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Phosphate limitation intensifies negative effects of ocean acidification on globally important nitrogen fixing cyanobacterium. Nat Commun 2022; 13:6730. [PMID: 36344528 PMCID: PMC9640675 DOI: 10.1038/s41467-022-34586-x] [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: 11/23/2021] [Accepted: 10/28/2022] [Indexed: 11/11/2022] Open
Abstract
Growth of the prominent nitrogen-fixing cyanobacterium Trichodesmium is often limited by phosphorus availability in the ocean. How nitrogen fixation by phosphorus-limited Trichodesmium may respond to ocean acidification remains poorly understood. Here, we use phosphate-limited chemostat experiments to show that acidification enhanced phosphorus demands and decreased phosphorus-specific nitrogen fixation rates in Trichodesmium. The increased phosphorus requirements were attributed primarily to elevated cellular polyphosphate contents, likely for maintaining cytosolic pH homeostasis in response to acidification. Alongside the accumulation of polyphosphate, decreased NADP(H):NAD(H) ratios and impaired chlorophyll synthesis and energy production were observed under acidified conditions. Consequently, the negative effects of acidification were amplified compared to those demonstrated previously under phosphorus sufficiency. Estimating the potential implications of this finding, using outputs from the Community Earth System Model, predicts that acidification and dissolved inorganic and organic phosphorus stress could synergistically cause an appreciable decrease in global Trichodesmium nitrogen fixation by 2100.
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Multiple surface interaction mechanisms direct the anchoring, co-aggregation and formation of dual-species biofilm between Candida albicans and Helicobacter pylori. J Adv Res 2022; 35:169-185. [PMID: 35024198 PMCID: PMC8721356 DOI: 10.1016/j.jare.2021.03.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 03/23/2021] [Accepted: 03/29/2021] [Indexed: 12/20/2022] Open
Abstract
Introduction Polymicrobial biofilms have a significant impact on pathogenesis of infectious microorganisms. Many human diseases are affected by colonization of multi-species communities affecting negatively the treatments and increase the risks for the health. In particular, in the epithelium of the stomach co-existence between C. albicans and H. pylori has been described, which has been associated to a synergistic effect on ulcer pathogenesis. Objective The objective of this work was to advance in the understanding of surface interaction between H. pylori and C. albicans for the formation of polymicrobial biofilms. Methods Studies of microbial surfaces both bacterium, yeast and co-cultures of them were carried out by infrared spectroscopy, deconvolution analysis, transmission and scanning electron microscopies, and optic microscopy. Additional methods were used to contrast the results as dynamic light scattering, contact angle, agarose gel electrophoresis and gene amplification. Results Several surface interaction mechanisms promote the anchoring of H. pylori on C. albicans, cell co-aggregation, and polymicrobial biofilm formation, main identified interactions were: (i) hydrophobic interactions between non-polar peptide chains and lipid structures, characterized by θw among 84.9 ± 1.6 (γ = 22.78 mJ/m2 with 95.3 of dispersive contribution) and 76.6 ± 3.8 (γ = 17.34 mJ/m2, 40.2 of dispersive contribution) for C. albicans and H. pylori, respectively, (ii) hydrogen bonds between surface components of yeast and bacterium (e.g., -S-H⋅⋅⋅NH2- or -S-H⋅⋅⋅O[bond, double bond]CO-) and (iii) thiol-mediated surface interactions identified by displacements to lower wavenumbers (Δv = 5 cm-1). Evidence of internalization and electrostatic interactions were not evidenced. All observations were congruent with the biofilm formation, including the identification of small-size biostructures (i.e., 122-459 nm) associated with extracellular proteins, extracellular DNA, or outer membrane vesicles were observed characteristic of biofilm formation. Conclusion It is concluded that biofilm is formed by co-aggregation after anchoring of H. pylori on C. albicans. Several surface interactions were associated with the prevalence of H. pylori, the possibility to find C. albicans in the stomach epithelium infected by H. pylori, but also, strength interactions could be interfering in experimental observations associated with bacterial-DNA detection in culture mixtures.
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Dzurendova S, Zimmermann B, Kohler A, Reitzel K, Nielsen UG, Dupuy--Galet BX, Leivers S, Horn SJ, Shapaval V. Calcium Affects Polyphosphate and Lipid Accumulation in Mucoromycota Fungi. J Fungi (Basel) 2021; 7:jof7040300. [PMID: 33920847 PMCID: PMC8071181 DOI: 10.3390/jof7040300] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 04/08/2021] [Accepted: 04/12/2021] [Indexed: 12/11/2022] Open
Abstract
Calcium controls important processes in fungal metabolism, such as hyphae growth, cell wall synthesis, and stress tolerance. Recently, it was reported that calcium affects polyphosphate and lipid accumulation in fungi. The purpose of this study was to assess the effect of calcium on the accumulation of lipids and polyphosphate for six oleaginous Mucoromycota fungi grown under different phosphorus/pH conditions. A Duetz microtiter plate system (Duetz MTPS) was used for the cultivation. The compositional profile of the microbial biomass was recorded using Fourier-transform infrared spectroscopy, the high throughput screening extension (FTIR-HTS). Lipid content and fatty acid profiles were determined using gas chromatography (GC). Cellular phosphorus was determined using assay-based UV-Vis spectroscopy, and accumulated phosphates were characterized using solid-state 31P nuclear magnetic resonance spectroscopy. Glucose consumption was estimated by FTIR-attenuated total reflection (FTIR-ATR). Overall, the data indicated that calcium availability enhances polyphosphate accumulation in Mucoromycota fungi, while calcium deficiency increases lipid production, especially under acidic conditions (pH 2-3) caused by the phosphorus limitation. In addition, it was observed that under acidic conditions, calcium deficiency leads to increase in carotenoid production. It can be concluded that calcium availability can be used as an optimization parameter in fungal fermentation processes to enhance the production of lipids or polyphosphates.
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Affiliation(s)
- Simona Dzurendova
- Faculty of Science and Technology, Norwegian University of Life Sciences, Drøbakveien 31, 1433 Ås, Norway; (B.Z.); (A.K.); (B.X.D.--G.); (V.S.)
- Correspondence: or
| | - Boris Zimmermann
- Faculty of Science and Technology, Norwegian University of Life Sciences, Drøbakveien 31, 1433 Ås, Norway; (B.Z.); (A.K.); (B.X.D.--G.); (V.S.)
| | - Achim Kohler
- Faculty of Science and Technology, Norwegian University of Life Sciences, Drøbakveien 31, 1433 Ås, Norway; (B.Z.); (A.K.); (B.X.D.--G.); (V.S.)
| | - Kasper Reitzel
- Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark;
| | - Ulla Gro Nielsen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark;
| | - Benjamin Xavier Dupuy--Galet
- Faculty of Science and Technology, Norwegian University of Life Sciences, Drøbakveien 31, 1433 Ås, Norway; (B.Z.); (A.K.); (B.X.D.--G.); (V.S.)
| | - Shaun Leivers
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Christian Magnus Falsens vei 1, 1433 Ås, Norway; (S.L.); (S.J.H.)
| | - Svein Jarle Horn
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Christian Magnus Falsens vei 1, 1433 Ås, Norway; (S.L.); (S.J.H.)
| | - Volha Shapaval
- Faculty of Science and Technology, Norwegian University of Life Sciences, Drøbakveien 31, 1433 Ås, Norway; (B.Z.); (A.K.); (B.X.D.--G.); (V.S.)
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Zhang X, Liu Y, Li ZR, Zhang J, Chen Y, Wang Q. Impact of COD/N on anammox granular sludge with different biological carriers. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 728:138557. [PMID: 32361109 DOI: 10.1016/j.scitotenv.2020.138557] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 04/06/2020] [Accepted: 04/06/2020] [Indexed: 06/11/2023]
Abstract
The purpose of this study is to investigate the effect of COD/N interference on mature anammox granular sludge formed by different biological carriers. Three anammox granular sludge rectors were established with no biological carriers (R1), GAC (R2) and PVA-gel bead (R3), respectively. As the COD/N ratio increased to 1:2, the activity of anaerobic ammonia oxidizing bacteria in R1 and R2 was significantly inhibited. However, the nitrogen removal effect of R3 did not decrease dramatically, and the nitrogen removal rate in this phase was 1.54 ± 0.05 kg N/m3·d. As the COD/N ratio increased to 1:1.5, the removal of NH4+-N in all reactors gradually decreased. The order of COD resistance of the three reactors in this study was R3 > R2 > R1. It was found that Candidatus Brocadia might be sensitive to the presence of organic matter. The abundance of heterotrophic denitrifying bacteria increased gradually in each reactor under increased influent COD/N ratios.
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Affiliation(s)
- Xinying Zhang
- Fujian Provincial Engineering Research Center of Rural Waste Recycling Technology, College of Environment and Resources, Fuzhou University, Fuzhou 350108, China.
| | - Yang Liu
- Fujian Provincial Engineering Research Center of Rural Waste Recycling Technology, College of Environment and Resources, Fuzhou University, Fuzhou 350108, China
| | - Zong Ren Li
- Fujian Provincial Engineering Research Center of Rural Waste Recycling Technology, College of Environment and Resources, Fuzhou University, Fuzhou 350108, China
| | - Jian Zhang
- Fujian Provincial Academy of Environmental Science, Fuzhou 350003, China
| | - Yiming Chen
- Fujian Provincial Academy of Environmental Science, Fuzhou 350003, China
| | - Qiaoying Wang
- College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
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Kubincová A, Hünenberger PH, Krishnan M. Interfacial solvation can explain attraction between like-charged objects in aqueous solution. J Chem Phys 2020; 152:104713. [PMID: 32171222 DOI: 10.1063/1.5141346] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Over the past few decades, the experimental literature has consistently reported observations of attraction between like-charged colloidal particles and macromolecules in aqueous solution. Examples include nucleic acids and colloidal particles in the bulk solution and under confinement, and biological liquid-liquid phase separation. This observation is at odds with the intuitive expectation of an interparticle repulsion that decays monotonically with distance. Although attraction between like-charged particles can be rationalized theoretically in the strong-coupling regime, e.g., in the presence of multivalent counterions, recurring accounts of long-range attraction in aqueous solution containing monovalent ions at low ionic strength have posed an open conundrum. Here, we show that the behavior of molecular water at an interface-traditionally disregarded in the continuum electrostatics picture-provides a mechanism to explain the attraction between like-charged objects in a broad spectrum of experiments. This basic principle will have important ramifications in the ongoing quest to better understand intermolecular interactions in solution.
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Affiliation(s)
- Alžbeta Kubincová
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 2, CH-8093 Zürich, Switzerland
| | - Philippe H Hünenberger
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 2, CH-8093 Zürich, Switzerland
| | - Madhavi Krishnan
- Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom
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Christ JJ, Willbold S, Blank LM. Methods for the Analysis of Polyphosphate in the Life Sciences. Anal Chem 2020; 92:4167-4176. [PMID: 32039586 DOI: 10.1021/acs.analchem.9b05144] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Inorganic polyphosphate (polyP) is the polymer of orthophosphate and can be found in all living organisms. For polyP characterization, one or more of six parameters are of interest: the molecular structure (linear, cyclic, or branched), the concentration, the average chain length, the chain length distribution, the cellular localization, and the cation composition. Here, the merits, limitations, and critical parameters of the state-of-the-art methods for the analysis of the six parameters from the life sciences are discussed. With this contribution, we aim to lower the entry barrier into the analytics of polyP, a molecule with prominent, yet often incompletely understood, contributions to cellular function.
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Affiliation(s)
- Jonas Johannes Christ
- Institute of Applied Microbiology-iAMB, Aachen Biology and Biotechnology-ABBt, Worringer Weg 1, RWTH Aachen University, D-52074 Aachen, Germany
| | - Sabine Willbold
- Central Institute for Engineering, Electronics and Analytics, Analytics (ZEA-3), Wilhelm-Johnen-Straße, D-52428 Jülich, Germany
| | - Lars Mathias Blank
- Institute of Applied Microbiology-iAMB, Aachen Biology and Biotechnology-ABBt, Worringer Weg 1, RWTH Aachen University, D-52074 Aachen, Germany
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Chen H, Cheng Y, Meng D, Xue G, Jiang M, Li X. Joint effect of triclosan and copper nanoparticles on wastewater biological nutrient removal. ENVIRONMENTAL TECHNOLOGY 2018; 39:2447-2456. [PMID: 28707517 DOI: 10.1080/09593330.2017.1355937] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 07/11/2017] [Indexed: 06/07/2023]
Abstract
Triclosan (TCS) is widely used in household and personal care products, and its release into wastewater might have impact on wastewater biological treatment for its antibacterial property. Besides, emerging pollutant such as copper nanoparticles (CuNPs) will also release from nanoparticle-containing products, showing a joint effect with TCS on biological nutrient removal. The TCS of 1 and 10 mg/L inhibited the nitrosification and nitrification stage, and the first step of denitrification was suppressed as well, causing a decline in final TN removal efficiency. Additionally, the phosphorus uptake was inhibited seriously, leading to a remarkable decrease in phosphorus removal efficiency. When they were co-existed, the TCS concentration decreased due to the absorption by CuNPs, and the released Cu2+ from CuNPs increased. Further investigation revealed that when 5 mg/L CuNPs and 1 mg/L TCS were immediately added to the activated sludge, the final joint toxicity was similar to the individual effect of 1 mg/L TCS, while 10 mg/L CuNPs contributed to the final stronger toxicity. When TCS was sufficiently reacted with CuNPs in wastewater, their final toxicity to activated sludge was enhanced because the extent of toxicity relief caused by decrease in TCS concentration was less than the degree of deteriorating effect due to the promotion of Cu2+ release from CuNPs.
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Affiliation(s)
- Hong Chen
- a School of Environmental Science and Engineering , Donghua University , Shanghai , People's Republic of China
- b Jiangsu Tongyan Environmental Production Science and Technology Co. Ltd. , Yancheng , People's Republic of China
| | - Yuying Cheng
- a School of Environmental Science and Engineering , Donghua University , Shanghai , People's Republic of China
| | - Di Meng
- a School of Environmental Science and Engineering , Donghua University , Shanghai , People's Republic of China
| | - Gang Xue
- a School of Environmental Science and Engineering , Donghua University , Shanghai , People's Republic of China
| | - Mingji Jiang
- a School of Environmental Science and Engineering , Donghua University , Shanghai , People's Republic of China
| | - Xiang Li
- b Jiangsu Tongyan Environmental Production Science and Technology Co. Ltd. , Yancheng , People's Republic of China
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Tolerance of Trichoderma sp. to Heavy Metals and its Antifungal Activity in Algerian Marine Environment. JOURNAL OF PURE AND APPLIED MICROBIOLOGY 2018. [DOI: 10.22207/jpam.12.2.48] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Kochan K, Peng H, Wood BR, Haritos VS. Single cell assessment of yeast metabolic engineering for enhanced lipid production using Raman and AFM-IR imaging. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:106. [PMID: 29643936 PMCID: PMC5891968 DOI: 10.1186/s13068-018-1108-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 04/04/2018] [Indexed: 05/25/2023]
Abstract
BACKGROUND Biodiesel is a valuable renewable fuel made from derivatized fatty acids produced in plants, animals, and oleaginous microbes. Of the latter, yeasts are of special interest due to their wide use in biotechnology, ability to synthesize fatty acids and store large amounts of triacylglycerols while utilizing non-food carbon sources. While yeast efficiently produce lipids, genetic modification and indeed, lipid pathway metabolic engineering, is usually required for cost-effective production. Traditionally, gas chromatography (GC) is used to measure fatty acid production and to track the success of a metabolic engineering strategy in a microbial culture; here we have employed vibrational spectroscopy approaches at population and single cell level of engineered yeast while simultaneously investigating metabolite levels in subcellular structures. RESULTS Firstly, a strong correlation (r2 > 0.99) was established between Fourier transform infrared (FTIR) lipid in intact cells and GC analysis of fatty acid methyl esters in the differently engineered strains. Confocal Raman spectroscopy of individual cells carrying genetic modifications to enhance fatty acid synthesis and lipid accumulation revealed changes to the lipid body (LB), the storage organelle for lipids in yeast, with their number increasing markedly (up to tenfold higher); LB size was almost double in the strain that also expressed a LB stabilizing gene but considerable variation was also noted between cells. Raman spectroscopy revealed a clear trend toward reduced unsaturated fatty acid content in lipids of cells carrying more complex metabolic engineering. Atomic force microscopy-infrared spectroscopy (AFM-IR) analysis of individual cells indicated large differences in subcellular constituents between strains: cells of the most highly engineered strain had elevated lipid and much reduced carbohydrate in their cytoplasm compared with unmodified cells. CONCLUSIONS Vibrational spectroscopy analysis allowed the simultaneous measurement of strain variability in metabolite production and impact on cellular structures as a result of different gene introductions or knockouts, within a lipid metabolic engineering strategy and these inform the next steps in comprehensive lipid engineering. Additionally, single cell spectroscopic analysis measures heterogeneity in metabolite production across microbial cultures under genetic modification, an emerging issue for efficient biotechnological production.
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Affiliation(s)
- Kamila Kochan
- Centre for Biospectroscopy, School of Chemistry, Monash University, Clayton Campus, Clayton, VIC 3800 Australia
| | - Huadong Peng
- Department of Chemical Engineering, Monash University, Clayton Campus, Clayton, VIC 3800 Australia
| | - Bayden R. Wood
- Centre for Biospectroscopy, School of Chemistry, Monash University, Clayton Campus, Clayton, VIC 3800 Australia
| | - Victoria S. Haritos
- Department of Chemical Engineering, Monash University, Clayton Campus, Clayton, VIC 3800 Australia
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Wang X, Wang X, Hui K, Wei W, Zhang W, Miao A, Xiao L, Yang L. Highly Effective Polyphosphate Synthesis, Phosphate Removal, and Concentration Using Engineered Environmental Bacteria Based on a Simple Solo Medium-Copy Plasmid Strategy. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:214-222. [PMID: 29190088 DOI: 10.1021/acs.est.7b04532] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Microbial polyphosphate (polyP) production is vital to the removal of phosphate from wastewater. However, to date, engineered polyP synthesis using genetically accessible environmental bacteria remains a challenge. This study develops a simple solo medium-copy plasmid-based polyphosphate kinase (PPK1) overexpression strategy for achieving maximum intracellular polyphosphate accumulation by environmental bacteria. The polyP content of the subsequently engineered Citrobacter freundii (CPP) could reach as high as 12.7% of its dry weight. The biomass yield of CPP was also guaranteed because of negligible metabolic burden effects resulting from the medium plasmid copy number. Consequently, substantial removal of phosphate (Pi) from the ambient environment was achieved simultaneously. Because of the need for exogenous Pi for in vivo ATP regeneration, CPP could thoroughly remove Pi from synthetic municipal wastewater when it was applied for the "one-step" removal of Pi with a bench-scale sequence batch membrane reactor. Almost all the phosphorus except for that assimilated by CPP for cellular growth could be recovered in the form of more concentrated Pi. Overall, engineering environmental bacteria to overexpress PPK1 via a solo medium-copy plasmid strategy may represent a valuable general option for not only biotechnological research based on sufficient intracellular polyP production but also removal of Pi from wastewater and Pi enrichment.
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Affiliation(s)
- Xin Wang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Nanjing 210046, P. R. China
| | - Xiaomeng Wang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Nanjing 210046, P. R. China
| | - Kaimin Hui
- Jiangsu Key Laboratory for Biodiversity & Biotechnology and Jiangsu Key Laboratory for Aquatic Crustacean Diseases, College of Life Sciences, Nanjing Normal University , Nanjing 210046, P. R. China
| | - Wei Wei
- Institute of Chemistry and BioMedical Science, State Key Laboratory of Pharmaceutical Biotechnology, School of Life Science, Nanjing University , Nanjing 210046, P. R. China
| | - Wen Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Nanjing 210046, P. R. China
| | - Aijun Miao
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Nanjing 210046, P. R. China
| | - Lin Xiao
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Nanjing 210046, P. R. China
| | - Liuyan Yang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University , Nanjing 210046, P. R. China
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11
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Inherent humic substance promotes microbial denitrification of landfill leachate via shifting bacterial community, improving enzyme activity and up-regulating gene. Sci Rep 2017; 7:12215. [PMID: 28939832 PMCID: PMC5610334 DOI: 10.1038/s41598-017-12565-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 09/11/2017] [Indexed: 11/20/2022] Open
Abstract
Microbial denitrification is the main pathway for nitrogen removal of landfill leachate. Although humic substances (HSs) have been reported in landfill leachate, the effects of HS on denitrification process of activated sludge for leachate treatment are still unknown. In this study, we adopted SAHA as the model HS to study the effects of HS on the denitrification of landfill leachate. After long-term operation at 10 mg/L of Shanghai Aladdin Humic Acid (SAHA), the final nitrate concentration and nitrite accumulation were much lower than the control (5.2 versus 96.2 mg/L; 0.5 versus 34.7 mg/L), and the final N2O emission was 13.1% of the control. The mechanistic study unveiled that SAHA substantially changed the activated sludge community structure and resulted in the dominance of Thauera after long-term exposure to SAHA. Thauera could be able to utilize HSs as electron shuttle to improve denitrificattion performance, especially for nitrite reduction. Moreover, SAHA significantly upregulated the gene expressions and catalytic activities of the key enzymes related to denitrification, the reducing power (NADH) generation, and the electron transport system activity, which accelerated nitrogen oxide reduction. The positive effects of HS on denitrification performance were confirmed by the addition of SAHA into real leachate.
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Weerasekara AW, Jenkins S, Abbott LK, Waite I, McGrath JW, Larma I, Eroglu E, O'Donnell A, Whiteley AS. Microbial phylogenetic and functional responses within acidified wastewater communities exhibiting enhanced phosphate uptake. BIORESOURCE TECHNOLOGY 2016; 220:55-61. [PMID: 27566512 DOI: 10.1016/j.biortech.2016.08.037] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Revised: 08/08/2016] [Accepted: 08/10/2016] [Indexed: 06/06/2023]
Abstract
Acid stimulated accumulation of insoluble phosphorus within microbial cells is highly beneficial to wastewater treatment but remains largely unexplored. Using single cell analyses and next generation sequencing, the response of active polyphosphate accumulating microbial communities under conditions of enhanced phosphorus uptake under both acidic and aerobic conditions was characterised. Phosphorus accumulation activities were highest under acidic conditions (pH 5.5>8.5), where a significant positive effect on bioaccumulation was observed at pH 5.5 when compared to pH 8.5. In contrast to the Betaproteobacteria and Actinobacteria dominated enhanced biological phosphorus removal process, the functionally active polyP accumulators at pH 5.5 belonged to the Gammaproteobacteria, with key accumulators identified as members of the families Aeromonadaceae and Enterobacteriaceae. This study demonstrated a significant enrichment of key polyphosphate kinase and exopolyphosphatase genes within the community metagenome after acidification, concomitant with an increase in P accumulation kinetics.
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Affiliation(s)
- Anjani W Weerasekara
- School of Earth and Environment, Faculty of Science, The University of Western Australia, 35 Stirling Highway, Crawley 6009, Western Australia, Australia; Institute of Agriculture, The University of Western Australia, 35 Stirling Highway, Crawley 6009, Western Australia, Australia
| | - Sasha Jenkins
- School of Earth and Environment, Faculty of Science, The University of Western Australia, 35 Stirling Highway, Crawley 6009, Western Australia, Australia; Institute of Agriculture, The University of Western Australia, 35 Stirling Highway, Crawley 6009, Western Australia, Australia
| | - Lynette K Abbott
- School of Earth and Environment, Faculty of Science, The University of Western Australia, 35 Stirling Highway, Crawley 6009, Western Australia, Australia; Institute of Agriculture, The University of Western Australia, 35 Stirling Highway, Crawley 6009, Western Australia, Australia
| | - Ian Waite
- School of Earth and Environment, Faculty of Science, The University of Western Australia, 35 Stirling Highway, Crawley 6009, Western Australia, Australia; Institute of Agriculture, The University of Western Australia, 35 Stirling Highway, Crawley 6009, Western Australia, Australia
| | - John W McGrath
- School of Biological Sciences and the Institute for Global Food Security, The Queens University of Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, Northern Ireland, United Kingdom
| | - Irma Larma
- Centre for Microscopy, Characterisation and Analysis (CMCA), The University of Western Australia, Crawley, 35 Stirling Highway, 6009 Western Australia, Australia
| | - Ela Eroglu
- Department of Chemical Engineering, Curtin University, Perth 6845, Western Australia, Australia
| | - Anthony O'Donnell
- School of Earth and Environment, Faculty of Science, The University of Western Australia, 35 Stirling Highway, Crawley 6009, Western Australia, Australia; Institute of Agriculture, The University of Western Australia, 35 Stirling Highway, Crawley 6009, Western Australia, Australia
| | - Andrew S Whiteley
- School of Earth and Environment, Faculty of Science, The University of Western Australia, 35 Stirling Highway, Crawley 6009, Western Australia, Australia.
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Schlagenhauf A, Pohl S, Haidl H, Leschnik B, Gallistl S, Muntean W. Non-enzymatic quantification of polyphosphate levels in platelet lysates and releasates. J Pharm Biomed Anal 2016; 131:1-5. [PMID: 27521983 DOI: 10.1016/j.jpba.2016.08.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 08/01/2016] [Accepted: 08/03/2016] [Indexed: 12/28/2022]
Abstract
Inorganic polyphosphate has been shown to be shed upon platelet activation inducing prothrombotic stimuli on the coagulation system. Several methods have been published to detect and quantify polyphosphate in various cells and tissues, but evaluation of platelet content has only been achieved by indirect detection of orthophosphate after enzymatic digestion, thus, relying heavily on specificity of an exopolyphosphatase that is not commercially available. We present a non-enzymatic method for quantification of platelet-derived polyphosphate featuring optimized extraction on silica spin-columns, followed by specific fluorescence detection using DAPI. This allowed us to quantify polyphosphate in platelet lysates, but also in releasates of TRAP-activated platelets for the first time. Extraction of exogenous polyphosphate from buffer and sample matrices resulted in quantitative yields while removing matrix effects observed with direct fluorescence detection. Treatment of eluted fractions with phosphatase completely abrogated polyphosphate-specific fluorescence arguing for no additional compounds influencing the fluorescence detection. This was confirmed by no change in fluorescence intensity in samples previously treated with DNase and RNase. Taken together, we developed a robust and easily standardizable method to quantify polyphosphate in platelet lysates and releasates that will facilitate polyphosphate related investigations of platelet physiology and coagulation.
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Affiliation(s)
- Axel Schlagenhauf
- Department of General Pediatrics and Adolescent Medicine, Medical University of Graz, Austria.
| | - Sina Pohl
- Department of General Pediatrics and Adolescent Medicine, Medical University of Graz, Austria
| | - Harald Haidl
- Department of General Pediatrics and Adolescent Medicine, Medical University of Graz, Austria
| | - Bettina Leschnik
- Department of General Pediatrics and Adolescent Medicine, Medical University of Graz, Austria
| | - Siegfried Gallistl
- Department of General Pediatrics and Adolescent Medicine, Medical University of Graz, Austria
| | - Wolfgang Muntean
- Department of General Pediatrics and Adolescent Medicine, Medical University of Graz, Austria
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14
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Li W, Shan XY, Wang ZY, Lin XY, Li CX, Cai CY, Abbas G, Zhang M, Shen LD, Hu ZQ, Zhao HP, Zheng P. Effect of self-alkalization on nitrite accumulation in a high-rate denitrification system: Performance, microflora and enzymatic activities. WATER RESEARCH 2016; 88:758-765. [PMID: 26595097 DOI: 10.1016/j.watres.2015.11.003] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 10/12/2015] [Accepted: 11/02/2015] [Indexed: 06/05/2023]
Abstract
The self-alkalization of denitrifying automatic circulation (DAC) reactor resulted in a large increase of pH up to 9.20 and caused a tremendous accumulation of nitrite up to 451.1 ± 49.0 mgN L(-1) at nitrate loading rate (NLR) from 35 kgN m(-3) d(-1) to 55 kgN m(-3) d(-1). The nitrite accumulation was greatly relieved even at the same NLR once the pH was maintained at 7.6 ± 0.2 in the system. Enzymatic assays indicated that the long-term bacterial exposure to high pH significantly inhibited the activity of copper type nitrite reductase (NirK) rather than the cytochrome cd1 type nitrite reductase (NirS). The terminal restriction fragment length polymorphism (T-RFLP) analysis revealed that the dominant denitrifying bacteria shifted from the NirS-containing Thauear sp. 27 to the NirK-containing Hyphomicrobium nitrativorans strain NL23 during the self-alkalization. The significant nitrite accumulation in the high-rate denitrification system could be therefore, due to the inhibition of Cu-containing NirK by high pH from the self-alkalization. The results suggest that the NirK-containing H. nitrativorans strain NL23 could be an ideal functional bacterium for the conversion of nitrate to nitrite, i.e. denitritation, which could be combined with anaerobic ammonium oxidation (Anammox) to develop a new process for nitrogen removal from wastewater.
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Affiliation(s)
- Wei Li
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China
| | - Xiao-Yu Shan
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China
| | - Zhi-Yao Wang
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China
| | - Xiao-Yu Lin
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China
| | - Chen-Xu Li
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China
| | - Chao-Yang Cai
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China
| | - Ghulam Abbas
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China
| | - Meng Zhang
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China
| | - Li-Dong Shen
- Department of Agricultural Resource and Environment, College of Applied Meteorology, Nanjing University of Information Science and Technology, Nanjing, China
| | - Zhi-Qiang Hu
- Department of Civil and Environmental Engineering, University of Missouri, Columbia, USA
| | - He-Ping Zhao
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China; MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China.
| | - Ping Zheng
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China.
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15
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Copper-induced adaptation, oxidative stress and its tolerance in Aspergillus niger UCP1261. ELECTRON J BIOTECHN 2015. [DOI: 10.1016/j.ejbt.2015.09.006] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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16
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Kulakovskaya TV, Lichko LP, Ryazanova LP. Diversity of phosphorus reserves in microorganisms. BIOCHEMISTRY (MOSCOW) 2015; 79:1602-14. [PMID: 25749167 DOI: 10.1134/s0006297914130100] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Phosphorus compounds are indispensable components of the Earth's biomass metabolized by all living organisms. Under excess of phosphorus compounds in the environment, microorganisms accumulate reserve phosphorus compounds that are used under phosphorus limitation. These compounds vary in their structure and also perform structural and regulatory functions in microbial cells. The most common phosphorus reserve in microorganism is inorganic polyphosphates, but in some archae and bacteria insoluble magnesium phosphate plays this role. Some yeasts produce phosphomannan as a phosphorus reserve. This review covers also other topics, i.e. accumulation of phosphorus reserves under nutrient limitation, phosphorus reserves in activated sludge, mycorrhiza, and the role of mineral phosphorus compounds in mammals.
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Affiliation(s)
- T V Kulakovskaya
- Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russia.
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17
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Chen H, Li X, Chen Y, Liu Y, Zhang H, Xue G. Performance of wastewater biological phosphorus removal under long-term exposure to CuNPs: adapting toxicity via microbial community structure adjustment. RSC Adv 2015. [DOI: 10.1039/c5ra11579e] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Copper nanoparticles (CuNPs) have been used in a wide range of applications, and the released CuNPs entering wastewater treatment plants (WWTP) might pose potential risks to the wastewater biological treatment process, such as phosphorus removal.
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Affiliation(s)
- Hong Chen
- School of Environmental Science and Engineering
- Donghua University
- Shanghai
- China
| | - Xiang Li
- School of Environmental Science and Engineering
- Donghua University
- Shanghai
- China
| | - Yinguang Chen
- State Key Laboratory of Pollution Control and Resource Reuse
- School of Environmental Science and Engineering
- Tongji University
- Shanghai 200092
- China
| | - Yanan Liu
- School of Environmental Science and Engineering
- Donghua University
- Shanghai
- China
| | - He Zhang
- School of Environmental Science and Engineering
- Donghua University
- Shanghai
- China
| | - Gang Xue
- School of Environmental Science and Engineering
- Donghua University
- Shanghai
- China
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18
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de Lima MAB, Franco LDO, de Souza PM, do Nascimento AE, da Silva CAA, Maia RDCC, Rolim HML, Takaki GMC. Cadmium tolerance and removal from Cunninghamella elegans related to the polyphosphate metabolism. Int J Mol Sci 2013; 14:7180-92. [PMID: 23538844 PMCID: PMC3645682 DOI: 10.3390/ijms14047180] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2013] [Revised: 03/12/2013] [Accepted: 03/18/2013] [Indexed: 11/16/2022] Open
Abstract
The aim of the present work was to study the cadmium effects on growth, ultrastructure and polyphosphate metabolism, as well as to evaluate the metal removal and accumulation by Cunninghamella elegans (IFM 46109) growing in culture medium. The presence of cadmium reduced growth, and a longer lag phase was observed. However, the phosphate uptake from the culture medium increased 15% when compared to the control. Moreover, C. elegans removed 70%-81% of the cadmium added to the culture medium during its growth. The C. elegans mycelia showed a removal efficiency of 280 mg/g at a cadmium concentration of 22.10 mg/L, and the removal velocity of cadmium was 0.107 mg/h. Additionally, it was observed that cadmium induced vacuolization, the presence of electron dense deposits in vacuoles, cytoplasm and cell membranes, as well as the distinct behavior of polyphosphate fractions. The results obtained with C. elegans suggest that precipitation, vacuolization and polyphosphate fractions were associated to cadmium tolerance, and this species demonstrated a higher potential for bioremediation of heavy metals.
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Affiliation(s)
- Marcos A. B. de Lima
- Department of Biology, Federal Rural University of Pernambuco, Recife, PE 52171-900, Brazil; E-Mails: (M.A.B.L.); (L.O.F.)
| | - Luciana de O. Franco
- Department of Biology, Federal Rural University of Pernambuco, Recife, PE 52171-900, Brazil; E-Mails: (M.A.B.L.); (L.O.F.)
| | - Patrícia M. de Souza
- Nucleus of Research in Environmental Sciences, Catholic University of Pernambuco, Recife, PE 52050-590, Brazil; E-Mails: (P.M.S.); (A.E.N.); (C.A.A.S.)
| | - Aline E. do Nascimento
- Nucleus of Research in Environmental Sciences, Catholic University of Pernambuco, Recife, PE 52050-590, Brazil; E-Mails: (P.M.S.); (A.E.N.); (C.A.A.S.)
| | - Carlos A. A. da Silva
- Nucleus of Research in Environmental Sciences, Catholic University of Pernambuco, Recife, PE 52050-590, Brazil; E-Mails: (P.M.S.); (A.E.N.); (C.A.A.S.)
| | - Rita de C. C. Maia
- Department of Veterinary Medicine, Federal Rural University of Pernambuco, Recife, PE 52171-900, Brazil; E-Mail:
| | - Hercília M. L. Rolim
- Postgraduate Program in Pharmaceutical Sciences, Federal University of Piauí, Teresina, PI 64049-550, Brazil; E-Mail:
| | - Galba M. C. Takaki
- Nucleus of Research in Environmental Sciences, Catholic University of Pernambuco, Recife, PE 52050-590, Brazil; E-Mails: (P.M.S.); (A.E.N.); (C.A.A.S.)
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19
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Chen Y, Chen H, Zheng X, Mu H. The impacts of silver nanoparticles and silver ions on wastewater biological phosphorous removal and the mechanisms. JOURNAL OF HAZARDOUS MATERIALS 2012; 239-240:88-94. [PMID: 23021316 DOI: 10.1016/j.jhazmat.2012.07.049] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Revised: 07/24/2012] [Accepted: 07/27/2012] [Indexed: 06/01/2023]
Abstract
The effects of AgNPs and Ag+ (0-5 mg/L) on wastewater enhanced biological phosphorus removal (EBPR) were investigated. The phosphorus removal efficiency was maintained at 99% no matter what the concentrations of AgNPs were, but it was decreased to 48.8% at Ag+ of 1 mg/L, and no net phosphorus was removed at Ag+ greater than 2 mg/L in the batch tests. The uptake of wastewater carbon source and the anaerobic and aerobic transformations of phosphorus, polyhydoxyalkanoates and glycogen were inhibited by Ag+ other than AgNPs. Ag+ showed stronger toxicity on polyphosphate accumulating organisms (PAOs) than glycogen accumulating organisms (GAOs). Further investigation revealed that the decrease in anaerobic phosphorus release by Ag+ was caused by the inhibition on the activities of adenylate kinase and expolyphosphatase, whereas the decrease in aerobic phosphorus uptake was due to the suppression in energy generation for phosphorus uptake. However, the presence of either AgNPs or Ag+ did not lead to cell leakage and membrane damage.
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Affiliation(s)
- Yinguang Chen
- State Key Laboratory of Pollution Control and Resources Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China
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20
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Narancic T, Kenny S, Djokic L, Vasiljevic B, O'Connor K, Nikodinovic-Runic J. Medium-chain-length polyhydroxyalkanoate production by newly isolated Pseudomonas sp. TN301 from a wide range of polyaromatic and monoaromatic hydrocarbons. J Appl Microbiol 2012; 113:508-20. [DOI: 10.1111/j.1365-2672.2012.05353.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Revised: 05/13/2012] [Accepted: 05/24/2012] [Indexed: 11/29/2022]
Affiliation(s)
- T. Narancic
- Institute of Molecular Genetics and Genetic Engineering; University of Belgrade; Belgrade; Serbia
| | - S.T. Kenny
- School of Biomolecular and Biomedical Sciences; Centre for Synthesis and Chemical Biology; University College Dublin; Dublin; Ireland
| | - L. Djokic
- Institute of Molecular Genetics and Genetic Engineering; University of Belgrade; Belgrade; Serbia
| | - B. Vasiljevic
- Institute of Molecular Genetics and Genetic Engineering; University of Belgrade; Belgrade; Serbia
| | - K.E. O'Connor
- School of Biomolecular and Biomedical Sciences; Centre for Synthesis and Chemical Biology; University College Dublin; Dublin; Ireland
| | - J. Nikodinovic-Runic
- Institute of Molecular Genetics and Genetic Engineering; University of Belgrade; Belgrade; Serbia
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21
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Narancic T, Djokic L, Kenny ST, O'Connor KE, Radulovic V, Nikodinovic-Runic J, Vasiljevic B. Metabolic versatility of Gram-positive microbial isolates from contaminated river sediments. JOURNAL OF HAZARDOUS MATERIALS 2012; 215-216:243-251. [PMID: 22421345 DOI: 10.1016/j.jhazmat.2012.02.059] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2011] [Revised: 02/21/2012] [Accepted: 02/22/2012] [Indexed: 05/31/2023]
Abstract
Gram-positive bacteria from river sediments affected by the proximity of a petrochemical industrial site were isolated and characterized with respect to their ability to degrade a wide range of aromatic compounds. In this study we identified metabolically diverse Gram-positive bacteria capable of growth on wide range aromatic compounds in the presence of heavy metals and with the ability to accumulate biopolymers. Thirty-four isolates that were able to use 9 or more common aromatic pollutants, such as benzene, biphenyl, naphthalene etc. as a sole source of carbon and energy included members of Bacillus, Arthrobacter, Rhodococcus, Gordonia, Streptomyces, and Staphylococcus genus. Rhodococcus sp. TN105, Gordonia sp. TN103 and Arthrobacter sp. TN221 were identified as novel strains. Nine isolates were able to grow in the presence of one or more metals (mercury, cadmium, nickel) at high concentration (100mM). Seven isolates could degrade 15 different aromatic compounds and could grow in the presence of one or more heavy metals. Two of these isolates were resistant to multiple antibiotics including erythromycin and nalidixic acid. One third of isolates could accumulate at least one biopolymer. Twelve isolates (mainly Bacillus sp. and Arthrobacter sp.) accumulated polyphosphate, 3 Bacillus sp. accumulated polyhydroxybutyrate, while 4 isolates could accumulate exopolysaccharides.
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Affiliation(s)
- Tanja Narancic
- Institute of Molecular Genetics and Genetic Engineering, University of Belgrade, Vojvode Stepe 444a, P.O. Box 23, 11010 Belgrade, Serbia
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22
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Inorganic polyphosphates in extremophiles and their possible functions. Extremophiles 2012; 16:573-83. [PMID: 22585316 DOI: 10.1007/s00792-012-0457-9] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2012] [Accepted: 04/19/2012] [Indexed: 12/17/2022]
Abstract
Many extremophilic microorganisms are polyextremophiles, being confronted with more than one stress condition. For instance, some thermoacidophilic microorganisms are in addition capable to resist very high metal concentrations. Most likely, they have developed special adaptations to thrive in their living environments. Inorganic polyphosphate (polyP) is a molecule considered to be primitive in its origin and ubiquitous in nature. It has many roles besides being a reservoir for inorganic phosphate and energy. Of special interest are those functions related to survival under stressing conditions in all kinds of cells. PolyP may therefore have a fundamental part in extremophilic microorganism's endurance. Evidence for a role of polyP in the continued existence under acidic conditions, high concentrations of toxic heavy metals and elevated salt concentrations are reviewed in the present work. Actual evidence suggests that polyP may provide mechanistic alternatives in tuning microbial fitness for the adaptation under stressful environmental situations and may be of crucial relevance amongst extremophiles. The enzymes involved in polyP metabolism show structure conservation amongst bacteria and archaea. However, the lack of a canonical polyP synthase in Crenarchaea, which greatly accumulate polyP, strongly suggests that in this phylum a different enzyme may be in charge of its synthesis.
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23
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Breus NA, Ryazanova LP, Suzina NE, Kulakovskaya NV, Valiakhmetov AY, Yashin VA, Sorokin VV, Kulaev IS. Accumulation of inorganic polyphosphates in Saccharomyces cerevisiae under nitrogen deprivation: Stimulation by magnesium ions and peculiarities of localization. Microbiology (Reading) 2011. [DOI: 10.1134/s002626171105002x] [Citation(s) in RCA: 6] [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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24
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Shi T, Fu T, Xie J. Polyphosphate deficiency affects the sliding motility and biofilm formation of Mycobacterium smegmatis. Curr Microbiol 2011; 63:470-6. [PMID: 21882007 DOI: 10.1007/s00284-011-0004-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2011] [Accepted: 08/17/2011] [Indexed: 01/16/2023]
Abstract
Inorganic polyphosphate (polyP) is a ubiquitous linear polymer of hundreds of orthophosphate (Pi) residues linked by ATP-like, high-energy, phosphoanhydride bonds. The gene Rv1026 in Mycobacterium tuberculosis encodes a putative exopolyphosphatase which progressively hydrolyzes the terminal residues of polyP to liberate Pi. Rv1026 was cloned into the expressive plasmid pMV261. The resulting plasmid pRv1026 and the plasmid pMV261 were transformed into M. smegmatis strain mc(2)155 by electroporation. The recombinant M. smegmatis (pRv1026) showed relatively decreased polyP concentration and a phenotype different from the M. smegmatis (pMV261) in sliding motility and biofilm formation. The surfactant Tween 80 can enhance this effect on the sliding motility and biofilm formation of M. smegmatis. There are four different peaks between the gas chromatography of cellular wall fatty acid of the M. smegmatis (pRv1026) and the M. smegmatis (pMV261). These results indicate that polyP deficiency can affect the fatty acid composition of cellular wall and these alteration of cell wall might elucidate the reductive ability of strains to slide and form biofilm. This investigation provides novel recognition about the role of Rv1026, which provides novel clues for further study on the physiological role of Rv1026 in M. tuberculosis.
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Affiliation(s)
- Tingyu Shi
- Institute of Modern Biopharmaceuticals, State Key Laboratory Breeding Base of Eco-Environment and Bio-Resource of the Three Gorges Area, School of Life Sciences, Southwest University, Chongqing 400715, China
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25
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Role of the morphology and polyphosphate in Trichoderma harzianum related to cadmium removal. Molecules 2011; 16:2486-500. [PMID: 21407149 PMCID: PMC6259756 DOI: 10.3390/molecules16032486] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Revised: 03/02/2011] [Accepted: 03/04/2011] [Indexed: 11/23/2022] Open
Abstract
This study concerns the metabolism of polyphosphate in Trichoderma harzianum, a biocontrol agent with innate resistance against most chemicals used in agriculture, including metals, when grown in the presence of different concentrations of cadmium. The biomass production was affected by the concentration of metal used. Control cultures were able to accumulate polyphosphate under the conditions used. Moreover, the presence of cadmium induced a reduction in polyphosphate content related to the concentration used. The morphological/ultrastructural aspects were characterized by using optical and scanning electron microscopy, and were affected by the heavy metal presence and concentration. The efficiency of cadmium removal revealed the potential of the microorganism for use in remediation. The data indicate the potential for polyphosphate accumulation by the fungus, as well as its degradation related to tolerance/survival in the presence of cadmium ions.
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26
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Persson J, Fink P, Goto A, Hood JM, Jonas J, Kato S. To be or not to be what you eat: regulation of stoichiometric homeostasis among autotrophs and heterotrophs. OIKOS 2010. [DOI: 10.1111/j.1600-0706.2009.18545.x] [Citation(s) in RCA: 293] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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27
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Docampo R, Ulrich P, Moreno SNJ. Evolution of acidocalcisomes and their role in polyphosphate storage and osmoregulation in eukaryotic microbes. Philos Trans R Soc Lond B Biol Sci 2010; 365:775-84. [PMID: 20124344 DOI: 10.1098/rstb.2009.0179] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Acidocalcisomes are acidic electron-dense organelles, rich in polyphosphate (poly P) complexed with calcium and other cations. While its matrix contains enzymes related to poly P metabolism, the membrane of the acidocalcisomes has a number of pumps (Ca(2+)-ATPase, V-H(+)-ATPase, H(+)-PPase), exchangers (Na(+)/H(+), Ca(2+)/H(+)), and at least one channel (aquaporin). Acidocalcisomes are present in both prokaryotes and eukaryotes and are an important storage of cations and phosphorus. They also play an important role in osmoregulation and interact with the contractile vacuole complex in a number of eukaryotic microbes. Acidocalcisomes resemble lysosome-related organelles (LRO) from mammalian cells in many of their properties. They share similar morphological characteristics, acidic properties, phosphorus contents and a system for targeting of their membrane proteins through adaptor complex-3 (AP-3). Storage of phosphate and cations may represent the ancestral physiological function of acidocalcisomes, with cation and pH homeostasis and osmoregulatory functions derived following the divergence of prokaryotes and eukaryotes.
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Affiliation(s)
- Roberto Docampo
- Department of Cellular Biology and Center for Tropical and Global Emerging Diseases, University of Georgia, Athens, GA 30602, USA.
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28
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Persson J, Fink P, Goto A, Hood JM, Jonas J, Kato S. To be or not to be what you eat: regulation of stoichiometric homeostasis among autotrophs and heterotrophs. OIKOS 2010. [DOI: 10.1111/j.1600-0706.2010.18545.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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29
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Zhang C, Chen Y, Liu Y. Effect of pH on enzyme activity involved in enhanced biological phosphorus removal system. J Biotechnol 2008. [DOI: 10.1016/j.jbiotec.2008.07.1522] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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30
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Lichko LP, Kulakovskaya TV, Kulaev IS. Inorganic polyphosphates and exopolyphosphatases in different cell compartments of Saccharomyces cerevisiae. BIOCHEMISTRY (MOSCOW) 2007; 71:1171-5. [PMID: 17140377 DOI: 10.1134/s0006297906110010] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The cytosol, nuclei, vacuoles, and mitochondria of the yeast Saccharomyces cerevisiae possess inorganic polyphosphates (polyPs). PolyP levels, spectra of polyP chain lengths, and their dependence on the growth phase are distinguished in the mentioned compartments. Inactivation of the PPX1 gene has no effect on the polyP metabolism under cultivation of the yeast in medium with glucose and 5-7 mM P(i). Inactivation of the PPN1 gene results in elimination of the high-molecular-mass exopolyphosphatases (approximately 120 to 830 kD) of the cytosol, nuclei, vacuoles, and mitochondria of S. cerevisiae suggesting that it is just PPN1 that encodes these enzymes. Expression of the low-molecular-mass exopolyphosphatase of approximately 45 kD encoded by the PPX1 gene decreases under PPN1 inactivation as well. While PPN1 inactivation has negligible effect on polyP levels, it results in increase in the long-chain polyPs in all the compartments under study.
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Affiliation(s)
- L P Lichko
- Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia.
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31
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Tobin KM, McGrath JW, Mullan A, Quinn JP, O'Connor KE. Polyphosphate accumulation by Pseudomonas putida CA-3 and other medium-chain-length polyhydroxyalkanoate-accumulating bacteria under aerobic growth conditions. Appl Environ Microbiol 2006; 73:1383-7. [PMID: 17158616 PMCID: PMC1828677 DOI: 10.1128/aem.02007-06] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Pseudomonas putida CA-3 accumulates polyphosphate (polyP) and medium-chain-length polyhydroxyalkanoate (mclPHA) concurrently under nitrogen limitation. Five other mclPHA-accumulating Pseudomonas strains are capable of simultaneous polyP and mclPHA biosynthesis. It appears that polyP is not the rate-limiting step for mclPHA accumulation in these Pseudomonas strains.
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Affiliation(s)
- Karen M Tobin
- School of Biomolecular and Biomedical Sciences, College of Life Sciences, University College Dublin, Belfield, Dublin 4, Ireland
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32
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Doerner KC, Mason BP. Nutritional deprivation increases intracellular phosphate and polyphosphate in poultry litter microflora. Lett Appl Microbiol 2006; 42:527-31. [PMID: 16620214 DOI: 10.1111/j.1472-765x.2006.01883.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
AIMS To determine if mixed microflora from poultry litter accumulates phosphate when deprived of carbon and energy or nitrogen sources. METHODS AND RESULTS Microbial enrichments from poultry litter capable of metabolizing ammonia, amino acids, and glucose were subjected to nutritional deprivation and the effects on intracellular phosphate levels were determined. Results indicate deprivation of glucose yields a 38 and 50% increase in intracellular phosphate and polyphosphate levels, respectively. Deprivation of nitrogen sources did not result in significant intracellular phosphate accumulation. CONCLUSIONS Micro-organisms normally present in poultry litter respond to carbohydrate deprivation by accumulating intracellular phosphate. SIGNIFICANCE AND IMPACT OF THE STUDY Poultry litter typically contains significant levels of phosphate which contribute to environmental pollution when applied to land. Phosphate is highly mobile in soils and often drains into local watersheds following rain events. This study raises the possibility that poultry litter micro-organisms may have the capacity to sequester phosphate, which could delay or diminish phosphate run-off.
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Affiliation(s)
- K C Doerner
- Department of Biology, Western Kentucky University, KY 42101-1080, USA.
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33
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Moriarty TF, Mullan A, McGrath JW, Quinn JP, Elborn JS, Tunney MM. Effect of reduced pH on inorganic polyphosphate accumulation by Burkholderia cepacia complex isolates. Lett Appl Microbiol 2006; 42:617-23. [PMID: 16706902 DOI: 10.1111/j.1472-765x.2006.01930.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIMS Burkholderia cepacia complex (Bcc) isolates causing pulmonary infection in cystic fibrosis (CF) patients grow within an acidic environment in the lung. As exposure to acid pH has been shown to increase intracellular inorganic polyphosphate (polyP) formation in some bacteria, we investigated the inter-relationship between acidic pH and polyP accumulation in Bcc isolates. METHODS AND RESULTS The formation of polyP by one Burkholderia cenocepacia clinical isolate was initially examined at a range of pH values by measuring total intracellular polyP accumulation and phosphate uptake. The pattern of polyP accumulation corresponded with the pattern of phosphate uptake with the maximum for both occurring at pH 5.5. Phosphate uptake and formation of polyP by this isolate was further determined over 48 h at pH 5.5, 6.5 and 7.5; formation of polyP was maximal at pH 5.5 at all time points studied. Sixteen of 17 additional clinical and environmental Bcc isolates examined also exhibited maximum phosphate uptake at pH 5.5. CONCLUSIONS Both clinical and environmental Bcc isolates, of five genomovars, show enhanced formation of polyP in an acidic environment. Given both the speculated role of polyP in pathogenesis, cell signalling and biofilm formation and the acidic nature of the CF lung, this may be of considerable clinical importance. SIGNIFICANCE AND IMPACT OF THE STUDY Growth of Bcc in an acidic environment, such as that found in the lungs of CF patients may be influenced in part by polyP accumulation.
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Affiliation(s)
- T F Moriarty
- Clinical and Practice Research Group, School of Pharmacy, Queen's University Belfast, Belfast, Northern Ireland
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Larraya LM, Boyce KJ, So A, Steen BR, Jones S, Marra M, Kronstad JW. Serial analysis of gene expression reveals conserved links between protein kinase A, ribosome biogenesis, and phosphate metabolism in Ustilago maydis. EUKARYOTIC CELL 2006; 4:2029-43. [PMID: 16339721 PMCID: PMC1317500 DOI: 10.1128/ec.4.12.2029-2043.2005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The switch from budding to filamentous growth is a key aspect of invasive growth and virulence for the fungal phytopathogen Ustilago maydis. The cyclic AMP (cAMP) signaling pathway regulates dimorphism in U. maydis, as demonstrated by the phenotypes of mutants with defects in protein kinase A (PKA). Specifically, a mutant lacking the regulatory subunit of PKA encoded by the ubc1 gene displays a multiple-budded phenotype and fails to incite disease symptoms, although proliferation does occur in the plant host. A mutant with a defect in a catalytic subunit of PKA, encoded by adr1, has a constitutively filamentous phenotype and is nonpathogenic. We employed serial analysis of gene expression to examine the transcriptomes of a wild-type strain and the ubc1 and adr1 mutants to further define the role of PKA in U. maydis. The mutants displayed changes in the transcript levels for genes encoding ribosomal proteins, genes regulated by the b mating-type proteins, and genes for metabolic functions. Importantly, the ubc1 mutant displayed elevated transcript levels for genes involved in phosphate acquisition and storage, thus revealing a connection between cAMP and phosphate metabolism. Further experimentation indicated a phosphate storage defect and elevated acid phosphatase activity for the ubc1 mutant. Elevated phosphate levels in culture media also enhanced the filamentous growth of wild-type cells in response to lipids, a finding consistent with PKA regulation of morphogenesis in U. maydis. Overall, these findings extend our understanding of cAMP signaling in U. maydis and reveal a link between phosphate metabolism and morphogenesis.
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Affiliation(s)
- Luis M Larraya
- Michael Smith Laboratories, 2185 East Mall, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
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Mullan A, McGrath JW, Adamson T, Irwin S, Quinn JP. Pilot-scale evaluation of the application of low pH-inducible polyphosphate accumulation to the biological removal of phosphate from wastewaters. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2006; 40:296-301. [PMID: 16433364 DOI: 10.1021/es0509782] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
To investigate the possible biotechnological application of the phenomenon of low pH-inducible phosphate uptake and polyphosphate accumulation, previously reported using pure microbial cultures and under laboratory conditions, a 2000 L activated sludge pilot plant was constructed at a municipal sewage treatment works. When operated as a single-stage reactor this removed more than 60% of influent phosphate from primary settled sewage at a pH of 6.0, as opposed to approximately 30% at the typical operational pH for the works of 7.0-7.3-yet without any deleterious effect on other treatment parameters. At these pH values the phosphorus content of the sludge was, respectively, 4.2% and 2.0%. At pH 6.0 some 33.9% of sludge microbial cells were observed to contain polyphosphate inclusions; the corresponding value at pH 7.0 was 18.7%. Such a process may serve as a prototype for the development of alternative biological and chemical options for phosphate removal from wastewaters.
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Affiliation(s)
- Alan Mullan
- School of Biology and Biochemistry and QUESTOR Centre, The Queen's University of Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast, BT9 7BL, Northern Ireland
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36
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Specific Features of Metabolism and Functions of High-Molecular Inorganic Polyphosphates in Yeasts as Representatives of Lower Eukaryotes. Mol Biol 2005. [DOI: 10.1007/s11008-005-0065-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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37
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McGrath JW, Kulakova AN, Kulakov LA, Quinn JP. In vitro detection and characterisation of a polyphosphate synthesising activity in the yeast Candida humicola G-1. Res Microbiol 2005; 156:485-91. [PMID: 15862446 DOI: 10.1016/j.resmic.2004.12.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2004] [Revised: 12/22/2004] [Accepted: 12/23/2004] [Indexed: 11/23/2022]
Abstract
An in vitro detectable polyphosphate-synthesising activity was characterised using two independent assay systems in extracts of the yeast Candida humicola G-1. Its properties were similar to those of a range of bacterial polyphosphate kinase enzymes. PCR amplification of C. humicola genomic DNA using universal primers for bacterial polyphosphate kinase genes yielded a product whose translated sequence showed up to 34% amino acid similarity to the bacterial enzyme.
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Affiliation(s)
- John W McGrath
- School of Biology and Biochemistry and QUESTOR Centre, The Queen's University of Belfast, Medical Biology Centre, 97 Lisburn Rd., Belfast, BT9 7BL, Northern Ireland.
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38
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Chávez FP, Lünsdorf H, Jerez CA. Growth of polychlorinated-biphenyl-degrading bacteria in the presence of biphenyl and chlorobiphenyls generates oxidative stress and massive accumulation of inorganic polyphosphate. Appl Environ Microbiol 2004; 70:3064-72. [PMID: 15128568 PMCID: PMC404396 DOI: 10.1128/aem.70.5.3064-3072.2004] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Inorganic polyphosphate (polyP) plays a significant role in increasing bacterial cell resistance to unfavorable environmental conditions and in regulating different biochemical processes. Using transmission electron microscopy of the polychlorinated biphenyl (PCB)-degrading bacterium Pseudomonas sp. strain B4 grown in defined medium with biphenyl as the sole carbon source, we observed large and abundant electron-dense granules at all stages of growth and following a shift from glucose to biphenyl or chlorobiphenyls. Using energy dispersive X-ray analysis and electron energy loss spectroscopy with an integrated energy-filtered transmission electron microscope, we demonstrated that these granules were mainly composed of phosphate. Using sensitive enzymatic methods to quantify cellular polyP, we confirmed that this polymer accumulates in PCB-degrading bacteria when they grow in the presence of biphenyl and chlorobiphenyls. Concomitant increases in the levels of the general stress protein GroEl and reactive oxygen species were also observed in chlorobiphenyl-grown cells, indicating that these bacteria adjust their physiology with a stress response when they are confronted with compounds that serve as carbon and energy sources and at the same time are chemical stressors.
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Affiliation(s)
- Francisco P Chávez
- Department of Biology, Faculty of Sciences, University of Chile, Santiago, Chile
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McGrath JW, Quinn JP. Microbial phosphate removal and polyphosphate production from wastewaters. ADVANCES IN APPLIED MICROBIOLOGY 2003; 52:75-100. [PMID: 12964240 DOI: 10.1016/s0065-2164(03)01003-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- John W McGrath
- School of Biology and Biochemistry, QUESTOR Center, Queen's University of Belfast, Medical Biology Centre Belfast, BT9 7BL Northern Ireland
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Ayraud S, Janvier B, Salaun L, Fauchère JL. Modification in the ppk gene of Helicobacter pylori during single and multiple experimental murine infections. Infect Immun 2003; 71:1733-9. [PMID: 12654786 PMCID: PMC152028 DOI: 10.1128/iai.71.4.1733-1739.2003] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The bacterial pathogen Helicobacter pylori is highly adapted to the human stomach, and a high level of polymorphism is observed among clinical isolates. This polymorphism may be the consequence of adaptive changes during colonization, making a strain better able to survive, to evade the immune system, and to provoke a chronic infection. To investigate the mechanisms involved in the acquisition of diversity in H. pylori, mouse models of single infections, coinfections, and superinfections were developed. These experimental infections were conducted with strain SS1, well known to be mouse adapted, and with two strains freshly isolated from infected patients: Hp141 and Hp145. Genetic modifications occurring in these strains were studied over time by comparing randomly selected colonies of the emerging strains to those of the infecting strains by using randomly amplified polymorphic DNA fingerprinting with six different primers and by using PCR to amplify the vacA and cagA genes. We showed that, regardless of the number of infecting strains, only one emerged from the animals and that the establishment of a first strain thwarted the implantation of a second strain. During both a single infection and a coinfection with SS1, Hp141 was replaced by a genetic variant (Hp141v) that overcame SS1 in coinfection experiments. Hp141v exhibited a deletion of a 102-bp repeated sequence within the ppk gene, which encodes polyphosphate kinase (PPK), an enzyme involved in the physiological adaptation of the microbial cell to nutritional and environmental stresses. The deletion led to higher enzymatic activity of PPK, and the variant exhibited a better capacity to colonize mice. Considering that the modified gene is known to be involved in adaptation to a new environment, our results are consistent with an adaptive change in strain Hp141 and suggest that PPK is an important virulence factor in H. pylori.
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Affiliation(s)
- Sarah Ayraud
- Laboratoire de Microbiologie A, CHU La Milétrie, BP577, Université de Poitiers, 86021 Poitiers cedex, France.
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Mullan A, Quinn JP, McGrath JW. A nonradioactive method for the assay of polyphosphate kinase activity and its application in the study of polyphosphate metabolism in Burkholderia cepacia. Anal Biochem 2002; 308:294-9. [PMID: 12419342 DOI: 10.1016/s0003-2697(02)00249-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Studies of polyphosphate (polyP) metabolism in microorganisms have been hampered by the lack of a convenient method for the assay in cell extracts of the activity of polyphosphate kinase (PPK), the enzyme principally responsible for microbial polyP biosynthesis. We report the development of such an assay, based on the well-established metachromatic reaction, with toluidine blue, of the polyP formed during the PPK-catalyzed reaction. The method was successfully used in the characterization of PPK activity in crude extracts of an environmental Burkholderia cepacia isolate. The development of a protocol for the physical recovery of polyP from solution is also reported.
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Affiliation(s)
- Alan Mullan
- School of Biology and Biochemistry and QUESTOR Centre, The Queen's University of Belfast, Medical Biology Centre, Ireland
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Peñalva MA, Arst HN. Regulation of gene expression by ambient pH in filamentous fungi and yeasts. Microbiol Mol Biol Rev 2002; 66:426-46, table of contents. [PMID: 12208998 PMCID: PMC120796 DOI: 10.1128/mmbr.66.3.426-446.2002] [Citation(s) in RCA: 207] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Life, as we know it, is water based. Exposure to hydroxonium and hydroxide ions is constant and ubiquitous, and the evolutionary pressure to respond appropriately to these ions is likely to be intense. Fungi respond to their environments by tailoring their output of activities destined for the cell surface or beyond to the ambient pH. We are beginning to glimpse how they sense ambient pH and transmit this information to the transcription factor, whose roles ensure that a suitable collection of gene products will be made. Although relatively little is known about pH signal transduction itself, its consequences for the cognate transcription factor are much clearer. Intriguingly, homologues of components of this system mediating the regulation of fungal gene expression by ambient pH are to be found in the animal kingdom. The potential applied importance of this regulatory system lies in its key role in fungal pathogenicity of animals and plants and in its control of fungal production of toxins, antibiotics, and secreted enzymes.
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Chen W, Palmer RJ, Kuramitsu HK. Role of polyphosphate kinase in biofilm formation by Porphyromonas gingivalis. Infect Immun 2002; 70:4708-15. [PMID: 12117989 PMCID: PMC128176 DOI: 10.1128/iai.70.8.4708-4715.2002] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In order to assess the role of polyphosphate kinase (PPK) in the physiology of Porphyromonas gingivalis, a ppk gene mutant, CW120, was constructed and characterized. P. gingivalis was demonstrated to synthesize short-chain polyphosphate (polyP) but not long-chain polyP. CW120 failed to survive in the stationary phase as well as the parental cell did, and it was attenuated in biofilm formation on polyvinylchloride and glass surfaces. Furthermore, the complementation by insertion of an intact copy of the ppk gene into the mutant CW120 restored its biofilm formation and stationary-phase survival. These results suggest that PPK may be important for incorporation of these organisms into subgingival plaque in the human oral cavity.
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Affiliation(s)
- Wen Chen
- Department of Oral Biology, State University of New York, Buffalo 14214, USA
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Mullan A, Quinn JP, McGrath JW. Enhanced phosphate uptake and polyphosphate accumulation in Burkholderia cepacia grown under low pH conditions. MICROBIAL ECOLOGY 2002; 44:69-77. [PMID: 12187377 DOI: 10.1007/s00248-002-3004-x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2001] [Accepted: 12/04/2001] [Indexed: 05/23/2023]
Abstract
Of bacterial cells in a sample of activated sludge, 34% contained detectable intracellular polyphosphate inclusions following Neisser staining, when grown on glucose/mineral salts medium at pH 5.5; at pH 7.5 only 7% of cells visibly accumulated polyphosphate. In a sludge isolate of Burkholderia cepacia chosen for further study, maximal removal of phosphate and accumulation of polyphosphate occurred at pH 5.5; levels were up to 220% and 330% higher, respectively, than in cells grown at pH 7.5. During the early stationary phase of growth at pH 5.5 a maximum level of intracellular polyphosphate that comprised 13.6% of cellular dry weight was reached. Polyphosphate kinase activity was detected in actively growing cells only when cultured at pH 5.5. The phenomenon of acid-stimulated phosphate uptake and polyphosphate accumulation in this environmental bacterial population parallels observations previously made by us in the yeast Candida humicola and may thus represent a widespread microbial response to low external pH values.
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Affiliation(s)
- A Mullan
- School of Biology and Biochemistry and QUESTOR Centre, The Queen's University of Belfast, Northern Ireland
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45
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McGrath JW, Cleary S, Mulla A, Quinn JP. Acid-stimulated phosphate uptake by activated sludge microorganisms under aerobic laboratory conditions. WATER RESEARCH 2001; 35:4317-4322. [PMID: 11763033 DOI: 10.1016/s0043-1354(01)00164-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Activated sludge inocula taken from five different wastewater treatment plants were grown aerobically under laboratory conditions on mineral salts medium containing either glucose or skimmed milk powder as carbon source. Cultures showed increases of between 50% and 143% in levels of phosphate uptake from the medium when the growth pH was 5.5 rather than 7.5. Of 100 individual sludge microbial isolates studied, 34 demonstrated such acid-stimulated luxury phosphate uptake; the optimum pH for the process was shown to lie between 5.0 and 6.5. Enhanced phosphate removal by these isolates was accompanied by increases of between 2 and 10.5-fold in their polyphosphate content; this was visualised as intracellular inclusions. Acid-stimulated luxury phosphate uptake by environmental microorganisms is a previously-unrecognised phenomenon that may have application in novel technologies for nutrient removal from wastewaters.
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Affiliation(s)
- J W McGrath
- School of Biology and Biochemistry, The Queen's University of Belfast, Medical Biology Centre, Northern Ireland, UK.
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