1
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Suman J, Sredlova K, Fraraccio S, Jerabkova M, Strejcek M, Kabickova H, Cajthaml T, Uhlik O. Transformation of hydroxylated polychlorinated biphenyls by bacterial 2-hydroxybiphenyl 3-monooxygenase. CHEMOSPHERE 2024; 349:140909. [PMID: 38070605 DOI: 10.1016/j.chemosphere.2023.140909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 08/18/2023] [Accepted: 12/04/2023] [Indexed: 12/17/2023]
Abstract
Monohydroxylated PCBs (OH-PCBs) are an (eco)toxicologically significant group of compounds, as they arise from the oxidation of polychlorinated biphenyls (PCBs) and, at the same time, may exert even more severe toxic effects than their parent PCB molecules. Despite having been widely detected in environmental samples, plants, and animals, information on the fate of OH-PCBs in the environment is scarce, including on the enzymatic machinery behind their degradation. To date, only a few bacterial taxa capable of OH-PCB transformation have been reported. In this study, we aimed to obtain a deeper insight into the transformation of OH-PCBs in soil bacteria and isolated a Pseudomonas sp. strain P1B16 based on its ability to use o-phenylphenol (2-PP) which, when exposed to the Delor 103-derived OH-PCB mixture, depleted a wide spectrum of mono-, di, and trichlorinated OH-PCBs. In the P1B16 genome, a region designated as hbp was identified, which bears a set of putative genes involved in the transformation of OH-PCBs, namely hbpA encoding for a putative flavin-dependent 2-hydroxybiphenyl monooxygenase, hbpC (2,3-dihydroxybiphenyl-1,2-dioxygenase), hbpD (2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoate hydrolase), and the transcriptional activator-encoding gene hbpR. The hbpA coding sequence was heterologously expressed, purified, and its substrate specificity was investigated towards the Delor 103-derived OH-PCB mixture, individual OH-PCBs, and multiple (chlorinated) phenolics. Apart from 2-PP and 2-chlorophenol, HbpA was also demonstrated to transform a range of OH-PCBs, including a 3-hydroxy-2,2',4',5,5'-pentachlorobiphenyl. Importantly, this is the first direct evidence of HbpA homologs being involved in the degradation of OH-PCBs. Moreover, using a P1B16-based biosensor strain, the specific induction of hbp genes by 2-PP, 3-phenylphenol, 4-phenylphenol, and the OH-PCB mixture was demonstrated. This study provides direct evidence on the specific enzymatic machinery responsible for the transformation of OH-PCBs in bacteria, with many implications in ecotoxicology, environmental restoration, and microbial ecology in habitats burdened with PCB contamination.
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Affiliation(s)
- Jachym Suman
- Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, University of Chemistry and Technology, Technicka 3, 162 08, Prague, Czech Republic.
| | - Kamila Sredlova
- Institute for Environmental Studies, Faculty of Science, Charles University, Benatska 2, 128 01, Prague 2, Czech Republic; Institute of Microbiology of the Czech Academy of Sciences, Videnska 1083, 142 00, Prague, Czech Republic
| | - Serena Fraraccio
- Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, University of Chemistry and Technology, Technicka 3, 162 08, Prague, Czech Republic
| | - Martina Jerabkova
- Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, University of Chemistry and Technology, Technicka 3, 162 08, Prague, Czech Republic
| | - Michal Strejcek
- Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, University of Chemistry and Technology, Technicka 3, 162 08, Prague, Czech Republic
| | - Hana Kabickova
- Military Health Institute, Ministry of Defence of the Czech Republic, U Vojenske Nemocnice 1200, 169 02, Prague, Czech Republic
| | - Tomas Cajthaml
- Institute for Environmental Studies, Faculty of Science, Charles University, Benatska 2, 128 01, Prague 2, Czech Republic; Institute of Microbiology of the Czech Academy of Sciences, Videnska 1083, 142 00, Prague, Czech Republic
| | - Ondrej Uhlik
- Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, University of Chemistry and Technology, Technicka 3, 162 08, Prague, Czech Republic.
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Hara T, Takatsuka Y. Aerobic polychlorinated biphenyl-degrading bacteria isolated from the Tohoku region of Japan are not regionally endemic. Can J Microbiol 2022; 68:191-202. [PMID: 35020498 DOI: 10.1139/cjm-2021-0056] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In the Tohoku region of Japan, 72% of the land comprises mountain forest zones. During winter, severe climatic conditions include heavy snowfall. In such an environment, which is considered high in biodiversity, we assumed that aerobic bacteria would be diverse and would possess the ability to degrade polychlorinated biphenyls (PCBs). In this study, 78 environmental samples were collected from the Tohoku region and 56 aerobic PCB-degrading bacterial strains were isolated. They belonged to the genera Achromobacter, Rhodococcus, Pseudomonas, Stenotrophomonas, Comamonas, Pigmentiphaga, Xenophilus, Acinetobacter, and Pandoraea. Previously reported aerobic PCB-degrading bacterial strains isolated in Japan belonged to the same genera, except that the genera Acidovorax and Bacillus were not identified in the present study. In particular, the isolated Comamonas testosteroni strains YAZ2 and YU14-111 had high PCB-degrading abilities. Analysis of the sequences of the YAZ2 and YU14-111 strains showed that the gene structures of the bph operon, which encode enzymes associated with PCB degradation, were the same as those of the Acidovorax sp. KKS102 strain. Moreover, 2,3-biphenyl dioxygenase activity was responsible for the degradation characteristics of all the isolated strains. Overall, this study suggests that aerobic PCB-degrading bacteria are not specifically endemic to the Tohoku region but distributed across Japan.
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Affiliation(s)
- Tomijiro Hara
- Environmental Microbiology Research Section, Laboratory for Complex Energy Processes, Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan.,Environmental Microbiology Research Section, Laboratory for Complex Energy Processes, Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
| | - Yumiko Takatsuka
- Environmental Microbiology Research Section, Laboratory for Complex Energy Processes, Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan.,Environmental Microbiology Research Section, Laboratory for Complex Energy Processes, Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan
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Ito K. Mechanisms of aerobic dechlorination of hexachlorobenzene and pentachlorophenol by Nocardioides sp. PD653. JOURNAL OF PESTICIDE SCIENCE 2021; 46:373-381. [PMID: 34908898 PMCID: PMC8640678 DOI: 10.1584/jpestics.j21-04] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Accepted: 05/31/2021] [Indexed: 06/14/2023]
Abstract
We sought to elucidate the mechanisms underlying the aerobic dechlorination of the persistent organic pollutants hexachlorobenzene (HCB) and pentachlorophenol (PCP). We performed genomic and heterologous expression analyses of dehalogenase genes in Nocardioides sp. PD653, the first bacterium found to be capable of mineralizing HCB via PCP under aerobic conditions. The hcbA1A2A3 and hcbB1B2B3 genes, which were involved in catalysing the aerobic dechlorination of HCB and PCP, respectively, were identified and characterized; they were classified as members of the two-component flavin-diffusible monooxygenase family. This was subsequently verified by biochemical analysis; aerobic dechlorination activity was successfully reconstituted in vitro in the presence of flavin, NADH, the flavin reductase HcbA3, and the HCB monooxygenase HcbA1. These findings will contribute to the implementation of in situ bioremediation of HCB- or PCP-contaminated sites, as well as to a better understanding of bacterial evolution apropos their ability to degrade heavily chlorinated anthropogenic compounds under aerobic conditions.
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Affiliation(s)
- Koji Ito
- National Agriculture and Food Research Organization, Institute for Agro-Environmental Sciences, 3–1–3 Kannondai, Tsukuba-city, Ibaraki 305–8604, Japan
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Xu T, Liu T, Jiang D, Yuan Z, Jia X. Attainment and characterization of a microbial consortium that efficiently degrades biphenyl and related substances. Biochem Eng J 2021. [DOI: 10.1016/j.bej.2021.108073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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5
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Chen SC, Budhraja R, Adrian L, Calabrese F, Stryhanyuk H, Musat N, Richnow HH, Duan GL, Zhu YG, Musat F. Novel clades of soil biphenyl degraders revealed by integrating isotope probing, multi-omics, and single-cell analyses. ISME JOURNAL 2021; 15:3508-3521. [PMID: 34117322 PMCID: PMC8630052 DOI: 10.1038/s41396-021-01022-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Revised: 05/12/2021] [Accepted: 05/21/2021] [Indexed: 11/23/2022]
Abstract
Most microorganisms in the biosphere remain uncultured and poorly characterized. Although the surge in genome sequences has enabled insights into the genetic and metabolic properties of uncultured microorganisms, their physiology and ecological roles cannot be determined without direct probing of their activities in natural habitats. Here we employed an experimental framework coupling genome reconstruction and activity assays to characterize the largely uncultured microorganisms responsible for aerobic biodegradation of biphenyl as a proxy for a large class of environmental pollutants, polychlorinated biphenyls. We used 13C-labeled biphenyl in contaminated soils and traced the flow of pollutant-derived carbon into active cells using single-cell analyses and protein–stable isotope probing. The detection of 13C-enriched proteins linked biphenyl biodegradation to the uncultured Alphaproteobacteria clade UBA11222, which we found to host a distinctive biphenyl dioxygenase gene widely retrieved from contaminated environments. The same approach indicated the capacity of Azoarcus species to oxidize biphenyl and suggested similar metabolic abilities for species of Rugosibacter. Biphenyl oxidation would thus represent formerly unrecognized ecological functions of both genera. The quantitative role of these microorganisms in pollutant degradation was resolved using single-cell-based uptake measurements. Our strategy advances our understanding of microbially mediated biodegradation processes and has general application potential for elucidating the ecological roles of uncultured microorganisms in their natural habitats.
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Affiliation(s)
- Song-Can Chen
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, 04318, Leipzig, Germany
| | - Rohit Budhraja
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, 04318, Leipzig, Germany
| | - Lorenz Adrian
- Department Environmental Biotechnology, Helmholtz Centre for Environmental Research-UFZ, Leipzig, Germany.,Chair of Geobiotechnology, Technische Universität Berlin, 13355, Berlin, Germany
| | - Federica Calabrese
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, 04318, Leipzig, Germany
| | - Hryhoriy Stryhanyuk
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, 04318, Leipzig, Germany
| | - Niculina Musat
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, 04318, Leipzig, Germany
| | - Hans-Hermann Richnow
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, 04318, Leipzig, Germany
| | - Gui-Lan Duan
- State Key Lab of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 100085, Beijing, China
| | - Yong-Guan Zhu
- State Key Lab of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 100085, Beijing, China. .,Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, 361021, Xiamen, China.
| | - Florin Musat
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, 04318, Leipzig, Germany.
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Ahmad F, Zhu D, Sun J. Bacterial chemotaxis: a way forward to aromatic compounds biodegradation. ENVIRONMENTAL SCIENCES EUROPE 2020; 32:52. [DOI: 10.1186/s12302-020-00329-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Accepted: 03/23/2020] [Indexed: 07/23/2024]
Abstract
AbstractWorldwide industrial development has released hazardous polycyclic aromatic compounds into the environment. These pollutants need to be removed to improve the quality of the environment. Chemotaxis mechanism has increased the bioavailability of these hydrophobic compounds to microorganisms. The mechanism, however, is poorly understood at the ligand and chemoreceptor interface. Literature is unable to furnish a compiled review of already published data on up-to-date research on molecular aspects of chemotaxis mechanism, ligand and receptor-binding mechanism, and downstream signaling machinery. Moreover, chemotaxis-linked biodegradation of aromatic compounds is required to understand the chemotaxis role in biodegradation better. To fill this knowledge gap, the current review is an attempt to cover PAHs occurrence, chemical composition, and potential posed risks to humankind. The review will cover the aspects of microbial signaling mechanism, the structural diversity of methyl-accepting chemotaxis proteins at the molecular level, discuss chemotaxis mechanism role in biodegradation of aromatic compounds in model bacterial genera, and finally conclude with the potential of bacterial chemotaxis for aromatics biodegradation.
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Pimviriyakul P, Wongnate T, Tinikul R, Chaiyen P. Microbial degradation of halogenated aromatics: molecular mechanisms and enzymatic reactions. Microb Biotechnol 2020; 13:67-86. [PMID: 31565852 PMCID: PMC6922536 DOI: 10.1111/1751-7915.13488] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 09/01/2019] [Accepted: 09/03/2019] [Indexed: 12/12/2022] Open
Abstract
Halogenated aromatics are used widely in various industrial, agricultural and household applications. However, due to their stability, most of these compounds persist for a long time, leading to accumulation in the environment. Biological degradation of halogenated aromatics provides sustainable, low-cost and environmentally friendly technologies for removing these toxicants from the environment. This minireview discusses the molecular mechanisms of the enzymatic reactions for degrading halogenated aromatics which naturally occur in various microorganisms. In general, the biodegradation process (especially for aerobic degradation) can be divided into three main steps: upper, middle and lower metabolic pathways which successively convert the toxic halogenated aromatics to common metabolites in cells. The most difficult step in the degradation of halogenated aromatics is the dehalogenation step in the middle pathway. Although a variety of enzymes are involved in the degradation of halogenated aromatics, these various pathways all share the common feature of eventually generating metabolites for utilizing in the energy-producing metabolic pathways in cells. An in-depth understanding of how microbes employ various enzymes in biodegradation can lead to the development of new biotechnologies via enzyme/cell/metabolic engineering or synthetic biology for sustainable biodegradation processes.
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Affiliation(s)
- Panu Pimviriyakul
- Department of BiotechnologyFaculty of Engineering and Industrial TechnologySilpakorn UniversityNakhon Pathom73000Thailand
| | - Thanyaporn Wongnate
- School of Biomolecular Science and EngineeringVidyasirimedhi Institute of Science and Technology (VISTEC)Wangchan ValleyRayong21210Thailand
| | - Ruchanok Tinikul
- Department of Biochemistry and Center for Excellence in Protein and Enzyme TechnologyFaculty of ScienceMahidol UniversityBangkok10400Thailand
| | - Pimchai Chaiyen
- School of Biomolecular Science and EngineeringVidyasirimedhi Institute of Science and Technology (VISTEC)Wangchan ValleyRayong21210Thailand
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8
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Jia Y, Wang J, Ren C, Nahurira R, Khokhar I, Wang J, Fan S, Yan Y. Identification and characterization of a meta-cleavage product hydrolase involved in biphenyl degradation from Arthrobacter sp. YC-RL1. Appl Microbiol Biotechnol 2019; 103:6825-6836. [PMID: 31240368 DOI: 10.1007/s00253-019-09956-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2019] [Revised: 05/25/2019] [Accepted: 05/28/2019] [Indexed: 12/27/2022]
Abstract
Polychlorinated biphenyls (PCBs) are a group of persistent organic pollutants (POPs) widely existing in the environment. Arthrobacter sp. YC-RL1 is a biphenyl-degrading bacterium that shows metabolic versatility towards aromatic compounds. A 2-hydroxy-6-oxo-6-phenylhexa-2, 4-dienoate (HOPDA) hydrolase (BphD) gene involved in the biodegradation of biphenyl was cloned from strain YC-RL1 and heterologously expressed in Escherichia coli BL21 (DE3). The recombinant BphDYC-RL1 was purified and characterized. BphDYC-RL1 showed the highest activity at 45 °C and pH 7. It was stable under a wide range of temperature (20-50 °C). The enzyme had a Km value of 0.14 mM, Kcat of 11.61 s-1, and Vmax of 0.027 U/mg. Temperature dependence catalysis exhibited a biphasic Arrhenius Plot with a transition at 20 °C. BphDYC-RL1 was inactivated by SDS, Tween 20, Tween 80, Trition X-100, DTT, CHAPS, NBS, PMSF, and DEPC, but insensitive to EDTA. Site-directed mutagenesis of the active-site residues revealed that the catalytic triad residues (Ser115, His275, and Asp247) of BphDYC-RL1 were necessary for its activity. The investigation of BphDYC-RL1 not only provides new potential enzyme resource for the biodegradation of biphenyl but also helps deepen our understanding on the catalytic process and mechanism.
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Affiliation(s)
- Yang Jia
- Graduate School, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Junhuan Wang
- Graduate School, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Chao Ren
- Graduate School, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Ruth Nahurira
- Graduate School, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Ibatsam Khokhar
- Graduate School, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Jiayi Wang
- Graduate School, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Shuanghu Fan
- Graduate School, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Yanchun Yan
- Graduate School, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
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Hirose J, Fujihara H, Watanabe T, Kimura N, Suenaga H, Futagami T, Goto M, Suyama A, Furukawa K. Biphenyl/PCB Degrading bph Genes of Ten Bacterial Strains Isolated from Biphenyl-Contaminated Soil in Kitakyushu, Japan: Comparative and Dynamic Features as Integrative Conjugative Elements (ICEs). Genes (Basel) 2019; 10:genes10050404. [PMID: 31137913 PMCID: PMC6563109 DOI: 10.3390/genes10050404] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Revised: 05/18/2019] [Accepted: 05/20/2019] [Indexed: 11/21/2022] Open
Abstract
We sequenced the entire genomes of ten biphenyl/PCB degrading bacterial strains (KF strains) isolated from biphenyl-contaminated soil in Kitakyushu, Japan. All the strains were Gram-negative bacteria belonging to β- and γ-proteobacteria. Out of the ten strains, nine strains carried a biphenyl catabolic bph gene cluster as integrative conjugative elements (ICEs), and they were classified into four groups based on the structural features of the bph genes. Group I (five strains) possessed bph genes that were very similar to the ones in Pseudomonasfurukawaii KF707 (formerly Pseudomonas pseudoalcaligenes KF707), which is one of the best characterized biphenyl-utilizing strains. This group of strains carried salicylate catabolic sal genes that were approximately 6-kb downstream of the bph genes. Group II (two strains) possessed bph and sal genes similar to the ones in KF707, but these strains lacked the bphX region between bphC and bphD, which is involved in the downstream catabolism of biphenyl. These bph-sal clusters in groups I and II were located on an integrative conjugative element that was larger than 110 kb, and they were named ICEbph-sal. Our previous study demonstrated that the ICEbph-sal of Pseudomonas putida KF715 in group II existed both in an integrated form in the chromosome (referred to as ICEbph-salKF715 (integrated)) and in a extrachromosomal circular form (referred to as ICEbph-sal (circular)) (previously called pKF715A, 483 kb) in the stationary culture. The ICEbph-sal was transferred from KF715 into P. putida AC30 and P. putida KT2440 with high frequency, and it was maintained stably as an extrachromosomal circular form. The ICEbph-salKF715 (circular) in these transconjugants was further transferred to P. putida F39/D and then integrated into the chromosome in one or two copies. Meanwhile, group III (one strain) possessed bph genes, but not sal genes. The nucleotide sequences of the bph genes in this group were less conserved compared to the genes of the strains belonging to groups I and II. Currently, there is no evidence to indicate that the bph genes in group III are carried by a mobile element. Group IV (two strains) carried bph genes as ICEs (59–61 kb) that were similar to the genes found in Tn4371 from Cupriavidus oxalacticus A5 and ICEKKS1024677 from the Acidovorax sp. strain KKS102. Our study found that bph gene islands have integrative functions, are transferred among soil bacteria, and are diversified through modification.
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Affiliation(s)
- Jun Hirose
- Department of Applied Chemistry, Faculty of Engineering, University of Miyazaki, Miyazaki 889-2192, Japan.
| | - Hidehiko Fujihara
- Department of Food and Fermentation Sciences, Faculty of Food and Nutrition Sciences, Beppu University, Beppu 874-8501, Japan.
| | - Takahito Watanabe
- Research Institute for Sustainable Humanosphere, Kyoto University, Uji 611-0011, Japan.
| | - Nobutada Kimura
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Japan.
| | - Hikaru Suenaga
- Biotechnology Research Institute for Drug Discovery, National Institute of Advanced Industrial Science and Technology (AIST), Tokyo 135-0064, Japan.
| | - Taiki Futagami
- Education and Research Center for Fermentation Studies, Faculty of Agriculture, Kagoshima University, Kagoshima 890-0065, Japan.
| | - Masatoshi Goto
- Faculty of Agriculture, Saga University, Saga 840-8502, Japan.
| | - Akiko Suyama
- Department of Food and Fermentation Sciences, Faculty of Food and Nutrition Sciences, Beppu University, Beppu 874-8501, Japan.
| | - Kensuke Furukawa
- Department of Food and Fermentation Sciences, Faculty of Food and Nutrition Sciences, Beppu University, Beppu 874-8501, Japan.
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Polychlorinated Biphenyls (PCBs): Environmental Fate, Challenges and Bioremediation. MICROORGANISMS FOR SUSTAINABILITY 2019. [DOI: 10.1007/978-981-13-7462-3_8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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11
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Fedi S, Cappelletti M, Sandri F, Turner RJ, Zannoni D. Some facts about the respiratory enzymes of Pseudomonas pseudoalcaligenes KF707 recently renamed as Pseudomonas furukawaii sp. nov., type strain KF707. Int J Syst Evol Microbiol 2018; 68:3066-3067. [PMID: 30024361 DOI: 10.1099/ijsem.0.002923] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Kimura and co-workers (Kimura N et al. Int J Syst Evol Microbiol 2018;68:1429-1435) recently proposed renaming the obligate aerobe Pseudomonas pseudoalcaligenes KF707 as Pseudomonas furukawiisp. nov. type strain KF707. Since the first quasi-complete genome sequence of KF707 was reported in 2012 (accession number: PRJNA83639) numerous reports on chemotaxis and function/composition of the respiratory redox chain of KF707 have been published, demonstrating that KF707 contains three cheA genes for aerobic motility, four cytochrome oxidases of c(c)aa3- and cbb3-type and one bd-type quinol oxidase. With this background in mind, it has been quite a surprise to read within Table 1 of the paper by Kimura et al. that strain KF707 is phenotypically characterized as cytochrome oxidase-negative. Further, Table 1 also reports that KF707 is β-galactosidase-positive, an affirmation that is not consistent with results documented in the current literature. In this present 'Letter to the Editor' we show that Kimura et al. have contradicted themselves and provided inaccurate information in respect to the respiratory phenotypic features of P. furukawii. Based on this, an official corrigendum is requested since the publication, as it is, blurs the credibility of the International Journal of Systematic and Evolutionary Microbiology.
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Affiliation(s)
- Stefano Fedi
- 1Department of Pharmacy and BioTechnology, University of Bologna, Bologna, Italy
| | - Martina Cappelletti
- 1Department of Pharmacy and BioTechnology, University of Bologna, Bologna, Italy
| | - Federica Sandri
- 1Department of Pharmacy and BioTechnology, University of Bologna, Bologna, Italy
| | - Raymond J Turner
- 2Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Davide Zannoni
- 1Department of Pharmacy and BioTechnology, University of Bologna, Bologna, Italy
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Kimura N, Watanabe T, Suenaga H, Fujihara H, Futagami T, Goto M, Hanada S, Hirose J. Pseudomonas furukawaii sp. nov., a polychlorinated biphenyl-degrading bacterium isolated from biphenyl-contaminated soil in Japan. Int J Syst Evol Microbiol 2018; 68:1429-1435. [PMID: 29595413 DOI: 10.1099/ijsem.0.002670] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Strain KF707T was isolated from a biphenyl-contaminated site in Kitakyushu, Japan. Analysis of 16S rRNA gene sequences, retrieved from the whole-genome sequence, revealed that the isolate was closely related to members of the genus Pseudomonas, sharing the highest sequence similarities with Pseudomonas balearica strain SP1402T (DSM 6083) (97.8 %). The DNA G+C chromosome and plasmid content of strain KF707T were 65.5 and 60.5 mol%. The major cellular fatty acids were iso-C15 : 0 and C16 : 1ω7c/C16 : 1ω6c. Polyphasic analysis indicated that strain KF707T represents a novel species of the genus Pseudomonas, for which the name Pseudomonas furukawaii sp. nov. is proposed. The type strain is KF707T (=DSM 10086T=NBRC 110670T).
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Affiliation(s)
- Nobutada Kimura
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
| | - Takahito Watanabe
- Research Institute for Sustainable Humanosphere, Kyoto University, Uji, Japan
| | - Hikaru Suenaga
- Biotechnology Research Institute for Drug Discovery, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
| | | | - Taiki Futagami
- Research Center for Fermentation Studies, Faculty of Agriculture, Kagoshima University, Kagoshima, Japan
| | - Masatoshi Goto
- Department of Applied Biochemistry and Food Science, Saga University, Saga, Japan
| | - Satoshi Hanada
- Graduate School of Science and Engineering, Tokyo Metropolitan University, Hachioji, Japan
| | - Jun Hirose
- Department of Applied Chemistry, Faculty of Engineering, University of Miyazaki, Miyazaki, Japan
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Ridl J, Suman J, Fraraccio S, Hradilova M, Strejcek M, Cajthaml T, Zubrova A, Macek T, Strnad H, Uhlik O. Complete genome sequence of Pseudomonas alcaliphila JAB1 (=DSM 26533), a versatile degrader of organic pollutants. Stand Genomic Sci 2018; 13:3. [PMID: 29435100 PMCID: PMC5796565 DOI: 10.1186/s40793-017-0306-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 12/06/2017] [Indexed: 12/25/2022] Open
Abstract
In this study, following its isolation from contaminated soil, the genomic sequence of Pseudomonas alcaliphila strain JAB1 (=DSM 26533), a biphenyl-degrading bacterium, is reported and analyzed in relation to its extensive degradative capabilities. The P. alcaliphila JAB1 genome (GenBank accession no. CP016162) consists of a single 5.34 Mbp-long chromosome with a GC content of 62.5%. Gene function was assigned to 3816 of the 4908 predicted genes. The genome harbors a bph gene cluster, permitting degradation of biphenyl and many congeners of polychlorinated biphenyls (PCBs), a ben gene cluster, enabling benzoate and its derivatives to be degraded, and phe gene cluster, which permits phenol degradation. In addition, P. alcaliphila JAB1 is capable of cometabolically degrading cis-1,2-dichloroethylene (cDCE) when grown on phenol. The strain carries both catechol and protocatechuate branches of the β-ketoadipate pathway, which is used to funnel the pollutants to the central metabolism. Furthermore, we propose that clustering of MALDI-TOF MS spectra with closest phylogenetic relatives should be used when taxonomically classifying the isolated bacterium; this, together with 16S rRNA gene sequence and chemotaxonomic data analyses, enables more precise identification of the culture at the species level.
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Affiliation(s)
- Jakub Ridl
- 1Department of Genomics and Bioinformatics, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Jachym Suman
- 2Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, University of Chemistry and Technology, Prague, Czech Republic
| | - Serena Fraraccio
- 2Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, University of Chemistry and Technology, Prague, Czech Republic
| | - Miluse Hradilova
- 1Department of Genomics and Bioinformatics, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Michal Strejcek
- 2Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, University of Chemistry and Technology, Prague, Czech Republic
| | - Tomas Cajthaml
- 3Laboratory of Environmental Biotechnology, Institute of Microbiology, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Andrea Zubrova
- 2Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, University of Chemistry and Technology, Prague, Czech Republic
| | - Tomas Macek
- 2Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, University of Chemistry and Technology, Prague, Czech Republic
| | - Hynek Strnad
- 1Department of Genomics and Bioinformatics, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Ondrej Uhlik
- 2Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, University of Chemistry and Technology, Prague, Czech Republic
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Sandri F, Fedi S, Cappelletti M, Calabrese FM, Turner RJ, Zannoni D. Biphenyl Modulates the Expression and Function of Respiratory Oxidases in the Polychlorinated-Biphenyls Degrader Pseudomonas pseudoalcaligenes KF707. Front Microbiol 2017; 8:1223. [PMID: 28713350 PMCID: PMC5492768 DOI: 10.3389/fmicb.2017.01223] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Accepted: 06/16/2017] [Indexed: 11/13/2022] Open
Abstract
Pseudomonas pseudoalcaligenes KF707 is a soil bacterium which is known for its capacity to aerobically degrade harmful organic compounds such as polychlorinated biphenyls (PCBs) using biphenyl as co-metabolite. Here we provide the first genetic and functional analysis of the KF707 respiratory terminal oxidases in cells grown with two different carbon sources: glucose and biphenyl. We identified five terminal oxidases in KF707: two c(c)aa3 type oxidases (Caa3 and Ccaa3), two cbb3 type oxidases (Cbb31 and Cbb32), and one bd type cyanide-insensitive quinol oxidase (CIO). While the activity and expression of both Cbb31 and Cbb32 oxidases was prevalent in glucose grown cells as compared to the other oxidases, the activity and expression of the Caa3 oxidase increased considerably only when biphenyl was used as carbon source in contrast to the Cbb32 oxidase which was repressed. Further, the respiratory activity and expression of CIO was up-regulated in a Cbb31 deletion strain as compared to W.T. whereas the CIO up-regulation was not present in Cbb32 and C(c)aa3 deletion mutants. These results, together, reveal that both function and expression of cbb3 and caa3 type oxidases in KF707 are modulated by biphenyl which is the co-metabolite needed for the activation of the PCBs-degradation pathway.
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Affiliation(s)
- Federica Sandri
- Department of Pharmacy and Biotechnology, University of BolognaBologna, Italy
| | - Stefano Fedi
- Department of Pharmacy and Biotechnology, University of BolognaBologna, Italy
| | - Martina Cappelletti
- Department of Pharmacy and Biotechnology, University of BolognaBologna, Italy
| | - Francesco M Calabrese
- Department of Biosciences, Biotechnology and Pharmacological Sciences, University of Bari "Aldo Moro"Bari, Italy.,Department of Biology, University of Bari "Aldo Moro"Bari, Italy
| | - Raymond J Turner
- Department of Biological Sciences, University of CalgaryCalgary, AB, Canada
| | - Davide Zannoni
- Department of Pharmacy and Biotechnology, University of BolognaBologna, Italy
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15
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Complete Genome Sequence of the Polychlorinated Biphenyl-Degrading Bacterium Pseudomonas putida KF715 (NBRC 110667) Isolated from Biphenyl-Contaminated Soil. GENOME ANNOUNCEMENTS 2017; 5:5/7/e01624-16. [PMID: 28209826 PMCID: PMC5313618 DOI: 10.1128/genomea.01624-16] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Pseudomonas putida KF715 (NBRC 110667) utilizes biphenyl as a sole source of carbon and degrades polychlorinated biphenyls (PCBs). Here, we report a complete genome sequence of the KF715 strain, which comprises a circular chromosome and four plasmids. Biphenyl catabolic genes were located on the largest plasmid, pKF715A.
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16
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Vergani L, Mapelli F, Zanardini E, Terzaghi E, Di Guardo A, Morosini C, Raspa G, Borin S. Phyto-rhizoremediation of polychlorinated biphenyl contaminated soils: An outlook on plant-microbe beneficial interactions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 575:1395-1406. [PMID: 27717569 DOI: 10.1016/j.scitotenv.2016.09.218] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Revised: 09/28/2016] [Accepted: 09/28/2016] [Indexed: 05/18/2023]
Abstract
Polychlorinated biphenyls (PCBs) are toxic chemicals, recalcitrant to degradation, bioaccumulative and persistent in the environment, causing adverse effects on ecosystems and human health. For this reason, the remediation of PCB-contaminated soils is a primary issue to be addressed. Phytoremediation represents a promising tool for in situ soil remediation, since the available physico-chemical technologies have strong environmental and economic impacts. Plants can extract and metabolize several xenobiotics present in the soil, but their ability to uptake and mineralize PCBs is limited due to the recalcitrance and low bioavailability of these molecules that in turn impedes an efficient remediation of PCB-contaminated soils. Besides plant degradation ability, rhizoremediation takes into account the capability of soil microbes to uptake, attack and degrade pollutants, so it can be seen as the most suitable strategy to clean-up PCB-contaminated soils. Microbes are in fact the key players of PCB degradation, performed under both aerobic and anaerobic conditions. In the rhizosphere, microbes and plants positively interact. Microorganisms can promote plant growth under stressed conditions typical of polluted soils. Moreover, in this specific niche, root exudates play a pivotal role by promoting the biphenyl catabolic pathway, responsible for microbial oxidative PCB metabolism, and by improving the overall PCB degradation performance. Besides rhizospheric microbial community, also the endophytic bacteria are involved in pollutant degradation and represent a reservoir of microbial resources to be exploited for bioremediation purposes. Here, focusing on plant-microbe beneficial interactions, we propose a review of the available results on PCB removal from soil obtained combining different plant and microbial species, mainly under simplified conditions like greenhouse experiments. Furthermore, we discuss the potentiality of "omics" approaches to identify PCB-degrading microbes, an aspect of paramount importance to design rhizoremediation strategies working efficiently under different environmental conditions, pointing out the urgency to expand research investigations to field scale.
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Affiliation(s)
- Lorenzo Vergani
- Department of Food, Environmental and Nutritional Sciences (DeFENS), University of Milan, Via Celoria 2, 20133 Milan, Italy
| | - Francesca Mapelli
- Department of Food, Environmental and Nutritional Sciences (DeFENS), University of Milan, Via Celoria 2, 20133 Milan, Italy
| | - Elisabetta Zanardini
- Department of Science and High Technology (DiSAT), University of Insubria, Via Valleggio 9, Como, Italy
| | - Elisa Terzaghi
- Department of Science and High Technology (DiSAT), University of Insubria, Via Valleggio 9, Como, Italy
| | - Antonio Di Guardo
- Department of Science and High Technology (DiSAT), University of Insubria, Via Valleggio 9, Como, Italy
| | - Cristiana Morosini
- Department of Science and High Technology (DiSAT), University of Insubria, Via G.B. Vico 46, Varese, Italy
| | - Giuseppe Raspa
- Department of Chemical Engineering Materials Environment (DICMA), Rome "La Sapienza" University, Via Eudossiana 18, Rome, Italy
| | - Sara Borin
- Department of Food, Environmental and Nutritional Sciences (DeFENS), University of Milan, Via Celoria 2, 20133 Milan, Italy.
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Blanco-Moreno R, Sáez LP, Luque-Almagro VM, Roldán MD, Moreno-Vivián C. Isolation of bacterial strains able to degrade biphenyl, diphenyl ether and the heat transfer fluid used in thermo-solar plants. N Biotechnol 2016; 35:35-41. [PMID: 27884748 DOI: 10.1016/j.nbt.2016.11.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 11/07/2016] [Accepted: 11/20/2016] [Indexed: 10/20/2022]
Abstract
Thermo-solar plants use eutectic mixtures of diphenyl ether (DE) and biphenyl (BP) as heat transfer fluid (HTF). Potential losses of HTF may contaminate soils and bioremediation is an attractive tool for its treatment. DE- or BP-degrading bacteria are known, but up to now bacteria able to degrade HTF mixture have not been described. Here, five bacterial strains which are able to grow with HTF or its separate components DE and BP as sole carbon sources have been isolated, either from soils exposed to HTF or from rhizospheric soils of plants growing near a thermo-solar plant. The organisms were identified by 16S rRNA gene sequencing as Achromobacter piechaudii strain BioC1, Pseudomonas plecoglossicida strain 6.1, Pseudomonas aeruginosa strains HBD1 and HBD3, and Pseudomonas oleovorans strain HBD2. Activity of 2,3-dihydroxybiphenyl dioxygenase (BphC), a key enzyme of the biphenyl upper degradation pathway, was detected in all isolates. Pseudomonas strains almost completely degraded 2000ppm HTF after 5-day culture, and even tolerated and grew in the presence of 150,000ppm HTF, being suitable candidates for in situ soil bioremediation. Degradation of both components of HTF is of particular interest since in the DE-degrader Sphingomonas sp. SS3, growth on DE or benzoate was strongly inhibited by addition of BP.
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Affiliation(s)
- Rafael Blanco-Moreno
- Departamento de Bioquímica y Biología Molecular, Edificio Severo Ochoa, 1ª Planta, Campus de Rabanales, Universidad de Córdoba, 14071 Córdoba, Spain
| | - Lara P Sáez
- Departamento de Bioquímica y Biología Molecular, Edificio Severo Ochoa, 1ª Planta, Campus de Rabanales, Universidad de Córdoba, 14071 Córdoba, Spain
| | - Víctor M Luque-Almagro
- Departamento de Bioquímica y Biología Molecular, Edificio Severo Ochoa, 1ª Planta, Campus de Rabanales, Universidad de Córdoba, 14071 Córdoba, Spain
| | - M Dolores Roldán
- Departamento de Bioquímica y Biología Molecular, Edificio Severo Ochoa, 1ª Planta, Campus de Rabanales, Universidad de Córdoba, 14071 Córdoba, Spain
| | - Conrado Moreno-Vivián
- Departamento de Bioquímica y Biología Molecular, Edificio Severo Ochoa, 1ª Planta, Campus de Rabanales, Universidad de Córdoba, 14071 Córdoba, Spain.
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18
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Musilova L, Ridl J, Polivkova M, Macek T, Uhlik O. Effects of Secondary Plant Metabolites on Microbial Populations: Changes in Community Structure and Metabolic Activity in Contaminated Environments. Int J Mol Sci 2016; 17:E1205. [PMID: 27483244 PMCID: PMC5000603 DOI: 10.3390/ijms17081205] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 06/20/2016] [Accepted: 07/15/2016] [Indexed: 12/19/2022] Open
Abstract
Secondary plant metabolites (SPMEs) play an important role in plant survival in the environment and serve to establish ecological relationships between plants and other organisms. Communication between plants and microorganisms via SPMEs contained in root exudates or derived from litter decomposition is an example of this phenomenon. In this review, the general aspects of rhizodeposition together with the significance of terpenes and phenolic compounds are discussed in detail. We focus specifically on the effect of SPMEs on microbial community structure and metabolic activity in environments contaminated by polychlorinated biphenyls (PCBs) and polyaromatic hydrocarbons (PAHs). Furthermore, a section is devoted to a complex effect of plants and/or their metabolites contained in litter on bioremediation of contaminated sites. New insights are introduced from a study evaluating the effects of SPMEs derived during decomposition of grapefruit peel, lemon peel, and pears on bacterial communities and their ability to degrade PCBs in a long-term contaminated soil. The presented review supports the "secondary compound hypothesis" and demonstrates the potential of SPMEs for increasing the effectiveness of bioremediation processes.
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Affiliation(s)
- Lucie Musilova
- Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, University of Chemistry and Technology Prague, Technicka 3, 166 28 Prague, Czech Republic.
| | - Jakub Ridl
- Department of Genomics and Bioinformatics, Institute of Molecular Genetics of the Czech Academy of Sciences, Videnska 1083, 142 20 Prague, Czech Republic.
| | - Marketa Polivkova
- Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, University of Chemistry and Technology Prague, Technicka 3, 166 28 Prague, Czech Republic.
| | - Tomas Macek
- Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, University of Chemistry and Technology Prague, Technicka 3, 166 28 Prague, Czech Republic.
| | - Ondrej Uhlik
- Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, University of Chemistry and Technology Prague, Technicka 3, 166 28 Prague, Czech Republic.
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19
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Borghese R, Canducci L, Musiani F, Cappelletti M, Ciurli S, Turner RJ, Zannoni D. On the role of a specific insert in acetate permeases (ActP) for tellurite uptake in bacteria: Functional and structural studies. J Inorg Biochem 2016; 163:103-109. [PMID: 27421695 DOI: 10.1016/j.jinorgbio.2016.06.029] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Revised: 06/14/2016] [Accepted: 06/23/2016] [Indexed: 11/17/2022]
Abstract
The oxyanion tellurite (TeO32-) is extremely toxic to bacterial cells. In Rhodobacter capsulatus, tellurite enters the cytosol by means of the high uptake-rate acetate permease RcActP2, encoded by one of the three actP genes present in this species (actP1, actP2 and actP3). Conversely, in Escherichia coli a low rate influx of the oxyanion is measured, which depends mainly on the phosphate transporter EcPitA, even though E. coli contains its own EcActP acetate permease. Here we report that when the actP2 gene from R. capsulatus is expressed in wild-type E. coli HB101 and in E. coli JW3460 ΔpitA mutant, the cellular intake of tellurite increases up to four times, suggesting intrinsic structural differences between EcActP and RcActP2. Indeed, a sequence analysis indicated the presence in RcActP2 of an insert of 15-16 residues, located between trans-membrane (TM) helices 6 and 7, which is absent in both EcActP and RcActP1. Based on this observation, the molecular models of homodimeric RcActP1 and RcActP2 were calculated and analyzed. In the RcActP2 model, the insert induces a perturbation in the conformation of the loop between TM helices 6 and 7, located at the RcActP2 dimerization interface. This perturbation opens a cavity on the periplasmic side that is closed, instead, in the RcActP1 model. This cavity also features an increase of the positive electric potential on the protein surface, an effect ascribed to specific residues Lys261, Lys281 and Arg560. We propose that this positively charged patch in RcActP2 is involved in recognition and translocation of the TeO32- anion, attributing to RcActP2 a greater ability as compared to RcActP1 to transport this inorganic poison inside the cells.
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Affiliation(s)
- Roberto Borghese
- Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy.
| | - Laura Canducci
- Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy
| | - Francesco Musiani
- Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy
| | - Martina Cappelletti
- Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy
| | - Stefano Ciurli
- Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy
| | - Raymond J Turner
- Department of Biological Sciences, University of Calgary, Calgary, Canada
| | - Davide Zannoni
- Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy
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20
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Fedi S, Barberi TT, Nappi MR, Sandri F, Booth S, Turner RJ, Attimonelli M, Cappelletti M, Zannoni D. The Role of cheA Genes in Swarming and Swimming Motility of Pseudomonas pseudoalcaligenes KF707. Microbes Environ 2016; 31:169-72. [PMID: 27151656 PMCID: PMC4912153 DOI: 10.1264/jsme2.me15164] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
A genome analysis of Pseudomonas pseudoalcaligenes KF707, a PCBs degrader and metal-resistant soil microorganism, revealed the presence of two novel gene clusters named che2 and che3, which were predicted to be involved in chemotaxis-like pathways, in addition to a che1 gene cluster. We herein report that the histidine kinase coding genes, cheA2 and cheA3, have no role in swimming or chemotaxis in P. pseudoalcaligenes KF707, in contrast to cheA1. However, the cheA1 and cheA2 genes were both necessary for cell swarming, whereas the cheA3 gene product had a negative effect on the optimal swarming phenotype of KF707 cells.
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Affiliation(s)
- Stefano Fedi
- Department of Pharmacy and Biotechnology, University of Bologna
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21
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Booth SC, Weljie AM, Turner RJ. Metabolomics reveals differences of metal toxicity in cultures of Pseudomonas pseudoalcaligenes KF707 grown on different carbon sources. Front Microbiol 2015; 6:827. [PMID: 26347721 PMCID: PMC4538868 DOI: 10.3389/fmicb.2015.00827] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 07/27/2015] [Indexed: 12/23/2022] Open
Abstract
Co-contamination of metals and organic pollutants is a global problem as metals interfere with the metabolism of complex organics by bacteria. Based on a prior observation that metal tolerance was altered by the sole carbon source being used for growth, we sought to understand how metal toxicity specifically affects bacteria using an organic pollutant as their sole carbon source. To this end metabolomics was used to compare cultures of Pseudomonas pseudoalcaligenes KF707 grown on either biphenyl (Bp) or succinate (Sc) as the sole carbon source in the presence of either aluminum (Al) or copper (Cu). Using multivariate statistical analysis it was found that the metals caused perturbations to more cellular processes in the cultures grown on Bp than those grown on Sc. Al induced many changes that were indicative of increased oxidative stress as metabolites involved in DNA damage and protection, the Krebs cycle and anti-oxidant production were altered. Cu also caused metabolic changes that were indicative of similar stress, as well as appearing to disrupt other key enzymes such as fumarase. Additionally, both metals caused the accumulation of Bp degradation intermediates indicating that they interfered with Bp metabolism. Together these results provide a basic understanding of how metal toxicity specifically affects bacteria at a biochemical level during the degradation of an organic pollutant and implicate the catabolism of this carbon source as a major factor that exacerbates metal toxicity.
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Affiliation(s)
- Sean C Booth
- Department of Biological Sciences, University of Calgary, Calgary AB, Canada
| | - Aalim M Weljie
- Department of Biological Sciences, University of Calgary, Calgary AB, Canada ; Department of Systems Pharmacology and Translational Therapeutics, Smilow Centre for Translational Research, Perelman School of Medicine, University of Pennsylvania, Philadelphia PA, USA
| | - Raymond J Turner
- Department of Biological Sciences, University of Calgary, Calgary AB, Canada ; Biofilm Research Group, University of Calgary, Calgary AB, Canada
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Draft Genome Sequence of Pseudomonas aeruginosa KF702 (NBRC 110665), a Polychlorinated Biphenyl-Degrading Bacterium Isolated from Biphenyl-Contaminated Soil. GENOME ANNOUNCEMENTS 2015; 3:3/3/e00517-15. [PMID: 25999557 PMCID: PMC4440971 DOI: 10.1128/genomea.00517-15] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Pseudomonas aeruginosa KF702 (NBRC 110665) utilizes biphenyl as a sole source of carbon and degrades polychlorinated biphenyls (PCBs). Here, we report the 7,167,540-bp draft genome sequence of KF702, which contains 6,714 coding sequences and a 65.8 mol% G+C content. The strain possesses genes for biphenyl catabolism and other genes that mediate degradation of various aromatic compounds.
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23
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Draft Genome Sequence of Pseudomonas abietaniphila KF701 (NBRC110664), a Polychlorinated Biphenyl-Degrading Bacterium Isolated from Biphenyl-Contaminated Soil. GENOME ANNOUNCEMENTS 2015; 3:3/3/e00473-15. [PMID: 25977441 PMCID: PMC4432347 DOI: 10.1128/genomea.00473-15] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Pseudomonas abietaniphila KF701 utilizes biphenyl as a sole source of carbon and degrades polychlorinated biphenyls (PCBs). Here, we report the 6,886,250-bp draft genome sequence of KF701, which contains 6,315 coding sequences and 59.4 mol% G+C content. The strain possesses genes for biphenyl catabolism and other genes that mediate the degradation of benzoate, salicylate, and phenol.
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24
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Draft Genome Sequence of the Polychlorinated Biphenyl-Degrading Bacterium Pseudomonas putida KF703 (NBRC 110666) Isolated from Biphenyl-Contaminated Soil. GENOME ANNOUNCEMENTS 2015; 3:3/2/e00142-15. [PMID: 25792060 PMCID: PMC4395060 DOI: 10.1128/genomea.00142-15] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Pseudomonas putida KF703 (NBRC 110666) utilizes biphenyl as a sole source of carbon and degrades polychlorinated biphenyls (PCBs). Here, we report the draft genome sequence of the KF703 strain, which provides insight into the molecular mechanisms of adaptation to an environment polluted by aromatic compounds.
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25
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Draft Genome Sequence of the Polychlorinated Biphenyl-Degrading Bacterium Cupriavidus basilensis KF708 (NBRC 110671) Isolated from Biphenyl-Contaminated Soil. GENOME ANNOUNCEMENTS 2015; 3:3/2/e00143-15. [PMID: 25792061 PMCID: PMC4395071 DOI: 10.1128/genomea.00143-15] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
We report the draft genome sequence of Cupriavidus basilensis KF708 (NBRC 110671), which utilizes biphenyl as a sole carbon source and degrades polychlorinated biphenyls (PCBs). The KF708 strain possesses genes for biphenyl catabolism and other genes involved in various aromatic compounds.
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26
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Draft Genome Sequence of Pseudomonas abietaniphila KF717 (NBRC 110669), Isolated from Biphenyl-Contaminated Soil in Japan. GENOME ANNOUNCEMENTS 2015; 3:3/2/e00059-15. [PMID: 25792041 PMCID: PMC4395067 DOI: 10.1128/genomea.00059-15] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Pseudomonas abietaniphila KF717 utilizes biphenyl as a sole source of carbon and energy and degrades polychlorinated biphenyls (PCBs). We report here the 6,930,016-bp genome sequence of this strain, which contains 6,323 predicted coding sequences (CDSs), including the biphenyl-utilizing bph gene cluster.
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27
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Taffi M, Paoletti N, Angione C, Pucciarelli S, Marini M, Liò P. Bioremediation in marine ecosystems: a computational study combining ecological modeling and flux balance analysis. Front Genet 2014; 5:319. [PMID: 25309577 PMCID: PMC4162388 DOI: 10.3389/fgene.2014.00319] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Accepted: 08/26/2014] [Indexed: 11/13/2022] Open
Abstract
The pressure to search effective bioremediation methodologies for contaminated ecosystems has led to the large-scale identification of microbial species and metabolic degradation pathways. However, minor attention has been paid to the study of bioremediation in marine food webs and to the definition of integrated strategies for reducing bioaccumulation in species. We propose a novel computational framework for analysing the multiscale effects of bioremediation at the ecosystem level, based on coupling food web bioaccumulation models and metabolic models of degrading bacteria. The combination of techniques from synthetic biology and ecological network analysis allows the specification of arbitrary scenarios of contaminant removal and the evaluation of strategies based on natural or synthetic microbial strains. In this study, we derive a bioaccumulation model of polychlorinated biphenyls (PCBs) in the Adriatic food web, and we extend a metabolic reconstruction of Pseudomonas putida KT2440 (iJN746) with the aerobic pathway of PCBs degradation. We assess the effectiveness of different bioremediation scenarios in reducing PCBs concentration in species and we study indices of species centrality to measure their importance in the contaminant diffusion via feeding links. The analysis of the Adriatic sea case study suggests that our framework could represent a practical tool in the design of effective remediation strategies, providing at the same time insights into the ecological role of microbial communities within food webs.
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Affiliation(s)
- Marianna Taffi
- Department of Biosciences and Biotechnology, University of CamerinoCamerino, Italy
| | - Nicola Paoletti
- Department of Computer Science, University of OxfordOxford, UK
| | | | - Sandra Pucciarelli
- Department of Biosciences and Biotechnology, University of CamerinoCamerino, Italy
| | - Mauro Marini
- National Research Council (CNR), Institute of Marine Sciences (ISMAR)Ancona, Italy
| | - Pietro Liò
- Computer Laboratory, University of CambridgeCambridge, UK
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28
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Mitsudome Y, Takahama M, Hirose J, Yoshida N. The use of nano-sized acicular material, sliding friction, and antisense DNA oligonucleotides to silence bacterial genes. AMB Express 2014; 4:70. [PMID: 25401071 PMCID: PMC4230895 DOI: 10.1186/s13568-014-0070-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Accepted: 08/15/2014] [Indexed: 11/15/2022] Open
Abstract
Viable bacterial cells impaled with a single particle of a nano-sized acicular material formed when a mixture containing the cells and the material was exposed to a sliding friction field between polystyrene and agar gel; hereafter, we refer to these impaled cells as penetrons. We have used nano-sized acicular material to establish a novel method for bacterial transformation. Here, we generated penetrons that carried antisense DNA adsorbed on nano-sized acicular material (α-sepiolite) by providing sliding friction onto the surface of agar gel; we then investigated whether penetron formation was applicable to gene silencing techniques. Antisense DNA was artificially synthesized as 15 or 90mer DNA oligonucleotides based on the sequences around the translation start codon of target mRNAs. Mixtures of bacterial cells with antisense DNA adsorbed on α-sepiolite were stimulated by sliding friction on the surface of agar gel for 60 s. Upon formation of Escherichia coli penetrons, β-lactamase and β-galactosidase expression was evaluated by counting the numbers of colonies formed on LB agar containing ampicillin and by measuring β-galactosidase activity respectively. The numbers of ampicillin resistant colonies and the β-galactosidase activity derived from penetrons bearing antisense DNA (90mer) was repressed to 15% and 25%, respectively, of that of control penetrons which lacked antisense DNA. Biphenyl metabolite, ring cleavage yellow compound produced by Pseudomonas pseudoalcaligenes penetron treated with antisense oligonucleotide DNA targeted to bphD increased higher than that lacking antisense DNA. This result indicated that expression of bphD in P. pseudoalcaligenes penetrons was repressed by antisense DNA that targeted bphD mRNA. Sporulation rates of Bacillus subtilis penetrons treated with antisense DNA (15mer) targeted to spo0A decreased to 24.4% relative to penetrons lacking antisense DNA. This novel method of gene silencing has substantial promise for elucidation of gene function in bacterial species that have been refractory to experimental introduction of exogenous DNA.
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Abbate C, Ambrosoli R, Minati JL, Gennari M, Arena M. Metabolic and molecular methods to evaluate the organoclay effects on a bacterial community. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2013; 179:39-44. [PMID: 23644274 DOI: 10.1016/j.envpol.2013.04.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Revised: 03/12/2013] [Accepted: 04/06/2013] [Indexed: 06/02/2023]
Abstract
The aim of this work was to evaluate the influence exerted by two different commercial organoclays (DELLITE 43B and DELLITE 67G) on a model microbial consortium using microbial metabolic characterization with BIOLOG system and denaturing gradient gel electrophoresis (DGGE) molecular approach. The information obtained from the molecular analyses, in their complex, account for the differences in species composition induced on the reference consortium by the contact with the organoclays under study. DELLITE 43B resulted to produce a marked selective effect, stimulating the quantitative increase especially of Pseudomonas pseudoalcaligenes. A weaker effect was found for DELLITE 67G. On the other hand, Biolog analyses indicated a depressing action exerted by DELLITE 43B on the metabolic activity of the model microbial consortium as a whole. The presence of P. pseudoalcaligenes and B. borstelensis in the bacterial community after the treatments confirmed that a positive change in the microbial structure consortium occurred.
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Affiliation(s)
- Cristina Abbate
- Dipartimento di Scienze delle Produzioni Agrarie e Alimentari, University of Catania, Via Santa Sofia 98, 95123 Catania, Italy.
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30
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Hernández-Sánchez V, Lang E, Wittich RM. The Three-Species Consortium of Genetically Improved Strains Cupriavidus necator RW112, Burkholderia xenovorans RW118, and Pseudomonas pseudoalcaligenes RW120 Grows with Technical Polychlorobiphenyl, Aroclor 1242. Front Microbiol 2013; 4:90. [PMID: 23658554 PMCID: PMC3647243 DOI: 10.3389/fmicb.2013.00090] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2012] [Accepted: 03/08/2013] [Indexed: 12/03/2022] Open
Abstract
Burkholderia xenovorans LB400, Cupriavidus necator H850, and Pseudomonas pseudoalcaligenes KF707 are bacterial strains able to mineralize biphenyl and to co-oxidize many of its halogenated derivatives (PCBs). Only strain LB400 also mineralizes a few mono- and dichlorobiphenyls, due to the presence of a functioning chlorocatechol pathway. Here, we used a Tn5-based minitransposon shuttle system to chromosomically introduce genes tcbRCDEF, encoding the chlorocatechol pathway into KF707, and genes cbdABC encoding a 2-chlorobenzoate 1,2-dioxygenase into KF707 and LB400, as well as transposon Tn4653 from the TOL plasmid, providing genes xylXYZL, encoding a broad-range toluate (methylbenzoate) dioxygenase and its dihydrodiol dehydrogenase, to extend the range for the mineralization of halogenated benzoates in LB400 and in KF707 through co-oxidation of halobenzoates into chlorocatechols. The engineered derivatives of LB400 and KF707 thus gained the ability for the mineralization of all isomeric monochloro- and bromobenzoates of the so-called lower pathway which, consequently, also allowed the mineralization of all monochlorobiphenyls and a number of di- and trichlorobiphenyls, thus preventing the accumulation of halobenzoates and of catabolites thereof. LB400 and KF707 also grow with the two commercial PCB formulations, Aroclor 1221 and Aroclor 1232, as the sole carbon and energy sources, but not with higher halogenated PCB mixtures, similar to the already published strain RW112. Repeated exposition of the modified LB400 to short pulses of UV light, over a prolonged period of time, allowed the isolation of a derivative of LB400, termed RW118, capable of growth with Aroclor 1016 still containing only traces of biphenyl, and in co-culture with modified KF707 termed RW120, and modified H850 (RW112) with Aroclor 1242, the commercial mixture already void of biphenyl and monochlorobiphenyls.
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Affiliation(s)
- Verónica Hernández-Sánchez
- Department of Environmental Protection, Experimental Station of the Zaidín, Spanish High Council for Scientific Research Granada, Spain
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31
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Payne RB, Fagervold SK, May HD, Sowers KR. Remediation of Polychlorinated Biphenyl Impacted Sediment by Concurrent Bioaugmentation with Anaerobic Halorespiring and Aerobic Degrading Bacteria. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:3807-15. [PMID: 23463900 PMCID: PMC3671860 DOI: 10.1021/es304372t] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Affiliation(s)
- Rayford B. Payne
- Institute of Marine and Environmental
Technology, Department of Marine Biotechnology, University of Maryland Baltimore County, Baltimore, Maryland 21202,
United States
| | - Sonja K. Fagervold
- UPMC Univ
Paris 06, UMR 8882, LECOB, Observatoire Océanologique, F-66650, Banyuls/Mer, France
| | - Harold D. May
- Marine Biomedicine and Environmental
Science Center, Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, South
Carolina 29412, United States
| | - Kevin R. Sowers
- Institute of Marine and Environmental
Technology, Department of Marine Biotechnology, University of Maryland Baltimore County, Baltimore, Maryland 21202,
United States
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Xiong F, Shuai JJ, Jin XF, Zhang J, Sun J, Peng RH, Yao QH, Xiong AS. Expression and characterization of a recombinant 2,3-dihydroxybiphenyl-1,2-dioxygenase from Pseudomonas. Mol Cell Toxicol 2013. [DOI: 10.1007/s13273-012-0046-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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33
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Colbert CL, Agar NYR, Kumar P, Chakko MN, Sinha SC, Powlowski JB, Eltis LD, Bolin JT. Structural characterization of Pandoraea pnomenusa B-356 biphenyl dioxygenase reveals features of potent polychlorinated biphenyl-degrading enzymes. PLoS One 2013; 8:e52550. [PMID: 23308114 PMCID: PMC3536784 DOI: 10.1371/journal.pone.0052550] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2012] [Accepted: 11/19/2012] [Indexed: 11/19/2022] Open
Abstract
The oxidative degradation of biphenyl and polychlorinated biphenyls (PCBs) is initiated in Pandoraea pnomenusa B-356 by biphenyl dioxygenase (BPDO(B356)). BPDO(B356), a heterohexameric (αβ)(3) Rieske oxygenase (RO), catalyzes the insertion of dioxygen with stereo- and regioselectivity at the 2,3-carbons of biphenyl, and can transform a broad spectrum of PCB congeners. Here we present the X-ray crystal structures of BPDO(B356) with and without its substrate biphenyl 1.6-Å resolution for both structures. In both cases, the Fe(II) has five ligands in a square pyramidal configuration: H233 Nε2, H239 Nε2, D386 Oδ1 and Oδ2, and a single water molecule. Analysis of the active sites of BPDO(B356) and related ROs revealed structural features that likely contribute to the superior PCB-degrading ability of certain BPDOs. First, the active site cavity readily accommodates biphenyl with minimal conformational rearrangement. Second, M231 was predicted to sterically interfere with binding of some PCBs, and substitution of this residue yielded variants that transform 2,2'-dichlorobiphenyl more effectively. Third, in addition to the volume and shape of the active site, residues at the active site entrance also apparently influence substrate preference. Finally, comparison of the conformation of the active site entrance loop among ROs provides a basis for a structure-based classification consistent with a phylogeny derived from amino acid sequence alignments.
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Affiliation(s)
- Christopher L Colbert
- Department of Chemistry and Biochemistry, North Dakota State University, Fargo, ND, USA.
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Booth SC, George IFS, Zannoni D, Cappelletti M, Duggan GE, Ceri H, Turner RJ. Effect of aluminium and copper on biofilm development of Pseudomonas pseudoalcaligenes KF707 and P. fluorescens as a function of different media compositions. Metallomics 2013; 5:723-35. [DOI: 10.1039/c3mt20240b] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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35
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Uhlik O, Musilova L, Ridl J, Hroudova M, Vlcek C, Koubek J, Holeckova M, Mackova M, Macek T. Plant secondary metabolite-induced shifts in bacterial community structure and degradative ability in contaminated soil. Appl Microbiol Biotechnol 2012; 97:9245-56. [PMID: 23250224 DOI: 10.1007/s00253-012-4627-6] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Revised: 11/26/2012] [Accepted: 11/28/2012] [Indexed: 01/22/2023]
Abstract
The aim of the study was to investigate how selected natural compounds (naringin, caffeic acid, and limonene) induce shifts in both bacterial community structure and degradative activity in long-term polychlorinated biphenyl (PCB)-contaminated soil and how these changes correlate with changes in chlorobiphenyl degradation capacity. In order to address this issue, we have integrated analytical methods of determining PCB degradation with pyrosequencing of 16S rRNA gene tag-encoded amplicons and DNA-stable isotope probing (SIP). Our model system was set in laboratory microcosms with PCB-contaminated soil, which was enriched for 8 weeks with the suspensions of flavonoid naringin, terpene limonene, and phenolic caffeic acid. Our results show that application of selected plant secondary metabolites resulted in bacterial community structure far different from the control one (no natural compound amendment). The community in soil treated with caffeic acid is almost solely represented by Proteobacteria, Acidobacteria, and Verrucomicrobia (together over 99 %). Treatment with naringin resulted in an enrichment of Firmicutes to the exclusion of Acidobacteria and Verrucomicrobia. SIP was applied in order to identify populations actively participating in 4-chlorobiphenyl catabolism. We observed that naringin and limonene in soil foster mainly populations of Hydrogenophaga spp., caffeic acid Burkholderia spp. and Pseudoxanthomonas spp. None of these populations were detected among 4-chlorobiphenyl utilizers in non-amended soil. Similarly, the degradation of individual PCB congeners was influenced by the addition of different plant compounds. Residual content of PCBs was lowest after treating the soil with naringin. Addition of caffeic acid resulted in comparable decrease of total PCBs with non-amended soil; however, higher substituted congeners were more degraded after caffeic acid treatment compared to all other treatments. Finally, it appears that plant secondary metabolites have a strong effect on the bacterial community structure, activity, and associated degradative ability.
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Affiliation(s)
- Ondrej Uhlik
- Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, Institute of Chemical Technology Prague, Technicka 3, 166 28, Prague 6, Czech Republic,
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36
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Li A, Qu YY, Pi WQ, Zhou JT, Gai ZH, Xu P. Metabolic characterization and genes for the conversion of biphenyl in Dyella ginsengisoli LA-4. Biotechnol Bioeng 2011; 109:609-13. [PMID: 21928338 DOI: 10.1002/bit.23333] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2011] [Revised: 09/04/2011] [Accepted: 09/07/2011] [Indexed: 11/10/2022]
Abstract
A complete bph gene cluster (bphLA-4) containing 12,186 bp was amplified from Dyella ginsengisoli LA-4. The bphLA-4 was composed of bphABCXD, and an additional gene encoding a meta-fission product hydrolase was located in the bphX region. BphLA-4 was independently transcribed by the two operons, bphA1A2orf1A3A4BCX0 and bphX1orf2X2X3D, and significantly differed from bphKF707. Both benzoate and catechol induced the expression of both operons. 2-Hydroxypenta-2,4-dienoate was identified as the intermediate of the biphenyl degradation by strain LA-4. This finding suggested that there existed a novel lower pathway of biphenyl degradation in strain LA-4.
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Affiliation(s)
- Ang Li
- State Key Laboratory of Fine Chemicals, Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, People's Republic of China
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37
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Expression in Escherichia coli of biphenyl 2,3-dioxygenase genes from a Gram-positive polychlorinated biphenyl degrader, Rhodococcus jostii RHA1. Biosci Biotechnol Biochem 2011; 75:26-33. [PMID: 21228494 DOI: 10.1271/bbb.100452] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Rhodococcus jostii RHA1 is a polychlorinated biphenyl degrader. Multi-component biphenyl 2,3-dioxygenase (BphA) genes of RHA1 encode large and small subunits of oxygenase component and ferredoxin and reductase components. They did not express enzyme activity in Escherichia coli. To obtain BphA activity in E. coli, hybrid BphA gene derivatives were constructed by replacing ferredoxin and/or reductase component genes of RHA1 with those of Pseudomonas pseudoalcaligenes KF707. The results obtained indicate a lack of catalytic activity of the RHA1 ferredoxin component gene, bphAc in E. coli. To determine the cause of inability of RHA1 bphAc to express in E. coli, the bphAc gene was introduced into Rosetta (DE3) pLacI, which has extra tRNA genes for rare codons in E. coli. The resulting strain abundantly produced the bphAc product, and showed activity. These results suggest that codon usage bias is involved in inability of RHA1 bphAc to express its catalytic activity in E. coli.
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38
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Development of a strain for efficient degradation of polychlorinated biphenyls by patchwork assembly of degradation pathways. J Biosci Bioeng 2011; 111:437-42. [DOI: 10.1016/j.jbiosc.2010.12.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2010] [Revised: 11/15/2010] [Accepted: 12/01/2010] [Indexed: 11/21/2022]
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39
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Khomenkov VG, Shevelev AB, Zhukov VG, Zagustina NA, Bezborodov AM, Popov VO. Organization of metabolic pathways and molecular-genetic mechanisms of xenobiotic degradation in microorganisms: A review. APPL BIOCHEM MICRO+ 2011. [DOI: 10.1134/s0003683808020014] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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40
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Tremaroli V, Fedi S, Tamburini S, Viti C, Tatti E, Ceri H, Turner RJ, Zannoni D. A histidine-kinase cheA gene of Pseudomonas pseudoalcaligens KF707 not only has a key role in chemotaxis but also affects biofilm formation and cell metabolism. BIOFOULING 2011; 27:33-46. [PMID: 21108067 DOI: 10.1080/08927014.2010.537099] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A histidine-kinase cheA gene in Pseudomonas pseudoalcaligenes KF707 plays a central role in the regulation of metabolic responses as well as in chemotaxis. Non-chemotactic mutants harboring insertions into the cheA gene were screened for their ability to form biofilms in the Calgary biofilm device. Notably, ≥95% decrease in the number of cells attached to the polystyrene surface was observed in cheA mutants compared to the KF707 wild-type biofilm phenotype. The ability to form mature biofilms was restored to wild-type levels, providing functional copies of the KF707 cheA gene to the mutants. In addition, phenotype micro-arrays and proteomic analyses revealed that several basic metabolic activities and a few periplasmic binding proteins of cheA mutant cells differed compared to those of wild-type cells. These results are interpreted as evidence of a strong integration between chemotactic and metabolic pathways in the process of biofilm development by P. pseudoalcaligenes KF707.
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Affiliation(s)
- V Tremaroli
- Department of Biological Sciences & Biofilm Research Group, University of Calgary, Calgary, Alberta, Canada
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41
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Tremaroli V, Vacchi Suzzi C, Fedi S, Ceri H, Zannoni D, Turner RJ. Tolerance of Pseudomonas pseudoalcaligenes KF707 to metals, polychlorobiphenyls and chlorobenzoates: effects on chemotaxis-, biofilm- and planktonic-grown cells. FEMS Microbiol Ecol 2010; 74:291-301. [PMID: 20846140 DOI: 10.1111/j.1574-6941.2010.00965.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Pseudomonas pseudoalcaligenes KF707 is a polychlorinated biphenyls (PCBs) degrader, also tolerant to several toxic metals and metalloids. The work presented here examines for the first time the chemotactic response of P. pseudoalcaligenes KF707 to biphenyl and intermediates of the PCB biodegradation pathway in the presence and absence of metals. Chemotaxis analyses showed that biphenyl, benzoic acid and chlorobenzoic acids acted as chemoattractants for KF707 cells and that metal cations such as Ni(2+) and Cu(2+) strongly affected the chemotactic response. Toxicity profiles of various metals on KF707 cells grown on succinate or biphenyl as planktonic and biofilm were determined both in the presence and in the absence of PCBs. Notably, KF707 cells from both biofilms and planktonic cultures were tolerant to high amounts (up to 0.5 g L(-1)) of Aroclor 1242, a commercial mixture of PCBs. Together, the data show that KF707 cells are chemotactic and can form a biofilm in the presence of Aroclor 1242 and specific metals. These findings provide new perspectives on the effectiveness of using PCB-degrading bacterial strains in bioremediation strategies of metal-co-contaminated sites.
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Affiliation(s)
- Valentina Tremaroli
- Department of Biology, General Microbiology Unit, University of Bologna, Bologna, Italy
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42
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Suenaga H, Nonaka K, Fujihara H, Goto M, Furukawa K. Hybrid pseudomonads engineered by two-step homologous recombination acquire novel degradation abilities toward aromatics and polychlorinated biphenyls. Appl Microbiol Biotechnol 2010; 88:915-23. [PMID: 20809076 DOI: 10.1007/s00253-010-2840-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2010] [Revised: 08/11/2010] [Accepted: 08/12/2010] [Indexed: 10/19/2022]
Abstract
Pseudomonas pseudoalcaligenes KF707 possesses a chromosomally encoded bph gene cluster responsible for the catabolism of biphenyl and polychlorinated biphenyls. Previously, we constructed chimeric versions of the bphA1 gene, which encodes a large subunit of biphenyl dioxygenase, by using DNA shuffling between bphA1 genes from P. pseudoalcaligenes KF707 and Burkholderia xenovorans LB400. In this study, we demonstrate replacement of the bphA1 gene with chimeric bphA1 sequence within the chromosomal bph gene cluster by two-step homologous recombination. Notably, some of the hybrid strains acquired enhanced and/or expanded degradation capabilities for specific aromatic compounds, including single aromatic hydrocarbons and polychlorinated biphenyls.
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Affiliation(s)
- Hikaru Suenaga
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba 305-8566, Japan.
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43
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Lakshminarasimhan M, Madzelan P, Nan R, Milkovic NM, Wilson MA. Evolution of new enzymatic function by structural modulation of cysteine reactivity in Pseudomonas fluorescens isocyanide hydratase. J Biol Chem 2010; 285:29651-61. [PMID: 20630867 DOI: 10.1074/jbc.m110.147934] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Isocyanide (formerly isonitrile) hydratase (EC 4.2.1.103) is an enzyme of the DJ-1 superfamily that hydrates isocyanides to yield the corresponding N-formamide. In order to understand the structural basis for isocyanide hydratase (ICH) catalysis, we determined the crystal structures of wild-type and several site-directed mutants of Pseudomonas fluorescens ICH at resolutions ranging from 1.0 to 1.9 Å. We also developed a simple UV-visible spectrophotometric assay for ICH activity using 2-naphthyl isocyanide as a substrate. ICH contains a highly conserved cysteine residue (Cys(101)) that is required for catalysis and interacts with Asp(17), Thr(102), and an ordered water molecule in the active site. Asp(17) has carboxylic acid bond lengths that are consistent with protonation, and we propose that it activates the ordered water molecule to hydrate organic isocyanides. In contrast to Cys(101) and Asp(17), Thr(102) is tolerant of mutagenesis, and the T102V mutation results in a substrate-inhibited enzyme. Although ICH is similar to human DJ-1 (1.6 Å C-α root mean square deviation), structural differences in the vicinity of Cys(101) disfavor the facile oxidation of this residue that is functionally important in human DJ-1 but would be detrimental to ICH activity. The ICH active site region also exhibits surprising conformational plasticity and samples two distinct conformations in the crystal. ICH represents a previously uncharacterized clade of the DJ-1 superfamily that possesses a novel enzymatic activity, demonstrating that the DJ-1 core fold can evolve diverse functions by subtle modulation of the environment of a conserved, reactive cysteine residue.
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Affiliation(s)
- Mahadevan Lakshminarasimhan
- Department of Biochemistry and Redox Biology Center, University of Nebraska, Lincoln, Nebraska 68588-0664, USA
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44
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Identification and Analysis of Polychlorinated Biphenyls (PCBs)-Biodegrading Bacterial Strains in Shanghai. Curr Microbiol 2010; 61:477-83. [DOI: 10.1007/s00284-010-9641-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2010] [Accepted: 03/16/2010] [Indexed: 10/19/2022]
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45
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Pacios LF, Campos VM, Merino I, Gómez L. Structures and thermodynamics of biphenyl dihydrodiol stereoisomers and their metabolites in the enzymatic degradation of arene xenobiotics. J Comput Chem 2009; 30:2420-32. [PMID: 19360792 DOI: 10.1002/jcc.21248] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
A key step in the metabolic degradation of biphenyl xenobiotics is catechol formation upon dehydrogenation of cis- and trans-dihydrodiols in prokaryotic and eukaryotic pathways, respectively. Structure and thermodynamics of stereoisomers of cis-, trans-2,3-biphenyl-dihydrodiols (I) and their dehydrogenation products (hydroxyketones, II), as well as final catechol (2,3-biphenyldiol, III) are studied by means of ab initio MP2/6-311++G(2df,2p)//MP2/6-311G(d,p) calculations. Formation of stereoisomers I and II is exothermic and endergonic, whereas III is enthalpically and entropically driven. Dehydrogenations are endothermic (DeltaHR0 approximately 1.5-4 kcal mol(-1)) and exergonic (DeltaGR0 approximately -5 to -7.5 kcal mol(-1)) without noticeable differences between cis and trans pathways, although the same keto stereoisomer II-(2S) is found to be the more favored product from both cis- and trans-I. The final II --> III tautomerization is thermodynamically enhanced (DeltaHR0 approximately -27, DeltaGR0 approximately -28 kcal mol(-1)) but the process is shown to have a large activation energy if it had to occur via unimolecular path. Although this tautomerization is generally assumed to be a nonenzymatic process as it involves rearomatization of an oxygenated ring, proton transfer with an anionic intermediate might be a more probable process.
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Affiliation(s)
- Luis F Pacios
- Unidad de Química y Bioquímica, Departamento de Biotecnología, E. T. S. Ingenieros de Montes, Universidad Politécnica de Madrid, 28040 Madrid, Spain.
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46
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DNA-stable isotope probing integrated with metagenomics for retrieval of biphenyl dioxygenase genes from polychlorinated biphenyl-contaminated river sediment. Appl Environ Microbiol 2009; 75:5501-6. [PMID: 19648381 DOI: 10.1128/aem.00121-09] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Stable isotope probing with [(13)C]biphenyl was used to explore the genetic properties of indigenous bacteria able to grow on biphenyl in PCB-contaminated River Raisin sediment. A bacterial 16S rRNA gene clone library generated from [(13)C]DNA after a 14-day incubation with [(13)C]biphenyl revealed the dominant organisms to be members of the genera Achromobacter and Pseudomonas. A library built from PCR amplification of genes for aromatic-ring-hydroxylating dioxygenases from the [(13)C]DNA fraction revealed two sequence groups similar to bphA (encoding biphenyl dioxygenase) of Comamonas testosteroni strain B-356 and of Rhodococcus sp. RHA1. A library of 1,568 cosmid clones was produced from the [(13)C]DNA fraction. A 31.8-kb cosmid clone, detected by aromatic dioxygenase primers, contained genes of biphenyl dioxygenase subunits bphAE, while the rest of the clone's sequence was similar to that of an unknown member of the Gammaproteobacteria. A discrepancy in G+C content near the bphAE genes implies their recent acquisition, possibly by horizontal transfer. The biphenyl dioxygenase from the cosmid clone oxidized biphenyl and unsubstituted and para-only-substituted rings of polychlorinated biphenyl (PCB) congeners. A DNA-stable isotope probing-based cosmid library enabled the retrieval of functional genes from an uncultivated organism capable of PCB metabolism and suggest dispersed dioxygenase gene organization in nature.
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Tremaroli V, Workentine ML, Weljie AM, Vogel HJ, Ceri H, Viti C, Tatti E, Zhang P, Hynes AP, Turner RJ, Zannoni D. Metabolomic investigation of the bacterial response to a metal challenge. Appl Environ Microbiol 2009; 75:719-28. [PMID: 19047385 PMCID: PMC2632130 DOI: 10.1128/aem.01771-08] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2008] [Accepted: 11/22/2008] [Indexed: 11/20/2022] Open
Abstract
Pseudomonas pseudoalcaligenes KF707 is naturally resistant to the toxic metalloid tellurite, but the mechanisms of resistance are not known. In this study we report the isolation of a KF707 mutant (T5) with hyperresistance to tellurite. In order to characterize the bacterial response and the pathways leading to tolerance, we utilized Phenotype MicroArray technology (Biolog) and a metabolomic technique based on nuclear magnetic resonance spectroscopy. The physiological states of KF707 wild-type and T5 cells exposed to tellurite were also compared in terms of viability and reduced thiol content. Our analyses showed an extensive change in metabolism upon the addition of tellurite to KF707 cultures as well as different responses when the wild-type and T5 strains were compared. Even in the absence of tellurite, T5 cells displayed a "poised" physiological status, primed for tellurite exposure and characterized by altered intracellular levels of glutathione, branched-chain amino acids, and betaine, along with increased resistance to other toxic metals and metabolic inhibitors. We conclude that hyperresistance to tellurite in P. pseudoalcaligenes KF707 is correlated with the induction of the oxidative stress response, resistance to membrane perturbation, and reconfiguration of cellular metabolism.
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Li A, Qu Y, Zhou J, Gou M. Isolation and characteristics of a novel biphenyl-degrading bacterial strain, Dyella ginsengisoli LA-4. J Environ Sci (China) 2009; 21:211-217. [PMID: 19402424 DOI: 10.1016/s1001-0742(08)62253-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
A novel biphenyl-degrading bacterial strain LA-4 was isolated from activated sludge. It was identified as Dyella ginsengisoli according to phylogenetic similarity of 16S rRNA gene sequence. This isolate could utilize biphenyl as sole source of carbon and energy, which degraded over 95 mg/L biphenyl within 36 h. The major metabolites formed from biphenyl, such as 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoic acid (HOPDA) and benzoic acid, were identified by LC-MS. The crude cell extract of strain LA-4 exhibited the activity of 2,3-dihydroxybiphenyl 1,2-dioxygenase (2,3-DHBD) and the kinetic parameters K(m) was 26.48 micromol/L and V(max) was 8.12 U/mg protein. A conserved region of the biphenyl dioxygenase gene bphA1 of strain LA-4 was amplified by PCR and confirmed by DNA sequencing.
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Affiliation(s)
- Ang Li
- School of Environmental and Biological Science and Technology, Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education, China), Dalian University of Technology, Dalian 116024, China.
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Friemann R, Lee K, Brown EN, Gibson DT, Eklund H, Ramaswamy S. Structures of the multicomponent Rieske non-heme iron toluene 2,3-dioxygenase enzyme system. ACTA CRYSTALLOGRAPHICA. SECTION D, BIOLOGICAL CRYSTALLOGRAPHY 2009; 65:24-33. [PMID: 19153463 PMCID: PMC2628974 DOI: 10.1107/s0907444908036524] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/28/2008] [Accepted: 11/06/2008] [Indexed: 11/14/2022]
Abstract
Bacterial Rieske non-heme iron oxygenases catalyze the initial hydroxylation of aromatic hydrocarbon substrates. The structures of all three components of one such system, the toluene 2,3-dioxygenase system, have now been determined. This system consists of a reductase, a ferredoxin and a terminal dioxygenase. The dioxygenase, which was cocrystallized with toluene, is a heterohexamer containing a catalytic and a structural subunit. The catalytic subunit contains a Rieske [2Fe-2S] cluster and mononuclear iron at the active site. This iron is not strongly bound and is easily removed during enzyme purification. The structures of the enzyme with and without mononuclear iron demonstrate that part of the structure is flexible in the absence of iron. The orientation of the toluene substrate in the active site is consistent with the regiospecificity of oxygen incorporation seen in the product formed. The ferredoxin is Rieske type and contains a [2Fe-2S] cluster close to the protein surface. The reductase belongs to the glutathione reductase family of flavoenzymes and consists of three domains: an FAD-binding domain, an NADH-binding domain and a C-terminal domain. A model for electron transfer from NADH via FAD in the reductase and the ferredoxin to the terminal active-site mononuclear iron of the dioxygenase is proposed.
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Affiliation(s)
- Rosmarie Friemann
- Department of Molecular Biology, Swedish University of Agricultural Sciences, Box 590, 751 24 Uppsala, Sweden
| | - Kyoung Lee
- Department of Microbiology, Changwon National University, Changwon, Kyoungnam 641-773, Republic of Korea
- Department of Microbiology, The University of Iowa, Iowa City, Iowa 52242, USA
| | - Eric N. Brown
- Department of Biochemistry, The University of Iowa, Iowa City, Iowa 52242, USA
| | - David T. Gibson
- Department of Microbiology, The University of Iowa, Iowa City, Iowa 52242, USA
| | - Hans Eklund
- Department of Molecular Biology, Swedish University of Agricultural Sciences, Box 590, 751 24 Uppsala, Sweden
| | - S. Ramaswamy
- Department of Biochemistry, The University of Iowa, Iowa City, Iowa 52242, USA
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