboratory of Biohydrometallurgy of Ministry of Education, Central South University, Changsha, 410083, China.
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95
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Cui J, Xie Y, Sun T, Chen L, Zhang W. Deciphering and engineering photosynthetic cyanobacteria for heavy metal bioremediation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 761:144111. [PMID: 33352345 DOI: 10.1016/j.scitotenv.2020.144111] [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: 10/07/2020] [Revised: 11/22/2020] [Accepted: 11/22/2020] [Indexed: 06/12/2023]
Abstract
Environmental pollution caused by heavy metals has received worldwide attentions due to their ubiquity, poor degradability and easy bioaccumulation in host cells. As one potential solution, photosynthetic cyanobacteria have been considered as promising remediation chassis and widely applied in various bioremediation processes of heavy-metals. Meanwhile, deciphering resistant mechanisms and constructing tolerant chassis towards heavy metals could greatly contribute to the successful application of the cyanobacteria-based bioremediation in the future. In this review, first we summarized recent application of cyanobacteria in heavy metals bioremediation using either live or dead cells. Second, resistant mechanisms and strategies for enhancing cyanobacterial bioremediation of heavy metals were discussed. Finally, potential challenges and perspectives for improving bioremediation of heavy metals by cyanobacteria were presented.
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Affiliation(s)
- Jinyu Cui
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin 300072, PR China; Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering, Ministry of Education of China, Tianjin 300072, PR China; Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, PR China
| | - Yaru Xie
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin 300072, PR China; Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering, Ministry of Education of China, Tianjin 300072, PR China; Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, PR China
| | - Tao Sun
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin 300072, PR China; Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering, Ministry of Education of China, Tianjin 300072, PR China; Center for Biosafety Research and Strategy, Tianjin University, Tianjin 300072, PR China; Law School of Tianjin University, Tianjin 300072, PR China.
| | - Lei Chen
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin 300072, PR China; Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering, Ministry of Education of China, Tianjin 300072, PR China; Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, PR China.
| | - Weiwen Zhang
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin 300072, PR China; Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering, Ministry of Education of China, Tianjin 300072, PR China; Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, PR China; Center for Biosafety Research and Strategy, Tianjin University, Tianjin 300072, PR China; Law School of Tianjin University, Tianjin 300072, PR China
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96
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Manceau A, Nagy KL, Glatzel P, Bourdineaud JP. Acute Toxicity of Divalent Mercury to Bacteria Explained by the Formation of Dicysteinate and Tetracysteinate Complexes Bound to Proteins in Escherichia coli and Bacillus subtilis. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:3612-3623. [PMID: 33629845 DOI: 10.1021/acs.est.0c05202] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Bacteria are the most abundant organisms on Earth and also the major life form affected by mercury (Hg) poisoning in aquatic and terrestrial food webs. In this study, we applied high energy-resolution X-ray absorption near edge structure (HR-XANES) spectroscopy to bacteria with intracellular concentrations of Hg as low as 0.7 ng/mg (ppm) for identifying the intracellular molecular forms and trafficking pathways of Hg in bacteria at environmentally relevant concentrations. Gram-positive Bacillus subtilis and Gram-negative Escherichia coli were exposed to three Hg species: HgCl2, Hg-dicysteinate (Hg(Cys)2), and Hg-dithioglycolate (Hg(TGA)2). In all cases, Hg was transformed into new two- and four-coordinate cysteinate complexes, interpreted to be bound, respectively, to the consensus metal-binding CXXC motif and zinc finger domains of proteins, with glutathione acting as a transfer ligand. Replacement of zinc cofactors essential to gene regulatory proteins with Hg would inhibit vital functions such as DNA transcription and repair and is suggested to be a main cause of Hg genotoxicity.
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Affiliation(s)
- Alain Manceau
- Université Grenoble Alpes, CNRS, ISTerre, CS 40700, 38058 Grenoble, France
| | - Kathryn L Nagy
- Department of Earth and Environmental Sciences, University of Illinois at Chicago, MC-186, 845 West Taylor Street, Chicago, Illinois 60607, United States
| | - Pieter Glatzel
- European Synchrotron Radiation Facility (ESRF), 71 Rue des Martyrs, 38000 Grenoble, France
| | - Jean-Paul Bourdineaud
- Institut Européen de Chimie et Biologie, Université de Bordeaux, CNRS, UMR 5234, 2 rue Escarpit, 33607 Pessac, France
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97
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Pöntinen AK, Top J, Arredondo-Alonso S, Tonkin-Hill G, Freitas AR, Novais C, Gladstone RA, Pesonen M, Meneses R, Pesonen H, Lees JA, Jamrozy D, Bentley SD, Lanza VF, Torres C, Peixe L, Coque TM, Parkhill J, Schürch AC, Willems RJL, Corander J. Apparent nosocomial adaptation of Enterococcus faecalis predates the modern hospital era. Nat Commun 2021; 12:1523. [PMID: 33750782 PMCID: PMC7943827 DOI: 10.1038/s41467-021-21749-5] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 02/05/2021] [Indexed: 12/20/2022] Open
Abstract
Enterococcus faecalis is a commensal and nosocomial pathogen, which is also ubiquitous in animals and insects, representing a classical generalist microorganism. Here, we study E. faecalis isolates ranging from the pre-antibiotic era in 1936 up to 2018, covering a large set of host species including wild birds, mammals, healthy humans, and hospitalised patients. We sequence the bacterial genomes using short- and long-read techniques, and identify multiple extant hospital-associated lineages, with last common ancestors dating back as far as the 19th century. We find a population cohesively connected through homologous recombination, a metabolic flexibility despite a small genome size, and a stable large core genome. Our findings indicate that the apparent hospital adaptations found in hospital-associated E. faecalis lineages likely predate the "modern hospital" era, suggesting selection in another niche, and underlining the generalist nature of this nosocomial pathogen.
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Affiliation(s)
- Anna K Pöntinen
- Department of Biostatistics, Faculty of Medicine, University of Oslo, Oslo, Norway.
| | - Janetta Top
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Sergio Arredondo-Alonso
- Department of Biostatistics, Faculty of Medicine, University of Oslo, Oslo, Norway
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | | | - Ana R Freitas
- UCIBIO/REQUIMTE, Laboratory of Microbiology, Biological Sciences Department, Faculty of Pharmacy, University of Porto, Porto, Portugal
| | - Carla Novais
- UCIBIO/REQUIMTE, Laboratory of Microbiology, Biological Sciences Department, Faculty of Pharmacy, University of Porto, Porto, Portugal
| | - Rebecca A Gladstone
- Department of Biostatistics, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Maiju Pesonen
- Oslo Centre for Biostatistics and Epidemiology (OCBE), Oslo University Hospital Research Support Services, Oslo, Norway
| | - Rodrigo Meneses
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Henri Pesonen
- Department of Biostatistics, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - John A Lees
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, UK
| | - Dorota Jamrozy
- Parasites and Microbes, Wellcome Sanger Institute, Cambridge, UK
| | | | | | - Carmen Torres
- Department of Food and Agriculture, Area of Biochemistry and Molecular Biology, University of La Rioja, Logroño, Spain
| | - Luisa Peixe
- UCIBIO/REQUIMTE, Laboratory of Microbiology, Biological Sciences Department, Faculty of Pharmacy, University of Porto, Porto, Portugal
| | - Teresa M Coque
- Department of Microbiology, Ramón y Cajal Institute for Health Research Ramón y Cajal University Hospital, Madrid, Spain
- CIBER in Epidemiology and Public Health (CIBERESP), Madrid, Spain
| | - Julian Parkhill
- Wellcome Sanger Institute, Cambridge, UK
- Department of Veterinary Medicine, University of Cambridge, Cambridge, UK
| | - Anita C Schürch
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Rob J L Willems
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Jukka Corander
- Department of Biostatistics, Faculty of Medicine, University of Oslo, Oslo, Norway.
- Parasites and Microbes, Wellcome Sanger Institute, Cambridge, UK.
- Helsinki Institute of Information Technology, Department of Mathematics and Statistics, University of Helsinki, Helsinki, Finland.
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98
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Etique M, Bouchet S, Byrne JM, ThomasArrigo LK, Kaegi R, Kretzschmar R. Mercury Reduction by Nanoparticulate Vivianite. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:3399-3407. [PMID: 33554594 PMCID: PMC7931808 DOI: 10.1021/acs.est.0c05203] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 01/15/2021] [Accepted: 01/22/2021] [Indexed: 05/24/2023]
Abstract
Mercury (Hg) is a toxic trace element of global environmental concern which has been increasingly dispersed into the environment since the industrial revolution. In aquatic and terrestrial systems, Hg can be reduced to elemental Hg (Hg0) and escape to the atmosphere or converted to methylmercury (MeHg), a potent neurotoxin that accumulates in food webs. FeII-bearing minerals such as magnetite, green rusts, siderite, and mackinawite are recognized HgII reducers. Another potentially Hg-reducing mineral, which commonly occurs in Fe- and organic/P-rich sediments and soils, is the ferrous iron phosphate mineral vivianite (FeII3(PO4)2·8H2O), but its reaction with HgII has not been studied to date. Here, nanoparticulate vivianite (particle size ∼ 50 nm; FeII content > 98%) was chemically synthesized and characterized by a combination of chemical, spectroscopic, and microscopic analyses. Its ability to reduce HgII was investigated at circumneutral pH under anoxic conditions over a range of FeII/HgII ratios (0.1-1000). For FeII/HgII ratios ≥1, which are representative of natural environments, HgII was very quickly and efficiently reduced to Hg0. The ability of vivianite to reduce HgII was found to be similar to those of carbonate green rust and siderite, two of the most effective Hg-reducing minerals. Our results suggest that vivianite may be involved in abiotic HgII reduction in Fe and organic/P-rich soils and sediments, potentially contributing to Hg evasion while also limiting MeHg formation in these ecosystems.
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Affiliation(s)
- Marjorie Etique
- Soil Chemistry Group, Institute of Biogeochemistry and
Pollutant Dynamics, Department of Environmental Systems Science, ETH
Zürich, Universitätstrasse 16, CHN, 8092 Zürich,
Switzerland
| | - Sylvain Bouchet
- Soil Chemistry Group, Institute of Biogeochemistry and
Pollutant Dynamics, Department of Environmental Systems Science, ETH
Zürich, Universitätstrasse 16, CHN, 8092 Zürich,
Switzerland
| | - James M. Byrne
- School of Earth Sciences, University of
Bristol, Wills Memorial Building, Queens Road, BS8 1RJ Bristol,
U.K.
| | - Laurel K. ThomasArrigo
- Soil Chemistry Group, Institute of Biogeochemistry and
Pollutant Dynamics, Department of Environmental Systems Science, ETH
Zürich, Universitätstrasse 16, CHN, 8092 Zürich,
Switzerland
| | - Ralf Kaegi
- Eawag, Swiss Federal Institute of Aquatic
Science and Technology, Überlandstrasse 133, 8600 Dübendorf,
Switzerland
| | - Ruben Kretzschmar
- Soil Chemistry Group, Institute of Biogeochemistry and
Pollutant Dynamics, Department of Environmental Systems Science, ETH
Zürich, Universitätstrasse 16, CHN, 8092 Zürich,
Switzerland
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99
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Salam LB, Obayori OS, Ilori MO, Amund OO. Acenaphthene biodegradation and structural and functional metagenomics of the microbial community of an acenaphthene-enriched animal charcoal polluted soil. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2021. [DOI: 10.1016/j.bcab.2021.101951] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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100
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He P, Huang J, Yu Z, Xu X, Raga R, Lü F. Antibiotic resistance contamination in four Italian municipal solid waste landfills sites spanning 34 years. CHEMOSPHERE 2021; 266:129182. [PMID: 33333336 DOI: 10.1016/j.chemosphere.2020.129182] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 11/28/2020] [Accepted: 11/30/2020] [Indexed: 06/12/2023]
Abstract
Municipal solid waste landfill is now recognized as a significant reservoir of antibiotics and antibiotic resistance genes (ARGs). This study investigates the contamination of antibiotics resistance, in 10 leachate samples collected from four MSW landfills in north Italy spanning 34 years, including ARGs as well as mobile genetic element (MGEs). Antibiotics (0-434740 ng/L) and ARGs (5.56-6.85 × 105copies/μL leachate) were found in leachate. Abundances of the measured ARGs were found to be clustered into two groups with different changing tendencies with landfilling age in different landfills. Even though some antibiotics were banned or limited in Italy, they were found to still occur in landfills and drive the long-term contamination of ARGs indirectly, indicating the persistence of antibiotic resistance. What's more, the complexity of antibiotic resistance in leachate was found to synthetically relate to antibiotics, metals, microbes and MGEs presenting that Mn, SMX and EFC influence positively (p < 0.01) the contamination of tetW, tetQ, tetM, tetA, ermB, and cat, contributing importantly in new leachate. This study discusses the AR pollution of leachate in Italy where antibiotics are used the most in Europe, less reported in literatures. Our results suggest that a full-scale view for landfill antibiotics resistance should be considered with history of landfills, use of antibiotics and different phase in landfills, with both "relative static" and "dynamic tracking" perspective to focus on the principal antibiotic-resistance pollutants for leachate treatment, and raise the attention for landfill post-closure care and landfill mining.
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Affiliation(s)
- Pinjing He
- State Key Laboratory of Pollution Control and Resources Reuse, Tongji University, Shanghai, 200092, PR China; Institute of Waste Treatment & Reclamation, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, PR China
| | - Jinghua Huang
- State Key Laboratory of Pollution Control and Resources Reuse, Tongji University, Shanghai, 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, PR China
| | - Zhuofeng Yu
- State Key Laboratory of Pollution Control and Resources Reuse, Tongji University, Shanghai, 200092, PR China
| | - Xian Xu
- State Key Laboratory of Pollution Control and Resources Reuse, Tongji University, Shanghai, 200092, PR China
| | - Roberto Raga
- ICEA, Department of Civil, Environmental and Architectural Engineering, University of Padova, Via Marzolo, 9, 35131, Padova, Italy.
| | - Fan Lü
- State Key Laboratory of Pollution Control and Resources Reuse, Tongji University, Shanghai, 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, PR China.
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