1
|
Sun H, Jiang S. A review on nirS-type and nirK-type denitrifiers via a scientometric approach coupled with case studies. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2022; 24:221-232. [PMID: 35072673 DOI: 10.1039/d1em00518a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The denitrification process plays an important role in improving water quality and is a source/sink of nitrous oxide to the atmosphere. The second important rate-limiting step of the denitrification process is catalyzed by two enzymes with different structures and unrelated evolutionary relationships, namely, the Cu-type nitrite reductase encoded by the nirK gene and the cytochrome cd1-type nitrite reductase encoded by the nirS gene. Although some relevant reviews have been published on denitrifiers, most of these reviews do not include statistical analysis, and do not compare the nirS and nirK communities in-depth. However, a systematic study of the nirS-type and nirK-type denitrifying communities and their response to environmental factors in different ecosystems is needed. In this review, a scientometric approach combined with case studies was used to study the nirS-type and nirK-type denitrifiers. The scientometric approach demonstrated that Pseudomonas, Paracoccus, and Thauera are the most frequently mentioned nirS-type denitrifiers, while Pseudomonas and Bradyrhizobium are the top two most frequently mentioned nirK-type denitrifiers. Among various environmental factors, the concentrations of nitrite, nitrate and carbon sources were widely reported factors that can influence the abundance and structure of nirS-type and nirK-type denitrifying communities. Case studies indicated that Bradyrhizobium was the major genus detected by high-throughput sequencing in both nirS and nirK-type denitrifiers in soil systems. nirS-type denitrifiers are more sensitive to the soil type, soil moisture, pH, and rhizosphere effect than nirK. To clarify the relationships between denitrifying communities and environmental factors, the DNA stable isotope probe combined with metagenomic sequencing is needed for new denitrifier detections.
Collapse
Affiliation(s)
- Haishu Sun
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shanxue Jiang
- School of Ecology and Environment, Beijing Technology and Business University, Beijing 100048, China.
| |
Collapse
|
2
|
Anderson E, Jang J, Venterea R, Feyereisen G, Ishii S. Isolation and characterization of denitrifiers from woodchip bioreactors for bioaugmentation application. J Appl Microbiol 2020; 129:590-600. [DOI: 10.1111/jam.14655] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 02/28/2020] [Accepted: 03/27/2020] [Indexed: 12/13/2022]
Affiliation(s)
- E.L. Anderson
- Department of Soil, Water, and Climate University of Minnesota St. Paul MN USA
| | - J. Jang
- BioTechnology Institute University of Minnesota St. Paul MN USA
| | - R.T. Venterea
- Department of Soil, Water, and Climate University of Minnesota St. Paul MN USA
- USDA‐ARS Soil and Water Management Research Unit St. Paul MN USA
| | - G.W. Feyereisen
- USDA‐ARS Soil and Water Management Research Unit St. Paul MN USA
| | - S. Ishii
- Department of Soil, Water, and Climate University of Minnesota St. Paul MN USA
- BioTechnology Institute University of Minnesota St. Paul MN USA
| |
Collapse
|
3
|
Chee-Sanford JC, Connor L, Krichels A, Yang WH, Sanford RA. Hierarchical detection of diverse Clade II (atypical) nosZ genes using new primer sets for classical- and multiplex PCR array applications. J Microbiol Methods 2020; 172:105908. [PMID: 32234512 DOI: 10.1016/j.mimet.2020.105908] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 03/25/2020] [Accepted: 03/25/2020] [Indexed: 11/27/2022]
Abstract
The reduction of nitrous oxide (N2O) to N2 represents the key terminal step in canonical denitrification. Nitrous oxide reductase (NosZ), the enzyme associated with this biological step, however, is not always affiliated with denitrifying microorganisms. Such organisms were shown recently to possess a Clade II (atypical) nosZ gene, in contrast to Clade I (typical) nosZ harbored in more commonly studied denitrifiers. Subsequent phylogenetic analyses have shown that Clade II NosZ are affiliated with a much broader diversity of microorganisms than those with Clade I NosZ, the former including both non-denitrifiers and denitrifiers. Most studies attempting to characterize the nosZ gene diversity using DNA-based PCR approaches have only focused on Clade I nosZ, despite recent metagenomic sequencing studies that have demonstrated the dominance of Clade II nosZ genes in many ecosystems, particularly soil. As a result, these studies have greatly underestimated the genetic potential for N2O reduction present in ecosystems. Because the high diversity of Clade II NosZ makes it impossible to design a universal primer set that would effectively amplify all nosZ genes in this clade, we developed a suite of primer sets to specifically target seven of ten designated subclades of Clade II nosZ genes. The new primer sets yield suitable product sizes for paired end amplicon sequencing and qPCR, demonstrated here in their use for both conventional single-reaction and multiplex array platforms. In addition, we show the utility of these primers for detecting nosZ gene transcripts from mRNA extracted from soil.
Collapse
Affiliation(s)
| | | | - Alexander Krichels
- Program in Ecology, Evolution, and Conservation Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Wendy H Yang
- Program in Ecology, Evolution, and Conservation Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA; Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA; Department of Geology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Robert A Sanford
- Department of Geology, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
| |
Collapse
|
4
|
Liu X, Li Z, Zhang C, Tan X, Yang X, Wan C, Lee DJ. Enhancement of anaerobic degradation of petroleum hydrocarbons by electron intermediate: Performance and mechanism. BIORESOURCE TECHNOLOGY 2020; 295:122305. [PMID: 31675520 DOI: 10.1016/j.biortech.2019.122305] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 10/16/2019] [Accepted: 10/18/2019] [Indexed: 06/10/2023]
Abstract
A quinone-respiring strain capable of degrading multitudinous petroleum hydrocarbons was isolated by selective medium and identified as Bacillus sp. (named as C8). Maximum 76.7% of total petroleum hydrocarbons (TPH) were degraded by the biosurfactant-mediated C8 with the aid of nitrate and electron intermediate (anthraquinone-2,6-disulphonate, AQDS). The quantitative real-time PCR results of several intracellular key functional genes suggested that AQDS could participate in the transformation of intermediates and accelerate the electron transfer in the degradation of TPH and nitrate, thereby eliminating the accumulation of nitrite and increasing the degradation efficiency of TPH. A strengthening mechanism, which promoted electron transport in the anaerobic denitrification degradation of petroleum hydrocarbons by quinone-respiring strain with the aid of electron intermediate, was proposed. The influencing factors were evaluated by using response surface methodology, and the TPH removal was positively related to temperature but negatively to pH.
Collapse
Affiliation(s)
- Xiang Liu
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200438, China
| | - Zhengwen Li
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200438, China
| | - Chen Zhang
- Shanghai Municipal Engineering Design General Institute, Shanghai 200092, China
| | - Xuejun Tan
- Shanghai Municipal Engineering Design General Institute, Shanghai 200092, China
| | - Xue Yang
- Shanghai Municipal Engineering Design General Institute, Shanghai 200092, China
| | - Chunli Wan
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200438, China.
| | - Duu-Jong Lee
- Department of Chemical Engineering, National Taiwan University, Taipei 106, Taiwan; Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan
| |
Collapse
|
5
|
|
6
|
Ma Y, Zilles JL, Kent AD. An evaluation of primers for detecting denitrifiers via their functional genes. Environ Microbiol 2019; 21:1196-1210. [PMID: 30724437 DOI: 10.1111/1462-2920.14555] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 01/29/2019] [Accepted: 02/01/2019] [Indexed: 12/11/2022]
Abstract
Microbial populations provide nitrogen cycling ecosystem services at the nexus of agriculture, environmental quality and climate change. Denitrification, in particular, impacts socio-environmental systems in both positive and negative ways, through reduction of aquatic and atmospheric nitrogen pollution, but also reduction of soil fertility and production of greenhouse gases. However, denitrification rates are quite variable in time and space, and therefore difficult to model. Microbial ecology is working to improve the predictive ecology of denitrifiers by quantifying and describing the diversity of microbial functional groups. However, metagenomic sequencing has revealed previously undescribed diversity within these functional groups, and highlighted a need to reevaluate coverage of existing DNA primers for denitrification functional genes. We provide here a comprehensive in silico evaluation of primer sets that target diagnostic genes in the denitrification pathway. This analysis makes use of current DNA sequence data available for each functional gene. It contributes a comparative analysis of the strengths and limitations of each primer set for describing denitrifier functional groups. This analysis identifies genes for which development of new tools is needed, and aids in interpretation of existing datasets, both of which will facilitate application of molecular methods to further develop the predictive ecology of denitrifiers.
Collapse
Affiliation(s)
- Yanjun Ma
- Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Julie L Zilles
- Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Angela D Kent
- Department of Natural Resources and Environmental Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| |
Collapse
|
7
|
Igielski S, Kjellerup BV, Davis AP. Understanding urban stormwater denitrification in bioretention internal water storage zones. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2019; 91:32-44. [PMID: 30682230 DOI: 10.2175/106143017x15131012188024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 07/10/2018] [Indexed: 06/09/2023]
Abstract
Conventional free-draining bioretention systems promote nitrate production and continual leaching to receiving waters. In this study, laboratory tests demonstrated the efficacy of an internal water storage zone (IWSZ) to target nitrate removal via denitrification. Experimental results confirmed that the carbon substrate characteristics (Willow Oak woodchip media) and the hydraulic retention time of nitrified stormwater affected nitrate removal performance. A 2.6-day batch treatment time reduced 3.0 mg-N/L to <0.01 mg/L, corresponding to a first-order denitrification rate constant of 0.0011 min-1 . Under various flow conditions, the associated hydraulic retention time may be used as a predictive measurement of nitrate removal performance. Scanning electron microscopy and 16S rRNA analysis of the woodchips showed that biofilms were present that could be responsible for anaerobic lignocellulose degradation and denitrification. This knowledge, along with evaluation of the biofilm community composition, reinforced the notion of a heterogeneous structure due to nutrient availability and hydrodynamic conditions. PRACTITIONER POINTS: Denitrification can occur using woodchips in a bioretention internal water storage zone. The denitrification rate is slow and may be limited during field-scale applications. A woodchip pretreatment did not provide long-term enhancement to the denitrification rate. Denitrification bacteria were found in the internal water storage zone.
Collapse
Affiliation(s)
- Sara Igielski
- Department of Civil and Environmental Engineering, University of Maryland, College Park, MD, USA
| | - Birthe V Kjellerup
- Department of Civil and Environmental Engineering, University of Maryland, College Park, MD, USA
| | - Allen P Davis
- Department of Civil and Environmental Engineering, University of Maryland, College Park, MD, USA
| |
Collapse
|
8
|
Genomics and Ecology of Novel N 2O-Reducing Microorganisms. Trends Microbiol 2017; 26:43-55. [PMID: 28803698 DOI: 10.1016/j.tim.2017.07.003] [Citation(s) in RCA: 185] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Revised: 06/29/2017] [Accepted: 07/14/2017] [Indexed: 11/22/2022]
Abstract
Microorganisms with the capacity to reduce the greenhouse gas nitrous oxide (N2O) to harmless dinitrogen gas are receiving increased attention due to increasing N2O emissions (and our need to mitigate climate change) and to recent discoveries of novel N2O-reducing bacteria and archaea. The diversity of denitrifying and nondenitrifying microorganisms with capacity for N2O reduction was recently shown to be greater than previously expected. A formerly overlooked group (clade II) in the environment include a large fraction of nondenitrifying N2O reducers, which could be N2O sinks without major contribution to N2O formation. We review the recent advances about fundamental understanding of the genomics, physiology, and ecology of N2O reducers and the importance of these findings for curbing N2O emissions.
Collapse
|
9
|
Coyotzi S, Doxey AC, Clark ID, Lapen DR, Van Cappellen P, Neufeld JD. Agricultural soil denitrifiers possess extensive nitrite reductase gene diversity. Environ Microbiol 2017; 19:1189-1208. [PMID: 27943515 DOI: 10.1111/1462-2920.13643] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 11/04/2016] [Accepted: 12/03/2016] [Indexed: 11/27/2022]
Abstract
Denitrification transforms nitrogen applied as fertilizer and emits N2 O, which is a potent greenhouse gas. Very little is known about the identities of abundant and active denitrifiers in agricultural soils. We coupled DNA stable-isotope probing (DNA-SIP) with flow-through reactors (FTRs) to detect active agricultural soil denitrifiers. The FTRs were incubated with nitrate and 13 C6 -glucose under anoxic conditions and sampled at multiple time points. Labelled DNA from active microorganisms was analyzed by 16S rRNA gene fingerprinting, amplicon and shotgun metagenomic sequencing. Taxonomic representation of heavy fractions was consistent across sites and time points, including Betaproteobacteria (71%; Janthinobacterium, Acidovorax, Azoarcus and Dechloromonas), Alphaproteobacteria (8%; Rhizobium), Gammaproteobacteria (4%; Pseudomonas) and Actinobacteria (4%; Streptomycetaceae). Most nitrite-reductase reads from heavy DNA annotated to the copper-containing form (nirK). Assigned taxonomies of active denitrifiers based on reads matching the nirK gene were comparable to those obtained through nitric oxide (norB) and RNA polymerase (rpoB) annotations but not the nitrous oxide reductase gene (nosZ). Analysis of recovered metagenomes from heavy DNA demonstrated extensive nirK sequence family diversity, including novel taxonomic groups that are not captured by existing primers.
Collapse
Affiliation(s)
- Sara Coyotzi
- Department of Biology, University of Waterloo, Waterloo, ON, N2L 3G1, Canada
| | - Andrew C Doxey
- Department of Biology, University of Waterloo, Waterloo, ON, N2L 3G1, Canada
| | - Ian D Clark
- Department of Earth Sciences, University of Ottawa, Ottawa, ON, K1N 6N5, Canada
| | - David R Lapen
- Agriculture and Agri-Food Canada, Ottawa, ON, K1A 0C6, Canada
| | - Philippe Van Cappellen
- Department of Earth and Environmental Sciences, Water Institute, University of Waterloo, Waterloo, ON, N2L 3G1, Canada
| | - Josh D Neufeld
- Department of Biology, University of Waterloo, Waterloo, ON, N2L 3G1, Canada
| |
Collapse
|
10
|
Design and evaluation of primers targeting genes encoding NO-forming nitrite reductases: implications for ecological inference of denitrifying communities. Sci Rep 2016; 6:39208. [PMID: 27966627 PMCID: PMC5155301 DOI: 10.1038/srep39208] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 11/17/2016] [Indexed: 12/20/2022] Open
Abstract
The detection of NO-forming nitrite reductase genes (nir) has become the standard when studying denitrifying communities in the environment, despite well-known amplification biases in available primers. We review the performance of 35 published and 121 newly designed primers targeting the nirS and nirK genes, against sequences from complete genomes and 47 metagenomes from three major habitats where denitrification is important. There were no optimal universal primer pairs for either gene, although published primers targeting nirS displayed up to 75% coverage. The alternative is clade-specific primers, which show a trade-off between coverage and specificity. The test against metagenomic datasets showed a distinct performance of primers across habitats. The implications of clade-specific nir primers choice and their performance for ecological inference when used for quantitative estimates and in sequenced-based community ecology studies are discussed and our phylogenomic primer evaluation can be used as a reference along with their environmental specificity as a guide for primer selection. Based on our results, we also propose a general framework for primer evaluation that emphasizes the testing of coverage and phylogenetic range using full-length sequences from complete genomes, as well as accounting for environmental range using metagenomes. This framework serves as a guideline to simplify primer performance comparisons while explicitly addressing the limitations and biases of the primers evaluated.
Collapse
|
11
|
Implications of Limited Thermophilicity of Nitrite Reduction for Control of Sulfide Production in Oil Reservoirs. Appl Environ Microbiol 2016; 82:4190-4199. [PMID: 27208132 DOI: 10.1128/aem.00599-16] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Accepted: 04/28/2016] [Indexed: 01/15/2023] Open
Abstract
UNLABELLED Nitrate reduction to nitrite in oil fields appears to be more thermophilic than the subsequent reduction of nitrite. Concentrated microbial consortia from oil fields reduced both nitrate and nitrite at 40 and 45°C but only nitrate at and above 50°C. The abundance of the nirS gene correlated with mesophilic nitrite reduction activity. Thauera and Pseudomonas were the dominant mesophilic nitrate-reducing bacteria (mNRB), whereas Petrobacter and Geobacillus were the dominant thermophilic NRB (tNRB) in these consortia. The mNRB Thauera sp. strain TK001, isolated in this study, reduced nitrate and nitrite at 40 and 45°C but not at 50°C, whereas the tNRB Petrobacter sp. strain TK002 and Geobacillus sp. strain TK003 reduced nitrate to nitrite but did not reduce nitrite further from 50 to 70°C. Testing of 12 deposited pure cultures of tNRB with 4 electron donors indicated reduction of nitrate in 40 of 48 and reduction of nitrite in only 9 of 48 incubations. Nitrate is injected into high-temperature oil fields to prevent sulfide formation (souring) by sulfate-reducing bacteria (SRB), which are strongly inhibited by nitrite. Injection of cold seawater to produce oil creates mesothermic zones. Our results suggest that preventing the temperature of these zones from dropping below 50°C will limit the reduction of nitrite, allowing more effective souring control. IMPORTANCE Nitrite can accumulate at temperatures of 50 to 70°C, because nitrate reduction extends to higher temperatures than the subsequent reduction of nitrite. This is important for understanding the fundamentals of thermophilicity and for the control of souring in oil fields catalyzed by SRB, which are strongly inhibited by nitrite.
Collapse
|
12
|
Xu W, Wu D, Wang J, Huang X, Xie B. Effects of oxygen and carbon content on nitrogen removal capacities in landfill bioreactors and response of microbial dynamics. Appl Microbiol Biotechnol 2016; 100:6427-6434. [PMID: 27005414 DOI: 10.1007/s00253-016-7460-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Revised: 03/08/2016] [Accepted: 03/09/2016] [Indexed: 10/22/2022]
Abstract
In this study, landfill bioreactors were tested to treat the recalcitrant leachate-nitrogen and the impacts of relevant operational parameters on its conversion were comprehensively investigated. We found that the highly diverse microbial community in landfill bioreactors could be substantially affected by increasing biodegradable carbon and oxygen content, which led to the whole system's intrinsic nitrogen removal capacity increasing from 50 to 70 %, and meanwhile, the contribution of anammox was detected less than 20 %. The sequencing and q-PCR results showed that microbial community in bioreactor was dominated by Proteobacteria (∼35 %) and Acidobacteria (~20 %) during the whole experiment. The abundance of anammox functioning bacteria (Amx) kept at a stable level (-2.5 to -2.2 log (copies/16S rRNA)) and was not statistically correlated to the abundance of anammox bacteria. However, significant linear correlation (p < 0.05) was determined between the abundance of nirS and Proteobacteria; amoA and AOB. Redundancy analysis (RDA) suggested that although oxygen and biodegradable carbon can both impose effects on microbial community structure, only biodegradable carbon content is the determinant in the total nitrogen removal.
Collapse
Affiliation(s)
- Weiqing Xu
- Key Laboratory for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Science; Joint Research Institute for New Energy and the Environment (East China Normal University and Colorado State University), East China Normal University, 500 Dong Chuan Road, Shanghai, 200241, People's Republic of China
| | - Dong Wu
- Key Laboratory for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Science; Joint Research Institute for New Energy and the Environment (East China Normal University and Colorado State University), East China Normal University, 500 Dong Chuan Road, Shanghai, 200241, People's Republic of China
| | - Jie Wang
- Key Laboratory for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Science; Joint Research Institute for New Energy and the Environment (East China Normal University and Colorado State University), East China Normal University, 500 Dong Chuan Road, Shanghai, 200241, People's Republic of China
| | - Xinghua Huang
- Key Laboratory for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Science; Joint Research Institute for New Energy and the Environment (East China Normal University and Colorado State University), East China Normal University, 500 Dong Chuan Road, Shanghai, 200241, People's Republic of China
| | - Bing Xie
- Key Laboratory for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Science; Joint Research Institute for New Energy and the Environment (East China Normal University and Colorado State University), East China Normal University, 500 Dong Chuan Road, Shanghai, 200241, People's Republic of China.
| |
Collapse
|
13
|
Highly diverse nirK genes comprise two major clades that harbour ammonium-producing denitrifiers. BMC Genomics 2016; 17:155. [PMID: 26923558 PMCID: PMC4770552 DOI: 10.1186/s12864-016-2465-0] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 02/12/2016] [Indexed: 01/09/2023] Open
Abstract
Background Copper dependent nitrite reductase, NirK, catalyses the key step in denitrification, i.e. nitrite reduction to nitric oxide. Distinct structural NirK classes and phylogenetic clades of NirK-type denitrifiers have previously been observed based on a limited set of NirK sequences, however, their environmental distribution or ecological strategies are currently unknown. In addition, environmental nirK-type denitrifiers are currently underestimated in PCR-dependent surveys due to primer coverage limitations that can be attributed to their broad taxonomic diversity and enormous nirK sequence divergence. Therefore, we revisited reported analyses on partial NirK sequences using a taxonomically diverse, full-length NirK sequence dataset. Results Division of NirK sequences into two phylogenetically distinct clades was confirmed, with Clade I mainly comprising Alphaproteobacteria (plus some Gamma- and Betaproteobacteria) and Clade II harbouring more diverse taxonomic groups like Archaea, Bacteroidetes, Chloroflexi, Gemmatimonadetes, Nitrospirae, Firmicutes, Actinobacteria, Planctomycetes and Proteobacteria (mainly Beta and Gamma). Failure of currently available primer sets to target diverse NirK-type denitrifiers in environmental surveys could be attributed to mismatches over the whole length of the primer binding regions including the 3′ site, with Clade II sequences containing higher sequence divergence than Clade I sequences. Simultaneous presence of both the denitrification and DNRA pathway could be observed in 67 % of all NirK-type denitrifiers. Conclusion The previously reported division of NirK into two distinct phylogenetic clades was confirmed using a taxonomically diverse set of full-length NirK sequences. Enormous sequence divergence of nirK gene sequences, probably due to variable nirK evolutionary trajectories, will remain an issue for covering diverse NirK-type denitrifiers in amplicon-based environmental surveys. The potential of a single organism to partition nitrate to either denitrification or dissimilatory nitrate reduction to ammonium appeared to be more widespread than originally anticipated as more than half of all NirK-type denitrifiers were shown to contain both pathways in their genome. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-2465-0) contains supplementary material, which is available to authorized users.
Collapse
|
14
|
Graham EB, Knelman JE, Schindlbacher A, Siciliano S, Breulmann M, Yannarell A, Beman JM, Abell G, Philippot L, Prosser J, Foulquier A, Yuste JC, Glanville HC, Jones DL, Angel R, Salminen J, Newton RJ, Bürgmann H, Ingram LJ, Hamer U, Siljanen HMP, Peltoniemi K, Potthast K, Bañeras L, Hartmann M, Banerjee S, Yu RQ, Nogaro G, Richter A, Koranda M, Castle SC, Goberna M, Song B, Chatterjee A, Nunes OC, Lopes AR, Cao Y, Kaisermann A, Hallin S, Strickland MS, Garcia-Pausas J, Barba J, Kang H, Isobe K, Papaspyrou S, Pastorelli R, Lagomarsino A, Lindström ES, Basiliko N, Nemergut DR. Microbes as Engines of Ecosystem Function: When Does Community Structure Enhance Predictions of Ecosystem Processes? Front Microbiol 2016; 7:214. [PMID: 26941732 PMCID: PMC4764795 DOI: 10.3389/fmicb.2016.00214] [Citation(s) in RCA: 255] [Impact Index Per Article: 31.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Accepted: 02/09/2016] [Indexed: 11/13/2022] Open
Abstract
Microorganisms are vital in mediating the earth's biogeochemical cycles; yet, despite our rapidly increasing ability to explore complex environmental microbial communities, the relationship between microbial community structure and ecosystem processes remains poorly understood. Here, we address a fundamental and unanswered question in microbial ecology: 'When do we need to understand microbial community structure to accurately predict function?' We present a statistical analysis investigating the value of environmental data and microbial community structure independently and in combination for explaining rates of carbon and nitrogen cycling processes within 82 global datasets. Environmental variables were the strongest predictors of process rates but left 44% of variation unexplained on average, suggesting the potential for microbial data to increase model accuracy. Although only 29% of our datasets were significantly improved by adding information on microbial community structure, we observed improvement in models of processes mediated by narrow phylogenetic guilds via functional gene data, and conversely, improvement in models of facultative microbial processes via community diversity metrics. Our results also suggest that microbial diversity can strengthen predictions of respiration rates beyond microbial biomass parameters, as 53% of models were improved by incorporating both sets of predictors compared to 35% by microbial biomass alone. Our analysis represents the first comprehensive analysis of research examining links between microbial community structure and ecosystem function. Taken together, our results indicate that a greater understanding of microbial communities informed by ecological principles may enhance our ability to predict ecosystem process rates relative to assessments based on environmental variables and microbial physiology.
Collapse
Affiliation(s)
- Emily B Graham
- Institute of Arctic and Alpine Research, University of Colorado Boulder, BoulderCO, USA; Biological Sciences Division, Pacific Northwest National Laboratory, RichlandWA, USA
| | - Joseph E Knelman
- Institute of Arctic and Alpine Research, University of Colorado Boulder, BoulderCO, USA; US Department of Energy, Joint Genome Institute, Walnut CreekCA, USA
| | - Andreas Schindlbacher
- Department of Forest Ecology, Federal Research and Training Centre for Forests, Bundesforschungs- und Ausbildungszentrum für Wald Vienna, Austria
| | - Steven Siciliano
- Department of Soil Science, University of Saskatchewan, Saskatoon SK, Canada
| | - Marc Breulmann
- Helmholtz Centre for Environmental Research - Centre for Environmental Biotechnology Leipzig, Germany
| | - Anthony Yannarell
- Department of Natural Resources and Environmental Sciences, University of Illinois at Urbana-Champaign, Urbana IL, USA
| | - J M Beman
- Life and Environmental Sciences and Sierra Nevada Research Institute, University of California - Merced, Merced CA, USA
| | - Guy Abell
- School of Medicine, Flinders University, Adelaide SA, Australia
| | - Laurent Philippot
- Institut National de la Recherche Agronomique - Agroecology Dijon, France
| | - James Prosser
- Institute of Biological and Environmental Sciences, University of Aberdeen Aberdeen, UK
| | - Arnaud Foulquier
- Irstea, UR MALY, Centre de Lyon-Villeurbanne Villeurbanne, France
| | - Jorge C Yuste
- Department of Biogeography and Global Change, Museo Nacional de Ciencias Naturales, Consejo Superior de Investigaciones Científicas Madrid, Spain
| | | | - Davey L Jones
- Environment Centre Wales, Bangor University Gwynedd, UK
| | - Roey Angel
- Department of Microbiology and Ecosystem Science, University of Vienna Vienna, Austria
| | - Janne Salminen
- Häme University of Applied Sciences Hämeenlinna, Finland
| | - Ryan J Newton
- School of Freshwater Sciences, University of Wisconsin-Milwaukee, Milwaukee WI, USA
| | - Helmut Bürgmann
- Department of Surface Waters, Eawag: Swiss Federal Institute of Aquatic Science and Technology Kastanienbaum, Switzerland
| | - Lachlan J Ingram
- Centre for Carbon, Water and Food, The University of Sydney, Sydney NSW, Australia
| | - Ute Hamer
- Institute of Landscape Ecology, University of Münster Münster, Germany
| | - Henri M P Siljanen
- Department of Environmental and Biological Sciences, University of Eastern Finland Kuopio, Finland
| | | | - Karin Potthast
- Institute of Soil Science and Site Ecology, Technische University Dresden, Germany
| | - Lluís Bañeras
- Institute of Aquatic Ecology, Facultat de Ciències, University of Girona Girona, Spain
| | - Martin Hartmann
- Institute for Sustainability Sciences - Agroscope Zurich, Switzerland
| | | | - Ri-Qing Yu
- Department of Biology, University of Texas at Tyler, Tyler TX, USA
| | - Geraldine Nogaro
- EDF R&D, National Hydraulics and Environmental Laboratory Chatou, France
| | - Andreas Richter
- Department of Microbiology and Ecosystem Science, University of Vienna Vienna, Austria
| | - Marianne Koranda
- Division of Terrestrial Ecosystem Research, Department of Microbiology and Ecosystem Science, University of Vienna Vienna, Austria
| | - Sarah C Castle
- Department of Ecosystem and Conservation Sciences, University of Montana, Missoula MT, USA
| | - Marta Goberna
- Centro de Investigación y Docencia Económicas - Consejo Superior de Investigaciones Científicas Valencia, Spain
| | - Bongkeun Song
- Department of Biological Science, Virginia Institute of Marine Science, Gloucester Point VA, USA
| | - Amitava Chatterjee
- AES School of Natural Resources Sciences, North Dakota State University, Fargo ND, USA
| | - Olga C Nunes
- LEPABE - Laboratory for Process Engineering, Environmental, Biotechnology and Energy, Faculdade de Engenharia da Universidade do Porto Porto, Portugal
| | - Ana R Lopes
- LEPABE - Laboratory for Process Engineering, Environmental, Biotechnology and Energy, Faculdade de Engenharia da Universidade do Porto Porto, Portugal
| | - Yiping Cao
- Southern California Coastal Water Research Project Authority, Costa Mesa CA, USA
| | - Aurore Kaisermann
- UMR, Interactions Sol Plante Atmosphère, INRA Bordeaux Villenave d'Ornon, France
| | - Sara Hallin
- Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences Uppsala, Sweden
| | - Michael S Strickland
- Department of Biological Sciences, Virginia Polytechnic Institute, State University, Blacksburg VA, USA
| | | | - Josep Barba
- Centre de Recerca Ecològica i Aplicacions Forestals, Cerdanyola del Vallès Barcelona, Spain
| | - Hojeong Kang
- School of Civil and Environmental Engineering, Yonsei University Seoul, South Korea
| | - Kazuo Isobe
- Department of Applied Biological Chemistry, The University of Tokyo Tokyo, Japan
| | - Sokratis Papaspyrou
- Department of Biomedicine, Biotechnology and Public Health, University of Cadiz Puerto Real, Spain
| | | | | | - Eva S Lindström
- Department of Ecology and Genetics/Limnology, Uppsala University Uppsala, Sweden
| | - Nathan Basiliko
- Vale Living with Lakes Centre and Department of Biology, Laurentian University, Sudbury ON, Canada
| | - Diana R Nemergut
- Institute of Arctic and Alpine Research, University of Colorado Boulder, BoulderCO, USA; Biology Department, Duke University, DurhamNC, USA
| |
Collapse
|
15
|
Brenzinger K, Dörsch P, Braker G. pH-driven shifts in overall and transcriptionally active denitrifiers control gaseous product stoichiometry in growth experiments with extracted bacteria from soil. Front Microbiol 2015; 6:961. [PMID: 26441895 PMCID: PMC4585170 DOI: 10.3389/fmicb.2015.00961] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Accepted: 08/31/2015] [Indexed: 01/27/2023] Open
Abstract
Soil pH is a strong regulator for activity as well as for size and composition of denitrifier communities. Low pH not only lowers overall denitrification rates but also influences denitrification kinetics and gaseous product stoichiometry. N2O reductase is particularly sensitive to low pH which seems to impair its activity post-transcriptionally, leading to higher net N2O production. Little is known about how complex soil denitrifier communities respond to pH change and whether their ability to maintain denitrification over a wider pH range relies on phenotypic redundancy. In the present study, we followed the abundance and composition of an overall and transcriptionally active denitrifier community extracted from a farmed organic soil in Sweden (pHH2O = 7.1) when exposed to pH 5.4 and drifting back to pH 6.6. The soil was previously shown to retain much of its functioning (low N2O/N2 ratios) over a wide pH range, suggesting a high functional versatility of the underlying community. We found that denitrifier community composition, abundance and transcription changed throughout incubation concomitant with pH change in the medium, allowing for complete reduction of nitrate to N2 with little accumulation of intermediates. When exposed to pH 5.4, the denitrifier community was able to grow but reduced N2O to N2 only when near-neutral pH was reestablished by the alkalizing metabolic activity of an acid-tolerant part of the community. The genotypes proliferating under these conditions differed from those dominant in the control experiment run at neutral pH. Denitrifiers of the nirS-type appeared to be severely suppressed by low pH and nirK-type and nosZ-containing denitrifiers showed strongly reduced transcriptional activity and growth, even after restoration of neutral pH. Our study suggests that low pH episodes alter transcriptionally active populations which shape denitrifier communities and determine their gas kinetics.
Collapse
Affiliation(s)
- Kristof Brenzinger
- Department of Biogeochemistry, Max Planck Institute for Terrestrial Microbiology Marburg, Germany
| | - Peter Dörsch
- Department of Environmental Sciences, Norwegian University of Life Sciences Ås, Norway
| | - Gesche Braker
- Department of Biogeochemistry, Max Planck Institute for Terrestrial Microbiology Marburg, Germany ; University of Kiel Kiel, Germany
| |
Collapse
|
16
|
Saarenheimo J, Tiirola MA, Rissanen AJ. Functional gene pyrosequencing reveals core proteobacterial denitrifiers in boreal lakes. Front Microbiol 2015; 6:674. [PMID: 26191058 PMCID: PMC4486872 DOI: 10.3389/fmicb.2015.00674] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Accepted: 06/19/2015] [Indexed: 11/13/2022] Open
Abstract
Denitrification is an important microbial process in aquatic ecosystems that can reduce the effects of eutrophication. Here, quantification and pyrosequencing of nirS, nirK, and nosZ genes encoding for nitrite and nitrous oxide reductases was performed in sediment samples from four boreal lakes to determine the structure and seasonal stability of denitrifying microbial populations. Sediment quality and nitrate concentrations were linked to the quantity and diversity of denitrification genes, the abundance of denitrifying populations (nirS and nosZ genes) correlated with coupled nitrification-denitrification (Dn), and the denitrification of the overlying water NO3- (Dw) correlated with the nirS/nirK ratio. The number of core nirS, nirK, and nosZ operational taxonomical units (OTUs) was low (6, 7, and 3, respectively), and most of these core OTUs were shared among the lakes. Dominant nirK sequences matched best with those of the order Rhizobiales, which was one of the main bacterial orders present in the sediment microbiomes, whereas the dominant nirS sequences were affiliated with the order Burkholderiales. Over half of the nosZ sequences belonged to a single OTU of the order Burkholderiales, but coupled nitrification–denitrification rate correlated with another dominant nosZ OTU assigned to the order Rhodospirillales. The study indicates that a few core proteobacterial clusters may drive denitrification in boreal lake sediments, as the same Alpha- and Betaproteobacteria denitrifier clusters were present in different lakes and seasons.
Collapse
Affiliation(s)
- Jatta Saarenheimo
- Department of Biological and Environmental Science, University of Jyväskylä Jyväskylä, Finland
| | - Marja Annika Tiirola
- Department of Biological and Environmental Science, University of Jyväskylä Jyväskylä, Finland
| | - Antti J Rissanen
- Department of Biological and Environmental Science, University of Jyväskylä Jyväskylä, Finland
| |
Collapse
|