1
|
Goff JL, Szink EG, Durrence KL, Lui LM, Nielsen TN, Kuehl JV, Hunt KA, Chandonia JM, Huang J, Thorgersen MP, Poole FL, Stahl DA, Chakraborty R, Deutschbauer AM, Arkin AP, Adams MWW. Genomic and environmental controls on Castellaniella biogeography in an anthropogenically disturbed subsurface. ENVIRONMENTAL MICROBIOME 2024; 19:26. [PMID: 38671539 PMCID: PMC11046850 DOI: 10.1186/s40793-024-00570-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2024] [Accepted: 04/19/2024] [Indexed: 04/28/2024]
Abstract
Castellaniella species have been isolated from a variety of mixed-waste environments including the nitrate and multiple metal-contaminated subsurface at the Oak Ridge Reservation (ORR). Previous studies examining microbial community composition and nitrate removal at ORR during biostimulation efforts reported increased abundances of members of the Castellaniella genus concurrent with increased denitrification rates. Thus, we asked how genomic and abiotic factors control the Castellaniella biogeography at the site to understand how these factors may influence nitrate transformation in an anthropogenically impacted setting. We report the isolation and characterization of several Castellaniella strains from the ORR subsurface. Five of these isolates match at 100% identity (at the 16S rRNA gene V4 region) to two Castellaniella amplicon sequence variants (ASVs), ASV1 and ASV2, that have persisted in the ORR subsurface for at least 2 decades. However, ASV2 has consistently higher relative abundance in samples taken from the site and was also the dominant blooming denitrifier population during a prior biostimulation effort. We found that the ASV2 representative strain has greater resistance to mixed metal stress than the ASV1 representative strains. We attribute this resistance, in part, to the large number of unique heavy metal resistance genes identified on a genomic island in the ASV2 representative genome. Additionally, we suggest that the relatively lower fitness of ASV1 may be connected to the loss of the nitrous oxide reductase (nos) operon (and associated nitrous oxide reductase activity) due to the insertion at this genomic locus of a mobile genetic element carrying copper resistance genes. This study demonstrates the value of integrating genomic, environmental, and phenotypic data to characterize the biogeography of key microorganisms in contaminated sites.
Collapse
Affiliation(s)
- Jennifer L Goff
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, 30602, USA
- State University of New York College of Environmental Science and Forestry, Syracuse, NY, USA
| | - Elizabeth G Szink
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, 30602, USA
| | - Konnor L Durrence
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, 30602, USA
| | - Lauren M Lui
- Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Torben N Nielsen
- Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Jennifer V Kuehl
- Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Kristopher A Hunt
- Department of Civil and Environmental Engineering, University of Washington, Seattle, WA, USA
| | - John-Marc Chandonia
- Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Jiawen Huang
- Earth and Environmental Science Area, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Michael P Thorgersen
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, 30602, USA
| | - Farris L Poole
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, 30602, USA
| | - David A Stahl
- Department of Civil and Environmental Engineering, University of Washington, Seattle, WA, USA
| | - Romy Chakraborty
- Earth and Environmental Science Area, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Adam M Deutschbauer
- Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Adam P Arkin
- Environmental Genomics and Systems Biology, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Bioengineering, University of California-Berkeley, Berkeley, CA, USA
| | - Michael W W Adams
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, 30602, USA.
| |
Collapse
|
2
|
Zhang L, Zhao H, Qin S, Hu C, Shen Y, Qu B, Bai Y, Liu B. Genome-Resolved Metagenomics and Denitrifying Strain Isolation Reveal New Insights into Microbial Denitrification in the Deep Vadose Zone. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:2323-2334. [PMID: 38267389 DOI: 10.1021/acs.est.3c06466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2024]
Abstract
The heavy use of nitrogen fertilizer in intensive agricultural areas often leads to nitrate accumulation in subsurface soil and nitrate contamination in groundwater, which poses a serious risk to public health. Denitrifying microorganisms in the subsoil convert nitrate to gaseous forms of nitrogen, thereby mitigating the leaching of nitrate into groundwater. Here, we investigated denitrifying microorganisms in the deep vadose zone of a typical intensive agricultural area in China through microcosm enrichment, genome-resolved metagenomic analysis, and denitrifying bacteria isolation. A total of 1000 metagenome-assembled genomes (MAGs) were reconstructed, resulting in 98 high-quality, dereplicated MAGs that contained denitrification genes. Among them, 32 MAGs could not be taxonomically classified at the genus or species level, indicating that a broader spectrum of taxonomic groups is involved in subsoil denitrification than previously recognized. A denitrifier isolate library was constructed by using a strategy combining high-throughput and conventional cultivation techniques. Assessment of the denitrification characteristics of both the MAGs and isolates demonstrated the dominance of truncated denitrification. Functional screening revealed the highest denitrification activity in two complete denitrifiers belonging to the genus Pseudomonas. These findings greatly expand the current knowledge of the composition and function of denitrifying microorganisms in subsoils. The constructed isolate library provided the first pool of subsoil-denitrifying microorganisms that could facilitate the development of microbe-based technologies for nitrate attenuation in groundwater.
Collapse
Affiliation(s)
- Linqi Zhang
- Key Laboratory of Agricultural Water Resources, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang 050021, China
| | - Huicheng Zhao
- Key Laboratory of Agricultural Water Resources, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang 050021, China
| | - Shuping Qin
- Key Laboratory of Agricultural Water Resources, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang 050021, China
| | - Chunsheng Hu
- Key Laboratory of Agricultural Water Resources, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang 050021, China
| | - Yanjun Shen
- Key Laboratory of Agricultural Water Resources, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang 050021, China
| | - Baoyuan Qu
- State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
- CAS-JIC Centre of Excellence for Plant and Microbial Sciences, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Yang Bai
- State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
- CAS-JIC Centre of Excellence for Plant and Microbial Sciences, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Binbin Liu
- Key Laboratory of Agricultural Water Resources, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang 050021, China
- Xiong'an Institute of Innovation, Chinese Academy of Sciences, Xiong'an 071700, China
| |
Collapse
|
3
|
Takahashi K, Oshiki M, Ruan C, Morinaga K, Toyofuku M, Nomura N, Johnson DR. Denitrification in low oxic environments increases the accumulation of nitrogen oxide intermediates and modulates the evolutionary potential of microbial populations. ENVIRONMENTAL MICROBIOLOGY REPORTS 2024; 16:e13221. [PMID: 38037543 PMCID: PMC10866065 DOI: 10.1111/1758-2229.13221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 11/15/2023] [Indexed: 12/02/2023]
Abstract
Denitrification in oxic environments occurs when a microorganism uses nitrogen oxides as terminal electron acceptors even though oxygen is available. While this phenomenon is well-established, its consequences on ecological and evolutionary processes remain poorly understood. We hypothesize here that denitrification in oxic environments can modify the accumulation profiles of nitrogen oxide intermediates with cascading effects on the evolutionary potentials of denitrifying microorganisms. To test this, we performed laboratory experiments with Paracoccus denitrificans and complemented them with individual-based computational modelling. We found that denitrification in low oxic environments significantly increases the accumulation of nitrite and nitric oxide. We further found that the increased accumulation of these intermediates has a negative effect on growth at low pH. Finally, we found that the increased negative effect at low pH increases the number of individuals that contribute to surface-associated growth. This increases the amount of genetic diversity that is preserved from the initial population, thus increasing the number of genetic targets for natural selection to act upon and resulting in higher evolutionary potentials. Together, our data highlight that denitrification in low oxic environments can affect the ecological processes and evolutionary potentials of denitrifying microorganisms by modifying the accumulation of nitrogen oxide intermediates.
Collapse
Affiliation(s)
- Kohei Takahashi
- Graduate School of Sciences and TechnologiesUniversity of TsukubaTsukubaIbarakiJapan
- Department of Environmental MicrobiologySwiss Federal Institute of Aquatic Science and Technology (Eawag)DübendorfSwitzerland
| | - Mamoru Oshiki
- Division of Environmental Engineering, Faculty of EngineeringHokkaido UniversitySapporoHokkaidoJapan
| | - Chujin Ruan
- Department of Environmental MicrobiologySwiss Federal Institute of Aquatic Science and Technology (Eawag)DübendorfSwitzerland
| | - Kana Morinaga
- Graduate School of Sciences and TechnologiesUniversity of TsukubaTsukubaIbarakiJapan
| | - Masanori Toyofuku
- Faculty of Life and Environmental SciencesUniversity of TsukubaTsukubaIbarakiJapan
- Microbiology Research Center for SustainabilityUniversity of TsukubaTsukubaIbarakiJapan
| | - Nobuhiko Nomura
- Faculty of Life and Environmental SciencesUniversity of TsukubaTsukubaIbarakiJapan
- Microbiology Research Center for SustainabilityUniversity of TsukubaTsukubaIbarakiJapan
| | - David R. Johnson
- Department of Environmental MicrobiologySwiss Federal Institute of Aquatic Science and Technology (Eawag)DübendorfSwitzerland
- Institute of Ecology and EvolutionUniversity of BernBernSwitzerland
| |
Collapse
|
4
|
Kosgey K, Zungu PV, Bux F, Kumari S. Biological nitrogen removal from low carbon wastewater. Front Microbiol 2022; 13:968812. [PMID: 36466689 PMCID: PMC9709150 DOI: 10.3389/fmicb.2022.968812] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 10/28/2022] [Indexed: 08/13/2023] Open
Abstract
Nitrogen has traditionally been removed from wastewater by nitrification and denitrification processes, in which organic carbon has been used as an electron donor during denitrification. However, some wastewaters contain low concentrations of organic carbon, which may require external organic carbon supply, increasing treatment costs. As a result, processes such as partial nitrification/anammox (anaerobic ammonium oxidation) (PN/A), autotrophic denitrification, nitritation-denitritation and bioelectrochemical processes have been studied as possible alternatives, and are thus evaluated in this study based on process kinetics, applicability at large-scale and process configuration. Oxygen demand for nitritation-denitritation and PN/A is 25% and 60% lower than for nitrification/denitrification, respectively. In addition, PN/A process does not require organic carbon supply, while its supply for nitritation-denitritation is 40% less than for nitrification/denitrification. Both PN/A and nitritation-denitritation produce less sludge compared to nitrification/denitrification, which saves on sludge handling costs. Similarly, autotrophic denitrification generates less sludge compared to heterotrophic denitrification and could save on sludge handling costs. However, autotrophic denitrification driven by metallic ions, elemental sulfur (S) and its compounds could generate harmful chemicals. On the other hand, hydrogenotrophic denitrification can remove nitrogen completely without generation of harmful chemicals, but requires specialized equipment for generation and handling of hydrogen gas (H2), which complicates process configuration. Bioelectrochemical processes are limited by low kinetics and complicated process configuration. In sum, anammox-mediated processes represent the best alternative to nitrification/denitrification for nitrogen removal in low- and high-strength wastewaters.
Collapse
Affiliation(s)
- Kiprotich Kosgey
- Institute for Water and Wastewater Technology, Durban University of Technology, Durban, South Africa
| | | | | | - Sheena Kumari
- Institute for Water and Wastewater Technology, Durban University of Technology, Durban, South Africa
| |
Collapse
|
5
|
Theillet FX, Luchinat E. In-cell NMR: Why and how? PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2022; 132-133:1-112. [PMID: 36496255 DOI: 10.1016/j.pnmrs.2022.04.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 04/19/2022] [Accepted: 04/27/2022] [Indexed: 06/17/2023]
Abstract
NMR spectroscopy has been applied to cells and tissues analysis since its beginnings, as early as 1950. We have attempted to gather here in a didactic fashion the broad diversity of data and ideas that emerged from NMR investigations on living cells. Covering a large proportion of the periodic table, NMR spectroscopy permits scrutiny of a great variety of atomic nuclei in all living organisms non-invasively. It has thus provided quantitative information on cellular atoms and their chemical environment, dynamics, or interactions. We will show that NMR studies have generated valuable knowledge on a vast array of cellular molecules and events, from water, salts, metabolites, cell walls, proteins, nucleic acids, drugs and drug targets, to pH, redox equilibria and chemical reactions. The characterization of such a multitude of objects at the atomic scale has thus shaped our mental representation of cellular life at multiple levels, together with major techniques like mass-spectrometry or microscopies. NMR studies on cells has accompanied the developments of MRI and metabolomics, and various subfields have flourished, coined with appealing names: fluxomics, foodomics, MRI and MRS (i.e. imaging and localized spectroscopy of living tissues, respectively), whole-cell NMR, on-cell ligand-based NMR, systems NMR, cellular structural biology, in-cell NMR… All these have not grown separately, but rather by reinforcing each other like a braided trunk. Hence, we try here to provide an analytical account of a large ensemble of intricately linked approaches, whose integration has been and will be key to their success. We present extensive overviews, firstly on the various types of information provided by NMR in a cellular environment (the "why", oriented towards a broad readership), and secondly on the employed NMR techniques and setups (the "how", where we discuss the past, current and future methods). Each subsection is constructed as a historical anthology, showing how the intrinsic properties of NMR spectroscopy and its developments structured the accessible knowledge on cellular phenomena. Using this systematic approach, we sought i) to make this review accessible to the broadest audience and ii) to highlight some early techniques that may find renewed interest. Finally, we present a brief discussion on what may be potential and desirable developments in the context of integrative studies in biology.
Collapse
Affiliation(s)
- Francois-Xavier Theillet
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France.
| | - Enrico Luchinat
- Dipartimento di Scienze e Tecnologie Agro-Alimentari, Alma Mater Studiorum - Università di Bologna, Piazza Goidanich 60, 47521 Cesena, Italy; CERM - Magnetic Resonance Center, and Neurofarba Department, Università degli Studi di Firenze, 50019 Sesto Fiorentino, Italy
| |
Collapse
|
6
|
Jiang C, Wang X, Wang H, Xu S, Zhang W, Meng Q, Zhuang X. Achieving Partial Nitritation by Treating Sludge With Free Nitrous Acid: The Potential Role of Quorum Sensing. Front Microbiol 2022; 13:897566. [PMID: 35572707 PMCID: PMC9095614 DOI: 10.3389/fmicb.2022.897566] [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: 03/16/2022] [Accepted: 04/08/2022] [Indexed: 11/13/2022] Open
Abstract
Partial nitritation is increasingly regarded as a promising biological nitrogen removal process owing to lower energy consumption and better nitrogen removal performance compared to the traditional nitrification process, especially for the treatment of low carbon wastewater. Regulating microbial community structure and function in sewage treatment systems, which are mainly determined by quorum sensing (QS), by free nitrous acid (FNA) to establish a partial nitritation process is an efficient and stable method. Plenty of research papers reported that QS systems ubiquitously existed in ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB), and various novel nitrogen removal processes based on partial nitritation were successfully established using FNA. Although the probability that partial nitritation process might be achieved by the regulation of FNA on microbial community structure and function through the QS system was widely recognized and discussed, the potential role of QS in partial nitritation achievement by FNA and the regulation mechanism of FNA on QS system have not been reviewed. This article systematically reviewed the potential role of QS in the establishment of partial nitritation using FNA to regulate activated sludge flora based on the summary and analysis of the published literature for the first time, and future research directions were also proposed.
Collapse
Affiliation(s)
- Cancan Jiang
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China.,College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Xu Wang
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China.,College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Huacai Wang
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China.,The Institute of International Rivers and Eco-Security, Yunnan University, Kunming, China
| | - Shengjun Xu
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China.,College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
| | - Wei Zhang
- Shenzhen Shenshui Water Resources Consulting Co., Ltd., Shenzhen, China
| | - Qingjie Meng
- Shenzhen Shenshui Water Resources Consulting Co., Ltd., Shenzhen, China
| | - Xuliang Zhuang
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China.,College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China.,Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China
| |
Collapse
|
7
|
Borer B, Ciccarese D, Johnson D, Or D. Spatial organization in microbial range expansion emerges from trophic dependencies and successful lineages. Commun Biol 2020; 3:685. [PMID: 33208809 PMCID: PMC7674409 DOI: 10.1038/s42003-020-01409-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 10/09/2020] [Indexed: 12/15/2022] Open
Abstract
Evidence suggests that bacterial community spatial organization affects their ecological function, yet details of the mechanisms that promote spatial patterns remain difficult to resolve experimentally. In contrast to bacterial communities in liquid cultures, surface-attached range expansion fosters genetic segregation of the growing population with preferential access to nutrients and reduced mechanical restrictions for cells at the expanding periphery. Here we elucidate how localized conditions in cross-feeding bacterial communities shape community spatial organization. We combine experiments with an individual based mathematical model to resolve how trophic dependencies affect localized growth rates and nucleate successful cell lineages. The model tracks individual cell lineages and attributes these with trophic dependencies that promote counterintuitive reproductive advantages and result in lasting influences on the community structure, and potentially, on its functioning. We examine persistence of lucky lineages in structured habitats where expansion is interrupted by physical obstacles to gain insights into patterns in porous domains.
Collapse
Affiliation(s)
- Benedict Borer
- Department of Environmental Systems Science, ETH Zürich, 8092, Zürich, Switzerland.
| | - Davide Ciccarese
- Department of Environmental Systems Science, ETH Zürich, 8092, Zürich, Switzerland
- Department of Environmental Microbiology, Swiss Federal Institute of Aquatic Science and Technology (Eawag), 8600, Dübendorf, Switzerland
| | - David Johnson
- Department of Environmental Microbiology, Swiss Federal Institute of Aquatic Science and Technology (Eawag), 8600, Dübendorf, Switzerland
| | - Dani Or
- Department of Environmental Systems Science, ETH Zürich, 8092, Zürich, Switzerland
| |
Collapse
|
8
|
Yu Z, Shi D, Liu W, Meng Y, Meng F. Metabolome responses of Enterococcus faecium to acid shock and nitrite stress. Biotechnol Bioeng 2020; 117:3559-3571. [PMID: 32662876 DOI: 10.1002/bit.27497] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Revised: 06/26/2020] [Accepted: 07/08/2020] [Indexed: 01/21/2023]
Abstract
Enterococcus faecium is gaining increasing interest due to its virulence and tolerance to a range of stresses (e.g., acid shock and nitrite stress in human stomach). The chemical taxonomy and basic structural features of cellular metabolite can provide us a deeper understanding of bacterial tolerance at molecular level. Here, we used hierarchical classification and molecular composition analysis to investigate the metabolome responses of E. faecium to acid shock and nitrite stress. Our results showed that considerable high biodegradable compounds (e.g., dipeptides) were produced by E. faecium under acid shock, while nitrite stress induced the accumulations of some low biodegradable compounds (e.g., organoheterocyclic compounds and benzenoids). Complete genome analysis and metabolic pathway profiling suggested that E. faecium produced high biodegradable metabolites responsible for the proton-translocation and biofilm formation, which increase its tolerance to acid shock. Yet, the presence of low biodegradable metabolites due to the nitrite exposure could disturb the bacterial productions of surface proteins, and thus inhibiting biofilm formation. Our approach uncovered the hidden interactions between intracellular metabolites and exogenous stress, and will improve the understanding of host-microbe interactions.
Collapse
Affiliation(s)
- Zhong Yu
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou, China
| | - Dongchen Shi
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou, China
| | - Wencong Liu
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou, China
| | - Yabing Meng
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou, China
| | - Fangang Meng
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou, China
| |
Collapse
|
9
|
Bueno E, Pinedo V, Cava F. Adaptation of Vibrio cholerae to Hypoxic Environments. Front Microbiol 2020; 11:739. [PMID: 32425907 PMCID: PMC7212424 DOI: 10.3389/fmicb.2020.00739] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 03/30/2020] [Indexed: 01/02/2023] Open
Abstract
Bacteria can colonize virtually any environment on Earth due to their remarkable capacity to detect and respond quickly and adequately to environmental stressors. Vibrio cholerae is a cosmopolitan bacterium that inhabits a vast range of environments. The V. cholerae life cycle comprises diverse environmental and infective stages. The bacterium is found in aquatic ecosystems both under free-living conditions or associated with a wide range of aquatic organisms, and some strains are also capable of causing epidemics in humans. In order to adapt between environments, V. cholerae possesses a versatile metabolism characterized by the rapid cross-regulation of energy-producing pathways. Low oxygen concentration is a key environmental factor that governs V. cholerae physiology. This article reviews the metabolic plasticity that enables V. cholerae to thrive on low oxygen concentrations and its role in environmental and host adaptation.
Collapse
Affiliation(s)
- Emilio Bueno
- Laboratory for Molecular Infection Medicine Sweden, Department of Molecular Biology, Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden
| | | | - Felipe Cava
- Laboratory for Molecular Infection Medicine Sweden, Department of Molecular Biology, Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden
| |
Collapse
|
10
|
González-Camejo J, Montero P, Aparicio S, Ruano MV, Borrás L, Seco A, Barat R. Nitrite inhibition of microalgae induced by the competition between microalgae and nitrifying bacteria. WATER RESEARCH 2020; 172:115499. [PMID: 31978839 DOI: 10.1016/j.watres.2020.115499] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 01/07/2020] [Accepted: 01/09/2020] [Indexed: 06/10/2023]
Abstract
Outdoor microalgae cultivation systems treating anaerobic membrane bioreactor (AnMBR) effluents usually present ammonium oxidising bacteria (AOB) competition with microalgae for ammonium uptake, which can cause nitrite accumulation. In literature, nitrite effects over microalgae have shown controversial results. The present study evaluates the nitrite inhibition role in a microalgae-nitrifying bacteria culture. For this purpose, pilot- and lab-scale assays were carried out. During the continuous outdoor operation of the membrane photobioreactor (MPBR) plant, biomass retention time (BRT) of 2 d favoured AOB activity, which caused nitrite accumulation. This nitrite was confirmed to inhibit microalgae performance. Specifically, continuous 5-d lab-scale assays showed a reduction in the nitrogen recovery efficiency by 32, 42 and 80% when nitrite concentration in the culture accounted for 5, 10 and 20 mg N·L-1, respectively. On the contrary, short 30-min exposure to nitrite showed no significant differences in the photosynthetic activity of microalgae under nitrite concentrations of 0, 5, 10 and 20 mg N·L-1. On the other hand, when the MPBR plant was operated at 2.5-d BRT, the nitrite concentration was reduced to negligible values due to increasing activity of microalgae and nitrite oxidising bacteria (NOB). This allowed obtaining maximum MPBR performance; i.e. nitrogen recovery rate (NRR) and biomass productivity of 19.7 ± 3.3 mg N·L-1·d-1 and 139 ± 35 mg VSS·L-1·d-1, respectively; while nitrification rate (NOxR) reached the lowest value (13.5 ± 3.4 mg N·L-1·d-1). Long BRT of 4.5 d favoured NOB growth, avoiding nitrite inhibition. However, it implied a decrease in microalgae growth and the accumulation of nitrate in the MPBR effluent. Hence, it seems that optimum BRT has to be within the range 2-4.5 d in order to favour microalgae growth with respect to AOB and NOB.
Collapse
Affiliation(s)
- J González-Camejo
- CALAGUA - Unidad Mixta UV-UPV, Institut Universitari d'Investigació d'Enginyeria de l'Aigua i Medi Ambient - IIAMA, Universitat Politècnica de València, Camí de Vera s/n, 46022, Valencia, Spain.
| | - P Montero
- CALAGUA - Unidad Mixta UV-UPV, Institut Universitari d'Investigació d'Enginyeria de l'Aigua i Medi Ambient - IIAMA, Universitat Politècnica de València, Camí de Vera s/n, 46022, Valencia, Spain
| | - S Aparicio
- CALAGUA - Unidad Mixta UV-UPV, Departament d'Enginyeria Química, Universitat de València, Avinguda de la Universitat s/n, 46100, Burjassot, Valencia, Spain
| | - M V Ruano
- CALAGUA - Unidad Mixta UV-UPV, Departament d'Enginyeria Química, Universitat de València, Avinguda de la Universitat s/n, 46100, Burjassot, Valencia, Spain
| | - L Borrás
- CALAGUA - Unidad Mixta UV-UPV, Departament d'Enginyeria Química, Universitat de València, Avinguda de la Universitat s/n, 46100, Burjassot, Valencia, Spain
| | - A Seco
- CALAGUA - Unidad Mixta UV-UPV, Departament d'Enginyeria Química, Universitat de València, Avinguda de la Universitat s/n, 46100, Burjassot, Valencia, Spain
| | - R Barat
- CALAGUA - Unidad Mixta UV-UPV, Institut Universitari d'Investigació d'Enginyeria de l'Aigua i Medi Ambient - IIAMA, Universitat Politècnica de València, Camí de Vera s/n, 46022, Valencia, Spain
| |
Collapse
|
11
|
Duan H, Gao S, Li X, Ab Hamid NH, Jiang G, Zheng M, Bai X, Bond PL, Lu X, Chislett MM, Hu S, Ye L, Yuan Z. Improving wastewater management using free nitrous acid (FNA). WATER RESEARCH 2020; 171:115382. [PMID: 31855696 DOI: 10.1016/j.watres.2019.115382] [Citation(s) in RCA: 74] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 12/06/2019] [Accepted: 12/07/2019] [Indexed: 05/06/2023]
Abstract
Free nitrous acid (FNA), the protonated form of nitrite, has historically been an unwanted substance in wastewater systems due to its inhibition on a wide range of microorganisms. However, in recent years, advanced understanding of FNA inhibitory and biocidal effects on microorganisms has led to the development of a series of FNA-based applications that improve wastewater management practices. FNA has been used in sewer systems to control sewer corrosion and odor; in wastewater treatment to achieve carbon and energy efficient nitrogen removal; in sludge management to improve the sludge reduction and energy recovery; in membrane systems to address membrane fouling; and in wastewater algae systems to facilitate algae harvesting. This paper aims to comprehensively and critically review the current status of FNA-based applications in improving wastewater management. The underlying mechanisms of FNA inhibitory and biocidal effects are also reviewed and discussed. Knowledge gaps and current limitations of the FNA-based applications are identified; and perspectives on the development of FNA-based applications are discussed. We conclude that the FNA-based technologies have great potential for enhancing the performance of wastewater systems; however, further development and demonstration at larger scales are still required for their wider applications.
Collapse
Affiliation(s)
- Haoran Duan
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD, 4072, Australia; School of Chemical Engineering, The University of Queensland, St. Lucia, QLD, 4072, Australia
| | - Shuhong Gao
- Institute for Environmental Genomics, Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, 73019, United States
| | - Xuan Li
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Nur Hafizah Ab Hamid
- School of Chemical Engineering, The University of Queensland, St. Lucia, QLD, 4072, Australia
| | - Guangming Jiang
- School of Civil, Mining and Environmental Engineering, University of Wollongong, Wollongong, NSW, 2522, Australia
| | - Min Zheng
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Xue Bai
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Philip L Bond
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Xuanyu Lu
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD, 4072, Australia; School of Chemical Engineering, The University of Queensland, St. Lucia, QLD, 4072, Australia
| | - Mariella M Chislett
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Shihu Hu
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Liu Ye
- School of Chemical Engineering, The University of Queensland, St. Lucia, QLD, 4072, Australia
| | - Zhiguo Yuan
- Advanced Water Management Centre, The University of Queensland, St Lucia, QLD, 4072, Australia.
| |
Collapse
|
12
|
Lin L, Pratt S, Rattier M, Ye L. Individual and combined effect of salinity and nitrite on freshwater Anammox bacteria (FAB). WATER RESEARCH 2020; 169:114931. [PMID: 31669901 DOI: 10.1016/j.watres.2019.114931] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 06/13/2019] [Accepted: 07/29/2019] [Indexed: 06/10/2023]
Abstract
Anaerobic ammonium oxidation (Anammox) based technology has potential for nitrogen removal from wastewater with high salinity, but both salt and nitrite (a substrate for Anammox) have negative effect on microbial activity. In order to achieve Anammox in saline wastewater treatment, it is essential to understand the combined effect of these two components. In this study, the individual and combined effect of salinity and nitrite on fixed film freshwater Anammox bacteria (FAB, mainly belonging to the Ca. Brocadia genus), enriched on carriers from a 1500 L pilot scale one-stage (PN/Anammox) moving bed bioreactor (MBBR), were systematically investigated by 57 pre-designed batch tests. The combined inhibition of nitrite and salinity was determined by comparing with additive and independent inhibition models. With salinity only, the specific Anammox activity (SAA) decreased with increasing salinity: 14.6 mS/cm (about 9.1 g NaCl/L) of salinity caused 50% inhibition (IC50). With nitrite only, SAA started to decrease when nitrite concentration was above 450 mg N/L (threshold) and decreased with increased nitrite (IC50 = 666 mg N/L) thereafter. Significantly, when both salinity and nitrite were elevated, both the threshold and IC50 of nitrite were reduced, with inhibition enhanced. Analysis showed that at high salinity (>14.6 mS/cm) and nitrite concentration (>666 mg N/L), inhibition was close to that predicted by simulation of additive and independent inhibition models. Within a salinity range of 4-14.6 mS/cm and nitrite concentration range of 50-666 mg N/L, the combined inhibition was more severe than prediction (p < 0.05) based on the additive and independent inhibition models and therefore it was determined to be synergistic inhibition.
Collapse
Affiliation(s)
- Limin Lin
- School of Chemical Engineering, The University of Queensland, St. Lucia, Brisbane, QLD, 4072, Australia
| | - Steven Pratt
- School of Chemical Engineering, The University of Queensland, St. Lucia, Brisbane, QLD, 4072, Australia
| | - Maxime Rattier
- School of Chemical Engineering, The University of Queensland, St. Lucia, Brisbane, QLD, 4072, Australia
| | - Liu Ye
- School of Chemical Engineering, The University of Queensland, St. Lucia, Brisbane, QLD, 4072, Australia.
| |
Collapse
|
13
|
Arce‐Rodríguez A, Volke DC, Bense S, Häussler S, Nikel PI. Non-invasive, ratiometric determination of intracellular pH in Pseudomonas species using a novel genetically encoded indicator. Microb Biotechnol 2019; 12:799-813. [PMID: 31162835 PMCID: PMC6559197 DOI: 10.1111/1751-7915.13439] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 05/14/2019] [Accepted: 05/15/2019] [Indexed: 11/30/2022] Open
Abstract
The ability of Pseudomonas species to thrive in all major natural environments (i.e. terrestrial, freshwater and marine) is based on its exceptional capability to adapt to physicochemical changes. Thus, environmental bacteria have to tightly control the maintenance of numerous physiological traits across different conditions. The intracellular pH (pHi ) homoeostasis is a particularly important feature, since the pHi influences a large portion of the biochemical processes in the cell. Despite its importance, relatively few reliable, easy-to-implement tools have been designed for quantifying in vivo pHi changes in Gram-negative bacteria with minimal manipulations. Here we describe a convenient, non-invasive protocol for the quantification of the pHi in bacteria, which is based on the ratiometric fluorescent indicator protein PHP (pH indicator for Pseudomonas). The DNA sequence encoding PHP was thoroughly adapted to guarantee optimal transcription and translation of the indicator in Pseudomonas species. Our PHP-based quantification method demonstrated that pHi is tightly regulated over a narrow range of pH values not only in Pseudomonas, but also in other Gram-negative bacterial species such as Escherichia coli. The maintenance of the cytoplasmic pH homoeostasis in vivo could also be observed upon internal (e.g. redirection of glucose consumption pathways in P. putida) and external (e.g. antibiotic exposure in P. aeruginosa) perturbations, and the PHP indicator was also used to follow dynamic changes in the pHi upon external pH shifts. In summary, our work describes a reliable method for measuring pHi in Pseudomonas, allowing for the detailed investigation of bacterial pHi homoeostasis and its regulation.
Collapse
Affiliation(s)
- Alejandro Arce‐Rodríguez
- Department of Molecular BacteriologyHelmholtz Centre for Infection Research38124BraunschweigGermany
| | - Daniel C. Volke
- The Novo Nordisk Foundation Center for BiosustainabilityTechnical University of Denmark2800Kongens LyngbyDenmark
| | - Sarina Bense
- Department of Molecular BacteriologyHelmholtz Centre for Infection Research38124BraunschweigGermany
| | - Susanne Häussler
- Department of Molecular BacteriologyHelmholtz Centre for Infection Research38124BraunschweigGermany
| | - Pablo I. Nikel
- The Novo Nordisk Foundation Center for BiosustainabilityTechnical University of Denmark2800Kongens LyngbyDenmark
| |
Collapse
|
14
|
Lilja EE, Johnson DR. Substrate cross-feeding affects the speed and trajectory of molecular evolution within a synthetic microbial assemblage. BMC Evol Biol 2019; 19:129. [PMID: 31221104 PMCID: PMC6584980 DOI: 10.1186/s12862-019-1458-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Accepted: 06/11/2019] [Indexed: 12/11/2022] Open
Abstract
Background Substrate cross-feeding occurs when one organism partially consumes a primary substrate into one or more metabolites while other organisms then consume the metabolites. While pervasive within microbial communities, our knowledge about the effects of substrate cross-feeding on microbial evolution remains limited. To address this knowledge gap, we experimentally evolved isogenic nitrite (NO2−) cross-feeding microbial strains together for 700 generations, identified genetic changes that were acquired over the evolution experiment, and compared the results with an isogenic completely denitrifying strain that was evolved alone for 700 generations. We further investigated how the magnitude of interdependence between the nitrite cross-feeding strains affects the main outcomes. Our main objective was to quantify how substrate cross-feeding and the magnitude of interdependence affect the speed and trajectory of molecular evolution. Results We found that each nitrite (NO2−) cross-feeding strain acquired fewer genetic changes than did the completely denitrifying strain. In contrast, pairs of nitrite cross-feeding strains together acquired more genetic changes than did the completely denitrifying strain. Moreover, nitrite cross-feeding promoted population diversification, as pairs of nitrite cross-feeding strains acquired a more varied set of genetic changes than did the completely denitrifying strain. These outcomes likely occurred because nitrite cross-feeding enabled the co-existence of two distinct microbial strains, thus increasing the amount of genetic variation for selection to act upon. Finally, the nitrite cross-feeding strains acquired different types of genetic changes than did the completely denitrifying strain, indicating that nitrite cross-feeding modulates the trajectory of molecular evolution. Conclusions Our results demonstrate that substrate cross-feeding can affect both the speed and trajectory of molecular evolution within microbial populations. Substrate cross-feeding can therefore have potentially important effects on the life histories of microorganisms. Electronic supplementary material The online version of this article (10.1186/s12862-019-1458-4) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Elin E Lilja
- Department of Environmental Systems Science, ETH Zürich, 8092, Zürich, Switzerland.,Department of Environmental Microbiology, Eawag, Überlandstrasse 133, 8600, Dübendorf, Switzerland.,Present address: School of Physics and Astronomy, University of Edinburgh, Edinburgh, EH9 3FD, UK
| | - David R Johnson
- Department of Environmental Microbiology, Eawag, Überlandstrasse 133, 8600, Dübendorf, Switzerland.
| |
Collapse
|
15
|
Shi ZJ, Xu LZJ, Wu D, Cheng YF, Zhang FY, Liao SM, Zhang ZZ, He MM, Jin RC. Anammox granule as new inoculum for start-up of anaerobic sulfide oxidation (ASO) process and its reverse start-up. CHEMOSPHERE 2019; 217:279-288. [PMID: 30419382 DOI: 10.1016/j.chemosphere.2018.11.035] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 10/07/2018] [Accepted: 11/03/2018] [Indexed: 06/09/2023]
Abstract
The feasibility of implementing anaerobic ammonium oxidation (anammox) granules to start up high-loading anaerobic sulfide oxidation (ASO) in an upflow anaerobic sludge bed (UASB) reactor was investigated. An innovation method of the reverse start-up of anammox was also validated. Firstly, the reactor was operated to treat sulfide-rich wastewaters into which nitrite was introduced as an electron acceptor. An high-rate performance with sulfide and nitrate removal rates of 105.5 ± 0.11 kg S m-3 d-1 and 28.45 ± 3.40 kg N m-3 d-1, respectively, was accomplished. Sulfurovum were enriched with the increase of the substrate load and then conquered Candidatus Kuenenia to be the predominant bacteria. Excitation-emission matrix (EEM) spectroscopy showed that the intensities of fluorescence decreased and protein-like substrates were the main components associated with the process of start-up. FT-IR analysis found that the main functional groups indicator were O-H groups. Secondly, the reverse start-up of anammox (achieving 90% TN removal) was achieved immediately when the substrate changed. 16S rRNA analysis indicated the successfully enrichment of anammox bacteria (Candidatus Kuenenia). These results suggest that anammox granules can act as inoculum of high-loading ASO process and the reverse start-up provides a new perspective for the fast initiation of anammox process.
Collapse
Affiliation(s)
- Zhi-Jian Shi
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310036, China; Key Laboratory of Hangzhou City for Ecosystem Protection and Restoration, Hangzhou Normal University, Hangzhou, 310036, China
| | - Lian-Zeng-Ji Xu
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310036, China; Key Laboratory of Hangzhou City for Ecosystem Protection and Restoration, Hangzhou Normal University, Hangzhou, 310036, China
| | - Dan Wu
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310036, China; Key Laboratory of Hangzhou City for Ecosystem Protection and Restoration, Hangzhou Normal University, Hangzhou, 310036, China
| | - Ya-Fei Cheng
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310036, China; Key Laboratory of Hangzhou City for Ecosystem Protection and Restoration, Hangzhou Normal University, Hangzhou, 310036, China
| | - Fu-Yue Zhang
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310036, China
| | - Si-Mo Liao
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310036, China
| | - Zheng-Zhe Zhang
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310036, China; Key Laboratory of Hangzhou City for Ecosystem Protection and Restoration, Hangzhou Normal University, Hangzhou, 310036, China
| | - Miao-Miao He
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310036, China; Key Laboratory of Hangzhou City for Ecosystem Protection and Restoration, Hangzhou Normal University, Hangzhou, 310036, China.
| | - Ren-Cun Jin
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, 310036, China; Key Laboratory of Hangzhou City for Ecosystem Protection and Restoration, Hangzhou Normal University, Hangzhou, 310036, China.
| |
Collapse
|
16
|
He S, Chen Y, Qin M, Mao Z, Yuan L, Niu Q, Tan X. Effects of temperature on anammox performance and community structure. BIORESOURCE TECHNOLOGY 2018; 260:186-195. [PMID: 29625291 DOI: 10.1016/j.biortech.2018.03.090] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Revised: 03/13/2018] [Accepted: 03/17/2018] [Indexed: 06/08/2023]
Abstract
A lab-scale anammox up-flow anaerobic sludge blanket (UASB) reactor was run to investigate the influence of temperature on anammox performance and community structure. The anammox system had a higher substrate tolerance at 13 °C than at 18 °C. The adverse effects caused by the use of a lower temperature (8 °C) could be restored. The nitrogen removal rate (NRR) decreased with decreasing in situ specific anammox activity (SAA). Interestingly, the ex situ SAA acclimated at 23 °C, when exposed to ex situ temperatures of 33 and 28 °C, was higher than for those acclimated at 33 and 28 °C. No shift was observed in the optimum temperature for ex situ SAA in the whole lowering process of anammox UASB. More extracellular polymeric substances were produced in response to cooler conditions (18 °C and 13 °C). Ca. Kuenenia became much more abundant (55.18% of the microbial community) and had a competitive advantage over other anammox bacteria (AnAOB) at 13 °C.
Collapse
Affiliation(s)
- Shilong He
- School of Environment and Spatial Informatics, China University of Mining & Technology, Xuzhou 221116, China.
| | - Yi Chen
- School of Environment and Spatial Informatics, China University of Mining & Technology, Xuzhou 221116, China
| | - Meng Qin
- School of Environment and Spatial Informatics, China University of Mining & Technology, Xuzhou 221116, China
| | - Zhen Mao
- School of Environment and Spatial Informatics, China University of Mining & Technology, Xuzhou 221116, China
| | - Limei Yuan
- School of Environment and Spatial Informatics, China University of Mining & Technology, Xuzhou 221116, China
| | - Qigui Niu
- School of Environmental Science and Engineering, Shandong University, No. 27 Shanda South Road, Jinan 250100, China
| | - Xicheng Tan
- School of Environment and Spatial Informatics, China University of Mining & Technology, Xuzhou 221116, China
| |
Collapse
|
17
|
Rathnayake RMLD, Oshiki M, Ishii S, Segawa T, Satoh H, Okabe S. Experimental Evidence for in Situ Nitric Oxide Production in Anaerobic Ammonia-Oxidizing Bacterial Granules. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:5744-5752. [PMID: 29678110 DOI: 10.1021/acs.est.8b00876] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Although nitric oxide (NO) emissions from anaerobic ammonium oxidation (anammox)-based processes were reported previously, the NO production pathways are poorly understood. Here, we investigated the NO production pathways in anammox granules in detail by combining 15N-stable isotope tracer experiments with various inhibitors, microsensor measurements, and transcriptome analysis for key genes of NO2- reduction. NO was emitted from the anammox granules, which account for 0.07% of the N2 emission. 15N-stable isotope-tracer experiments indicated that most of the N2 was produced by anammox bacteria, whereas NO was produced from NO2- reduction by anammox and denitrifying bacteria. The NO emission rate was highest at pH 8.0 and accelerated by increasing NH4+ and NO2- concentrations in the culture media. The microsensor analyses showed the in situ NO production rate was highest in the outer layer of the anammox granule where anammox activity was also highest. The detected in situ NO concentrations of up to 2.7 μM were significantly above physiological thresholds known to affect a wide range of microorganisms present in wastewater. Hence, NO likely plays pivotal roles in the microbial interactions in anammox granules, which needs to be further investigated.
Collapse
Affiliation(s)
- Rathnayake M L D Rathnayake
- Department of Civil Engineering, Faculty of Engineering , University of Peradeniya , Peradeniya 20400 , Sri Lanka
- Division of Environmental Engineering, Graduate School of Engineering , Hokkaido University , North-13, West-8 , Sapporo 060-8628 , Japan
| | - Mamoru Oshiki
- Division of Environmental Engineering, Graduate School of Engineering , Hokkaido University , North-13, West-8 , Sapporo 060-8628 , Japan
- Department of Civil Engineering , National Institute of Technology, Nagaoka College , 888 Nishikatakaimachi , Nagaoka , Niigata 940-8532 , Japan
| | - Satoshi Ishii
- Division of Environmental Engineering, Graduate School of Engineering , Hokkaido University , North-13, West-8 , Sapporo 060-8628 , Japan
- Department of Soil, Water and Climate , University of Minnesota , 439 Borlaug Hall, 1991 Upper Buford Circle , St. Paul , Minnesota 55108 , United States
- BioTechnology Institute , University of Minnesota , 140 Gortner Laboratory, 1479 Gortner Avenue , St. Paul , Minnesota 55108 , United States
| | - Takahiro Segawa
- Center for Life Science Research , University of Yamanashi , 1110, Shimokato , Chuo , Yamanashi 409-3898 , Japan
- Transdisciplinary Research Integration Center , National Institute of Polar Research , 10-3 Midori-cho , Tachikawa , Tokyo 190-8518 , Japan
| | - Hisashi Satoh
- Division of Environmental Engineering, Graduate School of Engineering , Hokkaido University , North-13, West-8 , Sapporo 060-8628 , Japan
| | - Satoshi Okabe
- Division of Environmental Engineering, Graduate School of Engineering , Hokkaido University , North-13, West-8 , Sapporo 060-8628 , Japan
| |
Collapse
|
18
|
Wang J, Zhang Z, Ye X, Huang F, Chen S. Performance and mechanism of free nitrous acid on the solubilization of waste activated sludge. RSC Adv 2018; 8:15897-15905. [PMID: 35542244 PMCID: PMC9080090 DOI: 10.1039/c8ra01951g] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 04/17/2018] [Indexed: 11/21/2022] Open
Abstract
Free nitrous acid (FNA) is a promising chemical reagent for excess sludge reduction. The distinctive properties of FNA treatment on waste activated sludge (WAS) disposal have previously been demonstrated, however, the cellular response, permeabilization, and disruption caused by low-concentration FNA and the direct cell solubilization of WAS using concentrated FNA should be better understood. In this study, the parameters that influence the sludge solubilization efficiency were optimized over a wide range of FNA concentrations. The sludge solubilization efficiency was found to be superior when the sludge was exposed to FNA (when the dosage of NaNO2 was 0.12 g g-1 TSS and the pH was 3.0, FNA = 20.94 mg L-1) for 10 h at 25 °C, and the TSS removal and COD dissolution efficiencies were found to be prominent at 38% and 7%, respectively. In the FNA treatment of WAS, some FNA-tolerable cells increased the K+, Ca2+, and H+ effluxes under low concentrations of FNA, and finally achieved ion homeostasis based on the results using a scanning ion-selective electrode measurement technique. This could cause the cells in WAS to maintain cytoactivity and integrity under a low-concentration FNA treatment. Furthermore, flow cytometry was used to assess the permeabilization and disruption of sludge cells toward a concentration gradient of FNA. Flow cytometry results indicated that cells in sludge flocs were disrupted within 30 minutes when the FNA concentration was above 8 mg L-1.
Collapse
Affiliation(s)
- Jinsong Wang
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences Xiamen 361021 China +86 0592 6190977 +86 0592 6190529
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Zhaoji Zhang
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences Xiamen 361021 China +86 0592 6190977 +86 0592 6190529
| | - Xin Ye
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences Xiamen 361021 China +86 0592 6190977 +86 0592 6190529
| | - Fuyi Huang
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences Xiamen 361021 China +86 0592 6190977 +86 0592 6190529
| | - Shaohua Chen
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences Xiamen 361021 China +86 0592 6190977 +86 0592 6190529
| |
Collapse
|
19
|
Kuperman RG, Minyard ML, Checkai RT, Sunahara GI, Rocheleau S, Dodard SG, Paquet L, Hawari J. Inhibition of soil microbial activity by nitrogen-based energetic materials. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2017; 36:2981-2990. [PMID: 28519901 DOI: 10.1002/etc.3862] [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: 04/14/2017] [Accepted: 05/15/2017] [Indexed: 06/07/2023]
Abstract
We investigated individual toxicities of the nitrogen-based energetic materials (EMs) 2,4-dinitrotoluene (2,4-DNT); 2-amino-4,6-dinitrotoluene (2-ADNT); 4-amino-2,6-dinitrotoluene (4-ADNT); and nitroglycerin (NG) on microbial activity in Sassafras sandy loam (SSL) soil, which has physicochemical characteristics that support very high qualitative relative bioavailability for organic chemicals. Batches of SSL soil for basal respiration (BR) and substrate-induced respiration (SIR) assays were separately amended with individual EMs or acetone carrier control. Total microbial biomass carbon (biomass C) was determined from CO2 production increases after addition of 2500 mg/kg of glucose-water slurry to the soil. Exposure concentrations of each EM in soil were determined using US Environmental Protection Agency method 8330A. Basal respiration was the most sensitive endpoint for assessing the effects of nitroaromatic EMs on microbial activity in SSL, whereas SIR and biomass C were more sensitive endpoints for assessing the effects of NG in soil. The orders of toxicity (from greatest to least) were 4-ADNT > 2,4-DNT = 2-ADNT > NG for BR; but for SIR and biomass C, the order of toxicity was NG > 2,4-DNT > 2-ADNT = 4-ADNT. No inhibition of SIR was found up to and including the greatest concentration of each ADNT tested in SSL. These ecotoxicological data will be helpful in identifying concentrations of contaminant EMs in soil that present acceptable ecological risks for biologically mediated processes in soil. Environ Toxicol Chem 2017;36:2981-2990. Published 2017 Wiley Periodicals Inc. on behalf of SETAC.This article is a US government work and, as such, is in the public domain in the United States of America.
Collapse
Affiliation(s)
- Roman G Kuperman
- US Army Edgewood Chemical Biological Center, Aberdeen Proving Ground, Maryland, USA
| | | | - Ronald T Checkai
- US Army Edgewood Chemical Biological Center, Aberdeen Proving Ground, Maryland, USA
| | | | | | - Sabine G Dodard
- National Research Council of Canada, Montréal, Quebec, Canada
| | - Louise Paquet
- National Research Council of Canada, Montréal, Quebec, Canada
| | - Jalal Hawari
- Polytechnique de Montréal, Montréal, Quebec, Canada
| |
Collapse
|
20
|
Metabolite toxicity slows local diversity loss during expansion of a microbial cross-feeding community. ISME JOURNAL 2017; 12:136-144. [PMID: 28914879 DOI: 10.1038/ismej.2017.147] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 06/30/2017] [Accepted: 07/12/2017] [Indexed: 02/02/2023]
Abstract
Metabolic interactions between populations can influence patterns of spatial organization and diversity within microbial communities. Cross-feeding is one type of metabolic interaction that is pervasive within microbial communities, where one genotype consumes a resource into a metabolite while another genotype then consumes the metabolite. A typical feature of cross-feeding is that the metabolite may impose toxicity if it accumulates to sufficient concentrations. However, little is known about the effect of metabolite toxicity on spatial organization and local diversity within microbial communities. We addressed this knowledge gap by experimentally varying the toxicity of a single cross-fed metabolite and measuring the consequences on a synthetic microbial cross-feeding community. Our results demonstrate that metabolite toxicity slows demixing and thus slows local diversity loss of the metabolite-producing population. Using mathematical modeling, we show that this is because toxicity slows growth, which enables more cells to emigrate from the founding region and contribute towards population expansion. Our results show that metabolite toxicity is an important factor affecting local diversity within microbial communities and that spatial organization can be affected by non-intuitive mechanisms.
Collapse
|
21
|
Lilja EE, Johnson DR. Metabolite toxicity determines the pace of molecular evolution within microbial populations. BMC Evol Biol 2017; 17:52. [PMID: 28196465 PMCID: PMC5310025 DOI: 10.1186/s12862-017-0906-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 02/06/2017] [Indexed: 11/11/2022] Open
Abstract
Background The production of toxic metabolites has shaped the spatial and temporal arrangement of metabolic processes within microbial cells. While diverse solutions to mitigate metabolite toxicity have evolved, less is known about how evolution itself is affected by metabolite toxicity. We hypothesized that the pace of molecular evolution should increase as metabolite toxicity increases. At least two mechanisms could cause this. First, metabolite toxicity could increase the mutation rate. Second, metabolite toxicity could increase the number of available mutations with large beneficial effects that selection could act upon (e.g., mutations that provide tolerance to toxicity), which consequently would increase the rate at which those mutations increase in frequency. Results We tested this hypothesis by experimentally evolving the bacterium Pseudomonas stutzeri under denitrifying conditions. The metabolite nitrite accumulates during denitrification and has pH-dependent toxic effects, which allowed us to evolve P. stutzeri at different magnitudes of nitrite toxicity. We demonstrate that increased nitrite toxicity results in an increased pace of molecular evolution. We further demonstrate that this increase is generally due to an increased number of available mutations with large beneficial effects and not to an increased mutation rate. Conclusions Our results demonstrate that the production of toxic metabolites can have important impacts on the evolutionary processes of microbial cells. Given the ubiquity of toxic metabolites, they could also have implications for understanding the evolutionary histories of biological organisms. Electronic supplementary material The online version of this article (doi:10.1186/s12862-017-0906-2) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Elin E Lilja
- Department of Environmental Microbiology, Eawag, Überlandstrasse 133, 8600, Dübendorf, Switzerland.,Department of Environmental Systems Science, ETH Zürich, Zürich, Switzerland
| | - David R Johnson
- Department of Environmental Microbiology, Eawag, Überlandstrasse 133, 8600, Dübendorf, Switzerland.
| |
Collapse
|
22
|
Segregating metabolic processes into different microbial cells accelerates the consumption of inhibitory substrates. ISME JOURNAL 2016; 10:1568-78. [PMID: 26771930 DOI: 10.1038/ismej.2015.243] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 11/16/2015] [Accepted: 11/23/2015] [Indexed: 11/08/2022]
Abstract
Different microbial cell types typically specialize at performing different metabolic processes. A canonical example is substrate cross-feeding, where one cell type consumes a primary substrate into an intermediate and another cell type consumes the intermediate. While substrate cross-feeding is widely observed, its consequences on ecosystem processes is often unclear. How does substrate cross-feeding affect the rate or extent of substrate consumption? We hypothesized that substrate cross-feeding eliminates competition between different enzymes and reduces the accumulation of growth-inhibiting intermediates, thus accelerating substrate consumption. We tested this hypothesis using isogenic mutants of the bacterium Pseudomonas stutzeri that either completely consume nitrate to dinitrogen gas or cross-feed the intermediate nitrite. We demonstrate that nitrite cross-feeding eliminates inter-enzyme competition and, in turn, reduces nitrite accumulation. We further demonstrate that nitrite cross-feeding accelerates substrate consumption, but only when nitrite has growth-inhibiting effects. Knowledge about inter-enzyme competition and the inhibitory effects of intermediates could therefore be important for deciding how to best segregate different metabolic processes into different microbial cell types to optimize a desired biotransformation.
Collapse
|
23
|
Mohamed MS, Tan JS, Kadkhodaei S, Mohamad R, Mokhtar MN, Ariff AB. Kinetics and modeling of microalga Tetraselmis sp. FTC 209 growth with respect to its adaptation toward different trophic conditions. Biochem Eng J 2014. [DOI: 10.1016/j.bej.2014.04.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
24
|
Carvajal-Arroyo JM, Puyol D, Li G, Sierra-Álvarez R, Field JA. The role of pH on the resistance of resting- and active anammox bacteria to NO2- inhibition. Biotechnol Bioeng 2014; 111:1949-56. [PMID: 24771200 DOI: 10.1002/bit.25269] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2014] [Revised: 03/13/2014] [Accepted: 04/15/2014] [Indexed: 11/08/2022]
Abstract
The anaerobic oxidation of ammonium (anammox) uses nitrite as terminal electron acceptor. The nitrite can cause inhibition to the bacteria that catalyze the anammox reaction. The literature shows a great divergence on the levels of NO2 (-) causing inhibition. Moreover, the conditions influencing the resistance of anammox bacteria to NO2 (-) inhibitory effect are not well understood. This work investigated the effect of the pH and the concentration of nitrite on the activity and metabolism of anammox granular sludge under different physiological conditions. Batch activity tests in a range of pH values were carried out in which either actively metabolizing cells or resting cells were exposed to nitrite in the presence or absence of the electron donating substrate ammonium, respectively. The response of the bacteria was evaluated by analyzing the specific anammox activity, the accumulation of nitric oxide, and the evolution of the ATP content in the biomass. Additionally, the effect of the pH on the tolerance of the biomass to single substrate feeding interruptions was evaluated in continuous anammox bioreactors. The results show that the influence of the pH on the NO2 (-) inhibition of anammox bacteria is greater under non-metabolizing conditions than during active metabolism. The exposure of resting cells to NO2 (-) (100 mg N L(-1) ) at pH values below 7.2 caused complete inhibition of the anammox activity. The inhibition was accompanied by accumulation of the intermediate, nitric oxide, in the gas phase. In contrast, just mild inhibition was observed for resting cells exposed to the same NO2 (-) concentration at pH values higher than 7.5 or any of the pH values tested in assays with actively metabolizing cells. ATP initially increased and subsequently decreased in time after resting cells were exposed to NO2 (-) suggesting an active response of the cells to nitrite stress. Furthermore, bioreactors operated at pH lower than 6.8 had greater sensitivity to NO2 (-) during an ammonium feed interruption than a bioreactor operated at pH 7.1. The results suggest that the ability of resting cells to tolerate NO2 (-) inhibition is seriously impeded at mildly acidic pH values; whereas actively metabolizing biomass is resistant to NO2 (-) toxicity over a wide range of pH values.
Collapse
Affiliation(s)
- José M Carvajal-Arroyo
- Department of Chemical and Environmental Engineering, University of Arizona, P.O. Box 210011, Tucson, Arizona.
| | | | | | | | | |
Collapse
|
25
|
Carvajal-Arroyo JM, Puyol D, Li G, Lucero-Acuña A, Sierra-Álvarez R, Field JA. Pre-exposure to nitrite in the absence of ammonium strongly inhibits anammox. WATER RESEARCH 2014; 48:52-60. [PMID: 24091185 DOI: 10.1016/j.watres.2013.09.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Revised: 08/31/2013] [Accepted: 09/05/2013] [Indexed: 06/02/2023]
Abstract
Anaerobic ammonium oxidizing bacteria (Anammox) are known to be inhibited by their substrate, nitrite. However, the mechanism of inhibition and the physiological conditions under which nitrite impacts the performance of anammox bioreactors are still unknown. This study investigates the role of pre-exposing anammox bacteria to nitrite alone on their subsequent activity and metabolism after ammonium has been added. Batch experiments were carried out with anammox granular biofilm pre-exposed to nitrite over a range of concentrations and durations in the absence of ammonium. The effect of pre-exposure to nitrite alone compared to nitrite simultaneously fed with ammonium was evaluated by measuring the anammox activity and the accumulation of the intermediate, nitric oxide. The results show that the inhibitory effect was more dramatic when bacteria were pre-exposed to nitrite in absence of ammonium, as revealed by the lower activity and the higher accumulation of nitric oxide. The nitrite concentration causing 50% inhibition was 53 and 384 mg N L(-1) in the absence or the presence of ammonium, respectively. The nitrite inhibition was thus 7.2-fold more severe in the absence of ammonium. Biomass exposure to nitrite (25 mg N L(-1)), in absence of ammonium, led to accumulation of nitric oxide. On the other hand when the biomass was exposed to nitrite in presence of ammonium, accumulation of nitric oxide was only observed at much higher nitrite concentrations (500 mg N L(-1)). The inhibitory effect of nitrite in the absence of ammonium was very rapid. The rate of decay of the anammox activity was equivalent to the diffusion rate of nitrite up to 46% of activity loss. The results taken as a whole suggest that nitrite inhibition is more acute when anammox cells are not actively metabolizing. Accumulation of nitric oxide in the headspace most likely indicates disruption of the anammox biochemistry by nitrite inhibition, caused by an interruption of the hydrazine synthesis step.
Collapse
Affiliation(s)
- José M Carvajal-Arroyo
- Department of Chemical and Environmental Engineering, University of Arizona, P.O. Box 210011, Tucson, AZ, USA.
| | | | | | | | | | | |
Collapse
|
26
|
Cao X, Qian D, Meng X. Effects of pH on nitrite accumulation during wastewater denitrification. ENVIRONMENTAL TECHNOLOGY 2013; 34:45-51. [PMID: 23530314 DOI: 10.1080/09593330.2012.679700] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The characteristics of nitrite accumulation during denitrification in mixed liquors with different pH values were studied. The mixed liquors were prepared by adding acclimated denitrifying activated sludge to synthetic wastewater with methanol (CH3OH) as the carbon source (chemical oxygen demand = 600 mg/L) and sodium nitrate (NaNO3) as the nitrogen source (NO3(-)-N = 50 mg/L). The results showed that the pH during denitrification could be kept constant using buffer solutions composed of KH2PO4, Na2HPO4 x 12H2O and Na2B4O7 x 10H2O. Nitrite accumulation was more serious at low pH than at high pH, regardless of whether the pH of the mixed liquor was stabilized during denitrification. The specific rates of nitrate and nitrite reduction were both inhibited by increased pH. The specific rate of nitrate reduction was more vulnerable than that of nitrite reduction to higher pH. Nitrite accumulation during these experiments resulted from different reduction rates for nitrate and nitrite. Nitrite reduction rates were inhibited by the presence of nitrate, which stimulated nitrite accumulation during denitrification.
Collapse
Affiliation(s)
- Xiangsheng Cao
- Key Laboratory of Beijing for Water Quality Science and Water Environmental Restoration Engineering, College of Civil Engineering, Beijing University of Technology, Beijing, China.
| | | | | |
Collapse
|
27
|
Zhou Y, Oehmen A, Lim M, Vadivelu V, Ng WJ. The role of nitrite and free nitrous acid (FNA) in wastewater treatment plants. WATER RESEARCH 2011; 45:4672-82. [PMID: 21762944 DOI: 10.1016/j.watres.2011.06.025] [Citation(s) in RCA: 233] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2011] [Revised: 06/17/2011] [Accepted: 06/21/2011] [Indexed: 05/06/2023]
Abstract
Nitrite is known to accumulate in wastewater treatment plants (WWTPs) under certain environmental conditions. The protonated form of nitrite, free nitrous acid (FNA), has been found to cause severe inhibition to numerous bioprocesses at WWTPs. However, this inhibitory effect of FNA may possibly be gainfully exploited, such as repressing nitrite oxidizing bacteria (NOB) growth to achieve N removal via the nitrite shortcut. However, the inhibition threshold of FNA to repress NOB (∼0.02 mg HNO2-N/L) may also inhibit other bioprocesses. This paper reviews the inhibitory effects of FNA on nitrifiers, denitrifiers, anammox bacteria, phosphorus accumulating organisms (PAO), methanogens, and other microorganisms in populations used in WWTPs. The possible inhibition mechanisms of FNA on microorganisms are discussed and compared. It is concluded that a single inhibition mechanism is not sufficient to explain the negative impacts of FNA on microbial metabolisms and that multiple inhibitory effects can be generated from FNA. The review would suggest further research is necessary before the FNA inhibition mechanisms can be more effectively used to optimize WWTP bioprocesses. Perspectives on research directions, how the outcomes may be used to manipulate bioprocesses and the overall implications of FNA on WWTPs are also discussed.
Collapse
Affiliation(s)
- Yan Zhou
- Advanced Environmental Biotechnology Centre (AEBC), Nanyang Environment and Water Research Institute (NEWRI), Nanyang Technological University, School of Biological Science, Level N-B2-01, 60 Nanyang Avenue, Singapore 639798, Singapore.
| | | | | | | | | |
Collapse
|
28
|
Nitrite effect on ammonium and nitrite oxidizing processes in a nitrifying sludge. World J Microbiol Biotechnol 2010. [DOI: 10.1007/s11274-010-0573-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
|
29
|
Denitrification response patterns during the transition to anoxic respiration and posttranscriptional effects of suboptimal pH on nitrous [corrected] oxide reductase in Paracoccus denitrificans. Appl Environ Microbiol 2010; 76:6387-96. [PMID: 20709842 DOI: 10.1128/aem.00608-10] [Citation(s) in RCA: 119] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Denitrification in soil is a major source of atmospheric N(2)O. Soil pH appears to exert a strong control on the N(2)O/N(2) product ratio (high ratios at low pH), but the reasons for this are not well understood. To explore the possible mechanisms involved, we conducted an in-depth investigation of the regulation of denitrification in the model organism Paracoccus denitrificans during transition to anoxia both at pH 7 and when challenged with pHs ranging from 6 to 7.5. The kinetics of gas transformations (O(2), NO, N(2)O, and N(2)) were monitored using a robotic incubation system. Combined with quantification of gene transcription, this yields high-resolution data for direct response patterns to single factors. P. denitrificans demonstrated robustly balanced transitions from O(2) to nitric oxide-based respiration, with NO concentrations in the low nanomolar range and marginal N(2)O production at an optimal pH of 7. Transcription of nosZ (encoding N(2)O reductase) preceded that of nirS and norB (encoding nitrite and NO reductase, respectively) by 5 to 7 h, which was confirmed by observed reduction of externally supplied N(2)O. Reduction of N(2)O was severely inhibited by suboptimal pH. The relative transcription rates of nosZ versus nirS and norB were unaffected by pH, and low pH had a moderate effect on the N(2)O reductase activity in cells with a denitrification proteome assembled at pH 7. We thus concluded that the inhibition occurred during protein synthesis/assembly rather than transcription. The study shed new light on the regulation of the environmentally essential N(2)O reductase and the important role of pH in N(2)O emission.
Collapse
|
30
|
Free nitrous acid (FNA) inhibition on denitrifying poly-phosphate accumulating organisms (DPAOs). Appl Microbiol Biotechnol 2010; 88:359-69. [PMID: 20668845 DOI: 10.1007/s00253-010-2780-3] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2010] [Revised: 07/10/2010] [Accepted: 07/11/2010] [Indexed: 10/19/2022]
Abstract
Free nitrous acid (FNA) has been identified to be a ubiquitous inhibitor of a wide range of microorganisms, including bacteria involved in wastewater treatment. The FNA-induced inhibition on the anoxic (nitrite as electron acceptor) metabolism of denitrifying poly-phosphate accumulating organisms (DPAOs) was investigated using sludge from a sequencing batch reactor performing carbon, nitrogen, and phosphorus removal from synthetic wastewater. We found that FNA had a much stronger inhibitory effect on phosphorus (P) uptake and glycogen production than on poly-beta-hydroxyalkanoate degradation and nitrite reduction. The intracellular adenosine triphosphate levels decreased sharply during the FNA incubation, and the decreasing rates were positively correlated with increasing FNA concentrations. The electron transport activity of DPAOs when exposed to FNA displayed a similar trend. Further, at FNA concentrations above 0.044 mg HNO(2)-N/L, the anaerobic metabolism of DPAOs was initiated despite of the presence of nitrite, as evidenced by the release of phosphorus and the consumption of glycogen. DPAO metabolism did not recover completely from FNA inhibition in the subsequent FNA-free environment. The recovery rate depended on the concentration of FNA applied in the previous anoxic period. These results suggest that the inhibitory effects are diverse and may be attributable to different mechanisms operating simultaneously.
Collapse
|
31
|
Ma J, Yang Q, Wang S, Wang L, Takigawa A, Peng Y. Effect of free nitrous acid as inhibitors on nitrate reduction by a biological nutrient removal sludge. JOURNAL OF HAZARDOUS MATERIALS 2010; 175:518-523. [PMID: 19910113 DOI: 10.1016/j.jhazmat.2009.10.036] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2009] [Revised: 09/13/2009] [Accepted: 10/10/2009] [Indexed: 05/28/2023]
Abstract
Nitrite has been commonly thought to have a broad inhibitory effect on bacterial metabolism. Little is known about the impact of nitrite on nitrate reduction with pH considered as an important factor. This study investigates the nitrite inhibition on nitrate reduction during denitrification under various pH conditions by using a biological nutrient removal (BNR) sludge. The results showed that nitrate reduction performance had a much stronger relationship with the free nitrous acid (FNA) than that of nitrite concentration, implying that FNA, rather than nitrite, is likely the real inhibitor on nitrate reduction. The nitrate reduction activity of the biomass was observed to be inhibited about 60% in the range of 0.01-0.025 mg HNO(2)-N/L and was totally inhibited when FNA level was greater than the threshold concentration (0.2mg HNO(2)-N/L). Moreover, the recovery rate from inhibitory effect was found to be dependent much more strongly on the concentration of FNA, of which the biomass was exposed to during the inhibition period, than on the duration of the inhibition and the feeding mode of inhibitor. It was also found that nitrite reduction was significantly inhibited by FNA and the nitrite reduction rate was linear to nitrate reduction rate due to the inhibitory mechanism under which FNA may react with the enzymes involved in the denitrification process.
Collapse
Affiliation(s)
- Juan Ma
- Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing 100124, China
| | | | | | | | | | | |
Collapse
|
32
|
Zhou Y, Pijuan M, Yuan Z. Free nitrous acid inhibition on anoxic phosphorus uptake and denitrification by poly-phosphate accumulating organisms. Biotechnol Bioeng 2007; 98:903-12. [PMID: 17486651 DOI: 10.1002/bit.21458] [Citation(s) in RCA: 108] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Nitrite has been found in previous research an inhibitor on anoxic phosphorus uptake in enhanced biological phosphorus removal systems (EBPR). However, the inhibiting nitrite concentration reported varied in a large range. This study investigates the nitrite inhibition on anoxic phosphorus uptake by using four different mixed cultures performing EBPR with pH considered an important factor. The results showed that the protonated species of nitrite, HNO(2) (or free nitrous acid, FNA), rather than nitrite, is likely the actual inhibitor on the anoxic phosphorus uptake, as revealed by the much stronger correlation of the phosphorus uptake rate with the FNA than with the nitrite concentration. All the four EBPR sludges showed decreased anoxic phosphorus uptake rates with increased FNA concentrations in the studied range of 0.002-0.02 mg HNO(2)-N/L. The phosphorus uptake by all four cultures was completely inhibited at 0.02 mg HNO(2)-N/L. Granular sludge appeared to be more tolerant to HNO(2) than flocular sludge likely due to its stronger resistance to the transfer of nitrite into the bacterial aggregates. Furthermore, denitrification by the phosphorus-accumulating organisms (PAOs) was also found to be inhibited by HNO(2). The denitrification rate decreased by approximately 40% when the FNA concentration was increased from 0.002 to 0.02 mg HNO(2)-N/L.
Collapse
Affiliation(s)
- Yan Zhou
- Advanced Wastewater Management Centre (AWMC), The University of Queensland, St Lucia, Brisbane, Qld 4072, Australia
| | | | | |
Collapse
|
33
|
Peng Y, Zhu G. Biological nitrogen removal with nitrification and denitrification via nitrite pathway. Appl Microbiol Biotechnol 2006; 73:15-26. [PMID: 17028876 DOI: 10.1007/s00253-006-0534-z] [Citation(s) in RCA: 286] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2006] [Revised: 06/01/2006] [Accepted: 06/05/2006] [Indexed: 10/24/2022]
Abstract
Presently, the wastewater treatment practices can be significantly improved through the introduction of new microbial treatment technologies. To meet increasingly stringent discharge standards, new applications and control strategies for the sustainable removal of ammonium from wastewater have to be implemented. Partial nitrification to nitrite was reported to be technically feasible and economically favorable, especially when wastewater with high ammonium concentrations or low C/N ratios is treated. For successful implementation of the technology, the critical point is how to maintain partial nitrification of ammonium to nitrite. Partial nitrification can be obtained by selectively inhibiting nitrite oxidizing bacteria through appropriate regulation of the system's DO concentration, microbial SRT, pH, temperature, substrate concentration and load, operational and aeration pattern, and inhibitor. The review addressed the microbiology, its consequences for their application, the current status regarding application, and the future developments.
Collapse
Affiliation(s)
- Yongzhen Peng
- School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin, 150090, China.
| | | |
Collapse
|
34
|
Weon SY, Lee CW, Lee SI, Koopman B. Nitrite inhibition of aerobic growth of Acinetobacter sp. WATER RESEARCH 2002; 36:4471-4476. [PMID: 12418649 DOI: 10.1016/s0043-1354(02)00185-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Nitrite inhibition of Acinetobacter sp. growing under aerobic conditions was studied. Specific growth rates under non-limiting concentrations of acetate and dissolved oxygen averaged 0.62h(-1). Growth and phosphate uptake by Acinetobacter sp. were both inhibited by increasing nitrite concentrations. The median inhibitory concentration (IC50) of free nitrous acid (FNA) was 0.10 mg/L and the IC10 of FNA was 0.05 mg/L. Removing nitrite from cultures reversed the inhibitory effect. Comparison of the IC10 of FNA for Acinetobacter sp. to inhibitory concentrations for other wastewater heterotrophic bacteria suggests that Acinetobacter sp. are relatively sensitive to this compound.
Collapse
Affiliation(s)
- Seung-Yeon Weon
- Department of Environment Engineering Sciences, University of Florida, Gainesville 32611, USA
| | | | | | | |
Collapse
|
35
|
Serafim LS, Lemos PC, Levantesi C, Tandoi V, Santos H, Reis MAM. Methods for detection and visualization of intracellular polymers stored by polyphosphate-accumulating microorganisms. J Microbiol Methods 2002; 51:1-18. [PMID: 12069885 DOI: 10.1016/s0167-7012(02)00056-8] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Polyphosphate-accumulating microorganisms (PAOs) are important in enhanced biological phosphorus (P) removal. Considerable effort has been devoted to understanding the biochemical nature of enhanced biological phosphorus removal (EBPR) and it has been shown that intracellular polymer storage plays an important role in PAO's metabolism. The storage capacity of PAOs gives them a competitive advantage over other microorganisms present that are not able to accumulate internal reserves. Intracellular polymers stored by PAOs include polyphosphate (poly-P), polyhydroxyalkanoates (PHAs) and glycogen. Staining procedures for qualitative visualization of polymers by optical microscopy and combinations of these procedures with molecular tools for in situ identification are described here. The strengths and weaknesses of widely used polymer quantification methods that require destruction of samples, are also discussed. Finally, the potential of in vivo nuclear magnetic resonance (NMR) spectroscopy for on-line measurement of intracellular reserves is reported.
Collapse
Affiliation(s)
- Luísa S Serafim
- Departamento de Química, CQFB/REQUIMTE, FCT/Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
| | | | | | | | | | | |
Collapse
|
36
|
Roca C, Olsson L. Dynamic responses of Pseudomonas fluorescens DF57 to nitrogen or carbon source addition. J Biotechnol 2001; 86:39-50. [PMID: 11223143 DOI: 10.1016/s0168-1656(00)00401-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Cultures of Pseudomonas fluorescens DF57 were grown on different carbon and nitrogen sources. Glucose, succinate and acetate were used as carbon source and pulsed to an aerobic steady-state cultivation of P. fluorescens DF57 at D = 0.1 h(-1) with citrate as limiting carbon source. Glucose was utilised with the fastest uptake rate (19.4 C mmol l(-1) h(-1)) compared to succinate (8.8 C mmol l(-1) h(-1)) and acetate (4.3 C mmol l(-1) h(-1)). Acetate triggered an inhibition of cellular metabolism, which resulted in 2-h long growth arrest after its addition to the steady-state culture. The influence of the nitrogen source was investigated in an aerobic cultivation on a mixture of ammonium and nitrate as limiting nitrogen sources and citrate as non-limiting carbon source. When ammonia and nitrate were pulsed to the steady-state culture, they were mainly assimilated into biomass with a maximum uptake rate of 111 and 33 mg N l(-1) h(-1), respectively. Nitrate uptake was never complete as the residual concentration in the chemostat cultivation was 30 mg N l(-1) nitrate. A pulse of nitrite in the cultivation broth resulted in an inhibition of the growth but not of the primary metabolism, as nitrite was taken up at 38 mg N l(-1) h(-1), citrate was consumed and cofactors were produced continuously. In all experiments, oxygen was used as electron acceptor.
Collapse
Affiliation(s)
- C Roca
- Department of Biotechnology, Center for Process Biotechnology, Building 223, Technical University of Denmark, DK-2800, Lyngby, Denmark
| | | |
Collapse
|
37
|
Neves AR, Ramos A, Nunes MC, Kleerebezem M, Hugenholtz J, de Vos WM, Almeida J, Santos H. In vivo nuclear magnetic resonance studies of glycolytic kinetics in Lactococcus lactis. Biotechnol Bioeng 1999; 64:200-12. [PMID: 10397856 DOI: 10.1002/(sici)1097-0290(19990720)64:2<200::aid-bit9>3.0.co;2-k] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The metabolism of glucose by nongrowing cells of L. lactis strain MG5267 was studied under controlled conditions of pH, temperature, and gas atmosphere (anaerobic and aerobic) using a circulating system coupled to nuclear magnetic resonance (NMR) detection that allowed a noninvasive determination of intracellular pools of intermediate metabolites by 13C-NMR with a time resolution of 30 seconds. In addition, intracellular parameters, such as pH, NTP levels, and concentration of inorganic phosphate in the cytoplasm, could be monitored on-line by 31P-NMR with a time resolution of approx. 3 min. The time course for the concentrations of intracellular fructose 1,6-bisphosphate (FBP), 3-phosphoglycerate (3-PGA), and phosphoenolpyruvate (PEP), together with kinetic measurements of substrate consumption and endproducts formation, were used as a basis for the construction of a mechanistic model for glycolysis. In vivo measurements were complemented with determinations of phosphorylated metabolites in perchloric acid extracts. A top-down model was developed by simplifying the metabolism to the resolution allowed by the experimental data collected by in vivo NMR (grouped in seven metabolic steps). This simplified mechanistic model was adjusted to the metabolite concentrations determined by in vivo NMR. The results obtained led to the rationalization of the dynamics of glucose metabolism as being driven largely by ATP surplus. This excess causes accumulation of FBP due to NAD+ limitation, whose regeneration is dependent on downstream pyruvate reduction. The model was capable of predicting qualitative shifts in the metabolism of glucose when changing from anaerobic to aerobic conditions.
Collapse
Affiliation(s)
- A R Neves
- Instituto de Tecnologia Química e Biológica and Instituto de Biologia Experimental e Tecnológica, Universidade Nova de Lisboa, Rua da Quinta Grande, 6, Apt. 127, 2780 Oeiras, Portugal
| | | | | | | | | | | | | | | |
Collapse
|
38
|
Effects of carbon substrates on nitrite accumulation in freshwater sediments. Appl Environ Microbiol 1999; 65:61-6. [PMID: 9872760 PMCID: PMC90983 DOI: 10.1128/aem.65.1.61-66.1999] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The contribution of the biochemical pathways nitrification, denitrification, and dissimilatory NO3- reduction to NH4+ (DNRA) to the accumulation of NO2- in freshwaters is governed by the species compositions of the bacterial populations resident in the sediments, available carbon (C) and nitrogen (N) substrates, and environmental conditions. Recent studies of major rivers in Northern Ireland have shown that high NO2- concentrations found in summer, under warm, slow-flowing conditions, arise from anaerobic NO3- reduction. Locally, agricultural pollutants entering rivers are important C and N sources, providing ideal substrates for the aquatic bacteria involved in cycling of N. In this study a range of organic C compounds commonly found in agricultural pollutants were provided as energy sources in 48-h incubation experiments to investigate if the chemical compositions of the pollutants affected which NO3- reduction pathway was followed and influenced subsequent NO2- accumulation. Carbon stored within the sediments was sufficient to support DNRA and denitrifier populations, and the resulting NO2- peak (80 &mgr;g of N liter-1 [approximate]) observed at 24 h was indicative of the simultaneous activities of both bacterial groups. The value of glycine as an energy source for denitrification or DNRA appeared to be limited, but glycine was an important source of additional N. Glucose was an efficient substrate for both the denitrification and DNRA pathways, with a NO2- peak of 160 &mgr;g of N liter-1 noted at 24 h. Addition of formate and acetate stimulated continuous NO2- production throughout the 48-h period, caused by partial inhibition of the denitrification pathway. The formate treatment resulted in a high NO2- accumulation (1,300 &mgr;g of N liter-1 [approximate]), and acetate treatment resulted in a low NO2- concentration (<100 &mgr;g of N liter-1).
Collapse
|
39
|
Accashian JV, Vinopal RT, Kim BJ, Smets BF. Aerobic growth on nitroglycerin as the sole carbon, nitrogen, and energy source by a mixed bacterial culture. Appl Environ Microbiol 1998; 64:3300-4. [PMID: 9726874 PMCID: PMC106724 DOI: 10.1128/aem.64.9.3300-3304.1998] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Nitroglycerin (glycerol trinitrate [GTN]), an explosive and vasodilatory compound, was metabolized by mixed microbial cultures from aeration tank sludge previously exposed to GTN. Aerobic enrichment cultures removed GTN rapidly in the absence of a supplemental carbon source. Complete denitration of GTN, provided as the sole C and N source, was observed in aerobic batch cultures and proceeded stepwise via the dinitrate and mononitrate isomers, with successive steps occurring at lower rates. The denitration of all glycerol nitrate esters was found to be concomitant, and 1, 2-glycerol dinitrate (1,2-GDN) and 2-glycerol mononitrate (2-GMN) were the primary GDN and GMN isomers observed. Denitration of GTN resulted in release of primarily nitrite-N, indicating a reductive denitration mechanism. Biomass growth at the expense of GTN was verified by optical density and plate count measurements. The kinetics of GTN biotransformation were 10-fold faster than reported for complete GTN denitration under anaerobic conditions. A maximum specific growth rate of 0.048 +/- 0.005 h-1 (mean +/- standard deviation) was estimated for the mixed culture at 25 degreesC. Evidence of GTN toxicity was observed at GTN concentrations above 0. 3 mM. To our knowledge, this is the first report of complete denitration of GTN used as a primary growth substrate by a bacterial culture under aerobic conditions.
Collapse
Affiliation(s)
- J V Accashian
- Environmental Engineering Program, Department of Civil and Environmental Engineering, University of Connecticut, Storrs, Connecticut 06269-2037, USA
| | | | | | | |
Collapse
|