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John A. Fuerst - One of the best experts on this subject based on the ideXlab platform.
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Correspondence
2015Co-Authors: Margaret K Butler, John A. FuerstAbstract:The planctomycetes, order Planctomycetales, are a distinct phylum of domain Bacteria. Genes encoding the RNA portion of ribonuclease P (RNase P) of some planctomycete members were sequenced and compared with existing database planctomycete sequences. rnpB gene sequences encoding RNase P RNA were generated by a conserved primer PCR strategy for Planctomyces brasiliensis, Planctomyces limnophilus, Pirellula marina, Pirellula staleyi strain ATCC 35122, Isosphaera pallida, one other Isosphaera strain, Gemmata obscuriglobus and three other strains of the Gemmata group. These sequences were aligned against reference bacterial sequences and secondary structures of corresponding RNase P RNAs deduced by a comparative approach. P12 helices were found to be highly variable in length, as were helices P16.1 and P19, when present. RNase P RNA secondary structures of Gemmata isolates were found to have unusual features relative to other planctomycetes, including a long P9 helix and an insert in the P13 helix not found in any other member of domain Bacteria. These unique features are consistent with other unusual properties of this genus, distinguishing it from other bacteria. Phylogenetic analyses indicate that relationships between planctomycetes derived from RNase P RNA are consistent with 16S rRNA-based analyses
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Comparative analysis of ribonuclease P RNA of the planctomycetes.
International journal of systematic and evolutionary microbiology, 2004Co-Authors: Margaret K Butler, John A. FuerstAbstract:The planctomycetes, order Planctomycetales, are a distinct phylum of domain Bacteria. Genes encoding the RNA portion of ribonuclease P (RNase P) of some planctomycete members were sequenced and compared with existing database planctomycete sequences. rnpB gene sequences encoding RNase P RNA were generated by a conserved primer PCR strategy for Planctomyces brasiliensis, Planctomyces limnophilus, Pirellula marina, Pirellula staleyi strain ATCC 35122, Isosphaera pallida, one other Isosphaera strain, Gemmata obscuriglobus and three other strains of the Gemmata group. These sequences were aligned against reference bacterial sequences and secondary structures of corresponding RNase P RNAs deduced by a comparative approach. P12 helices were found to be highly variable in length, as were helices P16.1 and P19, when present. RNase P RNA secondary structures of Gemmata isolates were found to have unusual features relative to other planctomycetes, including a long P9 helix and an insert in the P13 helix not found in any other member of domain Bacteria. These unique features are consistent with other unusual properties of this genus, distinguishing it from other bacteria. Phylogenetic analyses indicate that relationships between planctomycetes derived from RNase P RNA are consistent with 16S rRNA-based analyses.
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Molecular and ultrastructural confirmation of classification of ATCC 35122 as a strain of Pirellula staleyi.
International Journal of Systematic and Evolutionary Microbiology, 2002Co-Authors: Margaret K Butler, Richard I Webb, Jenny Wang, John A. FuerstAbstract:A freshwater isolate from Campus Lake, Baton Rouge, LA, USA, strain ATCC 35122 (= ICPB 4362 = Schmidt CLPM White = Tekniepe BT2 white), which had been proposed as a putative reference strain for 'Planctomyces staleyi' (later reclassified as Pirellula staleyi), has been re-examined to establish its relationship to the type strain of Pirellula staleyi, ATCC 27377T. 165 rRNA sequencing confirms its very close relationship to ATCC 27377T and its membership of the order Planctomycetales. Ultrastructural characteristics are also consistent with its membership of the planctomycetes and of the genus Pirellula. These characteristics include polar crateriform structures and the occurrence of the unique internal, single-membrane-bounded compartment enclosing the nucleoid and ribosome-like particles, the pirellulosome, and a polar cap region. Cells of strain ATCC 35122 often displayed pointed, hump-like protrusions opposite each other on the cell, constituting prosthecae, and these were also found to be present on cells of strain ATCC 27377T. The original identification of ATCC 35122 as a strain of Pirellula staleyi is confirmed on both molecular and phenotypic grounds.
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Cell compartmentalisation in planctomycetes: novel types of structural organisation for the bacterial cell.
Archives of Microbiology, 2001Co-Authors: Margaret R. Lindsay, Richard I Webb, Margaret K Butler, Rebecca J. Forde, Marc Strous, Mike S. M. Jetten, John A. FuerstAbstract:The organisation of cells of the planctomycete species Pirellula marina, Isosphaera pallida, Gemmata obscuriglobus, Planctomyces maris and "Candidatus Brocadia anammoxidans" was investigated based on ultrastructure derived from thin-sections of cryosubstituted cells, freeze-fracture replicas, and in the case of Gemmata obscuriglobus and Pirellula marina, computer-aided 3-D reconstructions from serial sections of cryosubstituted cells. All planctomycete cells display a peripheral ribosome-free region, termed here the paryphoplasm, surrounding the perimeter of the cell, and an interior region including any nucleoid regions as well as ribosome-like particles, bounded by a single intracytoplasmic membrane (ICM), and termed the pirellulosome in Pirellula species. Immunogold labelling and RNase-gold cytochemistry indicates that in planctomycetes all the cell DNA is contained wholly within the interior region bounded by the ICM, and the paryphoplasm contains no DNA but at least some of the cell's RNA. The ICM in Isosphaera pallida and Planctomyces maris is invaginated such that the paryphoplasm forms a major portion of the cell interior in sections, but in other planctomycetes it remains as a peripheral zone. In the anaerobic ammonium-oxidising ("anammox" process) chemoautotroph "Candidatus Brocadia anammoxidans" the interior region bounded by ICM contains a further internal single-membrane-bounded region, the anammoxosome. In Gemmata obscuriglobus, the interior ICM-bounded region contains the nuclear body, a double-membrane-bounded region containing the cell's nucleoid and all genomic DNA in addition to some RNA. Shared features of cell compartmentalisation in different planctomycetes are consistent with the monophyletic nature of the planctomycetes as a distinct division of the Bacteria. The shared organisational plan for the planctomycete cell constitutes a new type not known in cells of other bacteria.
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Isolation and molecular identification of planctomycete bacteria from postlarvae of the giant tiger prawn, Penaeus monodon.
Applied and environmental microbiology, 1997Co-Authors: John A. Fuerst, Margaret R. Lindsay, H G Gwilliam, A Lichanska, C Belcher, J E Vickers, Philip HugenholtzAbstract:Bacteria phenotypically resembling members of the phylogenetically distinct planctomycete group of the domain Bacteria were isolated from postlarvae of the giant tiger prawn, Penaeus monodon. A selective medium designed in the light of planctomycete antibiotic resistance characteristics was used for this isolation. Planctomycetes were isolated from both healthy and monodon baculovirus-infected prawn postlarvae. The predominant colony type recovered from postlarvae regardless of viral infection status was nonpigmented. Other, less commonly observed types were pink or orange pigmented. A planctomycete-specific 16S rRNA-directed probe was designed and used to screen the isolates for their identity as planctomycetes prior to molecular phylogenetic characterization. 16S rRNA genes from nine prawn isolates together with two planctomycete reference strains (Planctomyces brasiliensis and Gemmata obscuriglobus) were sequenced and compared with reference sequences from the planctomycetes and other members of the domain Bacteria. Phylogenetic analyses and sequence signatures of the 16S rRNA genes demonstrated that the prawn isolates were members of the planctomycete group. Five representatives of the predominant nonpigmented colony type were members of the Pirellula group within the planctomycetes, as were three pink-pigmented colony type representatives. Homology values and tree topology indicated that representatives of the nonpigmented and pink-pigmented colony types formed two discrete clusters within the Pirellula group, not identical to any known Pirellula species. A sole representative of the orange colony type was a member of the Planctomyces group, virtually identical in 16S rDNA sequence to P. brasiliensis, and exhibited distinctive morphology.
Svetlana N Dedysh - One of the best experts on this subject based on the ideXlab platform.
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Planctomicrobium piriforme gen. nov., sp. nov., a stalked planctomycete from a littoral wetland of a boreal lake.
International Journal of Systematic and Evolutionary Microbiology, 2015Co-Authors: Irina S Kulichevskaya, Jaap Sinninghe S Damste, Anastasia A. Ivanova, Ekaterina N. Detkova, W. Irene C. Rijpstra, Svetlana N DedyshAbstract:An aerobic, budding, non-pigmented and rosette-forming bacterium was isolated from a littoral wetland of a boreal lake located in Valaam Island, northern Russia, and designated strain P3T. Ellipsoidal to pear-shaped cells of this bacterium were covered with crateriform pits and possessed stalks suggesting a planctomycete morphotype. 16S rRNA gene sequence analysis confirmed that strain P3T was a member of the order Planctomycetales and belonged to a phylogenetic lineage defined by the genus Planctomyces , with 89 and 86 % sequence similarity to Planctomyces brasiliensis and Planctomyces maris , respectively. Strain P3T was a mildly acidophilic, mesophilic organism capable of growth at pH values between pH 4.2 and 7.1 (with an optimum at pH 6.0–6.5) and at temperatures between 10 and 30 °C (optimum at 20–28 °C). Most sugars, a number of polysaccharides and several organic acids were the preferred growth substrates. Compared with Planctomyces brasiliensis and Planctomyces maris , which require NaCl for growth, strain P3T was salt-sensitive and did not develop at NaCl concentrations above 0.5 % (w/v). The major fatty acids were C16 : 0 and C16 : 1ω7c; the cells also contained significant amounts of C18 : 1ω7c and C18 : 0. The major intact polar lipids were diacylglycerol-O-(N,N,N-trimethyl)homoserine (DGTS) lipids; the major neutral lipids were long-chain 1,(ω-1)-diols and C31 : 9 hydrocarbon. The quinone was MK-6, and the G+C content of the DNA was 59.0 mol%. Strain P3T differed from Planctomyces brasiliensis and Planctomyces maris by cell morphology, substrate utilization pattern and a number of physiological characteristics. Based on these data, the novel isolate should be considered as representing a novel genus and species of planctomycetes, for which the name Planctomicrobium piriforme gen. nov., sp. nov., is proposed. The type strain is P3T ( = DSM 26348T = VKM B-2887T).
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schlesneria paludicola gen nov sp nov the first acidophilic member of the order planctomycetales from sphagnum dominated boreal wetlands
International Journal of Systematic and Evolutionary Microbiology, 2007Co-Authors: Irina S Kulichevskaya, Anastasia O. Ivanova, Olga Baulina, Paul L. E. Bodelier, Svetlana E. Belova, Irene W C Rijpstra, Jaap Sinninghe S Damste, G A Zavarzin, Svetlana N DedyshAbstract:Three strains of budding, ellipsoid-shaped and rosette-forming bacteria were isolated from acidic Sphagnum-dominated boreal wetlands of northern Russia and were designated strains MPL7T, MOB77 and SB2. The presence of crateriform pits and numerous fibrillar appendages on the cell surface and an unusual spur-like projection on one pole of the cell indicated a planctomycete morphotype. These isolates are moderately acidophilic, mesophilic organisms capable of growth at pH values between 4.2 and 7.5 (with an optimum at pH 5.0–6.2) and at temperatures between 4 and 32 °C (optimum 15–26 °C). The major fatty acids are C16 : 0 and C16 : 1 ω7c; the major quinone is MK-6. The G+C content of the DNA is 54.4–56.5 mol%. Strains MPL7T, MOB77 and SB2 possess nearly identical 16S rRNA gene sequences and belong to the planctomycete lineage defined by the genus Planctomyces, being most closely related to Planctomyces limnophilus DSM 3776T (86.9–87.1 % sequence similarity). However, strain MPL7T showed only 28 % DNA–DNA hybridization with P. limnophilus DSM 3776T. Compared with currently described members of the genus Planctomyces, the isolates from northern wetlands do not form long and distinctive stalks, have greater tolerance of acidic conditions and low temperatures, are more sensitive to NaCl, lack pigmentation and degrade a wider range of biopolymers. The data therefore suggest that strains MPL7T, MOB77 and SB2 represent a novel genus and species, for which the name Schlesneria paludicola gen. nov., sp. nov., is proposed. Strain MPL7T (=ATCC BAA-1393T =VKM B-2452T) is the type strain of Schlesneria paludicola.
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Schlesneria paludicola gen. nov., sp. nov., the first acidophilic member of the order Planctomycetales, from Sphagnum-dominated boreal wetlands.
International journal of systematic and evolutionary microbiology, 2007Co-Authors: Irina S Kulichevskaya, Anastasia O. Ivanova, Olga Baulina, Paul L. E. Bodelier, Svetlana E. Belova, G A Zavarzin, W. Irene C. Rijpstra, Jaap S Sinninghe Damsté, Svetlana N DedyshAbstract:Three strains of budding, ellipsoid-shaped and rosette-forming bacteria were isolated from acidic Sphagnum-dominated boreal wetlands of northern Russia and were designated strains MPL7T, MOB77 and SB2. The presence of crateriform pits and numerous fibrillar appendages on the cell surface and an unusual spur-like projection on one pole of the cell indicated a planctomycete morphotype. These isolates are moderately acidophilic, mesophilic organisms capable of growth at pH values between 4.2 and 7.5 (with an optimum at pH 5.0-6.2) and at temperatures between 4 and 32 degrees C (optimum 15-26 degrees C). The major fatty acids are C16:0 and C16:1omega7c; the major quinone is MK-6. The G+C content of the DNA is 54.4-56.5 mol%. Strains MPL7T, MOB77 and SB2 possess nearly identical 16S rRNA gene sequences and belong to the planctomycete lineage defined by the genus Planctomyces, being most closely related to Planctomyces limnophilus DSM 3776T (86.9-87.1% sequence similarity). However, strain MPL7T showed only 28% DNA-DNA hybridization with P. limnophilus DSM 3776T. Compared with currently described members of the genus Planctomyces, the isolates from northern wetlands do not form long and distinctive stalks, have greater tolerance of acidic conditions and low temperatures, are more sensitive to NaCl, lack pigmentation and degrade a wider range of biopolymers. The data therefore suggest that strains MPL7T, MOB77 and SB2 represent a novel genus and species, for which the name Schlesneria paludicola gen. nov., sp. nov., is proposed. Strain MPL7T (=ATCC BAA-1393T=VKM B-2452T) is the type strain of Schlesneria paludicola.
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Detection of representatives of the Planctomycetes in Sphagnum peat bogs by molecular and cultivation approaches
Microbiology, 2006Co-Authors: Irina S Kulichevskaya, T. A. Pankratov, Svetlana N DedyshAbstract:By means of fluorescence in situ hybridization with 16S rRNA-targeted oligonucleotide probes (FISH), it has been shown that members of the phylum Planctomycetes represent a numerically significant bacterial group in boreal Sphagnum peat bogs. The population size of planctomycetes in oxic layers of the peat bog profile was in the range of 0.4–2.0 × 107 cells per g of wet peat, comprising 4 to 13% of the total bacterial cell number. A novel effective approach that combined a traditional cultivation technique with FISH-mediated monitoring of the target organism during the isolation procedure has been developed for the isolation of planctomycetes. Using this approach, we succeeded in isolating several peat-inhabiting planctomycetes in a pure culture. Sequencing of the 16S rRNA genes from two of these isolates, strains A10 and MPL7, showed that they belonged to the planctomycete lineages defined by the genera Gemmata and Planctomyces, respectively. The 16S rRNA gene sequence similarity between strains A10 and MPL7 and the phylogenetically closest organisms, namely, Gemmata obscuriglobus and Planctomyces limnophilus, was only 90%. These results suggest that the indigenous planctomycetes inhabiting Sphagnum peat bogs are so far unknown organisms.
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Detection of representatives of the Planctomycetes in Sphagnum peat bogs by molecular and cultivation methods
Mikrobiologiia, 2006Co-Authors: I S Kulichevskaia, T. A. Pankratov, Svetlana N DedyshAbstract:By means of fluorescence in situ hybridization with 16S rRNA-targeted oligonucleotide probes (FISH), it has been shown that members of the phylum Planctomycetes represent a numerically significant bacterial group in boreal Sphagnum peat bogs. The population size of planctomycetes in oxic layers of the peat bog profile was in the range of 0.4-2.0 x 10(7) cells per g of wet peat, comprising 4 to 13% of the total bacterial cell number. A novel effective approach that combined a traditional cultivation technique with FISH-mediated monitoring of the target organism during the isolation procedure has been developed for the isolation of planctomycetes. Using this approach, we succeeded in isolating several peat-inhabiting planctomycetes in a pure culture. Sequencing of the 16S rRNA genes from two of these isolates, strains A10 and MPL7, showed that they belonged to the planctomycete lineages defined by the genera Gemmata and Planctomyces, respectively. The 16S rRNA gene sequence similarity between strains A10 and MPL7 and the phylogenetically closest organisms, namely, Gemmata obscuriglobus and Planctomyces limnophilus, was only 90%. These results suggest that the indigenous planctomycetes inhabiting Sphagnum peat bogs are so far unknown organisms.
Guangming Zeng - One of the best experts on this subject based on the ideXlab platform.
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Denitrification of landfill leachate under different hydraulic retention time in a two-stage anoxic/oxic combined membrane bioreactor process: Performances and bacterial community.
Bioresource technology, 2017Co-Authors: Jianbo Liu, Panyue Zhang, Yonghui Song, Guangming Zeng, Yuan Tian, Siyu Wang, Sun Chen, Zhiyong TianAbstract:Abstract Two-stage anoxic/oxic combined membrane bioreactor (A/O-A/O-MBR) process was used to treat leachate generated from Shenyang Laohuchong landfill, and the effect of hydraulic retention time (HRT) was studied. A long HRT of 9 d and a short HRT of 5 d showed negative effect on the stability of process, resulting in a higher organic concentration of effluent than that with a HRT of 7 d, while the highest removal of chemical oxygen demand (COD), ammonia (NH4+-N) and total nitrogen (TN) were achieved with a HRT of 7 d, which was 82.4%, 99.1% and 75.3% respectively. The analysis of microbial communities by high-throughput sequencing showed that phyla Proteobacteria and Bacteroidetes were the dominant bacteria, which accounted for 36.63–42.39%, 29.21–38.66%, respectively. For genus classification, the most representative of Ferruginibacter, unclassified-Saprospiraceae and Nitrosomonas accounted for 20.76–35.11% totally. The other communities, including Nitrobacter, Planctomyces, Rhodobacteraceae and Nitrospirae, were also developed for organic degradation and denitrification.
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two stage anoxic oxic combined membrane bioreactor system for landfill leachate treatment pollutant removal performances and microbial community
Bioresource Technology, 2017Co-Authors: Jianbo Liu, Haibo Zhang, Panyue Zhang, Xiying Gou, Yonghui Song, Zhiyong Tian, Guangming ZengAbstract:In this study, a laboratory-scale two-stage anoxic/oxic (A/O) combined membrane bioreactor (MBR) was operated for 113d for the treatment of landfill leachate. The average removal of chemical oxygen demand (COD), ammonia (NH4+-N) and total nitrogen (TN) achieved 80.60%, 99.04% and 74.87%, respectively. A mass balance evaluation suggested that the removal of COD, NH4+-N and TN occurred mainly in the second A/O process, and the total removal capacity of COD, NH4+-N and TN were 125.60g/d, 24.35g/d and 22.40g/d, respectively. High-throughput sequencing analysis indicated that the Proteobacteria (44.57-50.36%), Bacteroidetes (22.09-27.25%), Planctomycetes (6.94-8.47%), Firmicutes (3.31-4.53%) and Chloroflexi (3.13-4.80%) were the dominated phyla in the bacterial community during the operation period. At the genus level, Nitrosomonas, Nitrobacter, Planctomyces, Saprospiraceae and Pseudomonas showed relatively high abundance, which played an important role in the removal of pollutants.
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Two-stage anoxic/oxic combined membrane bioreactor system for landfill leachate treatment: Pollutant removal performances and microbial community.
Bioresource technology, 2017Co-Authors: Jianbo Liu, Haibo Zhang, Panyue Zhang, Xiying Gou, Yonghui Song, Zhiyong Tian, Guangming ZengAbstract:In this study, a laboratory-scale two-stage anoxic/oxic (A/O) combined membrane bioreactor (MBR) was operated for 113d for the treatment of landfill leachate. The average removal of chemical oxygen demand (COD), ammonia (NH4+-N) and total nitrogen (TN) achieved 80.60%, 99.04% and 74.87%, respectively. A mass balance evaluation suggested that the removal of COD, NH4+-N and TN occurred mainly in the second A/O process, and the total removal capacity of COD, NH4+-N and TN were 125.60g/d, 24.35g/d and 22.40g/d, respectively. High-throughput sequencing analysis indicated that the Proteobacteria (44.57-50.36%), Bacteroidetes (22.09-27.25%), Planctomycetes (6.94-8.47%), Firmicutes (3.31-4.53%) and Chloroflexi (3.13-4.80%) were the dominated phyla in the bacterial community during the operation period. At the genus level, Nitrosomonas, Nitrobacter, Planctomyces, Saprospiraceae and Pseudomonas showed relatively high abundance, which played an important role in the removal of pollutants.
Zhiyong Tian - One of the best experts on this subject based on the ideXlab platform.
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Denitrification of landfill leachate under different hydraulic retention time in a two-stage anoxic/oxic combined membrane bioreactor process: Performances and bacterial community.
Bioresource technology, 2017Co-Authors: Jianbo Liu, Panyue Zhang, Yonghui Song, Guangming Zeng, Yuan Tian, Siyu Wang, Sun Chen, Zhiyong TianAbstract:Abstract Two-stage anoxic/oxic combined membrane bioreactor (A/O-A/O-MBR) process was used to treat leachate generated from Shenyang Laohuchong landfill, and the effect of hydraulic retention time (HRT) was studied. A long HRT of 9 d and a short HRT of 5 d showed negative effect on the stability of process, resulting in a higher organic concentration of effluent than that with a HRT of 7 d, while the highest removal of chemical oxygen demand (COD), ammonia (NH4+-N) and total nitrogen (TN) were achieved with a HRT of 7 d, which was 82.4%, 99.1% and 75.3% respectively. The analysis of microbial communities by high-throughput sequencing showed that phyla Proteobacteria and Bacteroidetes were the dominant bacteria, which accounted for 36.63–42.39%, 29.21–38.66%, respectively. For genus classification, the most representative of Ferruginibacter, unclassified-Saprospiraceae and Nitrosomonas accounted for 20.76–35.11% totally. The other communities, including Nitrobacter, Planctomyces, Rhodobacteraceae and Nitrospirae, were also developed for organic degradation and denitrification.
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two stage anoxic oxic combined membrane bioreactor system for landfill leachate treatment pollutant removal performances and microbial community
Bioresource Technology, 2017Co-Authors: Jianbo Liu, Haibo Zhang, Panyue Zhang, Xiying Gou, Yonghui Song, Zhiyong Tian, Guangming ZengAbstract:In this study, a laboratory-scale two-stage anoxic/oxic (A/O) combined membrane bioreactor (MBR) was operated for 113d for the treatment of landfill leachate. The average removal of chemical oxygen demand (COD), ammonia (NH4+-N) and total nitrogen (TN) achieved 80.60%, 99.04% and 74.87%, respectively. A mass balance evaluation suggested that the removal of COD, NH4+-N and TN occurred mainly in the second A/O process, and the total removal capacity of COD, NH4+-N and TN were 125.60g/d, 24.35g/d and 22.40g/d, respectively. High-throughput sequencing analysis indicated that the Proteobacteria (44.57-50.36%), Bacteroidetes (22.09-27.25%), Planctomycetes (6.94-8.47%), Firmicutes (3.31-4.53%) and Chloroflexi (3.13-4.80%) were the dominated phyla in the bacterial community during the operation period. At the genus level, Nitrosomonas, Nitrobacter, Planctomyces, Saprospiraceae and Pseudomonas showed relatively high abundance, which played an important role in the removal of pollutants.
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Two-stage anoxic/oxic combined membrane bioreactor system for landfill leachate treatment: Pollutant removal performances and microbial community.
Bioresource technology, 2017Co-Authors: Jianbo Liu, Haibo Zhang, Panyue Zhang, Xiying Gou, Yonghui Song, Zhiyong Tian, Guangming ZengAbstract:In this study, a laboratory-scale two-stage anoxic/oxic (A/O) combined membrane bioreactor (MBR) was operated for 113d for the treatment of landfill leachate. The average removal of chemical oxygen demand (COD), ammonia (NH4+-N) and total nitrogen (TN) achieved 80.60%, 99.04% and 74.87%, respectively. A mass balance evaluation suggested that the removal of COD, NH4+-N and TN occurred mainly in the second A/O process, and the total removal capacity of COD, NH4+-N and TN were 125.60g/d, 24.35g/d and 22.40g/d, respectively. High-throughput sequencing analysis indicated that the Proteobacteria (44.57-50.36%), Bacteroidetes (22.09-27.25%), Planctomycetes (6.94-8.47%), Firmicutes (3.31-4.53%) and Chloroflexi (3.13-4.80%) were the dominated phyla in the bacterial community during the operation period. At the genus level, Nitrosomonas, Nitrobacter, Planctomyces, Saprospiraceae and Pseudomonas showed relatively high abundance, which played an important role in the removal of pollutants.
Jianbo Liu - One of the best experts on this subject based on the ideXlab platform.
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Denitrification of landfill leachate under different hydraulic retention time in a two-stage anoxic/oxic combined membrane bioreactor process: Performances and bacterial community.
Bioresource technology, 2017Co-Authors: Jianbo Liu, Panyue Zhang, Yonghui Song, Guangming Zeng, Yuan Tian, Siyu Wang, Sun Chen, Zhiyong TianAbstract:Abstract Two-stage anoxic/oxic combined membrane bioreactor (A/O-A/O-MBR) process was used to treat leachate generated from Shenyang Laohuchong landfill, and the effect of hydraulic retention time (HRT) was studied. A long HRT of 9 d and a short HRT of 5 d showed negative effect on the stability of process, resulting in a higher organic concentration of effluent than that with a HRT of 7 d, while the highest removal of chemical oxygen demand (COD), ammonia (NH4+-N) and total nitrogen (TN) were achieved with a HRT of 7 d, which was 82.4%, 99.1% and 75.3% respectively. The analysis of microbial communities by high-throughput sequencing showed that phyla Proteobacteria and Bacteroidetes were the dominant bacteria, which accounted for 36.63–42.39%, 29.21–38.66%, respectively. For genus classification, the most representative of Ferruginibacter, unclassified-Saprospiraceae and Nitrosomonas accounted for 20.76–35.11% totally. The other communities, including Nitrobacter, Planctomyces, Rhodobacteraceae and Nitrospirae, were also developed for organic degradation and denitrification.
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two stage anoxic oxic combined membrane bioreactor system for landfill leachate treatment pollutant removal performances and microbial community
Bioresource Technology, 2017Co-Authors: Jianbo Liu, Haibo Zhang, Panyue Zhang, Xiying Gou, Yonghui Song, Zhiyong Tian, Guangming ZengAbstract:In this study, a laboratory-scale two-stage anoxic/oxic (A/O) combined membrane bioreactor (MBR) was operated for 113d for the treatment of landfill leachate. The average removal of chemical oxygen demand (COD), ammonia (NH4+-N) and total nitrogen (TN) achieved 80.60%, 99.04% and 74.87%, respectively. A mass balance evaluation suggested that the removal of COD, NH4+-N and TN occurred mainly in the second A/O process, and the total removal capacity of COD, NH4+-N and TN were 125.60g/d, 24.35g/d and 22.40g/d, respectively. High-throughput sequencing analysis indicated that the Proteobacteria (44.57-50.36%), Bacteroidetes (22.09-27.25%), Planctomycetes (6.94-8.47%), Firmicutes (3.31-4.53%) and Chloroflexi (3.13-4.80%) were the dominated phyla in the bacterial community during the operation period. At the genus level, Nitrosomonas, Nitrobacter, Planctomyces, Saprospiraceae and Pseudomonas showed relatively high abundance, which played an important role in the removal of pollutants.
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Two-stage anoxic/oxic combined membrane bioreactor system for landfill leachate treatment: Pollutant removal performances and microbial community.
Bioresource technology, 2017Co-Authors: Jianbo Liu, Haibo Zhang, Panyue Zhang, Xiying Gou, Yonghui Song, Zhiyong Tian, Guangming ZengAbstract:In this study, a laboratory-scale two-stage anoxic/oxic (A/O) combined membrane bioreactor (MBR) was operated for 113d for the treatment of landfill leachate. The average removal of chemical oxygen demand (COD), ammonia (NH4+-N) and total nitrogen (TN) achieved 80.60%, 99.04% and 74.87%, respectively. A mass balance evaluation suggested that the removal of COD, NH4+-N and TN occurred mainly in the second A/O process, and the total removal capacity of COD, NH4+-N and TN were 125.60g/d, 24.35g/d and 22.40g/d, respectively. High-throughput sequencing analysis indicated that the Proteobacteria (44.57-50.36%), Bacteroidetes (22.09-27.25%), Planctomycetes (6.94-8.47%), Firmicutes (3.31-4.53%) and Chloroflexi (3.13-4.80%) were the dominated phyla in the bacterial community during the operation period. At the genus level, Nitrosomonas, Nitrobacter, Planctomyces, Saprospiraceae and Pseudomonas showed relatively high abundance, which played an important role in the removal of pollutants.
