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  1 / 115 MEDLINE  
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PMID:29185938
Autor:Pal D; Bhardwaj A; Sudan SK; Kaur N; Kumari M; Bisht B; Vyas B; Krishnamurthi S; Mayilraj S
Endereço:1​MTCC- Microbial Type Culture Collection and Gene Bank, CSIR- Institute of Microbial Technology, Chandigarh 160 036, India.
Título:Thauera propionica sp. nov., isolated from downstream sediment sample of the river Ganges, Kanpur, India.
Fonte:Int J Syst Evol Microbiol; 68(1):341-346, 2018 Jan.
ISSN:1466-5034
País de publicação:England
Idioma:eng
Resumo:A Gram-stain-negative, non-endospore-producing, short-rod strain, KNDSS-Mac4 , was isolated from a downstream sediment sample of the river Ganges, Kanpur, India and studied by using the polyphasic taxonomic approach. 16S rRNA gene sequence analysis uncovered that the strain had similarity to species of the genus Thauera and formed a distinct phylogenetic cluster with Thauera humireducens KACC16524 . However, KNDSS-Mac4 showed closest phylogenetic affiliation to Thauera aminoaromatica DSM 14742 with 16S rRNA gene sequence similarity of 98.7 % followed by Thauera phenylacetica DSM 14743 (98.6 %), Thauera chlorobenzoica (98.2 %), T. humireducens KACC16524 (98.2 %), Thauera selenatis ATCC 55363 (98.2 %) and Thauera mechernichensis DSM 12266 (98.0 %). The digital DNA-DNA hybridization and average nucleotide identity values between strain KNDSS-Mac4 and the two most closely related taxa, T. aminoaromatica DSM 14742 and T. phenylacetica DSM 14743 , were 26.0, 26.7 and 84.0, 84.3 % respectively. Major lipids present were phosphatidylglycerol, three unknown aminophospholipids, phosphatidylmethylethanolamine, two unidentified lipids and Q-8 as the only ubiquonone. The major cellular fatty acids present were C16 : 1 ω6c/C16 : 1ω7c and C16 : 0. The DNA G+C content of strain KNDSS-Mac4 was 65.9 %. Based on data from phenotypic tests and the genotypic differences of strain KNDSS-Mac4 from its closest phylogenetic relatives, it is evident that this isolate should be regarded as a new species. It is proposed that strain KNDSS-Mac4 should be classified in the genus Thauera as a novel species, Thauerapropionica sp. nov. The type strain is KNDSS-Mac4 (=KCTC 52820 =VTCC-B-910017 ).
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (DNA, Bacterial); 0 (Fatty Acids); 0 (Phospholipids); 0 (RNA, Ribosomal, 16S); 1339-63-5 (Ubiquinone); EJ27X76M46 (coenzyme Q10)


  2 / 115 MEDLINE  
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PMID:27521780
Autor:Du R; Cao S; Wang S; Niu M; Peng Y
Endereço:National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China.
Título:Performance of partial denitrification (PD)-ANAMMOX process in simultaneously treating nitrate and low C/N domestic wastewater at low temperature.
Fonte:Bioresour Technol; 219:420-429, 2016 Nov.
ISSN:1873-2976
País de publicação:England
Idioma:eng
Resumo:The simultaneous treatment of nitrate (NO3(-)-N∼50mgL(-1)) and domestic wastewater (ammonia (NH4(+)-N)∼60.6mgL(-1), COD∼166.3mgL(-1)) via a novel partial denitrification (PD)-ANaerobic AMMonium OXidation (ANAMMOX) process was investigated at low temperature (12.9∼15.1°C). Results showed that desirable performance was achieved with average NO3(-)-N, NH4(+)-N and COD removal efficiencies of 89.5%, 97.6% and 78.7%, respectively. However, deteriorated sludge settleability in PD reactor was observed during operation, which bulked with serious sludge wash-out, leading to excess NO3(-)-N remaining in PD effluent. Fortunately, a satisfactory nitrogen removal was still achieved due to the occurrence of partial denitrification in ANAMMOX reactor. This was demonstrated by high-throughput sequencing, which revealed that the high nitrite (NO2(-)-N) production denitrifying bacteria of Thauera was detected (6.1%). ANAMMOX (above 70%) maintained the dominant pathway for nitrogen removal, and Candidatus Jettenia was identified as the major ANAMMOX species accounted for 2.7%.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Nitrates); 0 (Waste Water); 7664-41-7 (Ammonia)


  3 / 115 MEDLINE  
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PMID:27507824
Autor:Tiedt O; Mergelsberg M; Boll K; Müller M; Adrian L; Jehmlich N; von Bergen M; Boll M
Endereço:Faculty of Biology, Microbiology, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany.
Título:ATP-Dependent C-F Bond Cleavage Allows the Complete Degradation of 4-Fluoroaromatics without Oxygen.
Fonte:MBio; 7(4), 2016 Aug 09.
ISSN:2150-7511
País de publicação:United States
Idioma:eng
Resumo:UNLABELLED: Complete biodegradation of the abundant and persistent fluoroaromatics requires enzymatic cleavage of an arylic C-F bond, probably the most stable single bond of a biodegradable organic molecule. While in aerobic microorganisms defluorination of fluoroaromatics is initiated by oxygenases, arylic C-F bond cleavage has never been observed in the absence of oxygen. Here, an oxygen-independent enzymatic aryl fluoride bond cleavage is described during the complete degradation of 4-fluorobenzoate or 4-fluorotoluene to CO2 and HF in the denitrifying Thauera aromatica: the ATP-dependent defluorination of 4-fluorobenzoyl-coenzyme A (4-F-BzCoA) to benzoyl-coenzyme A (BzCoA) and HF, catalyzed by class I BzCoA reductase (BCR). Adaptation to growth with the fluoroaromatics was accomplished by the downregulation of a promiscuous benzoate-CoA ligase and the concomitant upregulation of 4-F-BzCoA-defluorinating/dearomatizing BCR on the transcriptional level. We propose an unprecedented mechanism for reductive arylic C-F bond cleavage via a Birch reduction-like mechanism resulting in a formal nucleophilic aromatic substitution. In the proposed anionic 4-fluorodienoyl-CoA transition state, fluoride elimination to BzCoA is favored over protonation to a fluorinated cyclic dienoyl-CoA. IMPORTANCE: Organofluorides are produced as pesticides, pharmaceuticals, and other chemicals and comprise approximately one quarter of all organic compounds in the pharmaceutical and agricultural sectors; they are considered a growing class of environmentally relevant persistent pollutants. Especially in the case of fluoroaromatics, biodegradation is hampered by the extreme stability of the arylic C-F bond. In aerobic microorganisms, degradation proceeds via oxygenase-dependent C-F bond cleavage reactions, whereas the enzymes involved in the degradation of fluoroaromatics at anoxic sites are unknown. Here we report a strategy for the complete biodegradation of a fluoroaromatic to CO2 and HF in a denitrifying bacterium via activation to a CoA ester, followed by oxygen-independent arylic C-F bond cleavage catalyzed by an ATP-dependent enzyme. This reaction, in conjunction with a transcriptional adaptation to fluorinated growth substrates, is essential for the anoxic biodegradation of 4-fluorobenzoate/4-F-toluene and probably other fluoroaromatics.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (Benzoates); 142M471B3J (Carbon Dioxide); 3FPU23BG52 (Toluene); 8L70Q75FXE (Adenosine Triphosphate); RGL5YE86CZ (Hydrofluoric Acid); S88TT14065 (Oxygen); V5ROO2HOU4 (4-fluorobenzoic acid)


  4 / 115 MEDLINE  
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PMID:27118314
Autor:Marmulla R; Cala EP; Markert S; Schweder T; Harder J
Endereço:Department of Microbiology, Max Planck Institute for Marine Microbiology, Celsiusstr. 1, D-28359, Bremen, Germany.
Título:The anaerobic linalool metabolism in Thauera linaloolentis 47 Lol.
Fonte:BMC Microbiol; 16:76, 2016 Apr 27.
ISSN:1471-2180
País de publicação:England
Idioma:eng
Resumo:BACKGROUND: The betaproteobacterium Thauera linaloolentis 47Lol(T) was isolated on the tertiary monoterpene alcohol (R,S)-linalool as sole carbon and energy source under denitrifying conditions. Growth experiments indicated the formation of geraniol and geranial. Thus, a 3,1-hydroxyl-Δ(1)-Δ(2)-mutase (linalool isomerase) activity may initiate the degradation, followed by enzymes of the acyclic terpene utilization (Atu) and leucine/isovalerate utilization (Liu) pathways that were extensively studied in Pseudomonas spp. growing on citronellol or geraniol. RESULTS: A transposon mutagenesis yielded 39 transconjugants that could not grow anaerobically on linalool and nitrate in liquid medium. The deficiencies were apparently based on gene functions required to overcome the toxicity of linalool, but not due to inactivation of genes in the degradation pathway. Growing cultures formed geraniol and geranial transiently, but also geranic acid. Analysis of expressed proteins detected several enzymes of the Atu and Liu pathways. The draft genome of T. linaloolentis 47Lol(T) had atu and liu genes with homology to those of Pseudomonas spp.. CONCLUSION: The in comparison to monoterpenes larger toxicity of monoterpene alcohols is defeated by several modifications of the cellular structure and metabolism in Thauera linaloolentis 47Lol(T). The acyclic terpene utilization pathway is used in T. linaloolentis 47Lol(T) during growth on (R,S)-linalool and nitrate under anoxic conditions. This is the first experimental verification of an active Atu pathway outside of the genus Pseudomonas.
Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
Nome de substância:0 (Bacterial Proteins); 0 (DNA Transposable Elements); 0 (Monoterpenes); D81QY6I88E (linalool)


  5 / 115 MEDLINE  
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PMID:27070573
Autor:Szaleniec M; Heider J
Endereço:Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, Kraków 30-239, Poland. ncszalen@cyfronet.pl.
Título:Modeling of the Reaction Mechanism of Enzymatic Radical C-C Coupling by Benzylsuccinate Synthase.
Fonte:Int J Mol Sci; 17(4):514, 2016 Apr 07.
ISSN:1422-0067
País de publicação:Switzerland
Idioma:eng
Resumo:Molecular modeling techniques and density functional theory calculations were performed to study the mechanism of enzymatic radical C-C coupling catalyzed by benzylsuccinate synthase (BSS). BSS has been identified as a glycyl radical enzyme that catalyzes the enantiospecific fumarate addition to toluene initiating its anaerobic metabolism in the denitrifying bacterium Thauera aromatica, and this reaction represents the general mechanism of toluene degradation in all known anaerobic degraders. In this work docking calculations, classical molecular dynamics (MD) simulations, and DFT+D2 cluster modeling was employed to address the following questions: (i) What mechanistic details of the BSS reaction yield the most probable molecular model? (ii) What is the molecular basis of enantiospecificity of BSS? (iii) Is the proposed mechanism consistent with experimental observations, such as an inversion of the stereochemistry of the benzylic protons, syn addition of toluene to fumarate, exclusive production of (R)-benzylsuccinate as a product and a kinetic isotope effect (KIE) ranging between 2 and 4? The quantum mechanics (QM) modeling confirms that the previously proposed hypothetical mechanism is the most probable among several variants considered, although C-H activation and not C-C coupling turns out to be the rate limiting step. The enantiospecificity of the enzyme seems to be enforced by a thermodynamic preference for binding of fumarate in the pro(R) orientation and reverse preference of benzyl radical attack on fumarate in pro(S) pathway which results with prohibitively high energy barrier of the radical quenching. Finally, the proposed mechanism agrees with most of the experimental observations, although the calculated intrinsic KIE from the model (6.5) is still higher than the experimentally observed values (4.0) which suggests that both C-H activation and radical quenching may jointly be involved in the kinetic control of the reaction.
Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
Nome de substância:0 (Fumarates); 0 (Succinates); 103-40-2 (benzylsuccinate); 3FPU23BG52 (Toluene); EC 4.1.- (Carbon-Carbon Lyases); EC 4.1.99.- (benzylsuccinate synthase)


  6 / 115 MEDLINE  
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PMID:27002232
Autor:Ma C; Yang G; Zhang Q; Zhuang L; Zhou S
Endereço:Hainan Provincial Key Laboratory of Quality and Safety for Tropical Fruits and Vegetables, Analysis and Testing Center, Chinese Academy of Tropical Agriculture Sciences, Haikou 571101, PR China.
Título:Complete genome of Thauera humireducens SgZ-1, a potential bacterium for environmental remediation and wastewater treatment.
Fonte:J Biotechnol; 225:59-60, 2016 May 10.
ISSN:1873-4863
País de publicação:Netherlands
Idioma:eng
Resumo:Thauera humireducens SgZ-1(T) (KACC 16524(T)=CCTCC M2011497(T)), isolated from the anode biofilm of a microbial fuel cell, is able to grow under anaerobic conditions via the oxidation of various organic compounds coupled to the reduction of humus, Fe(III) species and nitrate. Addtionally, the strain has the ability to produce exopolysaccharide (EPS). Here, we report the complete genome sequence of T. humiruducens SgZ-1(T), which is relevant to metabolism of electron donors and acceptors for environmental remediation and wastewater treatment.
Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T


  7 / 115 MEDLINE  
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PMID:26979141
Autor:Marmulla R; Safaric B; Markert S; Schweder T; Harder J
Endereço:Department of Microbiology, Max Planck Institute for Marine Microbiology, Celsiusstr. 1, D-28359, Bremen, Germany.
Título:Linalool isomerase, a membrane-anchored enzyme in the anaerobic monoterpene degradation in Thauera linaloolentis 47Lol.
Fonte:BMC Biochem; 17:6, 2016 Mar 15.
ISSN:1471-2091
País de publicação:England
Idioma:eng
Resumo:BACKGROUND: Thauera linaloolentis 47Lol uses the tertiary monoterpene alcohol (R,S)-linalool as sole carbon and energy source under denitrifying conditions. The conversion of linalool to geraniol had been observed in carbon-excess cultures, suggesting the presence of a 3,1-hydroxyl-Δ(1)-Δ(2)-mutase (linalool isomerase) as responsible enzyme. To date, only a single enzyme catalyzing such a reaction is described: the linalool dehydratase/isomerase (Ldi) from Castellaniella defragrans 65Phen acting only on (S)-linalool. RESULTS: The linalool isomerase activity was located in the inner membrane. It was enriched by subcellular fractionation and sucrose gradient centrifugation. MALDI-ToF MS analysis of the enriched protein identified the corresponding gene named lis that codes for the protein in the strain with the highest similarity to the Ldi. Linalool isomerase is predicted to have four transmembrane helices at the N-terminal domain and a cytosolic domain. Enzyme activity required a reductant for activation. A specific activity of 3.42 ± 0.28 nkat mg * protein(-1) and a kM value of 455 ± 124 µM were determined for the thermodynamically favored isomerization of geraniol to both linalool isomers at optimal conditions of pH 8 and 35 °C. CONCLUSION: The linalool isomerase from T. linaloolentis 47Lol represents a second member of the enzyme class 5.4.4.4, next to the linalool dehydratase/isomerase from C. defragrans 65Phen. Besides considerable amino acid sequence similarity both enzymes share common characteristics with respect to substrate affinity, pH and temperature optima, but differ in the dehydratase activity and the turnover of linalool isomers.
Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
Nome de substância:0 (Monoterpenes); 0 (Recombinant Proteins); 0 (Terpenes); D81QY6I88E (linalool); EC 4.2.1.- (Hydro-Lyases); EC 5.- (Isomerases); L837108USY (geraniol)


  8 / 115 MEDLINE  
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PMID:26874439
Autor:Xie B; Liu B; Yi Y; Yang L; Liang D; Zhu Y; Liu H
Endereço:School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China; Institution of Environmental Biology and Life Support Technology, Beihang University, Beijing 100191, China; International Joint Research Center of Aerospace Biotechnology & Medical Engineering, Beih
Título:Microbiological mechanism of the improved nitrogen and phosphorus removal by embedding microbial fuel cell in Anaerobic-Anoxic-Oxic wastewater treatment process.
Fonte:Bioresour Technol; 207:109-17, 2016 May.
ISSN:1873-2976
País de publicação:England
Idioma:eng
Resumo:Anaerobic-Anoxic-Oxic (AA/O) wastewater treatment process is a widely used wastewater treatment process for simultaneous nitrogen and phosphorus removal. Microbial fuel cell (MFC) can generate electricity and treat the organic wastewater simultaneously. Our previous research showed that embedding MFC in AA/O wastewater treatment process could enhance the pollutants removal efficiency. However, the mechanism was not clear. In this study, a lab-scale corridor-style AA/O reactor with MFC embedded was operated and both the total nitrogen and total phosphorus removal efficiencies were enhanced. DGGE and Illumina Miseq results demonstrated that both the microbial community structures on the surface of the cathode and in the suspensions of cathode chamber have been changed. The percentage of Thauera and Emticicia, identified as denitrifying bacteria, increased significantly in the suspension liquid when the MFC was embedded in the AA/O reactor. Moreover, the genus Rheinheimera were significantly enriched on the cathode surface, which might contribute to both the nitrogen removal enhancement and electricity generation.
Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
Nome de substância:0 (RNA, Ribosomal, 16S); 0 (Waste Water); 0 (Water Pollutants, Chemical); 27YLU75U4W (Phosphorus); 9007-49-2 (DNA); N762921K75 (Nitrogen)


  9 / 115 MEDLINE  
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PMID:26816093
Autor:Ma J; Wang Z; Li H; Park HD; Wu Z
Endereço:State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, Shanghai, 200092, People's Republic of China.
Título:Metagenomes reveal microbial structures, functional potentials, and biofouling-related genes in a membrane bioreactor.
Fonte:Appl Microbiol Biotechnol; 100(11):5109-21, 2016 Jun.
ISSN:1432-0614
País de publicação:Germany
Idioma:eng
Resumo:Metagenomic sequencing was used to investigate the microbial structures, functional potentials, and biofouling-related genes in a membrane bioreactor (MBR). The results showed that the microbial community in the MBR was highly diverse. Notably, function analysis of the dominant genera indicated that common genes from different phylotypes were identified for important functional potentials with the observation of variation of abundances of genes in a certain taxon (e.g., Dechloromonas). Despite maintaining similar metabolic functional potentials with a parallel full-scale conventional activated sludge (CAS) system due to treating the identical wastewater, the MBR had more abundant nitrification-related bacteria and coding genes of ammonia monooxygenase, which could well explain its excellent ammonia removal in the low-temperature period. Furthermore, according to quantification of the genes involved in exopolysaccharide and extracellular polymeric substance (EPS) protein metabolism, the MBR did not show a much different potential in producing EPS compared to the CAS system, and bacteria from the membrane biofilm had lower abundances of genes associated with EPS biosynthesis and transport compared to the activated sludge in the MBR.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (DNA, Bacterial); 0 (Polymers); 0 (Sewage); 0 (Waste Water)


  10 / 115 MEDLINE  
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PMID:26810146
Autor:Liu C; Xu J; Lee DJ; Yu D; Liu L
Endereço:College of Chemical Engineering, China University of Petroleum, Qingdao 266580, China.
Título:Denitrifying sulfide removal process on high-tetracycline wastewater.
Fonte:Bioresour Technol; 205:254-7, 2016 Apr.
ISSN:1873-2976
País de publicação:England
Idioma:eng
Resumo:Antibiotics wastewater from tetracycline (TC) production unit can have high levels of chemical oxygen demand, ammonium and sulfate and up to a few hundreds of milligrams per liter of TC. Denitrifying sulfide removal (DSR) process is set up for simultaneously removal of sulfur, carbon and nitrogen from waters. The DSR process was for the first time studied for treating TC wastewaters. The TC stress has no adverse effects on removal rates of nitrate and acetate; however, it moderately deteriorated sulfide removal rates and S(0) accumulation rates when the concentration is higher than 100mgL(-1) TC. The Thauera sp., and Pseudomonas sp. present the heterotrophs and Sulfurovum sp. presented the autotroph for the present DSR reactions. The high tolerance of TC stress by the tested consortium was explained by the excess production of extracellular polymeric substances at high TC concentration, which can bind with TC for minimizing its inhibition effects.
Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
Nome de substância:0 (Acetates); 0 (Ammonium Compounds); 0 (Anti-Bacterial Agents); 0 (Nitrates); 0 (Sulfates); 0 (Sulfides); 0 (Waste Water); 70FD1KFU70 (Sulfur); 7440-44-0 (Carbon); F8VB5M810T (Tetracycline); N762921K75 (Nitrogen)



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