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Hassan HA, D Enza M, Armengaud J, Pieper DH. Biochemical and genetic characterization comparison of four extradiol dioxygenases in Rhizorhabdus wittichii RW1. Appl Microbiol Biotechnol 2022; 106:5539-5550. [PMID: 35906995 DOI: 10.1007/s00253-022-12099-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 07/20/2022] [Accepted: 07/22/2022] [Indexed: 11/26/2022]
Abstract
Rhizorhabdus (previously Sphingomonas) wittichii RW1 uses a diverse array of aromatic organic compounds as energy and carbon sources, including some extremely recalcitrant compounds such as dibenzo-p-dioxin and dibenzofuran. Extradiol dioxygenases play a key role in the metabolism of dibenzofuran (DBF), dibenzo-p-dioxin (DBD), PCBs, and various other aromatic compounds. In this study, a detailed kinetic analysis of four extradiol dioxygenases identified in R. wittichii RW1 (DbfB, Edo2, Edo3, and Edo4) showed all of them to be typical 2,3dihydroxybiphenyl (DHB) dioxygenases with DHB as preferred substrate (kcat/Km values of 0.13-188 (µM -1 s-1)) and only slightly lower activity against trihydroxybiphenyl (THB) whereas monocyclic substrates were, to different extents, poor substrates due to high km values. All extradiol dioxygenases analyzed were subject to mechanism-based inactivation by 2,2`,3-trihydroxybiphenylether (THBE) the intermediate of DBD degradation. However, Edo4 was superior as reflected by the relatively high partition ratio and the comparably low efficiency of inactivation. Significant differences were observed with respect to their inactivation by 3-chlorocatechol. The absence of any significant mechanism-based inactivation makes Edo3 a perfect candidate for being recruited for chlorobiphenyl degradation where inactivation of extradiol dioxygenases by this intermediate creates significant metabolic problems. KEY POINTS: • Characterization of additional extradiol dioxygenases encoded by RW1 • Identification of differences in 2,2`,3-trihydroxybiphenylether transformation • Identification of differences in inhibition by 3-chlorocatechol.
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Affiliation(s)
- Hamdy A Hassan
- Department of Environmental Biotechnology, Genetic Engineering and Biotechnology Research Institute, University of Sadat City, Sadat City 32897, Egypt.
- Biology Department, Science and Humanities College, Shaqra University, Al-Quwayiyah, 11726, Riyadh, Saudi Arabia.
| | - Marina D Enza
- Microbial Interactions and Processes Research Group, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Jean Armengaud
- Microbial Interactions and Processes Research Group, Helmholtz Centre for Infection Research, Braunschweig, Germany
- Université Paris-Saclay, CEA, INRAE, Département Médicaments Et Technologies Pour La Santé, Bagnols-sur-Cèze, France
| | - Dietmar H Pieper
- Microbial Interactions and Processes Research Group, Helmholtz Centre for Infection Research, Braunschweig, Germany
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Chen Z, Hu H, Xu P, Tang H. Soil bioremediation by Pseudomonas brassicacearum MPDS and its enzyme involved in degrading PAHs. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 813:152522. [PMID: 34953839 DOI: 10.1016/j.scitotenv.2021.152522] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 12/14/2021] [Accepted: 12/14/2021] [Indexed: 06/14/2023]
Abstract
Polycyclic aromatic hydrocarbons (PAHs) commonly coexist in contaminated sites, posing a significant threat to ecosystem. Strains that degrade a wide range of substrates play important roles in bioremediation of contaminated environment. In this study, we reveal that Pseudomonas brassicacearum MPDS was able to remove 31.1% naphthalene of 500 mg/kg from soil within 2 d, while its relative abundance decreased significantly on Day 20, indicating its applicable potential in soil remediation. In addition to naphthalene, dibenzofuran, dibenzothiophene, and fluorene as reported previously, strain MPDS is able to degrade carbazole, phenanthrene, pyrene, and 2-bromonaphthalene. Moreover, NahA from strain MPDS has multi-substrate catalytic capacities on naphthalene, dibenzofuran, dibenzothiophene, phenanthrene, and 2-bromonaphthalene into dihydrodiols, while converts fluorene and carbazole into monohydroxy compounds according to GC-MS analysis. This study provides further insights into the exploration of soil remediation by strain MPDS and the mining of enzymes involved in the degradation of PAHs.
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Affiliation(s)
- Zhengshi Chen
- State Key Laboratory of Microbial Metabolism, and School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China
| | - Haiyang Hu
- State Key Laboratory of Microbial Metabolism, and School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China
| | - Ping Xu
- State Key Laboratory of Microbial Metabolism, and School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China
| | - Hongzhi Tang
- State Key Laboratory of Microbial Metabolism, and School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China.
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Ghosh P, Mukherji S. Environmental contamination by heterocyclic Polynuclear aromatic hydrocarbons and their microbial degradation. BIORESOURCE TECHNOLOGY 2021; 341:125860. [PMID: 34614557 DOI: 10.1016/j.biortech.2021.125860] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 08/23/2021] [Accepted: 08/25/2021] [Indexed: 06/13/2023]
Abstract
Heterocyclic polynuclear aromatic hydrocarbons (PAHs) have been detected in all environmental matrices at few ppb to several ppm concentrations and they are characterized by high polarity. Some heterocyclic PAHs are mutagenic and carcinogenic to humans and various organisms. Despite being potent environmental pollutants, these compounds have received less attention. This paper focuses on the sources and occurrence of these compounds and their microbial degradation using diverse species of bacteria, fungi, and algae. Complete removal of 1.8 to 2614 mg/L of nitrogen heterocyclic PAH (PANH), 0.27 to 184 mg/L of sulfur heterocyclic PAH (PASH), and 0.6 to 120 mg/L of oxygen heterocyclic PAH (PAOH) compounds by various microbial species was observed between 3 h and 18 days, 8 h to 6 days, and 4 h to 250 h, respectively under aerobic condition. Strategies for enhancing the removal of heterocyclic PAHs from aquatic systems are also discussed along with the challenges.
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Affiliation(s)
- Prasenjit Ghosh
- Environmental Science and Engineering Department (ESED), Indian Institute of Technology Bombay, Powai, Mumbai 400076, India; Department of Civil Engineering, NIT Tiruchirappalli, Tiruchirappalli, Tamil Nadu 620015, India
| | - Suparna Mukherji
- Environmental Science and Engineering Department (ESED), Indian Institute of Technology Bombay, Powai, Mumbai 400076, India.
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Separate Upper Pathway Ring Cleavage Dioxygenases Are Required for Growth of Sphingomonas wittichii Strain RW1 on Dibenzofuran and Dibenzo- p-Dioxin. Appl Environ Microbiol 2021; 87:AEM.02464-20. [PMID: 33741618 DOI: 10.1128/aem.02464-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 03/09/2021] [Indexed: 11/20/2022] Open
Abstract
Sphingomonas wittichii RW1 is one of a few strains known to grow on the related compounds dibenzofuran (DBF) and dibenzo-p-dioxin (DXN) as the sole source of carbon. Previous work by others (B. Happe, L. D. Eltis, H. Poth, R. Hedderich, and K. N. Timmis, J Bacteriol 175:7313-7320, 1993, https://doi.org/10.1128/jb.175.22.7313-7320.1993) showed that purified DbfB had significant ring cleavage activity against the DBF metabolite trihydroxybiphenyl but little activity against the DXN metabolite trihydroxybiphenylether. We took a physiological approach to positively identify ring cleavage enzymes involved in the DBF and DXN pathways. Knockout of dbfB on the RW1 megaplasmid pSWIT02 results in a strain that grows slowly on DBF but normally on DXN, confirming that DbfB is not involved in DXN degradation. Knockout of SWIT3046 on the RW1 chromosome results in a strain that grows normally on DBF but that does not grow on DXN, demonstrating that SWIT3046 is required for DXN degradation. A double-knockout strain does not grow on either DBF or DXN, demonstrating that these are the only ring cleavage enzymes involved in RW1 DBF and DXN degradation. The replacement of dbfB by SWIT3046 results in a strain that grows normally (equal to the wild type) on both DBF and DXN, showing that promoter strength is important for SWIT3046 to take the place of DbfB in DBF degradation. Thus, both dbfB- and SWIT3046-encoded enzymes are involved in DBF degradation, but only the SWIT3046-encoded enzyme is involved in DXN degradation.IMPORTANCE S. wittichii RW1 has been the subject of numerous investigations, because it is one of only a few strains known to grow on DXN as the sole carbon and energy source. However, while the genome has been sequenced and several DBF pathway enzymes have been purified, there has been very little research using physiological techniques to precisely identify the genes and enzymes involved in the RW1 DBF and DXN catabolic pathways. Using knockout and gene replacement mutagenesis, our work identifies separate upper pathway ring cleavage enzymes involved in the related catabolic pathways for DBF and DXN degradation. The identification of a new enzyme involved in DXN biodegradation explains why the pathway of DBF degradation on the RW1 megaplasmid pSWIT02 is inefficient for DXN degradation. In addition, our work demonstrates that both plasmid- and chromosomally encoded enzymes are necessary for DXN degradation, suggesting that the DXN pathway has only recently evolved.
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Lopez-Echartea E, Suman J, Smrhova T, Ridl J, Pajer P, Strejcek M, Uhlik O. Genomic analysis of dibenzofuran-degrading Pseudomonas veronii strain Pvy reveals its biodegradative versatility. G3-GENES GENOMES GENETICS 2021; 11:6029021. [PMID: 33693598 PMCID: PMC8022969 DOI: 10.1093/g3journal/jkaa030] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 11/30/2020] [Indexed: 11/30/2022]
Abstract
Certain industrial chemicals accumulate in the environment due to their recalcitrant properties. Bioremediation uses the capability of some environmental bacteria to break down these chemicals and attenuate the pollution. One such bacterial strain, designated Pvy, was isolated from sediment samples from a lagoon in Romania located near an oil refinery due to its capacity to degrade dibenzofuran (DF). The genome sequence of the Pvy strain was obtained using an Oxford Nanopore MiniION platform. According to the consensus 16S rRNA gene sequence that was compiled from six 16S rRNA gene copies contained in the genome and orthologous average nucleotide identity (OrthoANI) calculation, the Pvy strain was identified as Pseudomonas veronii, which confirmed the identification obtained with the aid of MALDI-TOF mass spectrometry and MALDI BioTyper. The genome was analyzed with respect to enzymes responsible for the overall biodegradative versatility of the strain. The Pvy strain was able to derive carbon from naphthalene (NP) and several aromatic compounds of natural origin, including salicylic, protocatechuic, p-hydroxybenzoic, trans-cinnamic, vanillic, and indoleacetic acids or vanillin, and was shown to degrade but not utilize DF. In total seven loci were found in the Pvy genome, which enables the strain to participate in the degradation of these aromatic compounds. Our experimental data also indicate that the transcription of the NP-dioxygenase α-subunit gene (ndoB), carried by the plasmid of the Pvy strain, is inducible by DF. These features make the Pvy strain a potential candidate for various bioremediation applications.
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Affiliation(s)
- Eglantina Lopez-Echartea
- Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, University of Chemistry and Technology, Prague, Technicka 3, 166 28 Prague 6, Czech Republic
| | - Jachym Suman
- Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, University of Chemistry and Technology, Prague, Technicka 3, 166 28 Prague 6, Czech Republic
| | - Tereza Smrhova
- Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, University of Chemistry and Technology, Prague, Technicka 3, 166 28 Prague 6, Czech Republic
| | - Jakub Ridl
- Department of Genomics and Bioinformatics, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, Videnska 1083, 142 40 Prague, Czech Republic.,Division of Animal Evolutionary Biology, Department of Zoology, Faculty of Science, Charles University in Prague, Vinicna 7, 128 44 Prague, Czech Republic
| | - Petr Pajer
- Military Health Institute, Ministry of Defence of the Czech Republic, U Vojenske nemocnice 1200, 169 02 Prague 6, Czech Republic
| | - Michal Strejcek
- Department of Biochemistry and Microbiology, Faculty of Food and Biochemical Technology, University of Chemistry and Technology, Prague, Technicka 3, 166 28 Prague 6, 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 6, Czech Republic
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Saibu S, Adebusoye SA, Oyetibo GO. Aerobic bacterial transformation and biodegradation of dioxins: a review. BIORESOUR BIOPROCESS 2020. [DOI: 10.1186/s40643-020-0294-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
AbstractWaste generation tends to surge in quantum as the population and living conditions grow. A group of structurally related chemicals of dibenzofurans and dibenzo-p-dioxins including their chlorinated congeners collectively known as dioxins are among the most lethal environmental pollutants formed during different anthropogenic activities. Removal of dioxins from the environment is challenging due to their persistence, recalcitrance to biodegradation, and prevalent nature. Dioxin elimination through the biological approach is considered both economically and environmentally as a better substitute to physicochemical conventional approaches. Bacterial aerobic degradation of these compounds is through two major catabolic routes: lateral and angular dioxygenation pathways. Information on the diversity of bacteria with aerobic dioxin degradation capability has accumulated over the years and efforts have been made to harness this fundamental knowledge to cleanup dioxin-polluted soils. This paper covers the previous decades and recent developments on bacterial diversity and aerobic bacterial transformation, degradation, and bioremediation of dioxins in contaminated systems.
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Miyazawa D, Thanh LTH, Tani A, Shintani M, Loc NH, Hatta T, Kimbara K. Isolation and Characterization of Genes Responsible for Naphthalene Degradation from Thermophilic Naphthalene Degrader, Geobacillus sp. JF8. Microorganisms 2019; 8:microorganisms8010044. [PMID: 31878343 PMCID: PMC7023095 DOI: 10.3390/microorganisms8010044] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Revised: 12/18/2019] [Accepted: 12/19/2019] [Indexed: 11/26/2022] Open
Abstract
Geobacillus sp. JF8 is a thermophilic biphenyl and naphthalene degrader. To identify the naphthalene degradation genes, cis-naphthalene dihydrodiol dehydrogenase was purified from naphthalene-grown cells, and its N-terminal amino acid sequence was determined. Using a DNA probe encoding the N-terminal region of the dehydrogenase, a 10-kb DNA fragment was isolated. Upstream of nahB, a gene for dehydrogenase, there were two open reading frames which were designated as nahAc and nahAd, respectively. The products of nahAc and nahAd were predicted to be alpha and beta subunit of ring-hydroxylating dioxygenases, respectively. Phylogenetic analysis of amino acid sequences of NahB indicated that it did not belong to the cis-dihydrodiol dehydrogenase group that includes those of classical naphthalene degradation pathways. Downstream of nahB, four open reading frames were found, and their products were predicted as meta-cleavage product hydrolase, monooxygenase, dehydrogenase, and gentisate 1,2-dioxygenase, respectively. A reverse transcriptase-PCR analysis showed that transcription of nahAcAd was induced by naphthalene. These findings indicate that we successfully identified genes involved in the upper pathway of naphthalene degradation from a thermophilic bacterium.
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Affiliation(s)
- Daisuke Miyazawa
- Institute of Plant Science and Resources, Okayama University, 2-20-1 Chuo, Kurashiki, Okayama 710-0046, Japan; (D.M.); (A.T.)
| | - Le Thi Ha Thanh
- Department of Environment and Energy System, Graduate School of Science and Technology, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu, Shizuoka 432-8011, Japan;
- Institute of Bioactive Compounds, University of Sciences, Hue University, Hue, Thua Thien Hue 530000, Vietnam;
| | - Akio Tani
- Institute of Plant Science and Resources, Okayama University, 2-20-1 Chuo, Kurashiki, Okayama 710-0046, Japan; (D.M.); (A.T.)
| | - Masaki Shintani
- Department of Bioscience, Graduate School of Science and Technology, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu, Shizuoka 432-8561, Japan
- Department of Engineering, Graduate School of Integrated Science and Technology, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu, Shizuoka 432-8561, Japan
- Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, Shizuoka 422-8529, Japan
- Correspondence: (M.S.); (K.K.); Tel.: +81-53-478-1181 (M.S.); +81-53-478-1170 (K.K.)
| | - Nguyen Hoang Loc
- Institute of Bioactive Compounds, University of Sciences, Hue University, Hue, Thua Thien Hue 530000, Vietnam;
| | - Takashi Hatta
- Department of Biomedical Engineering, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama 703-8232, Japan;
| | - Kazuhide Kimbara
- Department of Environment and Energy System, Graduate School of Science and Technology, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu, Shizuoka 432-8011, Japan;
- Department of Engineering, Graduate School of Integrated Science and Technology, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu, Shizuoka 432-8561, Japan
- Correspondence: (M.S.); (K.K.); Tel.: +81-53-478-1181 (M.S.); +81-53-478-1170 (K.K.)
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Hanano A, Ammouneh H, Almousally I, Alorr A, Shaban M, Alnaser AA, Ghanem I. Traceability of polychlorinated dibenzo-dioxins/furans pollutants in soil and their ecotoxicological effects on genetics, functions and composition of bacterial community. CHEMOSPHERE 2014; 108:326-333. [PMID: 24534156 DOI: 10.1016/j.chemosphere.2014.01.061] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Revised: 01/23/2014] [Accepted: 01/26/2014] [Indexed: 06/03/2023]
Abstract
Dioxins (PCDD/Fs) are persistent organic pollutants. Their accumulation in soil is a crucial step in their transmission through the ecosystem. Traceability of dioxin in soil was evaluated in four sites A, B, C and D considered as potential industrial PCDD/Fs sources in Syria. Our results showed that the highest pollution with dioxin (⩾50 ppt) was found in site C (vicinity of Homs refinery). In parallel, analysis of physicochemical proprieties and bacterial density of soil samples were carried out. Bacterial density differed significantly among samples between 68×10(4) and 64×10(6) CFU g(-1)DW. Analysis of 16S rRNA encoding sequences showed that the genus Bacillus was the most abundant (74.7%) in all samples, followed by the genera Arthrobacter and Klebsiella with 5.2% and 4.7%, respectively. The genera Microbacterium, Pantoea, Pseudomonas, Enterobacter and Exiguobacterium formed between 2.1% and 2.6%. Cellulomonas, Kocuria, Lysinibacillus, Staphylococcus and Streptomyces were in a minority (0.5-1%). The bacterial richness and biodiversity, estimated by DMg and H' index, were highest in the heavily polluted site. Molecular screening for angular dioxygenase (AD α-subunit) and the cytochrome P450 (CYPBM3) genes, led to identification of 41 strains as AD-positive and 31 strains as CYPBM3-positive. RT-real-time PCR analysis showed a significant abundance of AD α-subunit transcript in the heavily dioxin-polluted soils, while the expression of CYPBM3 was highest in the moderately polluted soils. Our results illustrate the microbial diversity and functionality in soil exposed to dioxin pollution. Identification of dioxin-degrading bacteria from polluted sites should allow bioremediation to be carried out.
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Affiliation(s)
- Abdulsamie Hanano
- Department of Molecular Biology and Biotechnology, Atomic Energy Commission of Syria (AECS), B.P. Box 6091, Damascus, Syria.
| | - Hassan Ammouneh
- Department of Molecular Biology and Biotechnology, Atomic Energy Commission of Syria (AECS), B.P. Box 6091, Damascus, Syria
| | - Ibrahem Almousally
- Department of Molecular Biology and Biotechnology, Atomic Energy Commission of Syria (AECS), B.P. Box 6091, Damascus, Syria
| | - Abdulfattah Alorr
- Department of Molecular Biology and Biotechnology, Atomic Energy Commission of Syria (AECS), B.P. Box 6091, Damascus, Syria
| | - Mouhnad Shaban
- Department of Molecular Biology and Biotechnology, Atomic Energy Commission of Syria (AECS), B.P. Box 6091, Damascus, Syria
| | - Amer Abu Alnaser
- Department of Molecular Biology and Biotechnology, Atomic Energy Commission of Syria (AECS), B.P. Box 6091, Damascus, Syria
| | - Iyad Ghanem
- Department of Molecular Biology and Biotechnology, Atomic Energy Commission of Syria (AECS), B.P. Box 6091, Damascus, Syria
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A novel angular dioxygenase gene cluster encoding 3-phenoxybenzoate 1',2'-dioxygenase in Sphingobium wenxiniae JZ-1. Appl Environ Microbiol 2014; 80:3811-8. [PMID: 24747891 DOI: 10.1128/aem.00208-14] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Sphingobium wenxiniae JZ-1 utilizes a wide range of pyrethroids and their metabolic product, 3-phenoxybenzoate, as sources of carbon and energy. A mutant JZ-1 strain, MJZ-1, defective in the degradation of 3-phenoxybenzoate was obtained by successive streaking on LB agar. Comparison of the draft genomes of strains JZ-1 and MJZ-1 revealed that a 29,366-bp DNA fragment containing a putative angular dioxygenase gene cluster (pbaA1A2B) is missing in strain MJZ-1. PbaA1, PbaA2, and PbaB share 65%, 52%, and 10% identity with the corresponding α and β subunits and the ferredoxin component of dioxin dioxygenase from Sphingomonas wittichii RW1, respectively. Complementation of pbaA1A2B in strain MJZ-1 resulted in the active 3-phenoxybenzoate 1',2'-dioxygenase, but the enzyme activity in Escherichia coli was achieved only through the coexpression of pbaA1A2B and a glutathione reductase (GR)-type reductase gene, pbaC, indicating that the 3-phenoxybenzoate 1',2'-dioxygenase belongs to a type IV Rieske non-heme iron aromatic ring-hydroxylating oxygenase system consisting of a hetero-oligomeric oxygenase, a [2Fe-2S]-type ferredoxin, and a GR-type reductase. The pbaC gene is not located in the immediate vicinity of pbaA1A2B. 3-Phenoxybenzoate 1',2'-dioxygenase catalyzes the hydroxylation in the 1' and 2' positions of the benzene moiety of 3-phenoxybenzoate, yielding 3-hydroxybenzoate and catechol. Transcription of pbaA1A2B and pbaC was induced by 3-phenoxybenzoate, but the transcriptional level of pbaC was far less than that of pbaA1A2B, implying the possibility that PbaC may not be the only reductase that can physiologically transfer electrons to PbaA1A2B in strain JZ-1. Some GR-type reductases from other sphingomonad strains could also transfer electrons to PbaA1A2B, suggesting that PbaA1A2B has a low specificity for reductase.
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Penton CR, Johnson TA, Quensen JF, Iwai S, Cole JR, Tiedje JM. Functional genes to assess nitrogen cycling and aromatic hydrocarbon degradation: primers and processing matter. Front Microbiol 2013; 4:279. [PMID: 24062736 PMCID: PMC3775264 DOI: 10.3389/fmicb.2013.00279] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Accepted: 08/28/2013] [Indexed: 12/03/2022] Open
Abstract
Targeting sequencing to genes involved in key environmental processes, i.e., ecofunctional genes, provides an opportunity to sample nature's gene guilds to greater depth and help link community structure to process-level outcomes. Vastly different approaches have been implemented for sequence processing and, ultimately, for taxonomic placement of these gene reads. The overall quality of next generation sequence analysis of functional genes is dependent on multiple steps and assumptions of unknown diversity. To illustrate current issues surrounding amplicon read processing we provide examples for three ecofunctional gene groups. A combination of in silico, environmental and cultured strain sequences was used to test new primers targeting the dioxin and dibenzofuran degrading genes dxnA1, dbfA1, and carAa. The majority of obtained environmental sequences were classified into novel sequence clusters, illustrating the discovery value of the approach. For the nitrite reductase step in denitrification, the well-known nirK primers exhibited deficiencies in reference database coverage, illustrating the need to refine primer-binding sites and/or to design multiple primers, while nirS primers exhibited bias against five phyla. Amino acid-based OTU clustering of these two N-cycle genes from soil samples yielded only 114 unique nirK and 45 unique nirS genus-level groupings, likely a reflection of constricted primer coverage. Finally, supervised and non-supervised OTU analysis methods were compared using the nifH gene of nitrogen fixation, with generally similar outcomes, but the clustering (non-supervised) method yielded higher diversity estimates and stronger site-based differences. High throughput amplicon sequencing can provide inexpensive and rapid access to nature's related sequences by circumventing the culturing barrier, but each unique gene requires individual considerations in terms of primer design and sequence processing and classification.
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Affiliation(s)
- C Ryan Penton
- Department of Plant, Soil and Microbial Sciences, Center for Microbial Ecology, Michigan State University East Lansing, MI, USA
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Cloning of dfdA genes from Terrabacter sp. strain DBF63 encoding dibenzofuran 4,4a-dioxygenase and heterologous expression in Streptomyces lividans. Appl Microbiol Biotechnol 2012. [DOI: 10.1007/s00253-012-4565-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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12
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Peng P, Yang H, Jia R, Li L. Biodegradation of dioxin by a newly isolated Rhodococcus sp. with the involvement of self-transmissible plasmids. Appl Microbiol Biotechnol 2012; 97:5585-95. [DOI: 10.1007/s00253-012-4363-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Revised: 08/07/2012] [Accepted: 08/09/2012] [Indexed: 10/27/2022]
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13
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Suzuki Y, Nakamura M, Otsuka Y, Suzuki N, Ohyama K, Kawakami T, Sato K, Kajita S, Hishiyama S, Takahashi A, Katayama Y. Development of a highly sensitive assay for enzyme-mediated reductive degradation of polychlorinated dibenzo-p-dioxin. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2012; 31:1072-1075. [PMID: 22447772 DOI: 10.1002/etc.1775] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Revised: 10/12/2011] [Accepted: 01/02/2012] [Indexed: 05/31/2023]
Abstract
The degradation of 2-chloro-4,5-O-(4'-methyl-7', 8'-diphenyl)ether (CMDPE), an analog of 2,7-dichlorodibenzo-p-dioxin (2,7-DCDD), mediated by Geobacillus sp. UZO 3 cell-free extract was monitored. Ethyl acetate extracts of a complete reaction mixture incubated at 65°C for 18 h were analyzed either by thin layer chromatography (TLC) fractionation coupled with spectrometric detection or by gas chromatography-mass spectrometry (GC-MS). The reaction product 4-methylumbelliferone (4MU) was successfully isolated by TLC and visualized by a transilluminator at 450 nm. The 4MU, 4-chlorophenol, and reaction intermediate 6-chlorophenoxy-4-methylumbelliferone were all successfully detected by GC-MS. The presence of these compounds suggest that Geobacillus sp. UZO 3 cell-free extract also catalyzes the reductive cleavage of the diaryl ether bonds of CMDPE in a similar mechanism previously reported in 2,7-DCDD. In the present study, the authors describe a simple and highly sensitive fluorescent assay for a new dioxin degrading enzyme(s).
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Affiliation(s)
- Yuzo Suzuki
- Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo, Japan
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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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Suzuki Y, Nakamura M, Otsuka Y, Suzuki N, Ohyama K, Kawakami T, Sato K, Kajita S, Hishiyama S, Fujii T, Takahashi A, Katayama Y. Novel enzymatic activity of cell free extract from thermophilic Geobacillus sp. UZO 3 catalyzes reductive cleavage of diaryl ether bonds of 2,7-dichlorodibenzo-p-dioxin. CHEMOSPHERE 2011; 83:868-872. [PMID: 21435685 DOI: 10.1016/j.chemosphere.2011.02.068] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2010] [Revised: 01/30/2011] [Accepted: 02/27/2011] [Indexed: 05/30/2023]
Abstract
We characterized the ability of the cell free extract from polychlorinated dibenzo-p-dioxins degrading bacterium Geobacillus sp. UZO 3 to reduce even highly chlorinated dibenzo-p-dioxins such as octachlorodibenzo-p-dioxins in incineration fly ash. The degradation of 2,7-dichlorodibenzo-p-dioxin (2,7-DCDD) as a model dioxin catalyzed by the cell free extract from this strain implicates that the ether bonds of 2,7-DCDD molecule undergo reductive cleavage, since 4',5-dichloro-2-hydroxydiphenyl ether and 4-chlorophenol were detected as intermediate products of 2,7-DCDD degradation.
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Affiliation(s)
- Yuzoh Suzuki
- Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture & Technology, Koganei, Tokyo 184-8588, Japan
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Tiwari JN, Reddy MMK, Patel DK, Jain SK, Murthy RC, Manickam N. Isolation of pyrene degrading Achromobacter xylooxidans and characterization of metabolic product. World J Microbiol Biotechnol 2010. [DOI: 10.1007/s11274-010-0350-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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17
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Degradation of pyrene by an enteric bacterium, Leclercia adecarboxylata PS4040. Biodegradation 2009; 21:59-69. [DOI: 10.1007/s10532-009-9281-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2008] [Accepted: 06/18/2009] [Indexed: 10/20/2022]
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18
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Kimura N, Kamagata Y. Impact of dibenzofuran/dibenzo-p-dioxin amendment on bacterial community from forest soil and ring-hydroxylating dioxygenase gene populations. Appl Microbiol Biotechnol 2009; 84:365-73. [PMID: 19513710 DOI: 10.1007/s00253-009-2046-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2009] [Revised: 05/11/2009] [Accepted: 05/12/2009] [Indexed: 10/20/2022]
Abstract
The impact of dibenzofuran (DF) and dibenzo-p-dioxin (DD) on the changes in bacterial community structure and the transition of catabolic genes were studied using forest soil. The bacterial community structure of soil suspensions amended with 1 microg/g of either DF or DD was analyzed by 16S rRNA and functional gene sequencing. To analyze the functional genes in the communities, we targeted a gene sequence that functions as the binding site of Rieske iron sulfur center common to ring-hydroxylating dioxygenases (RHDs) for monocyclic, bicyclic, and tricyclic aromatic compounds. The gene fragments were polymerase chain reaction-amplified from DNAs extracted from soil suspensions spiked with either DF or DD, cloned, and sequenced (70 clones). Bacterial community analysis based on 16S rRNA genes revealed that specific 16S rRNA gene sequences, in particular, phylotypes within alpha-Proteobacteria, increased in the soil suspension amended with DF or DD. RHD gene-based functional community analysis showed that, in addition to two groups of RHD genes that were also detected in unamended soil suspensions, another two groups of RHD genes, each of which is specific to DF- and DD-amended soil, respectively, emerged to a great extent. The DD-specific genotype is phylogenetically distant from any known RHDs. These results strongly suggest that soil microbial community potentially harbors a wide array of organisms having diverse RHDs including those previously unknown, and that they could quickly respond to an impact of contamination of hazardous chemicals by changing the microbial community and gene diversity.
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Affiliation(s)
- Nobutada Kimura
- Institute for Biological Resources and Functions, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, 305-8566, Japan.
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The GAF-like-domain-containing transcriptional regulator DfdR is a sensor protein for dibenzofuran and several hydrophobic aromatic compounds. J Bacteriol 2008; 191:123-34. [PMID: 18952799 DOI: 10.1128/jb.01112-08] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Dibenzofuran (DF) is one of the dioxin carbon skeletal compounds used as a model to study the microbial degradation of dioxins. This study analyzed the transcriptional regulation of the DF dioxygenase genes dfdA1 to dfdA4 in the DF-utilizing actinomycetes Rhodococcus sp. strain YK2 and Terrabacter sp. strain YK3. An open reading frame designated dfdR was detected downstream of the dfdC genes. The C-terminal part of the DfdR amino acid sequence has high levels of similarity to several LuxR-type DNA binding helix-turn-helix domains, and a GAF domain sequence in the central part was detected by a domain search analysis. A derivative of YK2 with dfdR disrupted was not able to utilize DF and did not exhibit DF-dependent dfdA1 transcriptional induction ability, and these dysfunctions were compensated for by introduction of dfdR. Promoter analysis of dfdA1 in Rhodococcus strains indicated that activation of the dfdA1 promoter (P(dfdA1)) was dependent on dfdR and DF and not on a metabolite of the DF pathway. The cell extract of a Rhodococcus strain that heterologously expressed DfdR showed electrophoretic mobility shift (EMS) activity for the P(dfdA1) DNA fragment in a DF-dependent manner. In addition, P(dfdA1) activation and EMS activity were observed with hydrophobic aromatic compounds comprising two or more aromatic rings, suggesting that DfdR has broad effector molecule specificity for several hydrophobic aromatic compounds.
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Peng RH, Xiong AS, Xue Y, Fu XY, Gao F, Zhao W, Tian YS, Yao QH. Microbial biodegradation of polyaromatic hydrocarbons. FEMS Microbiol Rev 2008; 32:927-55. [PMID: 18662317 DOI: 10.1111/j.1574-6976.2008.00127.x] [Citation(s) in RCA: 392] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Polycyclic aromatic hydrocarbons (PAHs) are widespread in various ecosystems and are pollutants of great concern due to their potential toxicity, mutagenicity and carcinogenicity. Because of their hydrophobic nature, most PAHs bind to particulates in soil and sediments, rendering them less available for biological uptake. Microbial degradation represents the major mechanism responsible for the ecological recovery of PAH-contaminated sites. The goal of this review is to provide an outline of the current knowledge of microbial PAH catabolism. In the past decade, the genetic regulation of the pathway involved in naphthalene degradation by different gram-negative and gram-positive bacteria was studied in great detail. Based on both genomic and proteomic data, a deeper understanding of some high-molecular-weight PAH degradation pathways in bacteria was provided. The ability of nonligninolytic and ligninolytic fungi to transform or metabolize PAH pollutants has received considerable attention, and the biochemical principles underlying the degradation of PAHs were examined. In addition, this review summarizes the information known about the biochemical processes that determine the fate of the individual components of PAH mixtures in polluted ecosystems. A deeper understanding of the microorganism-mediated mechanisms of catalysis of PAHs will facilitate the development of new methods to enhance the bioremediation of PAH-contaminated sites.
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Affiliation(s)
- Ri-He Peng
- Shanghai Key Laboratory of Agricultural Genetics and Breeding, Agro-Biotechnology Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, China
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Tomás-Gallardo L, Canosa I, Santero E, Camafeita E, Calvo E, López JA, Floriano B. Proteomic and transcriptional characterization of aromatic degradation pathways in Rhodoccocus sp. strain TFB. Proteomics 2008; 6 Suppl 1:S119-32. [PMID: 16544280 DOI: 10.1002/pmic.200500422] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Rhodococcus sp. strain TFB is a versatile gram-positive bacterium able to grow on a wide variety of aromatic compounds as carbon and energy sources. Since the strain is refractory to genetic analysis, a proteomic approach was used to study the metabolic pathways involved in the catabolism of such compounds by analyzing differentially induced proteins. The most marked difference was observed when the proteome profiles of phthalate-grown cells were compared with those cultured in the presence of tetralin- or naphthalene, suggesting that different metabolic pathways are involved in the degradation of mono- and polyaromatic compounds. Comparison with the proteome of glucose-grown cells indicated that each pathway was specifically induced by the corresponding aromatic compound. A combination of proteomics and molecular biology led to the identification of 14 proteins (65-80% identical to known Pht proteins) that describe a complete pathway for the catabolism of phthalate to central metabolites via intradiol cleavage of protochatechuic acid. Chaperonins were also induced in phthalate-grown cells, indicating that growth on this compound induces a stress response. Absence of catabolite repression by glucose was observed by both transcriptional and proteome analysis, suggesting that Rhodococcus sp. strain TFB may have advantages over other tightly regulated strains in bioremediation.
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Affiliation(s)
- Laura Tomás-Gallardo
- Centro Andaluz de Biología del Desarrollo, Departamento de Ciencias Ambientales, Universidad Pablo de Olavide, Seville, Spain
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Miyauchi K, Sukda P, Nishida T, Ito E, Matsumoto Y, Masai E, Fukuda M. Isolation of dibenzofuran-degrading bacterium, Nocardioides sp. DF412, and characterization of its dibenzofuran degradation genes. J Biosci Bioeng 2008; 105:628-35. [DOI: 10.1263/jbb.105.628] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2008] [Accepted: 03/05/2008] [Indexed: 11/17/2022]
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Two angular dioxygenases contribute to the metabolic versatility of dibenzofuran-degrading Rhodococcus sp. strain HA01. Appl Environ Microbiol 2008; 74:3812-22. [PMID: 18441103 DOI: 10.1128/aem.00226-08] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Rhodococcus sp. strain HA01, isolated through its ability to utilize dibenzofuran (DBF) as the sole carbon and energy source, was also capable, albeit with low activity, of transforming dibenzo-p-dioxin (DD). This strain could also transform 3-chlorodibenzofuran (3CDBF), mainly by angular oxygenation at the ether bond-carrying carbon (the angular position) and an adjacent carbon atom, to 4-chlorosalicylate as the end product. Similarly, 2-chlorodibenzofuran (2CDBF) was transformed to 5-chlorosalicylate. However, lateral oxygenation at the 3,4-positions was also observed and yielded the novel product 2-chloro-3,4-dihydro-3,4-dihydroxydibenzofuran. Two gene clusters encoding enzymes for angular oxygenation (dfdA1A2A3A4 and dbfA1A2) were isolated, and expression of both was observed during growth on DBF. Heterologous expression revealed that both oxygenase systems catalyze angular oxygenation of DBF and DD but exhibited complementary substrate specificity with respect to CDBF transformation. While DfdA1A2A3A4 oxygenase, with high similarity to DfdA1A2A3A4 oxygenase from Terrabacter sp. strain YK3, transforms 3CDBF by angular dioxygenation at a rate of 29% +/- 4% that of DBF, 2CDBF was not transformed. In contrast, DbfA1A2 oxygenase, with high similarity to the DbfA1A2 oxygenase from Terrabacter sp. strain DBF63, exhibited complementary activity with angular oxygenase activity against 2CDBF but negligible activity against 3CDBF. Thus, Rhodococcus sp. strain HA01 constitutes the first described example of a bacterial strain where coexpression of two angular dioxygenases was observed. Such complementary activity allows for the efficient transformation of chlorinated DBFs.
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Zhou HW, Luan TG, Zou F, Tam NFY. Different bacterial groups for biodegradation of three- and four-ring PAHs isolated from a Hong Kong mangrove sediment. JOURNAL OF HAZARDOUS MATERIALS 2008; 152:1179-85. [PMID: 17868985 DOI: 10.1016/j.jhazmat.2007.07.116] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2006] [Revised: 07/30/2007] [Accepted: 07/31/2007] [Indexed: 05/17/2023]
Abstract
Mangrove sediments have been found to degrade three- to four-ring PAHs extensively. In the present study, 11 strains from 4 genera Mycobacterium (3 strains), Sphingomonas (5), Terrabacter (2) and Rhodococcus (1) were isolated from a single surface sediment sample of a Hong Kong mangrove swamp, among which the Terrabacter strains were isolated to grow with fluoranthene for the first time. Although all four genera could degrade three- and four-ring PAHs, their in situ activities in natural sediment slurry were found to be different. A cultivable method showed that Sphingomonas strains grew rapidly under the induction of three-ring, but not four-ring PAHs, while only Mycobacterium degrading strains dominated in the four-ring PAHs spiked slurry. Culture-independent method using a reverse transcriptional PCR showed expressions of nahAc-like (mainly found in Gram-negative bacteria) and nidA-like (in Gram-positive bacteria) dioxygenase genes parallel with the degradation of three- and four-ring PAHs, respectively. The present study suggested that surface mangrove sediments harbored diverse PAH-degrading bacteria, which showed different importance for biodegradation of three- and four-ring PAHs in the sediment.
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Affiliation(s)
- Hong Wei Zhou
- Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR, China
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25
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Characterization of a novel angular dioxygenase from fluorene-degrading Sphingomonas sp. strain LB126. Appl Environ Microbiol 2007; 74:1050-7. [PMID: 18156320 DOI: 10.1128/aem.01627-07] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In this study, the genes involved in the initial attack on fluorene by Sphingomonas sp. strain LB126 were investigated. The alpha and beta subunits of a dioxygenase complex (FlnA1-FlnA2), showing 63 and 51% sequence identity, respectively, to the subunits of an angular dioxygenase from the gram-positive dibenzofuran degrader Terrabacter sp. strain DBF63, were identified. When overexpressed in Escherichia coli, FlnA1-FlnA2 was responsible for the angular oxidation of fluorene, 9-hydroxyfluorene, 9-fluorenone, dibenzofuran, and dibenzo-p-dioxin. Moreover, FlnA1-FlnA2 was able to oxidize polycyclic aromatic hydrocarbons and heteroaromatics, some of which were not oxidized by the dioxygenase from Terrabacter sp. strain DBF63. The quantification of resulting oxidation products showed that fluorene and phenanthrene were the preferred substrates of FlnA1-FlnA2.
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26
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Yang X, Liu X, Song L, Xie F, Zhang G, Qian S. Characterization and functional analysis of a novel gene cluster involved in biphenyl degradation in Rhodococcus sp. strain R04. J Appl Microbiol 2007; 103:2214-24. [DOI: 10.1111/j.1365-2672.2007.03461.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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27
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Pagnout C, Frache G, Poupin P, Maunit B, Muller JF, Férard JF. Isolation and characterization of a gene cluster involved in PAH degradation in Mycobacterium sp. strain SNP11: Expression in Mycobacterium smegmatis mc2155. Res Microbiol 2007; 158:175-86. [PMID: 17258432 DOI: 10.1016/j.resmic.2006.11.002] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2006] [Revised: 11/22/2006] [Accepted: 11/24/2006] [Indexed: 10/23/2022]
Abstract
Mycobacterium sp. strain SNP11 is able to grow with pyrene, fluoranthene, phenanthrene and fluorene the sole carbon and energy sources. A probe based on the previously described gene pdoA2, which encodes the alpha subunit of a PAH ring-hydroxylating dioxygenase in Mycobacterium sp. strain 6PY1 [S. Krivobok et al., Identification of pyrene-induced proteins in Mycobacterium sp. strain 6PY1: evidence for two ring-hydroxylating dioxygenases, J. Bacteriol. 185(13) (2003) 3828-3841], was used to isolate a 14kb DNA fragment from strain SNP11. Twelve putative open reading frames (ORFs), divided into two groups by a promoter intergenic region, were detected in this DNA sequence. The first gene cluster, located upstream of the promoter region, showed low but significant deduced amino acid sequence homologies with enzymes involved in aromatic degradation. The second gene cluster, under control of the promoter, contained pdoA2 (designated phdA in this study) and several other ORFs with deduced amino acid sequences closely related to enzymes involved in the phenanthrene-degrading pathway of Nocardioides sp. strain KP7. Gene expression analysis in Mycobacterium smegmatis mc(2)155 revealed broad substrate specificity of the ring-hydroxylating dioxygenase, since transformant cells containing phdAB strongly oxidized fluoranthene, phenanthrene, anthracene, fluorine and dibenzofuran. Laser desorption/ionization time-of-flight mass spectrometry (LDI-ToF MS) analyses of culture media after PAH degradation by M. smegmatis transformants also revealed that the second gene cluster, located downstream of the promoter, takes an active share in initial phenanthrene and anthracene degradation by allowing transformation of these two PAHs in aromatic ring-cleaved metabolites.
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Affiliation(s)
- Christophe Pagnout
- Laboratoire d'Ecotoxicité, Santé Environnementale, CNRS UMR 7146, Université Paul Verlaine, rue du Général Delestraint, F-57070 Metz, France
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Shintani M, Urata M, Inoue K, Eto K, Habe H, Omori T, Yamane H, Nojiri H. The Sphingomonas plasmid pCAR3 is involved in complete mineralization of carbazole. J Bacteriol 2006; 189:2007-20. [PMID: 17172338 PMCID: PMC1855757 DOI: 10.1128/jb.01486-06] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We determined the complete 254,797-bp nucleotide sequence of the plasmid pCAR3, a carbazole-degradative plasmid from Sphingomonas sp. strain KA1. A region of about 65 kb involved in replication and conjugative transfer showed similarity to a region of plasmid pNL1 isolated from the aromatic-degrading Novosphingobium aromaticivorans strain F199. The presence of many insertion sequences, transposons, repeat sequences, and their remnants suggest plasticity of this plasmid in genetic structure. Although pCAR3 is thought to carry clustered genes for conjugative transfer, a filter-mating assay between KA1 and a pCAR3-cured strain (KA1W) was unsuccessful, indicating that pCAR3 might be deficient in conjugative transfer. Several degradative genes were found on pCAR3, including two kinds of carbazole-degradative gene clusters (car-I and car-II), and genes for electron transfer components of initial oxygenase for carbazole (fdxI, fdrI, and fdrII). Putative genes were identified for the degradation of anthranilate (and), catechol (cat), 2-hydroxypenta-2,4-dienoate (carDFE), dibenzofuran/fluorene (dbf/fln), protocatechuate (lig), and phthalate (oph). It appears that pCAR3 may carry clustered genes (car-I, car-II, fdxI, fdrI, fdrII, and, and cat) for the degradation of carbazole into tricarboxylic acid cycle intermediates; KA1W completely lost the ability to grow on carbazole, and the carbazole-degradative genes listed above were all expressed when KA1 was grown on carbazole. Reverse transcription-PCR analysis also revealed that the transcription of car-I, car-II, and cat genes was induced by carbazole or its metabolic intermediate. Southern hybridization analyses with probes prepared from car-I, car-II, repA, parA, traI, and traD genes indicated that several Sphingomonas carbazole degraders have DNA regions similar to parts of pCAR3.
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Affiliation(s)
- Masaki Shintani
- Biotechnology Research Center, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
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Zhou HW, Guo CL, Wong YS, Tam NFY. Genetic diversity of dioxygenase genes in polycyclic aromatic hydrocarbon-degrading bacteria isolated from mangrove sediments. FEMS Microbiol Lett 2006; 262:148-57. [PMID: 16923069 DOI: 10.1111/j.1574-6968.2006.00379.x] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
To investigate the diversity of dioxygenase genes involved in polycyclic aromatic hydrocarbon (PAH)-degradation, a total of 32 bacterial strains were isolated from surface mangrove sediments, from the genera Mycobacterium, Sphingomonas, Terrabacter, Sphingopyxis, Sphingobium and Rhodococcus. Two sets of PCR primers were constructed to detect the nidA-like and nahAc-like sequences of the alpha subunit of the PAH ring-hydroxylating dioxygenase. PCR amplified the DNA fragments from all Gram-positive bacteria by using nidA-like primers and from all Gram-negative bacteria, except two, by using nahAc-like primers. The nidA-like primers showed three subtypes of nidA-like gene: (i) fadA1, clustering with nidA3 from M. vanbaalenii PYR-1, (ii) nidA, clustering with nidA from PYR-1, and (iii) fadA2 clustering with dioxygenase from Arthrobacter sp. FB24. The amplicons detected by nahAc-like primers had high sequence homologies to phnA1a from Sphingomonas sp. CHY-1 and were amplifiable from 8 of the 16 Gram-negative isolates. The primer also generated amplicons that had a 32-36% similarity to phnA1a and 53-93% identity to p-cumate dioxygenase. These results suggest that the nidA-like and nahAc-like genes are prevalent in the PAH-degrading bacteria and that they are useful for determining the presence of PAH-dioxygenase genes in environmental samples.
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Affiliation(s)
- Hong Wei Zhou
- Department of Biology and Chemistry, City University of Hong Kong, Hong Kong SAR, China
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Ní Chadhain SM, Norman RS, Pesce KV, Kukor JJ, Zylstra GJ. Microbial dioxygenase gene population shifts during polycyclic aromatic hydrocarbon biodegradation. Appl Environ Microbiol 2006; 72:4078-87. [PMID: 16751518 PMCID: PMC1489606 DOI: 10.1128/aem.02969-05] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The degradation of polycyclic aromatic hydrocarbons (PAHs) by bacteria has been widely studied. While many pure cultures have been isolated and characterized for their ability to grow on PAHs, limited information is available on the diversity of microbes involved in PAH degradation in the environment. We have designed generic PCR primers targeting the gene fragment encoding the Rieske iron sulfur center common to all PAH dioxygenase enzymes. These Rieske primers were employed to track dioxygenase gene population shifts in soil enrichment cultures following exposure to naphthalene, phenanthrene, or pyrene. PAH degradation was monitored by gas chromatograph with flame ionization detection. DNA was extracted from the enrichment cultures following PAH degradation. 16S rRNA and Rieske gene fragments were PCR amplified from DNA extracted from each enrichment culture and an unamended treatment. The PCR products were cloned and sequenced. Molecular monitoring of the enrichment cultures before and after PAH degradation using denaturing gradient gel electrophoresis and 16S rRNA gene libraries suggests that specific phylotypes of bacteria were associated with the degradation of each PAH. Sequencing of the cloned Rieske gene fragments showed that different suites of genes were present in soil microbe populations under each enrichment culture condition. Many of the Rieske gene fragment sequences fell into clades which are distinct from the reference dioxygenase gene sequences used to design the PCR primers. The ability to profile not only the bacterial community but also the dioxygenases which they encode provides a powerful tool for both assessing bioremediation potential in the environment and for the discovery of novel dioxygenase genes.
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Affiliation(s)
- Sinéad M Ní Chadhain
- Biotechnology Center for Agriculture and the Environment, Rutgers University, 59 Dudley Rd., New Brunswick, NJ 08901-8520, USA
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Urata M, Uchimura H, Noguchi H, Sakaguchi T, Takemura T, Eto K, Habe H, Omori T, Yamane H, Nojiri H. Plasmid pCAR3 contains multiple gene sets involved in the conversion of carbazole to anthranilate. Appl Environ Microbiol 2006; 72:3198-205. [PMID: 16672458 PMCID: PMC1472349 DOI: 10.1128/aem.72.5.3198-3205.2006] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The carbazole degradative car-I gene cluster (carAaIBaIBbICIAcI) of Sphingomonas sp. strain KA1 is located on the 254-kb circular plasmid pCAR3. Carbazole conversion to anthranilate is catalyzed by carbazole 1,9a-dioxygenase (CARDO; CarAaIAcI), meta-cleavage enzyme (CarBaIBbI), and hydrolase (CarCI). CARDO is a three-component dioxygenase, and CarAaI and CarAcI are its terminal oxygenase and ferredoxin components. The car-I gene cluster lacks the gene encoding the ferredoxin reductase component of CARDO. In the present study, based on the draft sequence of pCAR3, we found multiple carbazole degradation genes dispersed in four loci on pCAR3, including a second copy of the car gene cluster (carAaIIBaIIBbIICIIAcII) and the ferredoxin/reductase genes fdxI-fdrI and fdrII. Biotransformation experiments showed that FdrI (or FdrII) could drive the electron transfer chain from NAD(P)H to CarAaI (or CarAaII) with the aid of ferredoxin (CarAcI, CarAcII, or FdxI). Because this electron transfer chain showed phylogenetic relatedness to that consisting of putidaredoxin and putidaredoxin reductase of the P450cam monooxygenase system of Pseudomonas putida, CARDO systems of KA1 can be classified in the class IIA Rieske non-heme iron oxygenase system. Reverse transcription-PCR (RT-PCR) and quantitative RT-PCR analyses revealed that two car gene clusters constituted operons, and their expression was induced when KA1 was exposed to carbazole, although the fdxI-fdrI and fdrII genes were expressed constitutively. Both terminal oxygenases of KA1 showed roughly the same substrate specificity as that from the well-characterized carbazole degrader Pseudomonas resinovorans CA10, although slight differences were observed.
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Affiliation(s)
- Masaaki Urata
- Biotechnology Research Center, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
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Xu P, Yu B, Li FL, Cai XF, Ma CQ. Microbial degradation of sulfur, nitrogen and oxygen heterocycles. Trends Microbiol 2006; 14:398-405. [PMID: 16860985 DOI: 10.1016/j.tim.2006.07.002] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2006] [Revised: 06/12/2006] [Accepted: 07/07/2006] [Indexed: 10/24/2022]
Abstract
Sulfur (S), nitrogen (N) and oxygen (O) heterocycles are among the most potent environmental pollutants. Microbial degradation of these pollutants is attracting more and more attention because such bioprocesses are environmentally friendly. The biotechnological potential of these processes is being investigated, for example, to achieve better sulfur removal by immobilized biocatalysts with magnetite nanoparticles or by solvent-tolerant bacteria, and to obtain valuable intermediates from these heterocycles. Other recent advances have demonstrated the mechanisms of angular dioxygenation of nitrogen heterocycles by microbes. However, these technologies are not yet available for large-scale applications so future research must investigate proper modifications for industrial applications of these processes. This review focuses on recent progress in understanding how microbes degrade S, N and O heterocycles.
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Affiliation(s)
- Ping Xu
- State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, People's Republic of China.
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Jin S, Zhu T, Xu X, Xu Y. Biodegradation of Dibenzofuran by Janibacter terrae Strain XJ-1. Curr Microbiol 2006; 53:30-6. [PMID: 16775784 DOI: 10.1007/s00284-005-0180-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2005] [Accepted: 12/02/2005] [Indexed: 10/24/2022]
Abstract
The dibenzofuran (DF)-degrading bacterium, Janibacter terrae strain XJ-1, was isolated from sediment from East Lake in Wuhan, China. This strain grows aerobically on DF as the sole source of carbon and energy; it has a doubling time of 12 hours at 30 degrees C; and it almost completely degraded 100 mg/L(-1) DF in 5 days, producing 2,2',3-trihydroxybiphenyl, salicylic acid, gentisic acid, and other metabolites. The dbdA (DF dioxygenase) gene cluster in the strain is almost identical to that on a large plasmid in Terrabacter sp. YK3. Unlike Janibacter sp. strain YY-1, XJ-1 accumulates gentisic acid rather than catechol as a final product of DF degradation.
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Affiliation(s)
- Shiwei Jin
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, China
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Kimura N, Kitagawa W, Mori T, Nakashima N, Tamura T, Kamagata Y. Genetic and biochemical characterization of the dioxygenase involved in lateral dioxygenation of dibenzofuran from Rhodococcus opacus strain SAO101. Appl Microbiol Biotechnol 2006; 73:474-84. [PMID: 16736088 DOI: 10.1007/s00253-006-0481-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2006] [Revised: 04/19/2006] [Accepted: 04/20/2006] [Indexed: 10/24/2022]
Abstract
Rhodococcus opacus strain SAO101 was shown to degrade on various polycyclic aromatic hydrocarbons such as naphthalene, dibenzofuran (DF), and dibenzo-p-dioxin (DD). One of the unique traits of the strain SAO101 is its ability to oxidize DF compounds by lateral dioxygenation. To clone the lateral dioxygenase gene involved in compound degradation in strain SAO101, we identified a cosmid clone that oxidizes aromatic compounds by using SAO101 genomic DNA. Sequencing analysis revealed that isolated cosmid clone contained ring-hydroxylating dioxygenase genes (narAaAb) with homologies to indene dioxygenase genes of Rhodococcus strain I24 and naphthalene dioxygenase genes of Rhodococcus strain NCIMB12038. The NarAaAb-expressing Rhodococcus cells exhibited broad substrate specificity for bicyclic aromatic compounds and had high ability to degrade dibenzofuran and naphthalene. Metabolite analysis revealed that dihydrodiol compounds were detected as metabolites from dibenzofuran by the NarAaAb-expressing Rhodococcus strain, indicating that dibenzofuran was converted by lateral dioxygenase activity of NarA dioxygenase. Based on reverse transcriptase-polymerase chain reaction analysis, it was found that the narAaAb genes were cotranscribed and that their expression was induced in the presence of aromatic hydrocarbon compounds. It is likely that these genes are involved in the degradation pathways of a wide range of aromatic hydrocarbons by this strain. Strain SAO101 harbors three huge linear plasmids, pWK301 (1,100 kbp), pWK302 (1,000 kbp), and pWK303 (700 kbp), and the nar genes were found to be located on the pWK301 plasmid.
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Affiliation(s)
- Nobutada Kimura
- Institute for Biological Resources and Functions, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8566, Japan.
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Habe H, Chung JS, Ishida A, Kasuga K, Ide K, Takemura T, Nojiri H, Yamane H, Omori T. The fluorene catabolic linear plasmid in Terrabacter sp. strain DBF63 carries the beta-ketoadipate pathway genes, pcaRHGBDCFIJ, also found in proteobacteria. MICROBIOLOGY-SGM 2005; 151:3713-3722. [PMID: 16272392 DOI: 10.1099/mic.0.28215-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Terrabacter sp. strain DBF63 is capable of degrading fluorene (FN) to tricarboxylic acid cycle intermediates via phthalate and protocatechuate. Genes were identified for the protocatechuate branch of the beta-ketoadipate pathway (pcaR, pcaHGBDCFIJ) by sequence analysis of a 70 kb DNA region of the FN-catabolic linear plasmid pDBF1. RT-PCR analysis of RNA from DBF63 cells grown with FN, dibenzofuran, and protocatechuate indicated that the pcaHGBDCFIJ operon was expressed during both FN and protocatechuate degradation in strain DBF63. The gene encoding beta-ketoadipate enol-lactone hydrolase (pcaD) was not fused to the next gene, which encodes gamma-carboxymuconolactone decarboxylase (pcaC), in strain DBF63, even though the presence of the pcaL gene (the fusion of pcaD and pcaC) within a pca gene cluster has been thought to be a Gram-positive trait. Quantitative RT-PCR analysis revealed that pcaD mRNA levels increased sharply in response to protocatechuate, and a biotransformation experiment with cis,cis-muconate using Escherichia coli carrying both catBC and pcaD indicated that PcaD exhibited beta-ketoadipate enol-lactone hydrolase activity. The location of the pca gene cluster on the linear plasmid, and the insertion sequences around the pca gene cluster suggest that the ecologically important beta-ketoadipate pathway genes, usually located chromosomally, may be spread widely among bacterial species via horizontal transfer or transposition events.
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Affiliation(s)
- Hiroshi Habe
- Biotechnology Research Center, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Jin-Sung Chung
- Biotechnology Research Center, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Ayako Ishida
- Department of Chemistry, Faculty of Sciences, Science University of Tokyo, 1-3 Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan
| | - Kano Kasuga
- Department of Biotechnology, Faculty of Bioresource Sciences, Akita Prefectural University, 241-7 Kaidobata-nishi, Shimoshinjo-nakano, Akita 010-0195, Japan
| | - Kazuki Ide
- Geo and Water Environmental Engineering Department, Obayashi Corporation, 4-640 Shimokiyoto, Kiyose-shi, Tokyo 204-0011, Japan
| | - Tetsuo Takemura
- Department of Chemistry, Faculty of Sciences, Science University of Tokyo, 1-3 Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan
| | - Hideaki Nojiri
- Biotechnology Research Center, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Hisakazu Yamane
- Biotechnology Research Center, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Toshio Omori
- Biotechnology Research Center, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
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Iida T, Nakamura K, Izumi A, Mukouzaka Y, Kudo T. Isolation and characterization of a gene cluster for dibenzofuran degradation in a new dibenzofuran-utilizing bacterium, Paenibacillus sp. strain YK5. Arch Microbiol 2005; 184:305-15. [PMID: 16284749 DOI: 10.1007/s00203-005-0045-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2005] [Revised: 08/15/2005] [Accepted: 09/19/2005] [Indexed: 10/25/2022]
Abstract
Spore-forming bacterial strains capable of utilizing dibenzofuran (DF) as a sole source of carbon and energy were isolated. Characteristics of the isolates justified their classification into the genus Paenibacillus, and their closest relative was P. naphthalenovorans. Degenerate primers for aromatic hydrocarbon dioxygenase alpha subunit (AhDOa) genes and genomic DNA of the strain YK5 were used for gene isolation. The nucleotide sequences of clones of the PCR products revealed that the strain YK5 carries at least five different AhDOa genes. Northern hybridization analysis showed that one of the AhDOa genes was transcribed under DF-containing culture conditions. A gene cluster encoding the AhDOa was isolated. The genes predicted to encode extradiol dioxygenase (dbfB) and hydrolase (dbfC) were found to be an upstream of genes encoding the alpha and beta subunit of the AhDO (dbfA1 and dbfA2, respectively); the latter two gene products showed 60 and 53% identity to the amino acid sequences of DbfA1 and DbfA2 of Terrabacter sp. DBF63, respectively. Two Paenibacillus validus JCM 9077 strains transformed with the dbf gene clusters acquired the ability to convert DF to 2,2',3-trihydroxybiphenyl (THBP) and salicylic acid (SAL). These results suggest that the enzymes encoded by the gene cluster isolated in this study are involved in DF metabolism in YK5.
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Affiliation(s)
- Toshiya Iida
- Environmental Molecular Biology Laboratory, RIKEN, Wako, Saitama 351-0198, Japan.
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Takagi T, Habe H, Yoshida T, Yamane H, Omori T, Nojiri H. Characterization of [3Fe-4S] ferredoxin DbfA3, which functions in the angular dioxygenase system of Terrabacter sp. strain DBF63. Appl Microbiol Biotechnol 2005; 68:336-45. [PMID: 15717172 DOI: 10.1007/s00253-005-1928-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2004] [Revised: 12/26/2004] [Accepted: 01/21/2005] [Indexed: 10/25/2022]
Abstract
Dibenzofuran 4,4a-dioxygenase (DFDO) from Terrabacter sp. strain DBF63 is comprised of three components, i.e., terminal oxygenase (DbfA1, DbfA2), putative [3Fe-4S] ferredoxin (ORF16b product), and unidentified ferredoxin reductase. We produced DbfA1 and DbfA2 using recombinant Escherichia coli BL21(DE3) cells as a native form and purified the complex to apparent homogeneity. We also produced and purified a putative [3Fe-4S] ferredoxin encoded by ORF16b, which is located 2.5 kb downstream of the dbfA1A2 genes, with E. coli as a histidine (His)-tagged form. The reconstructed DFDO system with three purified components, i.e., DbfA1A2, His-tagged ORF16b product, and His-tagged PhtA4 (which is a tentative reductase derived from the phthalate dioxygenase system of strain DBF63) could convert fluorene to 9-fluorenol (specific activity: 14.4 nmol min(-1) mg(-1)) and convert dibenzofuran to 2,2',3-trihydroxybiphenyl. This indicates that the ORF16b product can transport electrons to the DbfA1A2 complex; and therefore it was designated DbfA3. Based on spectroscopic UV-visible absorption characteristics and electron paramagnetic resonance spectra, DbfA3 was elucidated to contain a [3Fe-4S] cluster. Ferredoxin interchangeability analysis using several types of ferredoxins suggested that the redox partner of the DbfA1A2 complex may be rather specific to DbfA3.
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Affiliation(s)
- Terufumi Takagi
- Biotechnology Research Center, The University of Tokyo, Bunkyo-ku, Japan
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L'Abbée JB, Barriault D, Sylvestre M. Metabolism of dibenzofuran and dibenzo-p-dioxin by the biphenyl dioxygenase of Burkholderia xenovorans LB400 and Comamonas testosteroni B-356. Appl Microbiol Biotechnol 2005; 67:506-14. [PMID: 15700128 DOI: 10.1007/s00253-004-1791-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2004] [Revised: 09/23/2004] [Accepted: 10/04/2004] [Indexed: 10/25/2022]
Abstract
We examined the metabolism of dibenzofuran (DF) and dibenzo-p-dioxin (DD) by the biphenyl dioxygenase (BPDO) of Comamonas testosteroni B-356 and compared it with that of Burkholderia xenovorans LB400. Data showed that both enzymes oxygenated DF at a low rate, but Escherichia coli cells expressing LB400 BPDO degraded DF at higher rate (30 nmol in 18 h) compared with cells expressing B-356 BPDO (2 nmol in 18 h). Furthermore, both BPDOs produced dihydro-dihydroxy-dibenzofuran as a major metabolite, which resulted from the lateral oxygenation of DF. 2,2',3-Trihydroxybiphenyl (resulting from angular oxygenation of DF) was a minor metabolite produced by both enzymes. Deuterated DF was used to demonstrate the production of 2,2',3-dihydroxybiphenyl through angular oxygenation of DF. When tested for their ability to oxygenate DD, both enzymes produced as sole metabolite, 2,2',3-trihydroxybiphenyl ether at about the same rate, indicating similar catalytic properties toward this substrate. Altogether, although LB400 and B-356 BPDOs oxygenate a different range of chlorobiphenyls, their metabolite profiles toward DF and DD are similar. This suggests that co-planarity influences the regiospecificity of BPDO toward DF and DD to a higher extent than the presence of an ortho substituent on the molecule.
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Affiliation(s)
- José-Bruno L'Abbée
- Institut National de la Recherche Scientifique, INRS-Institut Armand-Frappier, Québec, Canada
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Noumura T, Habe H, Widada J, Chung JS, Yoshida T, Nojiri H, Omori T. Genetic characterization of the dibenzofuran-degrading Actinobacteria carrying thedbfA1A2gene homologues isolated from activated sludge. FEMS Microbiol Lett 2004; 239:147-55. [PMID: 15451113 DOI: 10.1016/j.femsle.2004.08.032] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2004] [Revised: 08/15/2004] [Accepted: 08/24/2004] [Indexed: 11/30/2022] Open
Abstract
Thirteen dibenzofuran (DF)-utilizing bacteria carrying the DF terminal dioxygenase genes homologous to those of Terrabacter sp. strain DBF63 (dbfA1A2) were newly isolated from activated sludge samples. The amplified ribosomal DNA restriction analysis and the hybridization analyses showed that these strains were grouped into five genetically different types of bacteria. The sequence analyses of the 16S rRNA genes and the dbfA1A2 homologues from these five selected isolates revealed that the isolates belonged to the genus Rhodococcus, Terrabacter or Janibacter and that they shared 99-100% conserved dbfA1A2 homologues. We investigated the genetic organizations flanking the dbfA1A2 homologues and showed that the minimal conserved DNA region present in all five selected isolates consisted of an approximately 9.0-kb region and that their outer regions became abruptly non-homologous. Among them, Rhodococcus sp. strain DFA3 possessed not only the 9.0-kb region but also the 6.2-kb region containing dbfA1A2 homologues. Sequencing of their border regions suggested that some genetic rearrangement might have occurred with insertion sequence-like elements. Also, within their conserved regions, some insertions or deletions were observed.
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Affiliation(s)
- Takashi Noumura
- Biotechnology Research Center, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
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Habe H, Chung JS, Kato H, Ayabe Y, Kasuga K, Yoshida T, Nojiri H, Yamane H, Omori T. Characterization of the upper pathway genes for fluorene metabolism in Terrabacter sp. strain DBF63. J Bacteriol 2004; 186:5938-44. [PMID: 15317800 PMCID: PMC516849 DOI: 10.1128/jb.186.17.5938-5944.2004] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Genes involved in the degradation of fluorene to phthalate were characterized in the fluorene degrader Terrabacter sp. strain DBF63. The initial attack on both fluorene and 9-fluorenone was catalyzed by DbfA to yield 9-fluorenol and 1,1a-dihydroxy-1-hydro-9-fluorenone, respectively. The FlnB protein exhibited activities against both 9-fluorenol and 1,1a-dihydroxy-1-hydro-9-fluorenone to produce 9-fluorenone and 2'-carboxy-2,3-dihydroxybiphenyl, respectively. FlnD is a heteromeric protein encoded by flnD1 and ORF16, being a member of the class III two-subunit extradiol dioxygenase. FlnE was identified as a serine hydrolase for the meta-cleavage products that yield phthalate.
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Affiliation(s)
- Hiroshi Habe
- Biotechnology Research Center, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
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Zocca C, Gregorio S, Visentini F, Vallini G. Biodiversity amongst cultivable polycyclic aromatic hydrocarbon-transforming bacteria isolated from an abandoned industrial site. FEMS Microbiol Lett 2004. [DOI: 10.1111/j.1574-6968.2004.tb09779.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Pinyakong O, Habe H, Kouzuma A, Nojiri H, Yamane H, Omori T. Isolation and characterization of genes encoding polycyclic aromatic hydrocarbon dioxygenase from acenaphthene and acenaphthylene degradingSphingomonassp. strain A4. FEMS Microbiol Lett 2004. [DOI: 10.1111/j.1574-6968.2004.tb09770.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Ishiyama D, Vujaklija D, Davies J. Novel pathway of salicylate degradation by Streptomyces sp. strain WA46. Appl Environ Microbiol 2004; 70:1297-306. [PMID: 15006746 PMCID: PMC368302 DOI: 10.1128/aem.70.3.1297-1306.2004] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A novel salicylate-degrading Streptomyces sp., strain WA46, was identified by UV fluorescence on solid minimal medium containing salicylate; trace amounts of gentisate were detected by high-pressure liquid chromatography when strain WA46 was grown with salicylate. PCR amplification of WA46 DNA with degenerate primers for gentisate 1,2-dioxygenase (GDO) genes produced an amplicon of the expected size. Sequential PCR with nested GDO primers was then used to identify a salicylate degradation gene cluster in a plasmid library of WA46 chromosomal DNA. The nucleotide sequence of a 13.5-kb insert in recombinant plasmid pWD1 (which was sufficient for the complete degradation of salicylate) showed that nine putative open reading frames (ORFs) (sdgABCDEFGHR) were involved. Plasmid pWD1 derivatives disrupted in each putative gene were transformed into Streptomyces lividans TK64. Disruption of either sdgA or sdgC blocked salicylate degradation; constructs lacking sdgD accumulated gentisate. Cell extracts from Escherichia coli DH5 alpha transformants harboring pUC19 that expressed each of the sdg ORFs showed that conversions of salicylate to salicylyl-coenzyme A (CoA) and salicylyl-CoA to gentisyl-CoA required SdgA and SdgC, respectively. SdgA required CoA and ATP as cofactors, while NADH was required for SdgC activity; SdgC was identified as salicylyl-CoA 5-hydroxylase. Gentisyl-CoA underwent spontaneous cleavage to gentisate and CoA. SdgA behaved as a salicylyl-CoA ligase despite showing amino acid sequence similarity to an AMP-ligase. SdgD was identified as a GDO. These results suggest that Streptomyces sp. strain WA46 degrades salicylate by a novel pathway via a CoA derivative. Two-dimensional polyacrylamide gel electrophoresis and reverse transcriptase-PCR studies indicated that salicylate induced expression of the sdg cluster.
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Affiliation(s)
- Daisuke Ishiyama
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3
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Krivobok S, Kuony S, Meyer C, Louwagie M, Willison JC, Jouanneau Y. Identification of pyrene-induced proteins in Mycobacterium sp. strain 6PY1: evidence for two ring-hydroxylating dioxygenases. J Bacteriol 2003; 185:3828-41. [PMID: 12813077 PMCID: PMC161579 DOI: 10.1128/jb.185.13.3828-3841.2003] [Citation(s) in RCA: 159] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2003] [Accepted: 04/14/2003] [Indexed: 11/20/2022] Open
Abstract
In this study, the enzymes involved in polycyclic aromatic hydrocarbon (PAH) degradation were investigated in the pyrene-degrading Mycobacterium sp. strain 6PY1. [(14)C]pyrene mineralization experiments showed that bacteria grown with either pyrene or phenanthrene produced high levels of pyrene-catabolic activity but that acetate-grown cells had no activity. As a means of identifying specific catabolic enzymes, protein extracts from bacteria grown on pyrene or on other carbon sources were analyzed by two-dimensional gel electrophoresis. Pyrene-induced proteins were tentatively identified by peptide sequence analysis. Half of them resembled enzymes known to be involved in phenanthrene degradation, with closest similarity to the corresponding enzymes from Nocardioides sp. strain KP7. The genes encoding the terminal components of two distinct ring-hydroxylating dioxygenases were cloned. Sequence analysis revealed that the two enzymes, designated Pdo1 and Pdo2, belong to a subfamily of dioxygenases found exclusively in gram-positive bacteria. When overproduced in Escherichia coli, Pdo1 and Pdo2 showed distinctive selectivities towards PAH substrates, with the former enzyme catalyzing the dihydroxylation of both pyrene and phenanthrene and the latter preferentially oxidizing phenanthrene. The catalytic activity of the Pdo2 enzyme was dramatically enhanced when electron carrier proteins of the phenanthrene dioxygenase from strain KP7 were coexpressed in recombinant cells. The Pdo2 enzyme was purified as a brown protein consisting of two types of subunits with M(r)s of about 52,000 and 20,000. Immunoblot analysis of cell extracts from strain 6PY1 revealed that Pdo1 was present in cells grown on benzoate, phenanthrene, or pyrene and absent in acetate-grown cells. In contrast, Pdo2 could be detected only in PAH-grown cells. These results indicated that the two enzymes were differentially regulated depending on the carbon source used for growth.
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Affiliation(s)
- Serge Krivobok
- Laboratoire de Biochimie et Biophysique des Systèmes Intégrés, CNRS UMR 5092, CEA-Grenoble, F-38054 Grenoble Cedex 9, France
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Brezna B, Khan AA, Cerniglia CE. Molecular characterization of dioxygenases from polycyclic aromatic hydrocarbon-degrading Mycobacterium spp. FEMS Microbiol Lett 2003; 223:177-83. [PMID: 12829283 DOI: 10.1016/s0378-1097(03)00328-8] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Polycyclic aromatic hydrocarbon (PAH)-degrading genes nidA and nidB that encode the alpha and beta subunits of the aromatic ring-hydroxylating dioxygenase have been cloned and sequenced from Mycobacterium vanbaalenii PYR-1 [Khan et al., Appl. Environ Microbiol. 67 (2001) 3577-3585]. In this study, the presence of nidA and nidB in 12 other Mycobacterium or Rhodococcus strains was investigated. Initially, all strains were screened for their ability to degrade PAHs by a spray plate method, and for the presence of the dioxygenase Rieske center region by polymerase chain reaction (PCR). Only Mycobacterium sp. PAH 2.135 (RJGII-135), M. flavescens PYR-GCK (ATCC 700033), M. gilvum BB1 (DSM 9487) and M. frederiksbergense FAn9T (DSM 44346), all previously known PAH degraders, were positive in both tests. From the three positive strains, complete open reading frames of the nidA and nidB genes were amplified by PCR, using primers designed according to the known nidA and nidB sequences from PYR-1, cloned in the pBAD/Thio-TOPO vector and sequenced. The sequences showed >98% identity with the M. vanbaalenii PYR-1 nidA and nidB genes. Southern DNA-DNA hybridization using nidA and nidB probes from PYR-1 revealed that there is more than one copy of nidA and nidB genes in the strains PYR-1, BB1, PYR-GCK and FAn9T. However, only one copy of each gene was observed in PAH2.135.
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Affiliation(s)
- Barbara Brezna
- Division of Microbiology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079, USA
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Hiraishi A. Biodiversity of Dioxin-Degrading Microorganisms and Potential Utilization in Bioremediation. Microbes Environ 2003. [DOI: 10.1264/jsme2.18.105] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Akira Hiraishi
- Department of Ecological Engineering, Toyohashi University of Technology
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47
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Nam JW, Nojiri H, Noguchi H, Uchimura H, Yoshida T, Habe H, Yamane H, Omori T. Purification and characterization of carbazole 1,9a-dioxygenase, a three-component dioxygenase system of Pseudomonas resinovorans strain CA10. Appl Environ Microbiol 2002; 68:5882-90. [PMID: 12450807 PMCID: PMC134387 DOI: 10.1128/aem.68.12.5882-5890.2002] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The carbazole 1,9a-dioxygenase (CARDO) system of Pseudomonas resinovorans strain CA10 consists of terminal oxygenase (CarAa), ferredoxin (CarAc), and ferredoxin reductase (CarAd). Each component of CARDO was expressed in Escherichia coli strain BL21(DE3) as a native form (CarAa) or a His-tagged form (CarAc and CarAd) and was purified to apparent homogeneity. CarAa was found to be trimeric and to have one Rieske type [2Fe-2S] cluster and one mononuclear iron center in each monomer. Both His-tagged proteins were found to be monomeric and to contain the prosthetic groups predicted from the deduced amino acid sequence (His-tagged CarAd, one FAD and one [2Fe-2S] cluster per monomer protein; His-tagged CarAc, one Rieske type [2Fe-2S] cluster per monomer protein). Both NADH and NADPH were effective as electron donors for His-tagged CarAd. However, since the k(cat)/K(m) for NADH is 22.3-fold higher than that for NADPH in the 2,6-dichlorophenolindophenol reductase assay, NADH was supposed to be the physiological electron donor of CarAd. In the presence of NADH, His-tagged CarAc was reduced by His-tagged CarAd. Similarly, CarAa was reduced by His-tagged CarAc, His-tagged CarAd, and NADH. The three purified proteins could reconstitute the CARDO activity in vitro. In the reconstituted CARDO system, His-tagged CarAc seemed to be indispensable for electron transport, while His-tagged CarAd could be replaced by some unrelated reductases.
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Affiliation(s)
- Jeong-Won Nam
- Biotechnology Research Center, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Japan
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48
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Nojiri H, Kamakura M, Urata M, Tanaka T, Chung JS, Takemura T, Yoshida T, Habe H, Omori T. Dioxin catabolic genes are dispersed on the Terrabacter sp. DBF63 genome. Biochem Biophys Res Commun 2002; 296:233-40. [PMID: 12163007 DOI: 10.1016/s0006-291x(02)00873-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Reverse transcription-PCR of the dbfA1A2, dbfBC, and pht genes, encoding oxygenase component of multicomponent dioxygenase, meta cleavage enzyme and hydrolase, and phthalate-degrading enzymes, respectively, revealed their role in the aromatic compound degradation by Terrabacter sp. strain DBF63. The specific expression in strain DBF63 cells grown on dibenzofuran (the model compound of dioxin; DF) and/or fluorene (FN) indicated that the DbfA1A2 and DbfBC catalyze the conversion of DF to salicylate, and that the DbfA1A2 and Pht enzymes are involved in FN degradation. Pulsed-field gel electrophoresis analyses revealed that the dbfA1A2 cistron and pht operon were located on the two linear plasmids, pDBF1 (160 kb) and pDBF2 (190 kb), while dbfBC genes were located on the chromosome. Because the pht operon is located immediately upstream of the dbfA1A2 cistron, the dioxin-catabolic genes were dispersed on the genome of strain DBF63, while FN-catabolic genes were gathered on the plasmids.
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Affiliation(s)
- Hideaki Nojiri
- Biotechnology Research Center, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, Japan
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Iida T, Mukouzaka Y, Nakamura K, Kudo T. Plasmid-borne genes code for an angular dioxygenase involved in dibenzofuran degradation by Terrabacter sp. strain YK3. Appl Environ Microbiol 2002; 68:3716-23. [PMID: 12147464 PMCID: PMC124003 DOI: 10.1128/aem.68.8.3716-3723.2002] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The genes responsible for angular dioxygenation of dibenzofuran in actinomycetes were cloned by using a degenerate set of PCR primers designed by using conserved sequences of the dioxygenase alpha subunit genes. One sequence of alpha subunit genes was commonly amplified from four dibenzofuran-utilizing actinomycetes: Terrabacter sp. strains YK1 and YK3, Rhodococcus sp. strain YK2, and Microbacterium sp. strain YK18. A 5.2-kb PstI fragment encoding the alpha and beta subunits of the terminal dioxygenase, ferredoxin, and ferredoxin reductase (designated dfdA1 to dfdA4, respectively) was cloned from the large circular plasmid pYK3 isolated from Terrabacter sp. strain YK3. We confirmed that transcription of the dfdA1 gene was induced by dibenzofuran in Terrabacter sp. strain YK3. Southern blot hybridization analysis revealed that this type of dioxygenase gene is distributed among diverse dibenzofuran-utilizing actinomycetes. However, genes homologous to dfdA1 were not detected in dibenzofuran utilization-deficient mutants of Terrabacter, Rhodococcus, and Microbacterium species. When the dfdA1 to dfdA4 genes were introduced into a non-dibenzofuran-degrading mutant of Rhodococcus sp. strain YK2, strain YK2-RD2, which had spontaneously lost the gene homologous to dfdA1, the ability to degrade dibenzofuran was restored. Analysis of the breakdown products indicated that DfdA has angular dioxygenase activity. This dfdA transformant degraded several aromatic compounds, indicating that the novel angular dioxygenase possesses broad substrate specificity.
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Affiliation(s)
- Toshiya Iida
- Microbiology Laboratory, RIKEN (The Institute of Physical and Chemical Research) Bio-Recycle Project, Japan Science and Technology Corporation (JST), Wako, Saitama 351-0198, Japan.
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Habe H, Ide K, Yotsumoto M, Tsuji H, Yoshida T, Nojiri H, Omori T. Degradation characteristics of a dibenzofuran-degrader Terrabacter sp. strain DBF63 toward chlorinated dioxins in soil. CHEMOSPHERE 2002; 48:201-207. [PMID: 12117055 DOI: 10.1016/s0045-6535(02)00064-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
To obtain basic information towards applying a dibenzofuran (DF)-degrader Terrabacter sp. strain DBF63 to bioremediate dioxin-contaminated soil, we investigated the degradative potential of strain DBF63 for either chlorinated or polychlorinated dibenzo-p-dioxins and dibenzofurans (ClxDD/ClxDF) in soil. In the soil slurry system with a soil to water ratio of 1:5 (w/v), the DF-grown DBF63 cells degraded 90% of 1 ppm 2,8-Cl2DF, whereas only 40% of 1 ppm 2,3-Cl2DD during the 7-day incubation. The degradation rates of 2-CIDF, 2-ClDD, 2,8-Cl2DF and 2,3-Cl2DF by strain DBF63 in the soil slurry system (5-day incubation) were approximately 89%, 65%, 78% and 32%, respectively. These results suggest that strain DBF63 was able to degrade mono- to dichlorinated dibenzofurans more effectively than mono- to dichlorinated dibenzo-p-dioxins. Using the same soil slurry system, we performed a preliminary bioremediation experiment using the actual dioxin-contaminated soil at an incineration site. We found that approximately 10% of tetra- to hexa-chlorinated congeners was decreased by a single inoculation with DBF63 cells within a 7-day incubation.
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Affiliation(s)
- Hiroshi Habe
- Biotechnology Research Center, The University of Tokyo, Japan
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