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Halema AA, El-Beltagi HS, Al-Dossary O, Alsubaie B, Henawy AR, Rezk AA, Almutairi HH, Mohamed AA, Elarabi NI, Abdelhadi AA. Omics technology draws a comprehensive heavy metal resistance strategy in bacteria. World J Microbiol Biotechnol 2024; 40:193. [PMID: 38709343 DOI: 10.1007/s11274-024-04005-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Accepted: 04/24/2024] [Indexed: 05/07/2024]
Abstract
The rapid industrial revolution significantly increased heavy metal pollution, becoming a major global environmental concern. This pollution is considered as one of the most harmful and toxic threats to all environmental components (air, soil, water, animals, and plants until reaching to human). Therefore, scientists try to find a promising and eco-friendly technique to solve this problem i.e., bacterial bioremediation. Various heavy metal resistance mechanisms were reported. Omics technologies can significantly improve our understanding of heavy metal resistant bacteria and their communities. They are a potent tool for investigating the adaptation processes of microbes in severe conditions. These omics methods provide unique benefits for investigating metabolic alterations, microbial diversity, and mechanisms of resistance of individual strains or communities to harsh conditions. Starting with genome sequencing which provides us with complete and comprehensive insight into the resistance mechanism of heavy metal resistant bacteria. Moreover, genome sequencing facilitates the opportunities to identify specific metal resistance genes, operons, and regulatory elements in the genomes of individual bacteria, understand the genetic mechanisms and variations responsible for heavy metal resistance within and between bacterial species in addition to the transcriptome, proteome that obtain the real expressed genes. Moreover, at the community level, metagenome, meta transcriptome and meta proteome participate in understanding the microbial interactive network potentially novel metabolic pathways, enzymes and gene species can all be found using these methods. This review presents the state of the art and anticipated developments in the use of omics technologies in the investigation of microbes used for heavy metal bioremediation.
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Affiliation(s)
- Asmaa A Halema
- Genetics Department, Faculty of Agriculture, Cairo University, Giza, 12613, Egypt
| | - Hossam S El-Beltagi
- Agricultural Biotechnology Department, College of Agriculture and Food Sciences, King Faisal University, Al-Ahsa, 31982, Saudi Arabia.
- Biochemistry Department, Faculty of Agriculture, Cairo University, Giza, 12613, Egypt.
| | - Othman Al-Dossary
- Agricultural Biotechnology Department, College of Agriculture and Food Sciences, King Faisal University, Al-Ahsa, 31982, Saudi Arabia
| | - Bader Alsubaie
- Agricultural Biotechnology Department, College of Agriculture and Food Sciences, King Faisal University, Al-Ahsa, 31982, Saudi Arabia
| | - Ahmed R Henawy
- Microbiology Department, Faculty of Agriculture, Cairo University, Giza, 12613, Egypt
| | - Adel A Rezk
- Agricultural Biotechnology Department, College of Agriculture and Food Sciences, King Faisal University, Al-Ahsa, 31982, Saudi Arabia
- Plant Virology Department, Plant Pathology Research Institute, Agriculture Research Center, Giza, 12619, Egypt
| | - Hayfa Habes Almutairi
- Chemistry Department, College of Science, King Faisal University, Al-Ahsa, 31982, Saudi Arabia
| | - Amal A Mohamed
- Chemistry Dept, Al-Leith University College, Umm Al-Qura University, P.O. Box 6725- 21955, Makkah, Saudi Arabia
| | - Nagwa I Elarabi
- Genetics Department, Faculty of Agriculture, Cairo University, Giza, 12613, Egypt
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Kalita N, Baruah PP. Copper removal efficacy and stress tolerance potential of Leptolyngbya sp. GUEco1015. Heliyon 2024; 10:e29131. [PMID: 38644834 PMCID: PMC11033120 DOI: 10.1016/j.heliyon.2024.e29131] [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: 02/04/2024] [Revised: 03/18/2024] [Accepted: 04/01/2024] [Indexed: 04/23/2024] Open
Abstract
Cyanobacteria, a group of microalgae are the potent organism having the ability to survive in the copper rich environment and recently gained too much attention for their profuse proliferation in such water bodies. Amongst the members of cyanobacteria, the current study was conducted on Leptolyngbya sp. GUEco1015, collected from hydrocarbon rich water bodies of Assam, India. Morphological images of treated samples showed a remarkable damage in the cell surface as well as the organelles over the control. Biochemical results revealed a significant increase of enzymatic and non-enzymatic antioxidants during oxidative damage of Cu2+. But, ascorbate in 1.2 ppm (p < 0.01), 1.5 ppm (p < 0.001) and catalase content 1.5 ppm (p < 0.05) showed a significant reduction after a certain level. The cells were optimized to evaluate the maximum Cu2+ removal potential by the cells related to growth. Initial metal concentration 0.1 ppm, pH 7.5, temperature 25 °C and shaking rate 100 rpm are the optimized abiotic parameters which showed maximum 83% of Cu2+ removal. FTIR spectroscopy and EDX data has identified a number of notable functional groups that were involved in Cu2+ binding mechanism and revealed a distinctive peak of Cu with 0.41 wt % which makes the species as one of the competent copper adsorbents.
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Affiliation(s)
- Nilamjyoti Kalita
- Plant Ecology Laboratory, Dept. of Botany, Gauhati University, Gopinath Bordoloi Nagar, Jalukbari, Guwahati, Assam 781014, India
| | - Partha Pratim Baruah
- Plant Ecology Laboratory, Dept. of Botany, Gauhati University, Gopinath Bordoloi Nagar, Jalukbari, Guwahati, Assam 781014, India
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Li Y, Zhou C, Chen L, Deng R, Wong M, Shan S. Effects of biochar on the manganese enrichment and oxidation by a microalga Scenedesmus quadricauda in the aquatic environment. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2024; 271:115961. [PMID: 38218106 DOI: 10.1016/j.ecoenv.2024.115961] [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: 07/22/2023] [Revised: 10/25/2023] [Accepted: 01/06/2024] [Indexed: 01/15/2024]
Abstract
Microalgae play a significant impact in the biogeochemical cycle of Mn(II) in the aquatic ecosystem. Meanwhile, the inflow of biochar into the water bodies is bound to impact the aquatic organisms. However, the influence of biochar on the manganese transformation in algae-rich water has not drawn much attention. Thus, we studied the effects of rice straw biochar on manganese enrichment and oxidation by a common type of algae in freshwater (Scenedesmus quadricauda). The results showed that Mn(II) was absorbed intracellularly and adsorbed extracellularly by active algal cells. A significant portion of enriched Mn(II) was oxidized to amorphous precipitates MnO2, MnOOH, and Mn2O3. Moreover, the extracellular bound Mn(II) content in the coexistent system of algae and biochar increased compared with the pure Scenedesmus quadricauda system. Nevertheless, the intracellular Mn content was continually lowered as the biochar dose rose from an initial 0.2 to 2.0 g·L-1, suggesting that Mn assimilation of the cell was suppressed. It was calculated that the total enrichment ability of Scenedesmus quadricauda in the algae-biochar coexistent system was 0.31- 15.32 mg Mn/g biomass, more than that in the pure algae system. More importantly, with biochar in the algae system, the amount of generated MnOx increased, and more Mn(II) was oxidized into highly-charged Mn(IV). This was probably because the biochar could relieve the stress of massive Mn(II) on algae and support the MnOx precipitates. In brief, moderate biochar promoted the Mn(II) accumulation by algal cells and its oxidation activity. This study offers deeper insight into the bioconversion of Mn(II) by algae and the potential impact of biochar application to the aquatic system.
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Affiliation(s)
- Yongchao Li
- Key Laboratory of Recycling and Eco-Treatment of Waste Biomass of Zhejiang Province, School of Environmental and Natural Resources, Zhejiang University of Science and Technology, Hangzhou 310023, PR China; School of Civil Engineering, Hunan University of Science and Technology, Xiangtan 411201, PR China.
| | - Chuanfeng Zhou
- Key Laboratory of Recycling and Eco-Treatment of Waste Biomass of Zhejiang Province, School of Environmental and Natural Resources, Zhejiang University of Science and Technology, Hangzhou 310023, PR China
| | - Liping Chen
- School of Civil Engineering, Hunan University of Science and Technology, Xiangtan 411201, PR China
| | - Renjian Deng
- School of Civil Engineering, Hunan University of Science and Technology, Xiangtan 411201, PR China
| | - Minghung Wong
- Key Laboratory of Recycling and Eco-Treatment of Waste Biomass of Zhejiang Province, School of Environmental and Natural Resources, Zhejiang University of Science and Technology, Hangzhou 310023, PR China; Consortium on Health, Environment, Education, and Research (CHEER), Department of Science and Environmental Studies, The Education University of Hong Kong, 10 Lo Ping Road, Tai Po, Hong Kong SAR, PR China
| | - Shengdao Shan
- Key Laboratory of Recycling and Eco-Treatment of Waste Biomass of Zhejiang Province, School of Environmental and Natural Resources, Zhejiang University of Science and Technology, Hangzhou 310023, PR China
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Schommer VA, Nazari MT, Melara F, Braun JCA, Rempel A, Dos Santos LF, Ferrari V, Colla LM, Dettmer A, Piccin JS. Techniques and mechanisms of bacteria immobilization on biochar for further environmental and agricultural applications. Microbiol Res 2024; 278:127534. [PMID: 37944206 DOI: 10.1016/j.micres.2023.127534] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 10/02/2023] [Accepted: 10/19/2023] [Indexed: 11/12/2023]
Abstract
Bacteria immobilization on biochar is a promising approach to achieve high concentration and stability of microbial cells for several applications. The present review addressed the techniques utilized for bacteria immobilization on biochar, discussing the mechanisms involved in this process, as well as the further utilization in bioremediation and agriculture. This article presents three immobilization techniques, which vary according to their procedures and conditions, including cell growth, adsorption, and adaptation. The mechanisms for cell immobilization are primarily adsorption and biofilm formation on biochar. The favorable characteristics of biochar immobilization depend on the pyrolysis methods, raw materials, and properties of biochar, such as surface area, pore size, pH, zeta potential, hydrophobicity, functional groups, and nutrients. Scanning electron microscope (SEM) and colony forming unit (CFU) are the analyses commonly carried out to verify the efficiency of bacteria immobilization. The benefits of applying biochar-immobilized bacteria include soil decontamination and quality improvement, which can improve plant growth and crop yield. Therefore, this emerging technology represents a promising solution for environmental and agricultural purposes. However, it is important to evaluate the potential adverse impacts on native microbiota by introducing exogenous microorganisms.
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Affiliation(s)
- Vera Analise Schommer
- Graduate Program in Civil and Environmental Engineering (PPGEng), University of Passo Fundo (UPF), Passo Fundo, RS, Brazil.
| | - Mateus Torres Nazari
- Graduate Program in Civil and Environmental Engineering (PPGEng), University of Passo Fundo (UPF), Passo Fundo, RS, Brazil.
| | - Flávia Melara
- Graduate Program in Civil and Environmental Engineering (PPGEng), University of Passo Fundo (UPF), Passo Fundo, RS, Brazil
| | - Julia Catiane Arenhart Braun
- Graduate Program in Civil and Environmental Engineering (PPGEng), University of Passo Fundo (UPF), Passo Fundo, RS, Brazil
| | - Alan Rempel
- Graduate Program in Civil and Environmental Engineering (PPGEng), University of Passo Fundo (UPF), Passo Fundo, RS, Brazil
| | - Lara Franco Dos Santos
- Graduate Program in Mining, Metallurgical and Materials Engineering (PPGE3M), Federal University of Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil
| | - Valdecir Ferrari
- Graduate Program in Bioexperimentation, University of Passo Fundo (UPF), Passo Fundo, RS, Brazil
| | - Luciane Maria Colla
- Graduate Program in Civil and Environmental Engineering (PPGEng), University of Passo Fundo (UPF), Passo Fundo, RS, Brazil.
| | - Aline Dettmer
- Graduate Program in Food Science and Technology (PPGCTA), University of Passo Fundo (UPF), Passo Fundo, RS, Brazil
| | - Jeferson Steffanello Piccin
- Graduate Program in Civil and Environmental Engineering (PPGEng), University of Passo Fundo (UPF), Passo Fundo, RS, Brazil
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5
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Hu Z, Zhou Z, Zhou Y, Zheng L, Guo J, Liu Y, Sun Z, Yang Z, Yu X. Synergy of surface adsorption and intracellular accumulation for removal of uranium with Stenotrophomonas sp: Performance and mechanisms. ENVIRONMENTAL RESEARCH 2023; 220:115093. [PMID: 36574801 DOI: 10.1016/j.envres.2022.115093] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 12/10/2022] [Accepted: 12/15/2022] [Indexed: 06/17/2023]
Abstract
Uranium is well-known to have serious adverse effects on the ecological environment and human health. Bioremediation stands out among many remediation methods owing to its being economically feasible and environmentally friendly. This study reported a great promising strategy for eliminating uranium by Stenotrophomonas sp. CICC 23833 in the aquatic environment. The bacterium demonstrated excellent uranium adsorption capacity (qmax = 392.9 mg/g) because of the synergistic effect of surface adsorption and intracellular accumulation. Further analysis revealed that hydroxyl, carboxyl, phosphate groups and proteins of microorganisms were essential in uranium adsorption. Intracellular accumulation was closely related to cellular activity, and the efficiency of uranium processing by the permeabilized bacterial cells was significantly improved. In response to uranium stress, the bacterium was found to release multiple ions in conjunction with uranium adsorption, which facilitates the maintenance of bacterial life activities and the conversion of uranyl to precipitates. These above results indicated that Stenotrophomonas sp. Had great potential application value for the remediation of uranium.
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Affiliation(s)
- Zhongqiang Hu
- State Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, Jiangxi, China; School of Water Resources and Environmental Engineering, East China University of Technology, Nanchang 330013, Jiangxi, China
| | - Zhongkui Zhou
- State Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, Jiangxi, China; School of Water Resources and Environmental Engineering, East China University of Technology, Nanchang 330013, Jiangxi, China.
| | - Yaoyu Zhou
- State Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, Jiangxi, China; School of Water Resources and Environmental Engineering, East China University of Technology, Nanchang 330013, Jiangxi, China; College of Resources and Environment, Hunan Agricultural University, Changsha 410128, China.
| | - Lili Zheng
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Jianping Guo
- State Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, Jiangxi, China; School of Water Resources and Environmental Engineering, East China University of Technology, Nanchang 330013, Jiangxi, China
| | - Yong Liu
- State Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, Jiangxi, China; School of Water Resources and Environmental Engineering, East China University of Technology, Nanchang 330013, Jiangxi, China
| | - Zhanxue Sun
- State Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, Jiangxi, China; School of Water Resources and Environmental Engineering, East China University of Technology, Nanchang 330013, Jiangxi, China
| | - Zhihui Yang
- School of Metallurgy and Environment, Central South University, Changsha 410083, Hunan, China
| | - Xiaoxia Yu
- State Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, Jiangxi, China; School of Water Resources and Environmental Engineering, East China University of Technology, Nanchang 330013, Jiangxi, China
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Elarabi NI, Halema AA, Abdelhadi AA, Henawy AR, Samir O, Abdelhaleem HAR. Draft genome of Raoultella planticola, a high lead resistance bacterium from industrial wastewater. AMB Express 2023; 13:14. [PMID: 36715862 PMCID: PMC9885416 DOI: 10.1186/s13568-023-01519-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Accepted: 01/20/2023] [Indexed: 01/31/2023] Open
Abstract
Isolation of heavy metals-resistant bacteria from their original habitat is a crucial step in bioremediation. Six lead (Pb) resistant bacterial strains were isolated and identified utilizing 16S rRNA to be Enterobacter ludwigii FACU 4, Shigella flexneri FACU, Microbacterium paraoxydans FACU, Klebsiella pneumoniae subsp. pneumonia FACU, Raoultella planticola FACU 3 and Staphylococcus xylosus FACU. It was determined that all these strains had their Minimum inhibitory concentration (MIC) to be 2500 ppm except R. planticola FACU 3 has a higher maximum tolerance concentration (MTC) up to 2700 ppm. We evaluated the survival of all six strains on lead stress, the efficiency of biosorption and lead uptake. It was found that R. planticola FACU 3 is the highest MTC and S. xylosus FACU was the lowest MTC in this evaluation. Therefore, transmission electron microscopy (TEM) confirmed the difference between the morphological responses of these two strains to lead stress. These findings led to explore more about the genome of R. planticola FACU 3 using illumine Miseq technology. Draft genome sequence analysis revealed the genome size of 5,648,460 bp and G + C content 55.8% and identified 5526 CDS, 75 tRNA and 4 rRNA. Sequencing technology facilitated the identification of about 47 genes related to resistance to many heavy metals including lead, arsenic, zinc, mercury, nickel, silver and chromium of R. planticola FACU 3 strain. Moreover, genome sequencing identified plant growth-promoting genes (PGPGs) including indole acetic acid (IAA) production, phosphate solubilization, phenazine production, trehalose metabolism and 4-hydroxybenzoate production genes and a lot of antibiotic-resistant genes.
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Affiliation(s)
- Nagwa I. Elarabi
- grid.7776.10000 0004 0639 9286Genetics Department; Faculty of Agriculture, Cairo University, Giza, 12613 Egypt
| | - Asmaa A. Halema
- grid.7776.10000 0004 0639 9286Genetics Department; Faculty of Agriculture, Cairo University, Giza, 12613 Egypt ,grid.423564.20000 0001 2165 2866National Biotechnology Network of Expertise (NBNE), Academy of Scientific Research and Technology (ASRT), Cairo, Egypt
| | - Abdelhadi A. Abdelhadi
- grid.7776.10000 0004 0639 9286Genetics Department; Faculty of Agriculture, Cairo University, Giza, 12613 Egypt ,grid.423564.20000 0001 2165 2866National Biotechnology Network of Expertise (NBNE), Academy of Scientific Research and Technology (ASRT), Cairo, Egypt
| | - Ahmed R. Henawy
- grid.7776.10000 0004 0639 9286Department of Microbiology; Faculty of Agriculture, Cairo University, Giza, 12613 Egypt
| | - Omar Samir
- grid.428154.e0000 0004 0474 308XGenomic Research Program, Children’s Cancer Hospital, Cairo, Egypt
| | - Heba A. R. Abdelhaleem
- grid.440875.a0000 0004 1765 2064Biotechnology College, Misr University for Science and Technology (MUST), 6(th) October City, Egypt
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Balu S, Bhunia S, Gachhui R, Mukherjee J. Polycyclic aromatic hydrocarbon sequestration by intertidal phototrophic biofilms cultivated in hydrophobic and hydrophilic biofilm-promoting culture vessels. JOURNAL OF HAZARDOUS MATERIALS 2022; 437:129318. [PMID: 35749894 DOI: 10.1016/j.jhazmat.2022.129318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Revised: 05/24/2022] [Accepted: 06/05/2022] [Indexed: 06/15/2023]
Abstract
Phototrophic biofilms collected from intertidal sediments of the world's largest tidal mangrove forest were cultured in two sets of a biofilm-promoting culture vessel having hydrophilic glass surface and hydrophobic polymethyl methacrylate surface wherein 16 priority polycyclic aromatic hydrocarbons (PAHs) were spiked. Biofilms from three locations of the forest were most active in sequestering 98-100% of the spiked pollutants. PAH challenge did not alter the biofilm phototrophic community composition; rather biofilm biomass production and synthesis of photosynthetic pigments and extracellular polymeric substances (EPS) were enhanced. Photosynthetic pigment and EPS synthesis were sensitive to vessel-surface property. The lowest mean residual amounts of PAHs in the liquid medium as well as inside the biofilm were recorded in the very biofilm cultivated in the hydrophobic flask where highest values of biofilm biomass, total chlorophyll, released polysaccharidic (RPS) carbohydrates, RPS uronic acids, capsular polysaccharidic (CPS) carbohydrates, CPS proteins, CPS uronic acids and EPS hydrophobicity were obtained. Ratios of released RPS proteins: polysaccharides increased during PAH sequestration whereas the ratios of CPS proteins: polysaccharides remained constant. Efficacious PAH removal by the overlying phototrophic biofilm will reduce the entry of these contaminants in the sediments underneath and this strategy could be a model for "monitored natural recovery".
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Affiliation(s)
- Saranya Balu
- School of Environmental Studies, Jadavpur University, Kolkata 700032, India.
| | - Shantanu Bhunia
- School of Environmental Studies, Jadavpur University, Kolkata 700032, India.
| | - Ratan Gachhui
- Department of Life Science and Biotechnology, Jadavpur University, Kolkata 700032, India.
| | - Joydeep Mukherjee
- School of Environmental Studies, Jadavpur University, Kolkata 700032, India.
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Rathnayake IVN, Munagamage T, Pathirathne A, Megharaj M. Whole cell microalgal-cyanobacterial array biosensor for monitoring Cd, Cr and Zn in aquatic systems. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2021; 84:1579-1593. [PMID: 34662298 DOI: 10.2166/wst.2021.339] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Bioavailable content of metals in aquatic systems has become critical in assessing the toxic effect of metals accumulating in the environment. Considering the need for rapid measurements, an optical microalgal-cyanobacterial array biosensor was developed using two strains of microalgae, Mesotaenium sp. and a strain of cyanobacteria Synechococcus sp. to detect Cd2+, Cr6+ and Zn2+ in aquatic systems. Microalgal and cyanobacterial cells were immobilized in a 96-well microplate using sol-gel method using silica. Optimum operational conditions for the biosensor array such as exposure time, storage stability, pH, and multiple metal effect were tested. A 10 min exposure time yielded optimum fluorescence values. Metal toxicity increased with decreasing pH, resulting in low relative fluorescence (%) and decreased with increasing pH, resulting in higher relative fluorescence (%). The optimum storage time for biosensor strains were 4 weeks for microalgal cultures and 8 weeks for cyanobacterial culture, at 4 °C storage temperature. The metal mixtures showed less effect on the inhibition of relative fluorescence (%) of microalgal/cyanobacterial cultures, displaying an antagonistic behavior among the metals tested. As a single unit, this photosynthetic array biosensor will be a valuable tool in detecting multi-metals in aquatic systems.
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Affiliation(s)
- I V N Rathnayake
- Department of Microbiology, Faculty of Science, University of Kelaniya, Kelaniya, GQ 11600, Sri Lanka E-mail:
| | - Thilini Munagamage
- Department of Microbiology, Faculty of Science, University of Kelaniya, Kelaniya, GQ 11600, Sri Lanka E-mail:
| | - A Pathirathne
- Department of Zoology and Environmental Management, Faculty of Science, University of Kelaniya, Kelaniya, GQ 11600, Sri Lanka
| | - Mallavarapu Megharaj
- Global Centre for Environmental Remediation, School of Engineering, Science and Environment, The University of Newcastle, Callaghan, NSW 2308, Australia
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Li N, Qin L, Jin M, Zhang L, Geng W, Xiao X. Extracellular adsorption, intracellular accumulation and tolerance mechanisms of Cyclotella sp. to Cr(VI) stress. CHEMOSPHERE 2021; 270:128662. [PMID: 33127109 DOI: 10.1016/j.chemosphere.2020.128662] [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: 08/21/2020] [Revised: 10/13/2020] [Accepted: 10/15/2020] [Indexed: 06/11/2023]
Abstract
Heavy metals have caused widespread concern due to their adverse effects on aquatic organisms. However, there are few studies on their tolerance mechanism. In this study, the tolerance mechanisms of Cyclotella sp. to Cr(VI) were explored. The increase of antioxidant enzymes activity acting as a defense mechanism could help Cyclotella sp. to reduce the oxidative damage caused by the heavy metal Cr(VI). Cr(VI) was also combined with the functional groups on the cell surface to detoxify and was transported into the cell by binding to the carrier protein. In addition, it is worth noting that the molecular docking simulation showed that Cr(VI) combined with macromolecular compounds in cells through hydrogen and ionic bonds, which can reduce the toxicity of chromium. The determination of chromium content in cells showed that chromium was accumulated in cells. Furthermore, the low concentration of Cr(VI) had a growth stimulation on Cyclotella sp., while the growth of Cyclotella sp. microalgae was obvious inhibited when Cr(VI) concentration was over 0.5 mg/L. The content of Chlorophyll a (Chl-a) and soluble protein both had a dramatic change under the stress of Cr(VI). Cell ultrastructure analysis showed that plasmolysis phenomenon and dissolution of organelle structures when Cyclotella sp. was exposed to Cr(VI). The series of changes in Cyclotella sp. allow it to be an indicator of Cr(VI) pollution in water. Meanwhile, these findings were helpful to further understand the tolerance mechanism of Cr(VI) on microalgae and provide new insights to assess Cr(VI) toxicity to the microalgae.
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Affiliation(s)
- Na Li
- College of Safety and Environment Engineering, Shandong University of Science and Technology, Qingdao, 266510, China
| | - Liguo Qin
- College of Safety and Environment Engineering, Shandong University of Science and Technology, Qingdao, 266510, China
| | - Meng Jin
- College of Safety and Environment Engineering, Shandong University of Science and Technology, Qingdao, 266510, China
| | - Linlin Zhang
- College of Safety and Environment Engineering, Shandong University of Science and Technology, Qingdao, 266510, China
| | - Weiwei Geng
- College of Safety and Environment Engineering, Shandong University of Science and Technology, Qingdao, 266510, China
| | - Xinfeng Xiao
- College of Safety and Environment Engineering, Shandong University of Science and Technology, Qingdao, 266510, China.
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Liu ZX, Huang SL, Hou J, Guo XP, Wang FS, Sheng JZ. Cell-based high-throughput screening of polysaccharide biosynthesis hosts. Microb Cell Fact 2021; 20:62. [PMID: 33663495 PMCID: PMC7934428 DOI: 10.1186/s12934-021-01555-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 02/26/2021] [Indexed: 02/05/2023] Open
Abstract
Valuable polysaccharides are usually produced using wild-type or metabolically-engineered host microbial strains through fermentation. These hosts act as cell factories that convert carbohydrates, such as monosaccharides or starch, into bioactive polysaccharides. It is desirable to develop effective in vivo high-throughput approaches to screen cells that display high-level synthesis of the desired polysaccharides. Uses of single or dual fluorophore labeling, fluorescence quenching, or biosensors are effective strategies for cell sorting of a library that can be applied during the domestication of industrial engineered strains and metabolic pathway optimization of polysaccharide synthesis in engineered cells. Meanwhile, high-throughput screening strategies using each individual whole cell as a sorting section are playing growing roles in the discovery and directed evolution of enzymes involved in polysaccharide biosynthesis, such as glycosyltransferases. These enzymes and their mutants are in high demand as tool catalysts for synthesis of saccharides in vitro and in vivo. This review provides an introduction to the methodologies of using cell-based high-throughput screening for desired polysaccharide-biosynthesizing cells, followed by a brief discussion of potential applications of these approaches in glycoengineering.
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Affiliation(s)
- Zi-Xu Liu
- Key Laboratory of Chemical Biology of Natural Products (Ministry of Education), Institute of Biochemical and Biotechnological Drug, School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, 250012, China
| | - Si-Ling Huang
- Bloomage BioTechnology Corp., Ltd., Jinan, 250010, China
| | - Jin Hou
- The State Key Laboratory of Microbial Technology, Shandong University, Jinan, 250100, China
| | - Xue-Ping Guo
- Bloomage BioTechnology Corp., Ltd., Jinan, 250010, China
| | - Feng-Shan Wang
- Key Laboratory of Chemical Biology of Natural Products (Ministry of Education), Institute of Biochemical and Biotechnological Drug, School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, 250012, China. .,National Glycoengineering Research Center, Shandong University, Jinan, 250012, China.
| | - Ju-Zheng Sheng
- Key Laboratory of Chemical Biology of Natural Products (Ministry of Education), Institute of Biochemical and Biotechnological Drug, School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, 250012, China. .,National Glycoengineering Research Center, Shandong University, Jinan, 250012, China.
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11
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Lin Z, Li J, Luan Y, Dai W. Application of algae for heavy metal adsorption: A 20-year meta-analysis. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 190:110089. [PMID: 31896472 DOI: 10.1016/j.ecoenv.2019.110089] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 11/22/2019] [Accepted: 12/11/2019] [Indexed: 06/10/2023]
Abstract
The use of algae to adsorb heavy metals is an efficient and environmentally friendly treatment for contaminated water and has attracted widespread research attention. In this study, a meta-analysis of the heavy metal adsorption capacity of algae from five different phyla and the factors influencing these capacities was conducted. Phaeophyta was found to have a high heavy metal adsorption capacity, whereas Bacillariophyta had a relatively low adsorption capacity; Chlorophyta, Rhodophyta, and Cyanophyta had moderate adsorption capacities. Non-living algae were more effective in practical applications than living algae were. Algal biomass had a relatively high adsorption efficiency of 1-10 g/L, which did not increase significantly when algal concentration increased. The algal adsorption efficiency for initial heavy metal concentrations of 10-100 mg/L was higher than for concentrations of greater than 100 mg/L. The results further show that algal adsorption of heavy metals reached a maximum capacity of 80-90% within 20 min. Heavy metal adsorption by algae was not temperature-dependent, and it was more effective in moderately to weakly acidic environments (pH = 4-7.5). Considering these aspects for practical applications, algae from some phyla can effectively be used for heavy metal biosorption in contaminated water.
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Affiliation(s)
- Zeyu Lin
- College of Forestry, Beijing Forestry University, Beijing, 100083, China
| | - Jing Li
- College of Forestry, Beijing Forestry University, Beijing, 100083, China
| | - Yaning Luan
- College of Forestry, Beijing Forestry University, Beijing, 100083, China
| | - Wei Dai
- College of Forestry, Beijing Forestry University, Beijing, 100083, China.
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Thongpitak J, Pekkoh J, Pumas C. Remediation of Manganese-Contaminated Coal-Mine Water Using Bio-Sorption and Bio-Oxidation by the Microalga Pediastrum duplex (AARLG060): A Laboratory-Scale Feasibility Study. Front Microbiol 2019; 10:2605. [PMID: 31781081 PMCID: PMC6861300 DOI: 10.3389/fmicb.2019.02605] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Accepted: 10/28/2019] [Indexed: 02/04/2023] Open
Abstract
Acidification occurs as a result of acid mine drainage after the oxidative weathering of metal sulfides. The acidic condition corrodes other toxic elements from the soil and becomes distributed around the operating site. Although coal mines go through a process of rehabilitation, water samples in the rehabilitated reservoir still reveal high concentrations of certain metals, for example, manganese (Mn). Both living and non-living biomass substances were used in Mn remediation. However, using non-living biomass as a sorbent may be inappropriate for the purposes of upscaling in high-volume water bodies. Thus, living microalga, Pediastrum duplex AARLG060, has become of significant interest for this type of application. The Mn remediation of microalga was performed by biosorption and bio-oxidation. The aim of this study was to evaluate the potential of microalgal Mn remediation of the water obtained from a rehabilitated coal-mine reservoir. The equilibrium and isotherm values of the remediation process were also studied. The microalga was used to remediate Mn in water under three different water conditions, including filtrated water obtained from the rehabilitated site, non-filtrated water that was sterilized with an autoclave, and non-treated water. Remediation was performed by culturing microalga with modified medium consisting of N, P, C, and Mg nutrients. The remediated Mn concentration present in the cultures was detected by atomic absorption spectroscopy. The precipitated Mn was collected as a result of bio-oxidation, and EDTA was used to wash Mn from the biomass. This was designated as an adsorption result. Characterization of biosorption was evaluated by employing the Langmuir and Freundlich models. The results demonstrated that all treatments of living microalga could support Mn bio-oxidation. The Mn remediation was successfully performed at over 97% in every treatment. The adsorption characteristics revealed a close similarity to the Langmuir isotherm of monolayer adsorption. The scanning electron microscope-energy dispersive spectroscopy (SEM-EDS) indicated precipitation of Mn oxide on the cell surface, while transmission electron microscopy (TEM) revealed that the nanoparticles of Mn were scattered mainly in the chloroplast and throughout the vacuoles of the cells.
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Affiliation(s)
- Jakkapong Thongpitak
- Ph.D. Degree Program in Environmental Science, Environmental Science Research Center, Faculty of Science, Chiang Mai University, Chiang Mai, Thailand
| | - Jeeraporn Pekkoh
- Center of Excellence in Bioresources for Agriculture, Industry and Medicine, Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai, Thailand
| | - Chayakorn Pumas
- Center of Excellence in Bioresources for Agriculture, Industry and Medicine, Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai, Thailand
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13
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Moura KAF, Lizieri C, Wittig Franco M, Vaz MGMV, Araújo WL, Convey P, Barbosa FAR. Physiological and thylakoid ultrastructural changes in cyanobacteria in response to toxic manganese concentrations. ECOTOXICOLOGY (LONDON, ENGLAND) 2019; 28:1009-1021. [PMID: 31471822 DOI: 10.1007/s10646-019-02098-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 08/12/2019] [Indexed: 06/10/2023]
Abstract
In this study, two cyanobacterial strains (morphologically identified as Microcystis novacekii BA005 and Nostoc paludosum BA033) were exposed to different Mn concentrations: 7.0, 10.5, 15.7, 23.6 and 35.4 mg L-1 for BA005; and 15.0, 22.5, 33.7, 50.6, and 76.0 mg L-1 for BA033. Manganese toxicity was assessed by growth rate inhibition (EC50), chlorophyll a content, quantification of Mn accumulation in biomass and monitoring morphological and ultrastructural effects. The Mn EC50 values were 16 mg L-1 for BA005 and 39 mg L-1 for BA033, respectively. Reduction of chlorophyll a contents and ultrastructural changes were observed in cells exposed to Mn concentrations greater than 23.6 and 33.7 mg L-1 for BA005 and BA033. Damage to intrathylakoid spaces, increased amounts of polyphosphate granules and an increased number of carboxysomes were observed in both strains. In the context of the potential application of these strains in bioremediation approaches, BA005 was able to remove Mn almost completely from aqueous medium after 96 h exposure to an initial concentration of 10.5 mg L-1, and BA033 was capable of removing 38% when exposed to initial Mn concentration of 22.5 mg L-1. Our data shed light on how these cyanobacterial strains respond to Mn stress, as well as supporting their utility as organisms for monitoring Mn toxicity in industrial wastes and potential bioremediation application.
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Affiliation(s)
- Karen Ann Ferreira Moura
- Laboratório de Limnologia, Ecotoxicologia e Ecologia Aquática, Instituto de Ciências Biológicas, B. I3, 163, Universidade Federal de Minas Gerais, Avenida Antonio Carlos, 6627, Belo Horizonte, Minas Gerais, 31270-901, Brazil
| | - Claudineia Lizieri
- Laboratório de Limnologia, Ecotoxicologia e Ecologia Aquática, Instituto de Ciências Biológicas, B. I3, 163, Universidade Federal de Minas Gerais, Avenida Antonio Carlos, 6627, Belo Horizonte, Minas Gerais, 31270-901, Brazil
| | - Maione Wittig Franco
- Laboratório de Limnologia, Ecotoxicologia e Ecologia Aquática, Instituto de Ciências Biológicas, B. I3, 163, Universidade Federal de Minas Gerais, Avenida Antonio Carlos, 6627, Belo Horizonte, Minas Gerais, 31270-901, Brazil.
| | - Marcelo Gomes Marçal Vieira Vaz
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-900, Brazil
- Max Planck Partner Group at the Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-900, Brazil
| | - Wagner L Araújo
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-900, Brazil
- Max Planck Partner Group at the Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-900, Brazil
| | - Peter Convey
- British Antarctic Survey, NERC, High Cross, Madingley Road, Cambridge, CB3 0ET, UK
| | - Francisco Antônio Rodrigues Barbosa
- Laboratório de Limnologia, Ecotoxicologia e Ecologia Aquática, Instituto de Ciências Biológicas, B. I3, 163, Universidade Federal de Minas Gerais, Avenida Antonio Carlos, 6627, Belo Horizonte, Minas Gerais, 31270-901, Brazil
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Seifan M, Berenjian A. Application of microbially induced calcium carbonate precipitation in designing bio self-healing concrete. World J Microbiol Biotechnol 2018; 34:168. [PMID: 30387067 DOI: 10.1007/s11274-018-2552-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 10/29/2018] [Indexed: 12/25/2022]
Abstract
Concrete is one of the most broadly used construction materials in the world due to its number of performance characteristics. Despite the long life of concrete structure under ideal conditions, it tends to crack and this phenomenon results in a considerable reduction in service life and performance. Evidence of microbial involvement in the precipitation of minerals has led to a massive investigation on adapting this technology for addressing the concrete cracking issue. Calcium carbonate is one of most compatible materials with the concrete constituents and it can be induced via biological process. In this review paper, the effects of different factors, such as nucleation site, pH, nutrient and temperature, on the biosynthesis of calcium carbonate are elucidated. Moreover, the influences of effective factors on calcium carbonate polymorphism are extensively elaborated. Finally, the limitations for the future application of this innovative technology in construction industry are highlighted.
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Affiliation(s)
- Mostafa Seifan
- School of Engineering, Faculty of Science and Engineering, The University of Waikato, Hamilton, New Zealand
| | - Aydin Berenjian
- School of Engineering, Faculty of Science and Engineering, The University of Waikato, Hamilton, New Zealand.
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15
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Xu C, Sun T, Li S, Chen L, Zhang W. Adaptive laboratory evolution of cadmium tolerance in Synechocystis sp. PCC 6803. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:205. [PMID: 30061927 PMCID: PMC6058365 DOI: 10.1186/s13068-018-1205-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 07/16/2018] [Indexed: 05/08/2023]
Abstract
BACKGROUND Cadmium has been a significant threat to environment and human health due to its high toxicity and wide application in fossil-fuel burning and battery industry. Cyanobacteria are one of the most dominant prokaryotes, and the previous studies suggested that they could be valuable in removing Cd2+ from waste water. However, currently, the tolerance to cadmium is very low in cyanobacteria. To further engineer cyanobacteria for the environmental application, it is thus necessary to determine the mechanism that they respond to high concentration of cadmium. RESULTS In this study, a robust strain of Synechocystis PCC 6803 (named ALE-9.0) tolerant to CdSO4 with a concentration up to 9.0 µM was successfully isolated via adaptive laboratory evolution over 802-day continuous passages under cadmium stress. Whole-genome re-sequencing was then performed and nine mutations were identified for the evolved strain compared to the wild-type strain. Among these mutations, a large fragment deletion in slr0454 encoding a cation or drug efflux system protein was found to contribute directly to the resistance to Cd2+ stress. In addition, five other mutations were also demonstrated related to the improved Cd2+ tolerance in ALE-9.0. Moreover, the evolved ALE-9.0 strain was found to obtain cross tolerance to some other heavy metals like zinc and cobalt as well as higher resistance to high light. CONCLUSIONS The work here identified six genes and their mutations related to Cd2+ tolerance in Synechocystis PCC 6803, and demonstrated the feasibility of adaptive laboratory evolution in tolerance modifications. This work also provided valuable information regarding the cadmium tolerance mechanism in Synechocystis PCC 6803, and useful insights for cyanobacterial robustness and tolerance engineering.
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Affiliation(s)
- Chunxiao Xu
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin, 300072 People’s Republic of China
- Key Laboratory of Systems Bioengineering, Ministry of Education of China, Tianjin, 300072 People’s Republic of China
- Collaborative Innovation Center of Chemical Science and Engineering, Tianjin, People’s Republic of China
| | - Tao Sun
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin, 300072 People’s Republic of China
- Key Laboratory of Systems Bioengineering, Ministry of Education of China, Tianjin, 300072 People’s Republic of China
- Collaborative Innovation Center of Chemical Science and Engineering, Tianjin, People’s Republic of China
| | - Shubin Li
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin, 300072 People’s Republic of China
- Key Laboratory of Systems Bioengineering, Ministry of Education of China, Tianjin, 300072 People’s Republic of China
- Collaborative Innovation Center of Chemical Science and Engineering, Tianjin, People’s Republic of China
| | - Lei Chen
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin, 300072 People’s Republic of China
- Key Laboratory of Systems Bioengineering, Ministry of Education of China, Tianjin, 300072 People’s Republic of China
- Collaborative Innovation Center of Chemical Science and Engineering, Tianjin, People’s Republic of China
| | - Weiwen Zhang
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin, 300072 People’s Republic of China
- Key Laboratory of Systems Bioengineering, Ministry of Education of China, Tianjin, 300072 People’s Republic of China
- Collaborative Innovation Center of Chemical Science and Engineering, Tianjin, People’s Republic of China
- Center for Biosafety Research and Strategy, Tianjin University, Tianjin, People’s Republic of China
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16
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Heidari F, Riahi H, Aghamiri MR, Zakeri F, Shariatmadari Z, Hauer T. 226Ra, 238U and Cd adsorption kinetics and binding capacity of two cyanobacterial strains isolated from highly radioactive springs and optimal conditions for maximal removal effects in contaminated water. INTERNATIONAL JOURNAL OF PHYTOREMEDIATION 2018; 20:369-377. [PMID: 29584468 DOI: 10.1080/15226514.2017.1393392] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Biomass-based decontamination methods are among the most interesting water treatment techniques. In this study, 2 cyanobacterial strains, Nostoc punctiforme A.S/S4 and Chroococcidiopsis thermalis S.M/S9, isolated from hot springs containing high concentrations of radium (226Ra), were studied to be associated with removal of radionuclides (238U and 226Ra) and heavy metal cadmium (Cd) from aqueous solutions. The adsorption equilibrium data was described by Langmuir and Freundlich isotherm models. Kinetic studies indicated that the sorption of 3 metals followed pseudo-second-order kinetics. Effects of biomass concentration, pH, contact time, and initial metal concentration on adsorption were also investigated. Fourier-transform infrared spectroscopy revealed active binding sites on the cyanobacterial biomass. The obtained maximum biosorption capacities were 630 mg g-1 and 37 kBq g-1 for 238U and 226Ra for N. punctiforme and 730 mg g-1 and 55 kBq g-1 for C. thermalis. These 2 strains showed maximum binding capacity 160 and 225 mg g-1, respectively for Cd adsorption. These results suggest that radioactivity resistant cyanobacteria could be employed as an efficient adsorbent for decontamination of multi-component, radioactive and industrial wastewater.
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Affiliation(s)
- Fatemeh Heidari
- a Faculty of Life Sciences and Biotechnology , Shahid Beheshti University , Evin , Tehran , Iran
| | - Hossein Riahi
- a Faculty of Life Sciences and Biotechnology , Shahid Beheshti University , Evin , Tehran , Iran
| | | | - Farideh Zakeri
- d Nuclear Science and Technology Research Institute , Tehran , Iran
| | - Zeinab Shariatmadari
- a Faculty of Life Sciences and Biotechnology , Shahid Beheshti University , Evin , Tehran , Iran
| | - Tomáš Hauer
- b Institute of Experimental Botany AS CR, Centre for Phycology , Třeboň , Czech Republic
- e Faculty of Science , University of South Bohemia , České Budějovice , Czech Republic
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17
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Etesami H. Bacterial mediated alleviation of heavy metal stress and decreased accumulation of metals in plant tissues: Mechanisms and future prospects. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2018; 147:175-191. [PMID: 28843189 DOI: 10.1016/j.ecoenv.2017.08.032] [Citation(s) in RCA: 231] [Impact Index Per Article: 38.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2017] [Revised: 07/29/2017] [Accepted: 08/14/2017] [Indexed: 05/22/2023]
Abstract
Heavy metal pollution of agricultural soils is one of main concerns causing some of the different ecological and environmental problems. Excess accumulation of these metals in soil has changed microbial community (e.g., structure, function, and diversity), deteriorated soil, decreased the growth and yield of plant, and entered into the food chain. Plants' tolerance to heavy metal stress needs to be improved in order to allow growth of crops with minimum or no accumulation of heavy metals in edible parts of plant that satisfy safe food demands for the world's rapidly increasing population. It is well known that PGPRs (plant growth-promoting rhizobacteria) enhance crop productivity and plant resistance to heavy metal stress. Many recent reports describe the application of heavy metal resistant-PGPRs to enhance agricultural yields without accumulation of metal in plant tissues. This review provides information about the mechanisms possessed by heavy metal resistant-PGPRs that ameliorate heavy metal stress to plants and decrease the accumulation of these metals in plant, and finally gives some perspectives for research on these bacteria in agriculture in the future.
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Affiliation(s)
- Hassan Etesami
- Department of Soil Science, University College of Agriculture and Natural Resources, University of Tehran, 31587-77871 Tehran, Iran.
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18
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19
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Effect of trace elements and optimization of their composition for the nitrification of a heterotrophic nitrifying bacterium, Acinetobacter harbinensis HITLi7T, at low temperature. ANN MICROBIOL 2017. [DOI: 10.1007/s13213-017-1298-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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20
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Diengdoh OL, Syiem MB, Pakshirajan K, Rai AN. Zn 2+ sequestration by Nostoc muscorum: study of thermodynamics, equilibrium isotherms, and biosorption parameters for the metal. ENVIRONMENTAL MONITORING AND ASSESSMENT 2017; 189:314. [PMID: 28589456 DOI: 10.1007/s10661-017-6013-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 05/21/2017] [Indexed: 06/07/2023]
Abstract
Microbial biosorption has evolved as an effective strategy for heavy metal removal from contaminated waters. The common cyanobacterium Nostoc muscorum isolated from the banks of a polluted river in Meghalaya, India, was tested for its potential to remove Zn2+ from aqueous solutions. Energy-dispersive X-ray (EDX) study verified Zn binding on the cyanobacterial biomass, and FTIR analysis revealed many negatively charged functional groups (hydroxyl, carbonyl, alcohol, amine, phosphoryl, sulfhydryl, and carboxyl) on the cell surface that aided in metal binding. Thermodynamic studies established the biosorption process to be energetically favorable with negative free energy change (-10.404, -10.599, and -10.796 kJ/mol at 298, 303, and 308 K, respectively). Sorption isotherm data fitted best in the Langmuir isotherm indicating monolayer nature of Zn sorption. The organism showed hyper-accumulation tendency towards Zn with a maximum sorption capacity as high as 2500 mg of Zn taken up per gram of biomass. The separation factor R L calculated from Langmuir isotherm ranged between 0 and 1 signifying favorable interaction between the cyanobacterial biomass and the Zn ions. Various experimental parameters, viz. pH, temperature, inoculum age and size, and shaking rate, influenced Zn biosorption. Optimized experimental conditions significantly enhanced the sorption percentage. Sorption was primarily a fast surface phenomenon in the beginning with internalization of zinc ions by the live cells on prolonged exposure.
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Affiliation(s)
- Omega L Diengdoh
- Department of Biochemistry, North Eastern Hill University, Shillong, Meghalaya, 793022, India
| | - Mayashree B Syiem
- Department of Biochemistry, North Eastern Hill University, Shillong, Meghalaya, 793022, India.
| | - Kannan Pakshirajan
- Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, Assam, 781039, India
| | - Amar N Rai
- Department of Biochemistry, North Eastern Hill University, Shillong, Meghalaya, 793022, India
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Ahad RIA, Goswami S, Syiem MB. Biosorption and equilibrium isotherms study of cadmium removal by Nostoc muscorum Meg 1: morphological, physiological and biochemical alterations. 3 Biotech 2017; 7:104. [PMID: 28560644 PMCID: PMC5449281 DOI: 10.1007/s13205-017-0730-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 04/10/2017] [Indexed: 11/29/2022] Open
Abstract
Rice fields of Meghalaya especially in the coal mining belt receive water contaminated by effluents from mines that are known to carry harmful heavy metal ions such as Cu, Fe, Zn, Ni, Cd, As, Pb, Cr, etc. Cd exposure was analyzed in the cyanobacterium Nostoc muscorum Meg 1 isolated from a contaminated rice field in Sohra, Meghalaya, India. Toxicity study established 0.5 ppm on day 3 to be the LD50. At LD50 chlorophyll a and total protein concentration was reduced by 50.9 and 52.5%, while nitrogenase and glutamine synthetase activities were inhibited by 40.8 and 38.4%. EDX and FTIR analyses confirmed Cd binding and participation of hydroxyl, carbonyl, carboxyl and phosphate groups in biosorption of Cd onto the cell surfaces. SEM study established morphological changes. At pH 8.0 and temperature 25 ± 2 °C, the cyanobacterium removed 92% Cd within 24 h. Of this, 91% Cd was adsorbed on the cell surface while 4% was internally accumulated. The energy required for internal accumulation of Cd was partly provided in the form of ATP synthesized during active photosynthesis. The Langmuir isotherm was found best fitted with a R 2 value 0.98 when compared to Freundlich and Temkin adsorption isotherms. The maximum sorption capacity, Q max, of the organism was 71.4 mg of Cd per g of biomass. R L value of 0.29 indicated favorable interaction between cyanobacterial biomass and Cd. The adsorption intensity, n value 7.69 g/L obtained from Freundlich isotherm showed that the organism possessed high Cd sorption capacity.
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Affiliation(s)
- Rabbul Ibne A Ahad
- Department of Biochemistry, North-Eastern Hill University, Shillong, Meghalaya, 793022, India
| | - Smita Goswami
- Department of Biochemistry, North-Eastern Hill University, Shillong, Meghalaya, 793022, India
| | - Mayashree B Syiem
- Department of Biochemistry, North-Eastern Hill University, Shillong, Meghalaya, 793022, India.
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Ni L, Li D, Su L, Xu J, Li S, Ye X, Geng H, Wang P, Li Y, Li Y, Acharya K. Effects of algae growth on cadmium remobilization and ecological risk in sediments of Taihu Lake. CHEMOSPHERE 2016; 151:37-44. [PMID: 26923240 DOI: 10.1016/j.chemosphere.2016.02.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Revised: 01/05/2016] [Accepted: 02/02/2016] [Indexed: 06/05/2023]
Abstract
Indoor simulation experiment with 2.76 L microcosms using sediment from Taihu Lake were conducted to investigate the relationship between algae bloom and heavy metals release into a lake aquatic environment. The results showed that Microcystic aeruginosa (M. aeruginosa) growth can enhance cadmium (Cd) mobilization from sediments to overlying water due to increasing pH and DO content of overlying water and changing the redox condition of surface sediment (0-2 cm) from weak oxidation to weak reduction. The dissolved Cd concentration in overlying water can be decreased during algal growth process. The remobilization of Cd from sediment can effectively reduce the ecological risk of total Cd in sediments. The results of this study showed that both Igeo and Er(i) can be used to effectively evaluate the ecological risk of heavy metal Cd in different fractions.
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Affiliation(s)
- Lixiao Ni
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, MOE, Hohai University, 210098 Nanjing, China; School of Environment, Hohai University, 210098 Nanjing, China.
| | - Dandan Li
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, MOE, Hohai University, 210098 Nanjing, China; School of Environment, Hohai University, 210098 Nanjing, China
| | - Lili Su
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, MOE, Hohai University, 210098 Nanjing, China; School of Environment, Hohai University, 210098 Nanjing, China
| | - Jiajun Xu
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, MOE, Hohai University, 210098 Nanjing, China; School of Environment, Hohai University, 210098 Nanjing, China
| | - Shiyin Li
- School of Environment, Nanjing Normal University, 210097 Nanjing, China.
| | - Xiang Ye
- Anhui Urban Construction Design & Research Institute, 230051 Hefei, China
| | - Hong Geng
- China Machinery International Engineering Design & Research Institute Co., Ltd- Eastchina Branch, 210023 Nanjing, China
| | - Peifang Wang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, MOE, Hohai University, 210098 Nanjing, China; School of Environment, Hohai University, 210098 Nanjing, China
| | - Yi Li
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, MOE, Hohai University, 210098 Nanjing, China; School of Environment, Hohai University, 210098 Nanjing, China
| | - Yiping Li
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, MOE, Hohai University, 210098 Nanjing, China; School of Environment, Hohai University, 210098 Nanjing, China
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A. Ahmed S, El-Roudi AM, Salem AA. Removal of Mn(II) from Ground Water by Solid Wastes of Sugar Industry. ACTA ACUST UNITED AC 2015. [DOI: 10.3923/jest.2015.338.351] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Goswami S, Diengdoh OL, Syiem MB, Pakshirajan K, Kiran MG. Zn(II) and Cu(II) removal byNostoc muscorum: a cyanobacterium isolated from a coal mining pit in Chiehruphi, Meghalaya, India. Can J Microbiol 2015; 61:209-15. [DOI: 10.1139/cjm-2014-0599] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Nostoc muscorum was isolated from a coal mining pit in Chiehruphi, Meghalaya, India, and its potential to remove Zn(II) and Cu(II) from media and the various biochemical alterations it undergoes during metal stress were studied. Metal uptake measured as a function of the ions removed by N. muscorum from media supplemented independently with 20 μmol/L ZnSO4and CuSO4established the ability of this cyanobacterium to remove 66% of Zn2+and 71% of Cu2+within 24 h of contact time. Metal binding on the cell surface was found to be the primary mode of uptake, followed by internalization. Within 7 days of contact, Zn2+and Cu2+mediated dissimilar effects on the organism. For instance, although chlorophyll a synthesis was increased by 12% in Zn2+-treated cells, it was reduced by 26% in Cu2+-treated cells. Total protein content remained unaltered in Zn2+-supplemented medium; however, a 15% reduction was noticed upon Cu2+exposure. Copper enhanced both photosynthesis and respiration by 15% and 19%, respectively; in contrast, photosynthesis was unchanged and respiration dropped by 11% upon Zn2+treatment. Inoculum age also influenced metal removal ability. Experiments in the presence of 3-(3,4-dichlorophenyl)-1,1-dimethylurea (a photosynthetic inhibitor), carbonyl cyanide m-chlorophenyl hydrazone (an uncoupler), and exogenous ATP established that metal uptake was energy dependent, and photosynthesis contributed significantly towards the energy pool required to mediate metal removals.
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Affiliation(s)
- Smita Goswami
- Department of Biochemistry, North-Eastern Hill University, Shillong 793022, Meghalaya, India
| | - Omega L. Diengdoh
- Department of Biochemistry, North-Eastern Hill University, Shillong 793022, Meghalaya, India
| | - Mayashree B. Syiem
- Department of Biochemistry, North-Eastern Hill University, Shillong 793022, Meghalaya, India
| | - Kannan Pakshirajan
- Department of Biotechnology, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Mothe Gopi Kiran
- Centre for the Environment, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
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Zhang J, Wang LH, Yang JC, Liu H, Dai JL. Health risk to residents and stimulation to inherent bacteria of various heavy metals in soil. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 508:29-36. [PMID: 25437950 DOI: 10.1016/j.scitotenv.2014.11.064] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Revised: 11/18/2014] [Accepted: 11/20/2014] [Indexed: 06/04/2023]
Abstract
The toxicities and effects of various metals and metalloids would be misunderstood by health risks based on their concentrations, when their effects on bacterial and ecological functions in soil are disregarded. This study investigated the concentrations and health risks of heavy metals, soil properties, and bacterial 16S rRNA gene in soil around the largest fresh water lake in North China. The health risks posed by Mn and As were higher than those of other heavy metals and metalloids. Mn, As, and C were significantly correlated with the bacterial species richness indices. According to canonical correspondence analysis, species richness was mainly affected by Mn, Pb, As, and organic matter, while species evenness was mainly affected by Mn, pH, N, C, Cd, and Pb. Covariable analysis confirmed that most effects of metals on bacterial diversity were attributed to the combined effects of metals and soil properties rather than single metals. Most bacteria detected in (almost) all soil were identified as Gammaproteobacteria. Specific bacteria belonging to Proteobacteria (Gamma, Alpha, Epsilon, and Beta), Firmicutes, Actinobacteria, Cyanobacterium, Nitrospirae, and Fusobacterium were only identified in soil with high concentrations of Mn, Pb, and As, indicating their remediation potency. Bacterial abilities and mechanisms in pollutant resistance and element cycling in the region were also discussed.
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Affiliation(s)
- Juan Zhang
- Environmental Research Institute, Shandong University, Jinan 250100, China; School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Li-Hong Wang
- Shandong Analysis and Test Center, Shandong Academy of Sciences, Jinan 250014, China
| | - Jun-Cheng Yang
- Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Hui Liu
- Environmental Research Institute, Shandong University, Jinan 250100, China
| | - Jiu-Lan Dai
- Environmental Research Institute, Shandong University, Jinan 250100, China.
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Chen L, Zhu Y, Song Z, Wang J, Zhang W. An orphan response regulator Sll0649 involved in cadmium tolerance and metal homeostasis in photosynthetic Synechocystis sp. PCC 6803. J Proteomics 2014; 103:87-102. [DOI: 10.1016/j.jprot.2014.03.029] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 03/07/2014] [Accepted: 03/23/2014] [Indexed: 10/25/2022]
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Acharya C, Apte SK. Insights into the interactions of cyanobacteria with uranium. PHOTOSYNTHESIS RESEARCH 2013; 118:83-94. [PMID: 24101170 DOI: 10.1007/s11120-013-9928-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Accepted: 09/23/2013] [Indexed: 06/02/2023]
Abstract
Due to various activities associated with nuclear industry, uranium is migrated to aquatic environments like groundwater, ponds or oceans. Uranium forms stable carbonate complexes in the oxic waters of pH 7-10 which results in a high degree of uranium mobility. Microorganisms employ various mechanisms which significantly influence the mobility and the speciation of uranium in aquatic environments. Uranyl bioremediation studies, this far, have generally focussed on low pH conditions and related to adsorption of positively charged UO2 (2+) onto negatively charged microbial surfaces. Sequestration of anionic uranium species, i.e. [UO2(CO3) 2 (2-) ] and [UO2(CO3) 3 (4-) ] onto microbial surfaces has received only scant attention. Marine cyanobacteria are effective metal adsorbents and represent an important sink for metals in aquatic environment. This article addresses the cyanobacterial interactions with toxic metals in general while stressing on uranium. It focusses on the possible mechanisms employed by cyanobacteria to sequester uranium from aqueous solutions above circumneutral pH where negatively charged uranyl carbonate complexes dominate aqueous uranium speciation. The mechanisms demonstrated by cyanobacteria are important components of biogeochemical cycle of uranium and are useful for the development of appropriate strategies, either to recover or remediate uranium from the aquatic environments.
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Affiliation(s)
- Celin Acharya
- Molecular Biology Division, Bhabha Atomic Research Centre, Trombay, Mumbai, 400 085, India,
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Gerasimenko LM, Orleanskii VK, Zaitseva LV. Accumulation and precipitation of Mn2+ by the cells of Oscillatoria terebriformis. Microbiology (Reading) 2013. [DOI: 10.1134/s0026261713050032] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Abstract
Recently the utilization of prokaryotic cells (such as bacteria, algae) and plants have emerged as novel methods for the synthesis of nanoparticles intracellularly. Therefore the applications on living organisms have recently attracted the attention of biologists towards nanobiotechnology. In the present study, Silver, Gold and bimetallic alloy Ag-Au nanoparticles were synthesized from marine red alga,Gracilaria sp.,of Gulf of Mannar with different molar concentrations of 100%Ag, 100% Au and Ag:Au (1:1, 1:3 and 3:1). The reduction of Ag, Au and Ag:Au NPs was confirmed by change of colour (i.e. from transparent to dark brown for silver NPs, to ruby red for gold NPs and pale pink for bimetallic NPs) as well as by peak absorption spectra. The absorption peak of theGracilaria sp.,for 100% Ag occurred at 419nm, for 100% Au at 536nm, for Ag: Au (1:1) concentrations at 504 nm for Ag: Au (1:3) at 526 nm and for Ag: Au (3:1) at 501nm. The size of Ag, Au and bimetallic Ag-Au NPs was measured by SEM analysis, proved that the synthesized nanoparticles were colloidal in nature. The bimetallic nanoparticles exhibited good antibacterial activity against Gram positive bacteriaStaphylococcus aureusand Gram negative bacteriaKlebsiella pneumoniae. The above results revealed thatSalmonella typhiiandEscherichia colihave no activity. However, bimetallic NPs of 1:3 concentration showed zones of inhibition against the pathogenic bacteria such asStaphylococcus aureusandKlebsiella pneumoniaerather than Ag NPs and Au NPs. This process of the nanoparticles production is eco-friendly as it is free from any solvent or toxic chemicals, and is also easily amenable for large-scale production.
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Hasan HA, Abdullah SRS, Kofli NT, Kamarudin SK. Isotherm equilibria of Mn²⁺ biosorption in drinking water treatment by locally isolated Bacillus species and sewage activated sludge. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2012; 111:34-43. [PMID: 22813857 DOI: 10.1016/j.jenvman.2012.06.027] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2010] [Revised: 06/12/2012] [Accepted: 06/18/2012] [Indexed: 06/01/2023]
Abstract
Manganese (Mn(2+)) is one of the inorganic contaminant that causes problem to water treatment and water distribution due to the accumulation on water piping systems. In this study, Bacillus sp. and sewage activated sludge (SAS) were investigated as biosorbents in laboratory-scale experiments. The study showed that Bacillus sp. was a more effective biosorbent than SAS. The experimental data were fitted to the Langmuir (Langmuir-1 & Langmuir-2), Freundlich, Temkin, Dubinin-Radushkevich (D-R) and Redlich-Peterson (R-P) isotherms to obtain the characteristic parameters of each model. Mn(2+) biosorption by Bacillus sp. was found to be significantly better fitted to the Langmuir-1 isotherm than the other isotherms, while the D-R isotherm was the best fit for SAS; i.e., the χ(2) value was smaller than that for the Freundlich, Temkin, and R-P isotherms. According to the evaluation using the Langmuir-1 isotherm, the maximum biosorption capacities of Mn(2+) onto Bacillus sp. and SAS were 43.5 mg Mn(2+)/g biomass and 12.7 mg Mn(2+)/g biomass, respectively. The data fitted using the D-R isotherm showed that the Mn(2+) biosorption processes by both Bacillus sp. and SAS occurred via the chemical ion-exchange mechanism between the functional groups and Mn(2+) ion.
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Affiliation(s)
- Hassimi Abu Hasan
- Department of Chemical and Process Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia.
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Exopolysaccharide-producing cyanobacteria in heavy metal removal from water: molecular basis and practical applicability of the biosorption process. Appl Microbiol Biotechnol 2011; 92:697-708. [DOI: 10.1007/s00253-011-3601-z] [Citation(s) in RCA: 143] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Revised: 09/05/2011] [Accepted: 09/20/2011] [Indexed: 10/17/2022]
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Abstract
Biosorption has been developed as an effective and economic method to treat wastewater containing low concentrations of metal pollutants. In this study, a bacterium, Citrobacter freudii, was used as a biosorbent to adsorb uraniumions. The factors which influence the adsorption of uranium by Citrobacter freudii were investigated, including pH, the strain dosage and the initial concentrate of uranium. The results showed that the adsorption efficiency increased with the increased of pH in the beginning of the adsorption and reached its maximum at pH 6; when the strain dosage and the initial concentrate of uranium were 6.0g/L and 20mg/L, respectively, the adsorption efficiency reached 93.89% and 94.68%, respectively. The authors investigated the active sites of bacteria for biosorption and the results proved that carboxyl in the cell wall played an important role in biosorption.
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Hasan H, Abdullah S, Kofli N, Kamaruddin S. Biosorption of Manganese in Drinking Water by Isolated Bacteria. ACTA ACUST UNITED AC 2010. [DOI: 10.3923/jas.2010.2653.2657] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Oberholster PJ, Myburgh JG, Ashton PJ, Botha AM. Responses of phytoplankton upon exposure to a mixture of acid mine drainage and high levels of nutrient pollution in Lake Loskop, South Africa. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2010; 73:326-335. [PMID: 19896711 DOI: 10.1016/j.ecoenv.2009.08.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2009] [Revised: 07/07/2009] [Accepted: 08/17/2009] [Indexed: 05/28/2023]
Abstract
The relationships between water quality and the phytoplankton community within Lake Loskop were studied during the late summer and autumn of 2008 to evaluate the impacts of acid mine drainage and high nutrient concentrations. The higher concentrations of metal ions and sulphate had adverse effects on certain phytoplankton species in the inflowing riverine zone of Lake Loskop, in comparison to the reference site in the lacustrine zone of the lake, which was dominated by the larger and slower growing late summer species of Coelastrum reticulum Nägeli, Straurastrum anatinum Meyen ex Ralfs and Ceratium hirundinella Müller. The high nutrient concentrations (nitrogen: 17 mg l(-1) and orthophosphate: 0.7 mg l(-1)) during the mid-summer peak of the rainy season were associated with the development of a bloom of the cyanobacterium Microcystis. Water quality data associated with the development of the Microcystis bloom suggest that the aquatic system of Lake Loskop has now entered an alternate, hypertrophic regime. This change overshadowed the adverse effects of high concentrations of heavy metal ions and low pH. Throughout this study, the reference site in the lacustrine zone of Lake Loskop had lower concentrations of metal ions and sulphate, and higher pH values. The response of phytoplankton bioassays on integrated water samples from the different sampling sites did provide potential answers to the reasons for the absence of the algal group Chlorophyceae in the phytoplankton community structure in the riverine zone of the lake.
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Affiliation(s)
- P J Oberholster
- CSIR Natural Resources and the Environment, P.O. Box 395, Pretoria 0001, South Africa.
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Baptista MS, Vasconcelos MT. Cyanobacteria Metal Interactions: Requirements, Toxicity, and Ecological Implications. Crit Rev Microbiol 2008; 32:127-37. [PMID: 16893750 DOI: 10.1080/10408410600822934] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The environmental health-related relevance of cyanobacteria is primarily related to their ability to produce a wide range of toxins, which are known to be hazardous to many organisms, including human beings. The occurrence of cyanobacterial blooms has been related to eutrophic surface water. In the bloom-forming process the levels of phosphorus and nitrogen have been well documented but information regarding concentrations of other chemicals (inorganic, organo-metallic, and organic) is still incipient. Several contaminants, like trace metals, elicit a variety of acute and chronic toxicity effects, but cyanobacteria also have the capability to accumulate, detoxify, or metabolize such substances, to some extent. The role of cyanobacterial exudates has been proved a means of both nutrient acquisition and detoxification. In addition, cyanobacteria are effective biological metal sorbents, representing an important sink for metals in aquatic environment. Understanding the fundamental physicochemical mechanisms of trace metal bio-uptake by cyanobacteria in natural systems is a step towards identifying under what conditions cyanobacterial growth is favored and to ascertain the mechanisms by which blooms (and toxin production) are triggered. In this review the cyanobacterial interactions with metals will be discussed, focusing on freshwater systems.
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Affiliation(s)
- Mafalda S Baptista
- Chemistry Department, Faculty of Sciences, University of Porto, Porto, Portugal.
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Dasgupta J, Ananyev GM, Dismukes GC. Photoassembly of the Water-Oxidizing Complex in Photosystem II. Coord Chem Rev 2008; 252:347-360. [PMID: 19190725 DOI: 10.1016/j.ccr.2007.08.022] [Citation(s) in RCA: 140] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The light-driven steps in the biogenesis and repair of the inorganic core comprising the O(2)-evolving center of oxygenic photosynthesis (photosystem II water-oxidation complex, PSII-WOC) are reviewed. These steps, known collectively as photoactivation, involve the photoassembly of the free inorganic cofactors to the cofactor-depleted PSII-(apo-WOC) driven by light and produce the active O(2)-evolving core comprised of Mn(4)CaO(x)Cl(y). We focus on the functional role of the inorganic components as seen through the competition with non-native cofactors ("inorganic mutants") on water oxidation activity, the rate of the photoassembly reaction, and on structural insights gained from EPR spectroscopy of trapped intermediates formed in the initial steps of the assembly reaction. A chemical mechanism for the initial steps in photoactivation is given that is based on these data. Photoactivation experiments offer the powerful insights gained from replacement of the native cofactors, which together with the recent X-ray structural data for the resting holoenzyme provide a deeper understanding of the chemistry of water oxidation. We also review some new directions in research that photoactivation studies have inspired that look at the evolutionary history of this remarkable catalyst.
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Affiliation(s)
- Jyotishman Dasgupta
- 306 Lewis Hall, Department of Chemistry, University of California, Berkeley, CA 94709, USA
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Energy from photobioreactors: Bioencapsulation of photosynthetically active molecules, organelles, and whole cells within biologically inert matrices. PURE APPL CHEM 2008. [DOI: 10.1351/pac200880112345] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Photosynthesis is a highly efficient solar energy transformation process. Exploiting this natural phenomenon is one way to overcome the shortage in the Earth’s fuel resources. This review summarizes the work carried out in the field of photobioreactor design via the immobilization of photosynthetically active matter within biologically inert matrices and the potential biotechnological applications of the obtained hybrid materials within the domain of solar energy to chemical energy transformation. The first part deals with the design of artificial photosynthetic reaction centers (RCs) by the encapsulation of pigments, proteins, and complexes. The action of thylakoids, chloroplasts, and whole plant cells, immobilized in biocompatible supports, in the conversion of CO2 into chemical energy, is also addressed. Finally, the latest advances in the exploitation of the bioactivity of photosynthetically active micro-organisms are explored in terms of the production of secondary metabolites and hydrogen.
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Rooke JC, Léonard A, Su BL. Targeting photobioreactors: Immobilisation of cyanobacteria within porous silica gel using biocompatible methods. ACTA ACUST UNITED AC 2008. [DOI: 10.1039/b717990a] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Xie S, Yang J, Chen C, Zhang X, Wang Q, Zhang C. Study on biosorption kinetics and thermodynamics of uranium by Citrobacter freudii. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2008; 99:126-33. [PMID: 17765369 DOI: 10.1016/j.jenvrad.2007.07.003] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2007] [Revised: 06/30/2007] [Accepted: 07/09/2007] [Indexed: 05/17/2023]
Abstract
Biosorption has been developed as an effective and economic method to treat wastewater containing low concentrations of metal pollutants. In this study, a bacterium, Citrobacter freudii, was used as a biosorbent to adsorb uranium ions. The thermodynamics and kinetics of this adsorption, as well as its mechanism, were investigated. The results indicated that the biosorption rate could be better described by a pseudo 2nd-order model than a pseudo 1st-order model. The adsorption of U (VI) proceeded very rapidly in the first 30min and subsequently slowed down continuously for a long period. The biosorption isotherm of uranium by C. freudii could be described well by the Langmuir or Freundlich isotherm, and the latter was better. The thermodynamics parameters, DeltaH degrees , DeltaG degrees , and DeltaS degrees were calculated according to the results of the experiment, which showed this biosorption as being endothermic and spontaneous. The authors investigated the active sites of bacteria for biosorption and the results proved that carboxyl in the cell wall played an important role in biosorption.
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Affiliation(s)
- Shuibo Xie
- Department of Environment Science and Engineering, Tsinghua University, Beijing 100084, P R China.
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41
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Bioaccumulation and biosorption of stable strontium and 90Sr by Oscillatoria homogenea cyanobacterium. J Radioanal Nucl Chem 2007. [DOI: 10.1007/s10967-006-6785-4] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Raungsomboon S, Chidthaisong A, Bunnag B, Inthorn D, Harvey NW. Production, composition and Pb2+ adsorption characteristics of capsular polysaccharides extracted from a cyanobacterium Gloeocapsa gelatinosa. WATER RESEARCH 2006; 40:3759-66. [PMID: 17052742 DOI: 10.1016/j.watres.2006.08.013] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2005] [Revised: 08/08/2006] [Accepted: 08/22/2006] [Indexed: 05/12/2023]
Abstract
Pb2+ adsorption by the living cells of the cyanobacterium Gloeocapsa gelatinosa was studied. Cyanobacterial cells with intact capsular polysaccharide (CPS) showed 5.7 times higher Pb adsorption capacity than that of cells without CPS. The adsorbed Pb was desorbed by EDTA, indicating that Pb2+ adsorption occurred mainly on cell surface. Production, sugar content and ability of CPS to remove Pb2+ were then studied in details. CPS production by G. gelatinosa increased when culture time was prolonged. The maximum CPS production was 35.43 mg g(-1) dry weight after 30-day cultivation. Xylose, arabinose, ribose, rhamnose, galactose, glucose, mannose and fructose were the neutral sugars presented in CPS of G. gelatinosa. Acidic sugars including galacturonic and glucuronic acids were also found in CPS. The amount and composition of G. gelatinosa's CPS varied according to its growth phase and culture conditions. The highest amount of acidic sugars was produced when cultured under low light intensity. The extracted CPS rapidly removed Pb2+ from the solution (82.22+/-4.82 mg Pb2+ per g CPS), directly demonstrating its roles in binding Pb2+ ions. Its ability to remove Pb2+ rapidly and efficiently, to grow under sub-optimal conditions (such as low pH and low light intensity), and to produce high amount of CPS with acidic sugars, leads us to conclude that G. gelatinosa is a potential viable bioadsorber for mildly acidic water contaminated with Pb2+.
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Affiliation(s)
- Suneerat Raungsomboon
- Joint Graduate School of Energy and Environment, King Mongkut's University of Technology Thonburi, 126 Pracha-Uthit Road, Bangkok 10140, Thailand
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Parvathi K, Naresh Kumar R, Nagendran R. Biosorption of manganese by Aspergillus niger and Saccharomyces cerevisiae. World J Microbiol Biotechnol 2006. [DOI: 10.1007/s11274-006-9281-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Buccolieri A, Italiano F, Dell'Atti A, Buccolieri G, Giotta L, Agostiano A, Milano F, Trotta M. Testing the photosynthetic bacterium Rhodobacter sphaeroides as heavy metal removal tool. ACTA ACUST UNITED AC 2006; 96:195-203. [PMID: 16836253 DOI: 10.1002/adic.200690019] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We present some preliminary results relevant to the ability of the purple non-sulphur bacterium Rhodobacter sphaeroides strain R26.1 to sequester heavy metals from contaminated growth media. The microorganism was chosen because of its significant tolerance to relatively high concentrations of the investigated ions Ni2+, Co2+, CrO4(2-), and MoO4(2-). In this paper the optimized conditions for the bacterial growth and the sample preparation used to infer the ability of the microorganism to cope with metal pollutants are presented. Elemental analysis has been performed by inductively coupled plasma atomic emission spectrometry previous mineralization of samples by a microwave system.
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Affiliation(s)
- Alessandro Buccolieri
- Dipartimento di Scienza dei Materiali, Università degli Studi di Lecce, via per Arnesano, 73100 Lecce, Italy
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Lengke MF, Fleet ME, Southam G. Synthesis of platinum nanoparticles by reaction of filamentous cyanobacteria with platinum(IV)-chloride complex. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2006; 22:7318-23. [PMID: 16893232 DOI: 10.1021/la060873s] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Interaction of cyanobacteria (Plectonema boryanum UTEX 485) with aqueous platinum(IV)-chloride (PtCl(4) degrees ) has been investigated at 25-100 degrees C for up to 28 days, and 180 degrees C for 1 day. The addition of PtCl(4) degrees to the cyanobacteria culture initially promoted the precipitation of Pt(II)-organic material as amorphous spherical nanoparticles (< or =0.3 microm) in solutions and dispersed nanoparticles within bacterial cells. The spherical Pt(II)-organic nanoparticles were connected into long beadlike chains by a continuous coating of organic material derived from the cyanobacterial cells, and aged to nanoparticles of crystalline platinum metal with increase in temperature and reaction time. The stepwise reduction for the formation of platinum nanoparticles in the presence of cyanobacteria was deduced to be Pt(IV) [PtCl(4) degrees ] --> Pt(II) [Pt(II)-organics] --> Pt(0). Spherical platinum-bearing nanoparticles were not present in abiotic PtCl(4) degrees experiments conducted under similar conditions and duration.
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Affiliation(s)
- Maggy F Lengke
- Department of Earth Sciences, University of Western Ontario, London, Ontario, N6A 5B7, Canada.
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Sas KN, Kovács L, Zsíros O, Gombos Z, Garab G, Hemmingsen L, Danielsen E. Fast cadmium inhibition of photosynthesis in cyanobacteria in vivo and in vitro studies using perturbed angular correlation of γ-rays. J Biol Inorg Chem 2006; 11:725-34. [PMID: 16821039 DOI: 10.1007/s00775-006-0113-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2005] [Accepted: 04/26/2006] [Indexed: 11/28/2022]
Abstract
The effect of cadmium on the photosynthetic activity of Synechocystis PCC 6803 was monitored in this study. The oxygen evolving capacity of Synechocystis treated with 40 muM CdCl(2) was depressed to 10% of the maximum in 15 min, indicating that Cd(2+) penetrated rapidly into the cells and blocked the photosynthetic activity. However, neither photosystem II (PSII) nor photosystem I (PSI) activity showed a significant short-term decrease which would explain this fast decrease in the whole-chain electron transport. Thermoluminescence measurements have shown that the charge separation and stabilization in PSII remains essentially unchanged during the first few hours following the Cd(2+) treatment. The electron flow through PSI was monitored by following the redox changes of the P700 reaction centers of PSI. Alterations in the oxidation kinetics of P700 in the Cd(2+)-treated cells indicated that Cd(2+) treatment might affect the available electron acceptor pool of P700, including the CO(2) reduction and accumulation in the cells. Perturbed angular correlation of gamma-rays (PAC) using the radioactive (111m)Cd isotope was used to follow the Cd(2+) uptake at a molecular level. The most plausible interpretation of the PAC data is that Cd(2+) is taken up by one or more Zn proteins replacing Zn(2+) in Synechocystis PCC 6803. Using the radioactive (109)Cd isotope, a protein of approximately 30 kDa that binds Cd(2+) could be observed in sodium dodecyl sulfate polyacrylamide gel electrophoresis. The results indicate that Cd(2+) might inactivate different metal-containing enzymes, including carbonic anhydrase, by replacing the zinc ion, which would explain the rapid and almost full inhibition of the photosynthetic activity in cyanobacteria.
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Affiliation(s)
- Klára Nárcisz Sas
- Department of Natural Sciences, Royal Veterinary and Agricultural University, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark.
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Giotta L, Agostiano A, Italiano F, Milano F, Trotta M. Heavy metal ion influence on the photosynthetic growth of Rhodobacter sphaeroides. CHEMOSPHERE 2006; 62:1490-9. [PMID: 16081134 DOI: 10.1016/j.chemosphere.2005.06.014] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2005] [Revised: 05/31/2005] [Accepted: 06/12/2005] [Indexed: 05/03/2023]
Abstract
The potential of purple non-sulphur bacteria for bioremediation was assessed by investigating the ability of Rhodobacter sphaeroides strain R26.1 to grow photosynthetically in heavy metal contaminated environments. Bacterial cultures were carried out in artificially polluted media, enriched with the transition metal ions Hg2+, Cu2+, Fe2+, Ni2+, Co2+, MoO4(2-), and CrO4(2-) in millimolar concentration range. For each investigated ion the effect on growth parameters was evaluated. The analysis of concentration-effect curves revealed a differentiated response, indicating that diverse mechanisms of tolerance and/or resistance are involved. Adaptation or selection procedures were not applied, leading to assess intrinsic abilities of coping with these contaminants. The microorganism proved to be highly tolerant to heavy metal exposure, especially towards Co2+, Fe2+ and MoO4(2-). In addition Ni2+ and Co2+ were found to decrease the cellular content of light harvesting complexes. A characteristic behavior was observed with mercuric ions, which produced a significant increase of the lag-phase.
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Affiliation(s)
- Livia Giotta
- Dipartimento di Scienza dei Materiali, Università degli Studi di Lecce, strada per Arnesano, 73100 Lecce, Italy.
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Kassab DM, Roane TM. Differential responses of a mine tailings Pseudomonas isolate to cadmium and lead exposures. Biodegradation 2006; 17:379-87. [PMID: 16477362 DOI: 10.1007/s10532-005-9010-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2005] [Accepted: 08/04/2005] [Indexed: 10/25/2022]
Abstract
We examined cadmium and lead resistance in Pseudomonas sp. S8A, an isolate obtained from mine tailings-contaminated soil. Resistant to soluble metal concentrations up to 200 mg l(-1) cadmium and 300 mg l(-1) lead, S8A produced both exopolymer and biosurfactant. Upon growth, this pseudomonad diverged into two morphologically distinct colony subtypes; small and round or large and flat. In the presence of lead and in the no metal control the large morphotype appeared only in late stationary phase. With cadmium the large morphotype appeared immediately following exposure. Results show that the large morphotype produced greater amounts of surfactant than the small morphotype, suggesting a unique subpopulation response to cadmium toxicity. Results also indicate that an unidentified 28 kDa protein was expressed following exposure to >10 mg l(-1) cadmium. This study demonstrates new links between surfactant production, differential subpopulation response and metal exposure.
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Affiliation(s)
- Duried M Kassab
- Department of Biology, University of Colorado at Denver, Denver, USA
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Song T, Mårtensson L, Eriksson T, Zheng W, Rasmussen U. Biodiversity and seasonal variation of the cyanobacterial assemblage in a rice paddy field in Fujian, China. FEMS Microbiol Ecol 2005; 54:131-40. [PMID: 16329979 DOI: 10.1016/j.femsec.2005.03.008] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2004] [Revised: 03/09/2005] [Accepted: 03/16/2005] [Indexed: 10/25/2022] Open
Abstract
Cyanobacteria are one of the main components of the microbiota in rice paddy fields and significantly contribute to its fertilization. The diversity and changes of the cyanobacterial assemblage were investigated during a rice growth season and after harvest in a paddy field located in Fujian Province, China. The cyanobacterial populations were analyzed by a semi-nested PCR, followed by denaturing gradient gel electrophoresis analysis. Twenty-four phylotypes were identified from the denaturing gradient gel electrophoresis profiles. The number of cyanobacterial phylotypes showed a seasonal variation and reached a peak in September, both in the upper (0-5 cm) and the deeper (10-15 cm) soil fractions. Some cyanobacterial sequences were only present during the rice growth season, while others were only found after harvest.
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Affiliation(s)
- Tieying Song
- Biotechnology Center, Fujian Academy of Agricultural Sciences, Fuzhou, PR China
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Yee N, Benning LG, Phoenix VR, Ferris FG. Characterization of metal-cyanobacteria sorption reactions: a combined macroscopic and infrared spectroscopic investigation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2004; 38:775-82. [PMID: 14968864 DOI: 10.1021/es0346680] [Citation(s) in RCA: 180] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
In this study, we conducted synchrotron radiation Fourier transform infrared (IR) spectroscopy, potentiometric titration, and metal sorption experiments to characterize metal-cyanobacteria sorption reactions. Infrared spectra were collected with samples in solution for intact cyanobacterial filaments and separated exopolymeric sheath material to examine the deprotonation reactions of cell surface functional groups. The infrared spectra of intact cells sequentially titrated from pH 3.2 to 6.5 display an increase in peak intensity and area at 1400 cm(-1) corresponding to vibrational COO- frequencies from the formation of deprotonated carboxyl surface sites. Similarly, bulk acid-base titration of cyanobacterial filaments and sheath material indicates that the concentration of proton-active surface sites is higher on the cell wall compared to the overlying sheath. A three-site model provides an excellent fit to the titration curves of both intact cells and sheath material with corresponding pKa values of 4.7 +/- 0.4, 6.6 +/- 0.2, 9.2 +/- 0.3 and 4.8 +/- 0.3, 6.5 +/- 0.1, 8.7 +/- 0.2, respectively. Finally, Cu2+, Cd2+, and Pb2+ sorption experiments were conducted as a function of pH, and a site-specific surface complexation model was used to describe the metal sorption data. The modeling indicates that metal ions are partitioned between the exopolymer sheath and cell wall and that the carboxyl groups on the cyanobacterial cell wall are the dominant sink for metals at near neutral pH. These results demonstrate that the cyanobacterial surfaces are complex structures which contain distinct surface layers, each with unique molecular functional groups and metal binding properties.
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Affiliation(s)
- Nathan Yee
- School of Earth Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom.
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