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Li H, Sun R, Zhang X, Lin H, Xie Y, Han Y, Pan Y, Wang D, Dong K. Characteristics of denitrification and microbial community in respect to various H 2 pressures and distances to the gas supply end in H 2-based MBfR. Front Microbiol 2022; 13:1023402. [PMID: 36212855 PMCID: PMC9542790 DOI: 10.3389/fmicb.2022.1023402] [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: 08/19/2022] [Accepted: 09/07/2022] [Indexed: 11/30/2022] Open
Abstract
The hydrogen-based hollow fiber membrane biofilm reactor (H2-based MBfR) has shown to be a promising technology for nitrate (NO3 --N) reduction. Hollow fiber membranes (HFM) operating in a closed mode in an H2-based MBfR often suffer from reverse gas diffusion, taking up space for the effective gas substrate and resulting in a reduction in the HFM diffusion efficiency, which in turn affects denitrification performance. In this work, we developed a laboratory-scale H2-based MBfR, which operated in a closed mode to investigate the dynamics of denitrification performance and biofilm microbial community analysis at different H2 supply pressures. A faster formation of biofilm on the HFM and a shorter start-up period were found for a higher H2 supply pressure. An increase in the H2 pressure under 0.08 MPa could significantly promote denitrification, while a minor increase in denitrification was observed once the H2 pressure was over 0.08 MPa. Sequencing analysis of the biofilm concluded that (i) the dominant phylum-level bacteria in the reactor during the regulated hydrogen pressure phase were Gammaproteobacteria and Alphaproteobacteria; (ii) when the hydrogen pressure was 0.04-0.06 MPa, the dominant bacteria in the MBfR were mainly enriched on the hollow fiber membrane near the upper location (Gas inlet). With a gradual increase in the hydrogen pressure, the enrichment area of the dominant bacteria in MBfR gradually changed from the upper location to the distal end of the inlet. When the hydrogen pressure was 0.10 MPa, the dominant bacteria were mainly enriched on the hollow fiber membrane in the down location of the MBfR.
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Affiliation(s)
| | | | | | | | | | | | | | - Dunqiu Wang
- College of Environmental Science and Engineering, Guilin University of Technology, Guilin, China
| | - Kun Dong
- College of Environmental Science and Engineering, Guilin University of Technology, Guilin, China
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Srivastava M, Kaushik MS, Singh A, Singh D, Mishra AK. Molecular phylogeny of heterotrophic nitrifiers and aerobic denitrifiers and their potential role in ammonium removal. J Basic Microbiol 2016; 56:907-21. [PMID: 27037833 DOI: 10.1002/jobm.201500689] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 03/09/2016] [Indexed: 11/06/2022]
Abstract
To investigate the physiology and taxonomic composition of the key players of nitrification and denitrification processes in paddy fields, culture dependent and independent studies have been carried out. A total of 28 bacterial strains have been screened in which six were capable of reducing nitrate and nitrite as well as having significant ammonium removal potential. 16S rRNA-PCR-DGGE-based molecular typing of enriched batch culture was done with time duration to explore and identify dominant and stable soil denitrifiers. Notably, three isolates namely PDN3, PDN19, PDN14 were found to be efficiently involved in the removal of 70.32, 71.46, and 81.50% of NH4 (+) and showed closest similarity (>98%) with Bacillus cereus, Bacillus subtilis, and Pseudomonas aeruginosa strains, respectively. The bacterial strain PDN14 showed maximum growth with highest ammonium removal rate (2.78 gN/(m(3) ·h) has also been characterized based on nosZ gene which showed similarity to uncultured γ- Proteobacteria, P. aeruginosa sp. B3. Median joining (MJ) network and rRNA secondary structure have been analyzed for their detailed taxonomic diversity and derived haplotype-based co-occurrence. Results demonstrated that such strains can serve as good candidate for in situ nitrogen transformation in paddy soils and improvingly characterized by physiological and detailed phylogenetic approaches.
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Affiliation(s)
- Meenakshi Srivastava
- Laboratory of Microbial Genetics, Department of Botany, Banaras Hindu University, Varanasi, India
| | - Manish Singh Kaushik
- Laboratory of Microbial Genetics, Department of Botany, Banaras Hindu University, Varanasi, India
| | - Anumeha Singh
- Laboratory of Microbial Genetics, Department of Botany, Banaras Hindu University, Varanasi, India
| | - Deepti Singh
- Laboratory of Microbial Genetics, Department of Botany, Banaras Hindu University, Varanasi, India
| | - Arun Kumar Mishra
- Laboratory of Microbial Genetics, Department of Botany, Banaras Hindu University, Varanasi, India
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Math RK, Jin HM, Jeong SH, Jeon CO. Defluviimonas aestuarii sp. nov., a marine bacterium isolated from a tidal flat, and emended description of the genus Defluviimonas Foesel et al. 2011. Int J Syst Evol Microbiol 2013; 63:2895-2900. [PMID: 23334880 DOI: 10.1099/ijs.0.048389-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A novel Gram-staining-negative, strictly aerobic bacterium, designated BS14(T), was isolated from a marine tidal flat of the South Sea in Korea. Colonies were opaque, white, smooth and circular on marine agar. Cells were moderately halophilic, non-motile rods showing catalase- and oxidase-positive reactions. Growth of strain BS14(T) was observed at 5-40 °C (optimum: 30 °C), pH 6.5-9.5 (optimum: 7.0-7.5) and 0-10 % (w/v) NaCl (optimum: 1-1.5 %). The G+C content of the genomic DNA was 61.6 mol%. Strain BS14(T) contained ubiquinone-10 (Q-10) as the sole respiratory quinone and summed feature 8 (comprising C18 : 1ω7c and/or C18 : 1ω6c), C18 : 0 3-OH, C10 : 0 3-OH and C18 : 0 as the major fatty acids. The polar lipid pattern comprised phosphatidylethanolamine, diphosphatidylglycerol, an unidentified aminolipid, an unidentified phospholipid and an unidentified polar lipid. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain BS14(T) formed a tight phylogenetic lineage with Defluviimonas denitrificans D9-3(T) with a bootstrap value of 100 %. The 16S rRNA gene sequence similarity between strain BS14(T) and D. denitrificans D9-3(T) was 97.4 % and their DNA-DNA relatedness was 19.1 ± 3.6 %. Based on the phenotypic and genotypic studies, strain BS14(T) represents a novel species of the genus Defluviimonas, for which the name Defluviimonas aestuarii sp. nov. is proposed. The type strain is BS14(T) (= KACC 16442(T) = JCM 18630(T)). An emended description of the genus Defluviimonas Foesel et al. 2011 is also proposed.
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Affiliation(s)
- Renukaradhya K Math
- Department of Life Science & Research Center for Biomolecules and Biosystems, Chung-Ang University, Seoul 156-756, Republic of Korea
| | - Hyun Mi Jin
- Department of Life Science & Research Center for Biomolecules and Biosystems, Chung-Ang University, Seoul 156-756, Republic of Korea
| | - Sang Hyeon Jeong
- Department of Life Science & Research Center for Biomolecules and Biosystems, Chung-Ang University, Seoul 156-756, Republic of Korea
| | - Che Ok Jeon
- Department of Life Science & Research Center for Biomolecules and Biosystems, Chung-Ang University, Seoul 156-756, Republic of Korea
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VandeVoort AR, Arai Y. Effect of Silver Nanoparticles on Soil Denitrification Kinetics. Ind Biotechnol (New Rochelle N Y) 2012. [DOI: 10.1089/ind.2012.0026] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
| | - Yuji Arai
- School of Agricultural, Forest and Environmental Sciences, Clemson University, Clemson, SC
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Verbaendert I, Boon N, De Vos P, Heylen K. Denitrification is a common feature among members of the genus Bacillus. Syst Appl Microbiol 2011; 34:385-91. [PMID: 21530125 DOI: 10.1016/j.syapm.2011.02.003] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2010] [Revised: 02/04/2011] [Accepted: 02/04/2011] [Indexed: 11/26/2022]
Abstract
Although several Gram-positive denitrifiers have been characterized in the past, there is still uncertainty about the occurrence of the denitrification trait among these bacteria. In an isolation campaign on luvisol soil, Bacillus spp. were among the most abundant retrieved cultured denitrifiers next to members of Rhizobiaceae family and genus Cupriavidus. Subsequent screening of 180 representatives of the genus Bacillus (encompassing more than half of the current validly described species diversity in Bacillus) was performed and demonstrated the potential for dissimilatory reduction of nitrogen compounds in 45 of the 87 investigated species, with 19 species containing denitrifying members. The influence of several electron donors and acceptors was tested. The use of more than one electron acceptor, e.g. both nitrate and nitrite, was crucial to detect the denitrification potential of reference strains. Complex electron donors, most suitable for aerobic growth, were ideal for denitrification testing, while retrieval of denitrifiers from the environment was facilitated by the use of defined electron donors, due to less interference of other anaerobic growers. The outcome of the isolation campaign and screening of reference strain set suggest that bacilli may be potential contributors to denitrification in terrestrial and possibly other ecosystems.
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Affiliation(s)
- Ines Verbaendert
- Laboratory of Microbiology, Department of Biochemistry and Microbiology, Ghent University, K.L. Ledeganckstraat 35, B-9000 Gent, Belgium
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Abstract
Denitrifying organisms are essential in removing fixed nitrogen pollutants from ecosystems (e.g. sewage sludge). They can be detrimental (e.g. for agricultural soil) and can also produce the greenhouse gas N2O (nitrous oxide). Therefore a more comprehensive understanding of this process has become increasingly important regarding its global environmental impact. Even though bacterial genome sequencing projects may reveal new data, to date the denitrification abilities and features in Gram-positive bacteria are still poorly studied and understood. The present review evaluates current knowledge on the denitrification trait in Gram-positive bacteria and addresses the likely existence of unknown denitrification genes. In addition, current molecular tools to study denitrification gene diversity in pure cultures and environmental samples seem to be highly biased, and additional novel approaches for the detection of denitrifying (Gram-positive) bacteria appear to be crucial in re-assessing the real diversity of denitrifiers.
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Characterization of heterotrophic nitrifying bacteria with respiratory ammonification and denitrification activity – Description of Paenibacillus uliginis sp. nov., an inhabitant of fen peat soil and Paenibacillus purispatii sp. nov., isolated from a spacecraft assembly clean room. Syst Appl Microbiol 2010; 33:328-36. [DOI: 10.1016/j.syapm.2010.07.004] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2010] [Revised: 07/05/2010] [Accepted: 07/07/2010] [Indexed: 11/23/2022]
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Theerachat M, Virunanon C, Chulalaksananukul S, Sinbuathong N, Chulalaksananukul W. NirK and nirS Nitrite reductase genes from non-agricultural forest soil bacteria in Thailand. World J Microbiol Biotechnol 2010; 27:999-1003. [PMID: 21475726 PMCID: PMC3056131 DOI: 10.1007/s11274-010-0521-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2010] [Accepted: 07/28/2010] [Indexed: 11/06/2022]
Abstract
The genetic heterogeneity of the nitrite reductase gene (nirK and nirS) fragments from denitrifying prokaryotes in a non-agricultural forest soil in Thailand was investigated using soil samples from the Plant Germplasm-Royal Initiation Project area in Kanchanaburi Province, Thailand. Soil bacteria were screened for denitrification activity and 13 (from 211) positive isolates were obtained and further evaluated for their ability to reduce nitrate and to accumulate or reduce nitrite. Three species with potentially previously unreported denitrifying activities were recorded. Analysis of the partial nirK and nirS sequences of these 13 strains revealed a diverse sequence heterogeneity in these two genes within the same environment and even potentially within the same host species, the potential existence of lateral gene transfer and the first record of both nirK and nirS homologues in one bacterial species. Finally, isolates of two species of bacteria (Corynebacterium propinquum and Micrococcus lylae) are recorded as denitrifiers for the first time.
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Affiliation(s)
- Monnat Theerachat
- Department of Botany, Faculty of Science, Chulalongkorn University, Bangkok, 10330 Thailand
| | - Chompunuch Virunanon
- Department of Botany, Faculty of Science, Chulalongkorn University, Bangkok, 10330 Thailand
| | - Suphang Chulalaksananukul
- Department of Chemical Engineering, Faculty of Engineering, Mahidol University, Salaya Campus, Nakornpathom, 73170 Thailand
| | - Nusara Sinbuathong
- Scientific Equipment Center, Kasetsart University Research and Development Institute, Kasetsart University, Bangkok, 10900 Thailand
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The community composition of soil-denitrifying bacteria from a turfgrass environment. Res Microbiol 2010; 161:315-25. [DOI: 10.1016/j.resmic.2010.03.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2009] [Revised: 03/30/2010] [Accepted: 03/31/2010] [Indexed: 11/22/2022]
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Ashida N, Ishii S, Hayano S, Tago K, Tsuji T, Yoshimura Y, Otsuka S, Senoo K. Isolation of functional single cells from environments using a micromanipulator: application to study denitrifying bacteria. Appl Microbiol Biotechnol 2009; 85:1211-7. [PMID: 19936739 DOI: 10.1007/s00253-009-2330-z] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2009] [Revised: 10/07/2009] [Accepted: 10/24/2009] [Indexed: 11/24/2022]
Abstract
We developed a novel method to isolate functionally active single cells from environmental samples and named it the functional single-cell (FSC) isolation method. This method is based on a combination of substrate-responsive direct viable counts, live-cell staining with 5-carboxyfluorescein diacetate acetoxymethyl ester, and micromanipulation followed by cultivation in a medium. To evaluate this method, we applied it to study a denitrifying community in rice paddy soil. Similar denitrifier counts were obtained by the conventional most probable number analysis and our FSC isolation method. Using the FSC isolation method, 37 denitrifying bacteria were isolated, some of which harbored copper-containing nitrite reductase gene (nirK). The 16S rRNA gene analysis showed that members belonging to the genera Azospirillum and Ochrobactrum may be the major denitrifiers in the rice paddy soil. These results indicate that the FSC isolation method is a useful tool to obtain functionally active single cells from environmental samples.
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Affiliation(s)
- Naoaki Ashida
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
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11
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Yu L, Liu Y, Wang G. Identification of novel denitrifying bacteria Stenotrophomonas sp. ZZ15 and Oceanimonas sp. YC13 and application for removal of nitrate from industrial wastewater. Biodegradation 2008; 20:391-400. [PMID: 19002594 DOI: 10.1007/s10532-008-9230-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2008] [Accepted: 10/27/2008] [Indexed: 10/21/2022]
Abstract
Two novel denitrifying bacteria were successfully isolated from industrial wastewater and soil samples. Using morphological, biochemical/biophysical and 16S rRNA gene analyses, these two bacteria were identified as Stenotrophomonas sp. ZZ15 and Oceanimonas sp. YC13, respectively. Both of these two bacteria showed efficient NO(3) (-)-N removing abilities under a semi-anaerobic condition without obvious accumulation of NO(2) (-)-N, N(2)O-N and NH(4) (+)-N. NO(3) (-)-N removal from paper mill wastewater was also successful by treatments with either a denitrifier or an immobilization method. Therefore, this study provides valuable denitrifying bacteria in biotreatment of industrial wastewater and other environmental pollution caused by NO(3) (-)/NO(2) (-).
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Affiliation(s)
- Lu Yu
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
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Saito T, Ishii S, Otsuka S, Nishiyama M, Senoo K. Identification of Novel Betaproteobacteria in a Succinate-Assimilating Population in Denitrifying Rice Paddy Soil by Using Stable Isotope Probing. Microbes Environ 2008; 23:192-200. [DOI: 10.1264/jsme2.23.192] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Takayuki Saito
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo
| | - Satoshi Ishii
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo
| | - Shigeto Otsuka
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo
| | | | - Keishi Senoo
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo
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13
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Siragusa AJ, Swenson JE, Casamatta DA. Culturable bacteria present in the fluid of the hooded-pitcher plant Sarracenia minor based on 16S rDNA gene sequence data. MICROBIAL ECOLOGY 2007; 54:324-31. [PMID: 17380356 DOI: 10.1007/s00248-006-9205-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2006] [Revised: 12/22/2006] [Accepted: 12/27/2006] [Indexed: 05/14/2023]
Abstract
The culturable microbial community within the pitcher fluid of 93 Sarracenia minor carnivorous plants was examined over a 2-year study. Many aspects of the plant/bacterial/insect interaction within the pitcher fluid are minimally understood because the bacterial taxa present in these pitchers have not been identified. Thirteen isolates were characterized by 16S rDNA sequencing and subsequent phylogenetic analysis. The Proteobacteria were the most abundant taxa and included representatives from Serratia, Achromobacter, and Pantoea. The Actinobacteria Micrococcus was also abundant while Bacillus, Lactococcus, Chryseobacterium, and Rhodococcus were infrequently encountered. Several isolates conformed to species identifiers (>98% rDNA gene sequence similarity) including Serratia marcescens (isolates found in 27.5% of pitchers), Achromobacter xylosoxidans (37.6%), Micrococcus luteus (40.9%), Bacillus cereus (isolates found in 10.2%), Bacillus thuringiensis (5.4%), Lactococcus lactis (17.2%), and Rhodococcus equi (2.2%). Species-area curves suggest that sampling efforts were sufficient to recover a representative culturable bacterial community. The bacteria present represent a diverse community probably as a result of introduction by insect vectors, but the ecological significance remains under explored.
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Affiliation(s)
- Alex J Siragusa
- Department of Biology, University of North Florida, Jacksonville, FL 32224, USA
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Kandeler E, Deiglmayr K, Tscherko D, Bru D, Philippot L. Abundance of narG, nirS, nirK, and nosZ genes of denitrifying bacteria during primary successions of a glacier foreland. Appl Environ Microbiol 2006; 72:5957-62. [PMID: 16957216 PMCID: PMC1563666 DOI: 10.1128/aem.00439-06] [Citation(s) in RCA: 288] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Quantitative PCR of denitrification genes encoding the nitrate, nitrite, and nitrous oxide reductases was used to study denitrifiers across a glacier foreland. Environmental samples collected at different distances from a receding glacier contained amounts of 16S rRNA target molecules ranging from 4.9 x 10(5) to 8.9 x 10(5) copies per nanogram of DNA but smaller amounts of narG, nirK, and nosZ target molecules. Thus, numbers of narG, nirK, nirS, and nosZ copies per nanogram of DNA ranged from 2.1 x 10(3) to 2.6 x 10(4), 7.4 x 10(2) to 1.4 x 10(3), 2.5 x 10(2) to 6.4 x 10(3), and 1.2 x 10(3) to 5.5 x 10(3), respectively. The densities of 16S rRNA genes per gram of soil increased with progressing soil development. The densities as well as relative abundances of different denitrification genes provide evidence that different denitrifier communities develop under primary succession: higher percentages of narG and nirS versus 16S rRNA genes were observed in the early stage of primary succession, while the percentages of nirK and nosZ genes showed no significant increase or decrease with soil age. Statistical analyses revealed that the amount of organic substances was the most important factor in the abundance of eubacteria as well as of nirK and nosZ communities, and copy numbers of these two genes were the most important drivers changing the denitrifying community along the chronosequence. This study yields an initial insight into the ecology of bacteria carrying genes for the denitrification pathway in a newly developing alpine environment.
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Affiliation(s)
- Ellen Kandeler
- Institute of Soil Science, University of Hohenheim, D-70593 Stuttgart, Germany.
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Dandie CE, Burton DL, Zebarth BJ, Trevors JT, Goyer C. Analysis of denitrification genes and comparison of nosZ, cnorB and 16S rDNA from culturable denitrifying bacteria in potato cropping systems. Syst Appl Microbiol 2006; 30:128-38. [PMID: 16793234 DOI: 10.1016/j.syapm.2006.05.002] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2006] [Indexed: 11/24/2022]
Abstract
Bacterial denitrification in agricultural soils is a major source of nitrous oxide, a potent greenhouse gas. This study examined the culturable bacterial population of denitrifiers in arable field soils in potato (Solanum tuberosum L.) production and denitrification genes (nir, nor and nos) and 16S rDNA in those isolates. Enrichments for culturable denitrifiers yielded 31 diverse isolates that were then analysed for denitrification genes. The nitrous oxide reductase (nosZ) gene was found in all isolates. The majority of isolates ( approximately 90%) contained the cnorB nitric oxide reductase gene, with the remainder containing the qnorB gene. Nitrite reductase genes (nirS and nirK) were amplifiable from most of the isolates, and were segregated between species similar to previously isolated denitrifiers. Isolated strains were preliminarily identified using fatty acid methyl ester analysis and further identified using 16S rDNA sequencing. The majority of isolates (21) were classified as Pseudomonas sp., with smaller groups of isolates being most similar to Bosea spp. (4), Achromobacter spp. (4) and two isolates closely related to Sinorhizobium/Ensifer spp. Phylogenetic trees were compared among nosZ, cnorB and 16S rDNA genes for a subset of Pseudomonas strains. The trees were mostly congruent, but some Pseudomonas sp. isolates grouped differently depending on the gene analysed, indicating potential horizontal gene transfer of denitrification genes. Although Bosea spp. are known denitrifiers, to the best of our knowledge this is the first report of isolation and sequencing of denitrification genes from this bacterial genus.
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Affiliation(s)
- C E Dandie
- Potato Research Centre, Agriculture and Agri-Food Canada, Fredericton, NB, Canada E3B 4Z7
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