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Kutraite I, Malys N. Development and Application of Whole-Cell Biosensors for the Detection of Gallic Acid. ACS Synth Biol 2023; 12:533-543. [PMID: 36724292 PMCID: PMC9942251 DOI: 10.1021/acssynbio.2c00537] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Gallic acid is a prevalent secondary plant metabolite distinguished as one of the most effective free-radical scavengers among phenolic acids. This compound is also known for its cytotoxic, anti-inflammatory, and antimicrobial activities. Bulk quantities of gallic acid are conventionally produced by acid hydrolysis of tannins, a costly and environmentally hazardous process. With the aim to develop more sustainable approaches, microbial bioproduction strategies have been attempted recently. To advance synthetic biology and metabolic engineering of microorganisms for gallic acid production, we characterize here a transcription factor-based inducible system PpGalR/PPP_RS13150 that responds to the extracellular gallic acid in a dose-dependent manner in Pseudomonas putida KT2440. Surprisingly, this compound does not mediate induction when PpGalR/PPP_RS13150 is used in non-native host background. We show that the activation of the inducible system requires gallate dioxygenase activity encoded by galA gene. The 4-oxalomesaconic acid, an intermediate of gallic acid-metabolism, is identified as the effector molecule that interacts with the transcription factor GalR mediating activation of gene expression. Introduction of galA gene along galR enables development of biosensors suitable for detection and monitoring of gallic acid extracellularly using non-native hosts such as E. coli and C. necator. Moreover, the P. putida-based biosensor's applicability is demonstrated by detecting and measuring gallic acid in extracts of Camellia sinensis leaves. This study reports the strategy, which can be applied for developing gallic acid biosensors using bacterial species outside Pseudomonas genus.
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Affiliation(s)
- Ingrida Kutraite
- Bioprocess
Research Centre, Faculty of Chemical Technology, Kaunas University of Technology, Radvilėnų Street 19, LT-50254Kaunas, Lithuania
| | - Naglis Malys
- Bioprocess
Research Centre, Faculty of Chemical Technology, Kaunas University of Technology, Radvilėnų Street 19, LT-50254Kaunas, Lithuania,Department
of Organic Chemistry, Faculty of Chemical Technology, Kaunas University of Technology, Radvilėnų Street 19, LT-50254Kaunas, Lithuania,
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2
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Identification of a Phylogenetically Divergent Vanillate O-Demethylase from Rhodococcus ruber R1 Supporting Growth on Meta-Methoxylated Aromatic Acids. Microorganisms 2022; 11:microorganisms11010078. [PMID: 36677370 PMCID: PMC9867520 DOI: 10.3390/microorganisms11010078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 12/22/2022] [Accepted: 12/23/2022] [Indexed: 12/29/2022] Open
Abstract
Rieske-type two-component vanillate O-demethylases (VanODs) catalyze conversion of the lignin-derived monomer vanillate into protocatechuate in several bacterial species. Currently, VanODs have received attention because of the demand of effective lignin valorization technologies, since these enzymes own the potential to catalyze methoxy group demethylation of distinct lignin monomers. In this work, we identified a phylogenetically divergent VanOD from Rhodococcus ruber R1, only distantly related to previously described homologues and whose presence, along with a 3-hydroxybenzoate/gentisate pathway, correlated with the ability to grow on other meta-methoxylated aromatics, such as 3-methoxybenzoate and 5-methoxysalicylate. The complementation of catabolic abilities by heterologous expression in a host strain unable to grow on vanillate, and subsequent resting cell assays, suggest that the vanAB genes of R1 strain encode a proficient VanOD acting on different vanillate-like substrates; and also revealed that a methoxy group in the meta position and a carboxylic acid moiety in the aromatic ring are key for substrate recognition. Phylogenetic analysis of the oxygenase subunit of bacterial VanODs revealed three divergent groups constituted by homologues found in Proteobacteria (Type I), Actinobacteria (Type II), or Proteobacteria/Actinobacteria (Type III) in which the R1 VanOD is placed. These results suggest that VanOD from R1 strain, and its type III homologues, expand the range of methoxylated aromatics used as substrates by bacteria.
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3
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Zhou W, Alharbi HA, Hummingbird E, Keatinge-Clay AT, Mahmud T. Functional Studies and Revision of the NFAT-133/TM-123 Biosynthetic Pathway in Streptomyces pactum. ACS Chem Biol 2022; 17:2039-2045. [PMID: 35904416 PMCID: PMC9391300 DOI: 10.1021/acschembio.2c00454] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The biosynthetic gene cluster of NFAT-133, an inhibitor of the nuclear factor of activated T cells, was recently identified in Streptomyces pactum ATCC 27456. This cluster is conspicuous by its highly disordered noncollinear type I modular polyketide synthase (PKS) genes that encode PKSs with one module more than those expected for the heptaketide NFAT-133 biosynthesis. Thus, the major metabolite NFAT-133 was proposed to derive from an octaketide analogue, TM-123. Here, we report that further bioinformatic analysis and gene inactivation studies suggest that NFAT-133 is not derived from TM-123 but rather a product of programmed KS7 extension skipping of a nascent heptaketide from the PKS assembly line that produces TM-123. Furthermore, identification of NFAT-133/TM-123 analogues from mutants of the ATCC 27456 strain suggests that NftN (a putative dehydrogenase), NftE (a cytochrome P450), and NftG (a putative hydrolase/decarboxylase) function "in trans" during the polyketide chain assembly processes.
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Affiliation(s)
- Wei Zhou
- Department of Pharmaceutical Sciences, Oregon State University, Corvallis, OR 97331-3507 (USA)
| | - Hattan A. Alharbi
- Department of Pharmaceutical Sciences, Oregon State University, Corvallis, OR 97331-3507 (USA)
| | - Eshe Hummingbird
- Department of Pharmaceutical Sciences, Oregon State University, Corvallis, OR 97331-3507 (USA)
| | | | - Taifo Mahmud
- Department of Pharmaceutical Sciences, Oregon State University, Corvallis, OR 97331-3507 (USA)
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4
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Weiland F, Kohlstedt M, Wittmann C. Guiding stars to the field of dreams: Metabolically engineered pathways and microbial platforms for a sustainable lignin-based industry. Metab Eng 2021; 71:13-41. [PMID: 34864214 DOI: 10.1016/j.ymben.2021.11.011] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 11/25/2021] [Accepted: 11/29/2021] [Indexed: 12/19/2022]
Abstract
Lignin is an important structural component of terrestrial plants and is readily generated during biomass fractionation in lignocellulose processing facilities. Due to lacking alternatives the majority of technical lignins is industrially simply burned into heat and energy. However, regarding its vast abundance and a chemically interesting richness in aromatics, lignin is presently regarded as the most under-utilized and promising feedstock for value-added applications. Notably, microbes have evolved powerful enzymes and pathways that break down lignin and metabolize its various aromatic components. This natural pathway atlas meanwhile serves as a guiding star for metabolic engineers to breed designed cell factories and efficiently upgrade this global waste stream. The metabolism of aromatic compounds, in combination with success stories from systems metabolic engineering, as reviewed here, promises a sustainable product portfolio from lignin, comprising bulk and specialty chemicals, biomaterials, and fuels.
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Affiliation(s)
- Fabia Weiland
- Institute of Systems Biotechnology, Saarland University, Saarbrücken, Germany
| | - Michael Kohlstedt
- Institute of Systems Biotechnology, Saarland University, Saarbrücken, Germany
| | - Christoph Wittmann
- Institute of Systems Biotechnology, Saarland University, Saarbrücken, Germany.
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5
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Tsagogiannis E, Vandera E, Primikyri A, Asimakoula S, Tzakos AG, Gerothanassis IP, Koukkou AI. Characterization of Protocatechuate 4,5-Dioxygenase from Pseudarthrobacter phenanthrenivorans Sphe3 and In Situ Reaction Monitoring in the NMR Tube. Int J Mol Sci 2021; 22:9647. [PMID: 34502555 PMCID: PMC8431788 DOI: 10.3390/ijms22179647] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 08/30/2021] [Accepted: 09/02/2021] [Indexed: 11/16/2022] Open
Abstract
The current study aims at the functional and kinetic characterization of protocatechuate (PCA) 4,5-dioxygenase (PcaA) from Pseudarthrobacter phenanthrenivorans Sphe3. This is the first single subunit Type II dioxygenase characterized in Actinobacteria. RT-PCR analysis demonstrated that pcaA and the adjacent putative genes implicated in the PCA meta-cleavage pathway comprise a single transcriptional unit. The recombinant PcaA is highly specific for PCA and exhibits Michaelis-Menten kinetics with Km and Vmax values of 21 ± 1.6 μM and 44.8 ± 4.0 U × mg-1, respectively, in pH 9.5 and at 20 °C. PcaA also converted gallate from a broad range of substrates tested. The enzymatic reaction products were identified and characterized, for the first time, through in situ biotransformation monitoring inside an NMR tube. The PCA reaction product demonstrated a keto-enol tautomerization, whereas the gallate reaction product was present only in the keto form. Moreover, the transcriptional levels of pcaA and pcaR (gene encoding a LysR-type regulator of the pathway) were also determined, showing an induction when cells were grown on PCA and phenanthrene. Studying key enzymes in biodegradation pathways is significant for bioremediation and for efficient biocatalysts development.
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Affiliation(s)
- Epameinondas Tsagogiannis
- Laboratory of Biochemistry, Sector of Organic Chemistry and Biochemistry, Department of Chemistry, University of Ioannina, 45110 Ioannina, Greece; (E.T.); (E.V.); (S.A.)
| | - Elpiniki Vandera
- Laboratory of Biochemistry, Sector of Organic Chemistry and Biochemistry, Department of Chemistry, University of Ioannina, 45110 Ioannina, Greece; (E.T.); (E.V.); (S.A.)
| | - Alexandra Primikyri
- Laboratory of Organic Chemistry, Sector of Organic Chemistry and Biochemistry, Department of Chemistry, University of Ioannina, 45110 Ioannina, Greece; (A.P.); (A.G.T.); (I.P.G.)
| | - Stamatia Asimakoula
- Laboratory of Biochemistry, Sector of Organic Chemistry and Biochemistry, Department of Chemistry, University of Ioannina, 45110 Ioannina, Greece; (E.T.); (E.V.); (S.A.)
| | - Andreas G. Tzakos
- Laboratory of Organic Chemistry, Sector of Organic Chemistry and Biochemistry, Department of Chemistry, University of Ioannina, 45110 Ioannina, Greece; (A.P.); (A.G.T.); (I.P.G.)
| | - Ioannis P. Gerothanassis
- Laboratory of Organic Chemistry, Sector of Organic Chemistry and Biochemistry, Department of Chemistry, University of Ioannina, 45110 Ioannina, Greece; (A.P.); (A.G.T.); (I.P.G.)
| | - Anna-Irini Koukkou
- Laboratory of Biochemistry, Sector of Organic Chemistry and Biochemistry, Department of Chemistry, University of Ioannina, 45110 Ioannina, Greece; (E.T.); (E.V.); (S.A.)
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6
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Cai C, Xu Z, Zhou H, Chen S, Jin M. Valorization of lignin components into gallate by integrated biological hydroxylation, O-demethylation, and aryl side-chain oxidation. SCIENCE ADVANCES 2021; 7:eabg4585. [PMID: 34516898 PMCID: PMC8442903 DOI: 10.1126/sciadv.abg4585] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Converting lignin components into a single product is a promising way to upgrade lignin. Here, an efficient biocatalyst was developed to selectively produce gallate from lignin components by integrating three main reactions: hydroxylation, O-demethylation, and aryl side-chain oxidation. A rationally designed hydroxylase system was first introduced into a gallate biodegradation pathway–blocked Rhodococcus opacus mutant so that gallate accumulated from protocatechuate and compounds in its upper pathways. Native and heterologous O-demethylation systems were then used, leading to multiple lignin-derived methoxy aromatics being converted to gallate. Furthermore, an aryl side-chain oxidase was engaged to broaden the substrate spectrum. Consequently, the developed biocatalyst showed that gallate yields as high as 0.407 and 0.630 g of gallate per gram of lignin when alkaline-pretreated lignin and base-depolymerized ammonia fiber explosion lignin were applied as substrates, respectively. These results suggested that this rationally developed biocatalyst enabled the lignin valorization process to be simple and efficient.
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Affiliation(s)
- Chenggu Cai
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, 200 Xiaolingwei Street, Nanjing 210094, China
| | - Zhaoxian Xu
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, 200 Xiaolingwei Street, Nanjing 210094, China
| | - Huarong Zhou
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, 200 Xiaolingwei Street, Nanjing 210094, China
| | - Sitong Chen
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, 200 Xiaolingwei Street, Nanjing 210094, China
| | - Mingjie Jin
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, 200 Xiaolingwei Street, Nanjing 210094, China
- Corresponding author.
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7
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Notonier S, Werner AZ, Kuatsjah E, Dumalo L, Abraham PE, Hatmaker EA, Hoyt CB, Amore A, Ramirez KJ, Woodworth SP, Klingeman DM, Giannone RJ, Guss AM, Hettich RL, Eltis LD, Johnson CW, Beckham GT. Metabolism of syringyl lignin-derived compounds in Pseudomonas putida enables convergent production of 2-pyrone-4,6-dicarboxylic acid. Metab Eng 2021; 65:111-122. [PMID: 33741529 DOI: 10.1016/j.ymben.2021.02.005] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Revised: 02/14/2021] [Accepted: 02/22/2021] [Indexed: 12/15/2022]
Abstract
Valorization of lignin, an abundant component of plant cell walls, is critical to enabling the lignocellulosic bioeconomy. Biological funneling using microbial biocatalysts has emerged as an attractive approach to convert complex mixtures of lignin depolymerization products to value-added compounds. Ideally, biocatalysts would convert aromatic compounds derived from the three canonical types of lignin: syringyl (S), guaiacyl (G), and p-hydroxyphenyl (H). Pseudomonas putida KT2440 (hereafter KT2440) has been developed as a biocatalyst owing in part to its native catabolic capabilities but is not known to catabolize S-type lignin-derived compounds. Here, we demonstrate that syringate, a common S-type lignin-derived compound, is utilized by KT2440 only in the presence of another energy source or when vanAB was overexpressed, as syringate was found to be O-demethylated to gallate by VanAB, a two-component monooxygenase, and further catabolized via extradiol cleavage. Unexpectedly, the specificity (kcat/KM) of VanAB for syringate was within 25% that for vanillate and O-demethylation of both substrates was well-coupled to O2 consumption. However, the native KT2440 gallate-cleaving dioxygenase, GalA, was potently inactivated by 3-O-methylgallate. To engineer a biocatalyst to simultaneously convert S-, G-, and H-type monomers, we therefore employed VanAB from Pseudomonas sp. HR199, which has lower activity for 3MGA, and LigAB, an extradiol dioxygenase able to cleave protocatechuate and 3-O-methylgallate. This strain converted 93% of a mixture of lignin monomers to 2-pyrone-4,6-dicarboxylate, a promising bio-based chemical. Overall, this study elucidates a native pathway in KT2440 for catabolizing S-type lignin-derived compounds and demonstrates the potential of this robust chassis for lignin valorization.
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Affiliation(s)
- Sandra Notonier
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA; Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN, 37830, USA
| | - Allison Z Werner
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA; Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN, 37830, USA
| | - Eugene Kuatsjah
- Department of Microbiology and Immunology, BioProducts Institute, and the Life Sciences Institute, The University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Linda Dumalo
- Department of Microbiology and Immunology, BioProducts Institute, and the Life Sciences Institute, The University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Paul E Abraham
- Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN, 37830, USA; Oak Ridge National Laboratory, 1 Bethel Valley Rd, Oak Ridge, TN, 37830, USA
| | - E Anne Hatmaker
- Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN, 37830, USA; Oak Ridge National Laboratory, 1 Bethel Valley Rd, Oak Ridge, TN, 37830, USA
| | - Caroline B Hoyt
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA
| | - Antonella Amore
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA
| | - Kelsey J Ramirez
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA
| | - Sean P Woodworth
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA
| | - Dawn M Klingeman
- Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN, 37830, USA; Oak Ridge National Laboratory, 1 Bethel Valley Rd, Oak Ridge, TN, 37830, USA
| | - Richard J Giannone
- Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN, 37830, USA; Oak Ridge National Laboratory, 1 Bethel Valley Rd, Oak Ridge, TN, 37830, USA
| | - Adam M Guss
- Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN, 37830, USA; Oak Ridge National Laboratory, 1 Bethel Valley Rd, Oak Ridge, TN, 37830, USA
| | - Robert L Hettich
- Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN, 37830, USA; Oak Ridge National Laboratory, 1 Bethel Valley Rd, Oak Ridge, TN, 37830, USA
| | - Lindsay D Eltis
- Department of Microbiology and Immunology, BioProducts Institute, and the Life Sciences Institute, The University of British Columbia, Vancouver, BC V6T 1Z3, Canada.
| | - Christopher W Johnson
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA.
| | - Gregg T Beckham
- Renewable Resources and Enabling Sciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA; Center for Bioenergy Innovation, Oak Ridge National Laboratory, Oak Ridge, TN, 37830, USA.
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8
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Kumar M, You S, Beiyuan J, Luo G, Gupta J, Kumar S, Singh L, Zhang S, Tsang DCW. Lignin valorization by bacterial genus Pseudomonas: State-of-the-art review and prospects. BIORESOURCE TECHNOLOGY 2021; 320:124412. [PMID: 33249259 DOI: 10.1016/j.biortech.2020.124412] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Revised: 11/08/2020] [Accepted: 11/11/2020] [Indexed: 06/12/2023]
Abstract
The most prominent aromatic feedstock on Earth is lignin, however, lignin valorization is still an underrated subject. The principal preparatory strategies for lignin valorization are fragmentation and depolymerization which help in the production of fuels and chemicals. Owing to lignin's structural heterogeneity, these strategies result in product generation which requires tedious separation and purification to extract target products. The bacterial genus Pseudomonas has been dominant for its lignin valorization potency, owing to a robust enzymatic machinery that is used to funnel variable lignin derivatives into certain target products such as polyhydroxyalkanotes (PHAs) and cis, cis-muconic acid (MA). In this review, the potential of genus Pseudomonas in lignin valorization is critically reviewed along with the advanced genetic techniques and tools to ease the use of lignin/lignin-model compounds for the synthesis of bioproducts. This review also highlights the research gaps in lignin biovalorization and discuss the challenges and possibilities for future research.
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Affiliation(s)
- Manish Kumar
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China; CSIR - National Environmental and Engineering Research Institute (CSIR-NEERI), Nagpur 440 020, India
| | - Siming You
- University of Glasgow, James Watt School of Engineering, Glasgow G12 8 QQ, United Kingdom
| | - Jingzi Beiyuan
- Biochar Engineering Technology Research Center of Guangdong Province, School of Environment and Chemical Engineering, Foshan University, Foshan 528000, China
| | - Gang Luo
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Juhi Gupta
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Sunil Kumar
- CSIR - National Environmental and Engineering Research Institute (CSIR-NEERI), Nagpur 440 020, India
| | - Lal Singh
- CSIR - National Environmental and Engineering Research Institute (CSIR-NEERI), Nagpur 440 020, India
| | - Shicheng Zhang
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3), Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Daniel C W Tsang
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China.
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9
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Zhou W, Posri P, Abugrain ME, Weisberg AJ, Chang JH, Mahmud T. Biosynthesis of the Nuclear Factor of Activated T Cells Inhibitor NFAT-133 in Streptomyces pactum. ACS Chem Biol 2020; 15:3217-3226. [PMID: 33284588 DOI: 10.1021/acschembio.0c00775] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
NFAT-133 is a Streptomyces-derived aromatic polyketide compound with immunosuppressive, antidiabetic, and antitrypanosomal activities. It inhibits transcription mediated by nuclear factor of activated T cells (NFAT), leading to the suppression of interleukin-2 expression and T cell proliferation. It also activates the AMPK pathway in L6 myotubes and increases glucose uptake. In addition to NFAT-133, a number of its congeners, e.g., panowamycins and benwamycins, have been identified. However, little is known about their modes of formation in the producing organisms. Through genome sequencing of Streptomyces pactum ATCC 27456, gene inactivation, and genetic complementation experiments, the biosynthetic gene cluster of NFAT-133 and its congeners has been identified. The cluster contains a highly disordered genetic organization of type I modular polyketide synthase genes with several genes that are necessary for the formation of the aromatic core unit and tailoring processes. In addition, a number of new analogs of NFAT-133 were isolated and their chemical structures elucidated. It is suggested that the heptaketide NFAT-133 is derived from an octaketide intermediate, TM-123. The current study shows yet another unusual biosynthetic pathway involving a noncanonical polyketide synthase assembly line to produce a group of small molecules with valuable bioactivities.
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10
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Li N, Peng Q, Yao L, He Q, Qiu J, Cao H, He J, Niu Q, Lu Y, Hui F. Roles of the Gentisate 1,2-Dioxygenases DsmD and GtdA in the Catabolism of the Herbicide Dicamba in Rhizorhabdus dicambivorans Ndbn-20. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:9287-9298. [PMID: 32786824 DOI: 10.1021/acs.jafc.0c01523] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
3-Chlorogentisate is a key intermediate in the catabolism of the herbicide dicamba in R. dicambivorans Ndbn-20. In this study, we identified two gentisate 1,2-dioxygenases (GDOs), DsmD and GtdA, from Ndbn-20. The amino acid sequence similarity between DsmD and GtdA is 51%. Both of them are dimers and showed activities to gentisate and 3-chlorogentisate but not 3,6-dichlorogentisate (3,6-DCGA) or 6-chlorogentisate in vitro. The kcat/Km of DsmD for 3-chlorogentisate was 28.7 times higher than that of GtdA, whereas the kcat/Km of DsmD for gentisate was only one-fourth of that of GtdA. Transcription of dsmD was dramatically induced by 3-chlorogentisate but not gentisate, whereas gtdA was not induced. Disruption of dsmD resulted in a significant decline in the degradation rates of 3-chlorogentisate and dicamba but had no effect on the degradation of gentisate, whereas the result of disruption of gtdA was converse; the disruption of both dsmD and gtdA led to the inability to degrade 3-chlorogentisate and gentisate. This study revealed that 3-chlorogentisate but not gentisate or 3,6-DCGA is the ring-cleavage substrate in the dicamba degradation pathway in R. dicambivorans Ndbn-20; DsmD is specifically responsible for cleavage of 3-chlorogentisate, whereas GtdA is a general GDO involved in the catabolism of various natural aromatic compounds.
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Affiliation(s)
- Na Li
- School of Life Science and Technology, Nanyang Normal University, Nanyang, Henan 473061, China
| | - Qian Peng
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China
| | - Li Yao
- School of Marine and Biological Engineering, Yancheng Teachers University, Yancheng, Jiangsu 224002, China
| | - Qin He
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China
| | - Jiguo Qiu
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China
| | - Hui Cao
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China
| | - Jian He
- Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture, College of Life Sciences, Nanjing Agricultural University, Nanjing, Jiangsu 210095, China
| | - Qiuhong Niu
- School of Life Science and Technology, Nanyang Normal University, Nanyang, Henan 473061, China
| | - Yunfeng Lu
- School of Life Science and Technology, Nanyang Normal University, Nanyang, Henan 473061, China
- State Key Laboratory of Motor Vehicle Biofuel Technology, Nanyang, Henan 473000, China
| | - Fengli Hui
- School of Life Science and Technology, Nanyang Normal University, Nanyang, Henan 473061, China
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11
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Phale PS, Malhotra H, Shah BA. Degradation strategies and associated regulatory mechanisms/features for aromatic compound metabolism in bacteria. ADVANCES IN APPLIED MICROBIOLOGY 2020; 112:1-65. [PMID: 32762865 DOI: 10.1016/bs.aambs.2020.02.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
As a result of anthropogenic activity, large number of recalcitrant aromatic compounds have been released into the environment. Consequently, microbial communities have adapted and evolved to utilize these compounds as sole carbon source, under both aerobic and anaerobic conditions. The constitutive expression of enzymes necessary for metabolism imposes a heavy energy load on the microbe which is overcome by arrangement of degradative genes as operons which are induced by specific inducers. The segmentation of pathways into upper, middle and/or lower operons has allowed microbes to funnel multiple compounds into common key aromatic intermediates which are further metabolized through central carbon pathway. Various proteins belonging to diverse families have evolved to regulate the transcription of individual operons participating in aromatic catabolism. These proteins, complemented with global regulatory mechanisms, carry out the regulation of aromatic compound metabolic pathways in a concerted manner. Additionally, characteristics like chemotaxis, preferential utilization, pathway compartmentalization and biosurfactant production confer an advantage to the microbe, thus making bioremediation of the aromatic pollutants more efficient and effective.
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Affiliation(s)
- Prashant S Phale
- Department of Biosciences and Bioengineering, Indian Institute of Technology-Bombay, Mumbai, India.
| | - Harshit Malhotra
- Department of Biosciences and Bioengineering, Indian Institute of Technology-Bombay, Mumbai, India
| | - Bhavik A Shah
- Department of Biosciences and Bioengineering, Indian Institute of Technology-Bombay, Mumbai, India
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12
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Becker J, Wittmann C. A field of dreams: Lignin valorization into chemicals, materials, fuels, and health-care products. Biotechnol Adv 2019; 37:107360. [DOI: 10.1016/j.biotechadv.2019.02.016] [Citation(s) in RCA: 207] [Impact Index Per Article: 41.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 02/18/2019] [Accepted: 02/22/2019] [Indexed: 02/07/2023]
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13
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Shinoda E, Takahashi K, Abe N, Kamimura N, Sonoki T, Masai E. Isolation of a novel platform bacterium for lignin valorization and its application in glucose-free cis,cis-muconate production. ACTA ACUST UNITED AC 2019; 46:1071-1080. [DOI: 10.1007/s10295-019-02190-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 05/20/2019] [Indexed: 01/28/2023]
Abstract
Abstract
Microbial production of cis,cis-muconate (ccMA) from phenolic compounds obtained by chemical depolymerization of lignin is a promising approach to valorize lignin. Because microbial production requires a large amount of carbon and energy source, it is desirable to establish a ccMA-producing strain that utilizes lignin-derived phenols instead of general sources like glucose. We isolated Pseudomonas sp. strain NGC7 that grows well on various phenolic compounds derived from p-hydroxyphenyl, guaiacyl, and syringyl units of lignin. An NGC7 mutant of protocatechuate (PCA) 3,4-dioxygenase and ccMA cycloisomerase genes (NGC703) lost the ability to grow on vanillate and p-hydroxybenzoate but grew normally on syringate. Introduction of a plasmid carrying genes encoding PCA decarboxylase, flavin prenyltransferase, vanillate O-demethylase, and catechol 1,2-dioxygenase into NGC703 enabled production of 3.2 g/L ccMA from vanillate with a yield of 75% while growing on syringate. This strain also produced ccMA from birch lignin-derived phenols. All these results indicate the utility of NGC7 in glucose-free ccMA production.
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Affiliation(s)
- Eri Shinoda
- 0000 0001 0671 2234 grid.260427.5 Department of Bioengineering Nagaoka University of Technology Kamitomioka 940-2188 Nagaoka Niigata Japan
| | - Kenji Takahashi
- 0000 0001 0671 2234 grid.260427.5 Department of Bioengineering Nagaoka University of Technology Kamitomioka 940-2188 Nagaoka Niigata Japan
| | - Nanase Abe
- 0000 0001 0671 2234 grid.260427.5 Department of Bioengineering Nagaoka University of Technology Kamitomioka 940-2188 Nagaoka Niigata Japan
| | - Naofumi Kamimura
- 0000 0001 0671 2234 grid.260427.5 Department of Bioengineering Nagaoka University of Technology Kamitomioka 940-2188 Nagaoka Niigata Japan
| | - Tomonori Sonoki
- 0000 0001 0673 6172 grid.257016.7 Faculty of Agriculture and Life Science Hirosaki University 036-8561 Hirosaki Aomori Japan
| | - Eiji Masai
- 0000 0001 0671 2234 grid.260427.5 Department of Bioengineering Nagaoka University of Technology Kamitomioka 940-2188 Nagaoka Niigata Japan
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14
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Burroughs AM, Glasner ME, Barry KP, Taylor EA, Aravind L. Oxidative opening of the aromatic ring: Tracing the natural history of a large superfamily of dioxygenase domains and their relatives. J Biol Chem 2019; 294:10211-10235. [PMID: 31092555 PMCID: PMC6664185 DOI: 10.1074/jbc.ra119.007595] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 05/09/2019] [Indexed: 12/20/2022] Open
Abstract
A diverse collection of enzymes comprising the protocatechuate dioxygenases (PCADs) has been characterized in several extradiol aromatic compound degradation pathways. Structural studies have shown a relationship between PCADs and the more broadly-distributed, functionally enigmatic Memo domain linked to several human diseases. To better understand the evolution of this PCAD-Memo protein superfamily, we explored their structural and functional determinants to establish a unified evolutionary framework, identifying 15 clearly-delineable families, including a previously-underappreciated diversity in five Memo clade families. We place the superfamily's origin within the greater radiation of the nucleoside phosphorylase/hydrolase-peptide/amidohydrolase fold prior to the last universal common ancestor of all extant organisms. In addition to identifying active-site residues across the superfamily, we describe three distinct, structurally-variable regions emanating from the core scaffold often housing conserved residues specific to individual families. These were predicted to contribute to the active-site pocket, potentially in substrate specificity and allosteric regulation. We also identified several previously-undescribed conserved genome contexts, providing insight into potentially novel substrates in PCAD clade families. We extend known conserved contextual associations for the Memo clade beyond previously-described associations with the AMMECR1 domain and a radical S-adenosylmethionine family domain. These observations point to two distinct yet potentially overlapping contexts wherein the elusive molecular function of the Memo domain could be finally resolved, thereby linking it to nucleotide base and aliphatic isoprenoid modification. In total, this report throws light on the functions of large swaths of the experimentally-uncharacterized PCAD-Memo families.
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Affiliation(s)
- A Maxwell Burroughs
- From the Computational Biology Branch, NCBI, National Library of Medicine, National Institutes of Health, Bethesda, Maryland 20894
| | - Margaret E Glasner
- the Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas 77843, and
| | - Kevin P Barry
- the Department of Chemistry, Wesleyan University, Middletown, Connecticut 06459
| | - Erika A Taylor
- the Department of Chemistry, Wesleyan University, Middletown, Connecticut 06459
| | - L Aravind
- From the Computational Biology Branch, NCBI, National Library of Medicine, National Institutes of Health, Bethesda, Maryland 20894,
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15
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Lubbers RJM, Dilokpimol A, Visser J, Mäkelä MR, Hildén KS, de Vries RP. A comparison between the homocyclic aromatic metabolic pathways from plant-derived compounds by bacteria and fungi. Biotechnol Adv 2019; 37:107396. [PMID: 31075306 DOI: 10.1016/j.biotechadv.2019.05.002] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Revised: 04/18/2019] [Accepted: 05/03/2019] [Indexed: 12/13/2022]
Abstract
Aromatic compounds derived from lignin are of great interest for renewable biotechnical applications. They can serve in many industries e.g. as biochemical building blocks for bioplastics or biofuels, or as antioxidants, flavor agents or food preservatives. In nature, lignin is degraded by microorganisms, which results in the release of homocyclic aromatic compounds. Homocyclic aromatic compounds can also be linked to polysaccharides, tannins and even found freely in plant biomass. As these compounds are often toxic to microbes already at low concentrations, they need to be degraded or converted to less toxic forms. Prior to ring cleavage, the plant- and lignin-derived aromatic compounds are converted to seven central ring-fission intermediates, i.e. catechol, protocatechuic acid, hydroxyquinol, hydroquinone, gentisic acid, gallic acid and pyrogallol through complex aromatic metabolic pathways and used as energy source in the tricarboxylic acid cycle. Over the decades, bacterial aromatic metabolism has been described in great detail. However, the studies on fungal aromatic pathways are scattered over different pathways and species, complicating a comprehensive view of fungal aromatic metabolism. In this review, we depicted the similarities and differences of the reported aromatic metabolic pathways in fungi and bacteria. Although both microorganisms share the main conversion routes, many alternative pathways are observed in fungi. Understanding the microbial aromatic metabolic pathways could lead to metabolic engineering for strain improvement and promote valorization of lignin and related aromatic compounds.
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Affiliation(s)
- Ronnie J M Lubbers
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands.
| | - Adiphol Dilokpimol
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands.
| | - Jaap Visser
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands.
| | - Miia R Mäkelä
- Department of Microbiology, University of Helsinki, Viikinkaari 9, Helsinki, Finland.
| | - Kristiina S Hildén
- Department of Microbiology, University of Helsinki, Viikinkaari 9, Helsinki, Finland.
| | - Ronald P de Vries
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands; Department of Microbiology, University of Helsinki, Viikinkaari 9, Helsinki, Finland.
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16
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Mallinson SJB, Machovina MM, Silveira RL, Garcia-Borràs M, Gallup N, Johnson CW, Allen MD, Skaf MS, Crowley MF, Neidle EL, Houk KN, Beckham GT, DuBois JL, McGeehan JE. A promiscuous cytochrome P450 aromatic O-demethylase for lignin bioconversion. Nat Commun 2018; 9:2487. [PMID: 29950589 PMCID: PMC6021390 DOI: 10.1038/s41467-018-04878-2] [Citation(s) in RCA: 107] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Accepted: 05/26/2018] [Indexed: 11/18/2022] Open
Abstract
Microbial aromatic catabolism offers a promising approach to convert lignin, a vast source of renewable carbon, into useful products. Aryl-O-demethylation is an essential biochemical reaction to ultimately catabolize coniferyl and sinapyl lignin-derived aromatic compounds, and is often a key bottleneck for both native and engineered bioconversion pathways. Here, we report the comprehensive characterization of a promiscuous P450 aryl-O-demethylase, consisting of a cytochrome P450 protein from the family CYP255A (GcoA) and a three-domain reductase (GcoB) that together represent a new two-component P450 class. Though originally described as converting guaiacol to catechol, we show that this system efficiently demethylates both guaiacol and an unexpectedly wide variety of lignin-relevant monomers. Structural, biochemical, and computational studies of this novel two-component system elucidate the mechanism of its broad substrate specificity, presenting it as a new tool for a critical step in biological lignin conversion.
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Affiliation(s)
- Sam J B Mallinson
- Molecular Biophysics, School of Biological Sciences, Institute of Biological and Biomedical Sciences, University of Portsmouth, Portsmouth, PO1 2DY, UK
| | - Melodie M Machovina
- National Bioenergy Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT, 59717, USA
| | - Rodrigo L Silveira
- National Bioenergy Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA
- Institute of Chemistry, University of Campinas, Campinas, Sao Paulo, 13083-970, Brazil
| | - Marc Garcia-Borràs
- Department of Chemistry and Biochemistry, University of California at Los Angeles, Los Angeles, CA, 90095, USA
| | - Nathan Gallup
- National Bioenergy Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA
- Department of Chemistry and Biochemistry, University of California at Los Angeles, Los Angeles, CA, 90095, USA
| | - Christopher W Johnson
- National Bioenergy Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA
| | - Mark D Allen
- Molecular Biophysics, School of Biological Sciences, Institute of Biological and Biomedical Sciences, University of Portsmouth, Portsmouth, PO1 2DY, UK
| | - Munir S Skaf
- Institute of Chemistry, University of Campinas, Campinas, Sao Paulo, 13083-970, Brazil
| | - Michael F Crowley
- Biosciences Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA
| | - Ellen L Neidle
- Department of Microbiology, University of Georgia, Athens, GA, 30602, USA
| | - Kendall N Houk
- Department of Chemistry and Biochemistry, University of California at Los Angeles, Los Angeles, CA, 90095, USA.
| | - Gregg T Beckham
- National Bioenergy Center, National Renewable Energy Laboratory, Golden, CO, 80401, USA.
| | - Jennifer L DuBois
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT, 59717, USA.
| | - John E McGeehan
- Molecular Biophysics, School of Biological Sciences, Institute of Biological and Biomedical Sciences, University of Portsmouth, Portsmouth, PO1 2DY, UK.
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17
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Hogancamp TN, Raushel FM. Functional Annotation of LigU as a 1,3-Allylic Isomerase during the Degradation of Lignin in the Protocatechuate 4,5-Cleavage Pathway from the Soil Bacterium Sphingobium sp. SYK-6. Biochemistry 2018; 57:2837-2845. [DOI: 10.1021/acs.biochem.8b00295] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Tessily N. Hogancamp
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Frank M. Raushel
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
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18
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Kamimura N, Takahashi K, Mori K, Araki T, Fujita M, Higuchi Y, Masai E. Bacterial catabolism of lignin-derived aromatics: New findings in a recent decade: Update on bacterial lignin catabolism. ENVIRONMENTAL MICROBIOLOGY REPORTS 2017; 9:679-705. [PMID: 29052962 DOI: 10.1111/1758-2229.12597] [Citation(s) in RCA: 160] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Revised: 09/26/2017] [Accepted: 10/03/2017] [Indexed: 05/21/2023]
Abstract
Lignin is the most abundant phenolic polymer; thus, its decomposition by microorganisms is fundamental to carbon cycling on earth. Lignin breakdown is initiated by depolymerization catalysed by extracellular oxidoreductases secreted by white-rot basidiomycetous fungi. On the other hand, bacteria play a predominant role in the mineralization of lignin-derived heterogeneous low-molecular-weight aromatic compounds. The outline of bacterial catabolic pathways for lignin-derived bi- and monoaryls are typically composed of the following sequential steps: (i) funnelling of a wide variety of lignin-derived aromatics into vanillate and syringate, (ii) O demethylation of vanillate and syringate to form catecholic derivatives and (iii) aromatic ring-cleavage of the catecholic derivatives to produce tricarboxylic acid cycle intermediates. Knowledge regarding bacterial catabolic systems for lignin-derived aromatic compounds is not only important for understanding the terrestrial carbon cycle but also valuable for promoting the shift to a low-carbon economy via biological lignin valorisation. This review summarizes recent progress in bacterial catabolic systems for lignin-derived aromatic compounds, including newly identified catabolic pathways and genes for decomposition of lignin-derived biaryls, transcriptional regulation and substrate uptake systems. Recent omics approaches on catabolism of lignin-derived aromatic compounds are also described.
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Affiliation(s)
- Naofumi Kamimura
- Department of Bioengineering, Nagaoka University of Technology, Nagaoka, Niigata 940-2188, Japan
| | - Kenji Takahashi
- Department of Bioengineering, Nagaoka University of Technology, Nagaoka, Niigata 940-2188, Japan
| | - Kosuke Mori
- Department of Bioengineering, Nagaoka University of Technology, Nagaoka, Niigata 940-2188, Japan
| | - Takuma Araki
- Department of Bioengineering, Nagaoka University of Technology, Nagaoka, Niigata 940-2188, Japan
| | - Masaya Fujita
- Department of Bioengineering, Nagaoka University of Technology, Nagaoka, Niigata 940-2188, Japan
| | - Yudai Higuchi
- Department of Bioengineering, Nagaoka University of Technology, Nagaoka, Niigata 940-2188, Japan
| | - Eiji Masai
- Department of Bioengineering, Nagaoka University of Technology, Nagaoka, Niigata 940-2188, Japan
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19
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Mazurkewich S, Seah SYK. Investigation into the Mode of Phosphate Activation in the 4-Hydroxy-4-Methyl-2-Oxoglutarate/4-Carboxy-4-Hydroxy-2-Oxoadipate Aldolase from Pseudomonas putida F1. PLoS One 2016; 11:e0164556. [PMID: 27741265 PMCID: PMC5065237 DOI: 10.1371/journal.pone.0164556] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Accepted: 09/03/2016] [Indexed: 11/18/2022] Open
Abstract
The 4-hydroxy-4-methyl-2-oxoglutarate (HMG)/4-carboxy-4-hydroxy-2-oxoadipate (CHA) aldolase is the last enzyme of both the gallate and protocatechuate 4,5-cleavage pathways which links aromatic catabolism to central cellular metabolism. The enzyme is a class II, divalent metal dependent, aldolase which is activated in the presence of inorganic phosphate (Pi), increasing its turnover rate >10-fold. This phosphate activation is unique for a class II aldolase. The aldolase pyruvate methyl proton exchange rate, a probe of the general acid half reaction, was increased 300-fold in the presence of 1 mM Pi and the rate enhancement followed saturation kinetics giving rise to a KM of 397 ± 30 μM. Docking studies revealed a potential Pi binding site close to, or overlapping with, the proposed general acid water site. Putative Pi binding residues were substituted by site-directed mutagenesis which resulted in reductions of Pi activation. Significantly, the active site residue Arg-123, known to be critical for the catalytic mechanism of the enzyme, was also implicated in supporting Pi mediated activation.
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Affiliation(s)
- Scott Mazurkewich
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
| | - Stephen Y. K. Seah
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
- * E-mail:
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20
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Belda E, van Heck RGA, José Lopez-Sanchez M, Cruveiller S, Barbe V, Fraser C, Klenk HP, Petersen J, Morgat A, Nikel PI, Vallenet D, Rouy Z, Sekowska A, Martins dos Santos VAP, de Lorenzo V, Danchin A, Médigue C. The revisited genome ofPseudomonas putidaKT2440 enlightens its value as a robust metabolicchassis. Environ Microbiol 2016; 18:3403-3424. [DOI: 10.1111/1462-2920.13230] [Citation(s) in RCA: 217] [Impact Index Per Article: 27.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Accepted: 01/16/2016] [Indexed: 01/08/2023]
Affiliation(s)
- Eugeni Belda
- Alternative Energies and Atomic Energy Commission (CEA), Genomic Institute & CNRS-UMR8030 & Evry University, Laboratory of Bioinformatics Analysis in Genomics and Metabolism; 2 rue Gaston Crémieux 91057 Evry France
- Institut Pasteur, Unit of Insect Vector Genetics and Genomics, Department of Parasitology and Mycology; 28, rue du Dr. Roux, Paris, Cedex 15 75724 France
| | - Ruben G. A. van Heck
- Laboratory of Systems and Synthetic Biology, Wageningen University; Dreijenplein 10, Building number 316 6703 HB Wageningen The Netherlands
| | - Maria José Lopez-Sanchez
- Alternative Energies and Atomic Energy Commission (CEA), Genomic Institute & CNRS-UMR8030 & Evry University, Laboratory of Bioinformatics Analysis in Genomics and Metabolism; 2 rue Gaston Crémieux 91057 Evry France
- AMAbiotics SAS, Institut du Cerveau et de la Moëlle Épinière, Hôpital de la Pitié-Salpêtrière; Paris France
| | - Stéphane Cruveiller
- Alternative Energies and Atomic Energy Commission (CEA), Genomic Institute & CNRS-UMR8030 & Evry University, Laboratory of Bioinformatics Analysis in Genomics and Metabolism; 2 rue Gaston Crémieux 91057 Evry France
| | - Valérie Barbe
- Alternative Energies and Atomic Energy Commission (CEA), Genomic Institute, National Sequencing Center; 2 rue Gaston Crémieux 91057 Evry France
| | - Claire Fraser
- Institute for Genome Sciences, Department of Microbiology and Immunology, University of Maryland School of Medicine; Baltimore MD USA
| | - Hans-Peter Klenk
- Leibniz Institute DSMZ - German Collection of Microorganisms and Cell Cultures; Braunschweig Germany
- School of Biology, Newcastle University; Newcastle upon Tyne NE1 7RU UK
| | - Jörn Petersen
- Leibniz Institute DSMZ - German Collection of Microorganisms and Cell Cultures; Braunschweig Germany
| | - Anne Morgat
- Swiss-Prot Group, SIB Swiss Institute of Bioinformatics; Geneva CH-1206 Switzerland
| | - Pablo I. Nikel
- Systems and Synthetic Biology Program, Centro Nacional de Biotecnología (CNB-CSIC); C/Darwin 3 28049 Madrid Spain
| | - David Vallenet
- Alternative Energies and Atomic Energy Commission (CEA), Genomic Institute & CNRS-UMR8030 & Evry University, Laboratory of Bioinformatics Analysis in Genomics and Metabolism; 2 rue Gaston Crémieux 91057 Evry France
| | - Zoé Rouy
- Alternative Energies and Atomic Energy Commission (CEA), Genomic Institute & CNRS-UMR8030 & Evry University, Laboratory of Bioinformatics Analysis in Genomics and Metabolism; 2 rue Gaston Crémieux 91057 Evry France
| | - Agnieszka Sekowska
- AMAbiotics SAS, Institut du Cerveau et de la Moëlle Épinière, Hôpital de la Pitié-Salpêtrière; Paris France
| | - Vitor A. P. Martins dos Santos
- Laboratory of Systems and Synthetic Biology, Wageningen University; Dreijenplein 10, Building number 316 6703 HB Wageningen The Netherlands
| | - Víctor de Lorenzo
- Systems and Synthetic Biology Program, Centro Nacional de Biotecnología (CNB-CSIC); C/Darwin 3 28049 Madrid Spain
| | - Antoine Danchin
- AMAbiotics SAS, Institut du Cerveau et de la Moëlle Épinière, Hôpital de la Pitié-Salpêtrière; Paris France
| | - Claudine Médigue
- Alternative Energies and Atomic Energy Commission (CEA), Genomic Institute & CNRS-UMR8030 & Evry University, Laboratory of Bioinformatics Analysis in Genomics and Metabolism; 2 rue Gaston Crémieux 91057 Evry France
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21
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Functional Metagenomics of a Biostimulated Petroleum-Contaminated Soil Reveals an Extraordinary Diversity of Extradiol Dioxygenases. Appl Environ Microbiol 2016; 82:2467-2478. [PMID: 26896130 DOI: 10.1128/aem.03811-15] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 01/19/2016] [Indexed: 12/26/2022] Open
Abstract
A metagenomic library of a petroleum-contaminated soil was constructed in a fosmid vector that allowed heterologous expression of metagenomic DNA. The library, consisting of 6.5 Gb of metagenomic DNA, was screened for extradiol dioxygenase (Edo) activity using catechol and 2,3-dihydroxybiphenyl as the substrates. Fifty-eight independent clones encoding extradiol dioxygenase activity were identified. Forty-one different Edo-encoding genes were identified. The population of Edo genes was not dominated by a particular gene or by highly similar genes; rather, the genes had an even distribution and high diversity. Phylogenetic analyses revealed that most of the genes could not be ascribed to previously defined subfamilies of Edos. Rather, the Edo genes led to the definition of 10 new subfamilies of type I Edos. Phylogenetic analysis of type II enzymes defined 7 families, 2 of which harbored the type II Edos that were found in this work. Particularly striking was the diversity found in family I.3 Edos; 15 out of the 17 sequences assigned to this family belonged to 7 newly defined subfamilies. A strong bias was found that depended on the substrate used for the screening: catechol mainly led to the detection of Edos belonging to the I.2 family, while 2,3-dihydroxybiphenyl led to the detection of most other Edos. Members of the I.2 family showed a clear substrate preference for monocyclic substrates, while those from the I.3 family showed a broader substrate range and high activity toward 2,3-dihydroxybiphenyl. This metagenomic analysis has substantially increased our knowledge of the existing biodiversity of Edos.
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22
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Mazurkewich S, Brott AS, Kimber MS, Seah SYK. Structural and Kinetic Characterization of the 4-Carboxy-2-hydroxymuconate Hydratase from the Gallate and Protocatechuate 4,5-Cleavage Pathways of Pseudomonas putida KT2440. J Biol Chem 2016; 291:7669-86. [PMID: 26867578 PMCID: PMC4817193 DOI: 10.1074/jbc.m115.682054] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 02/03/2016] [Indexed: 11/06/2022] Open
Abstract
The bacterial catabolism of lignin and its breakdown products is of interest for applications in industrial processing of ligno-biomass. The gallate degradation pathway ofPseudomonas putidaKT2440 requires a 4-carboxy-2-hydroxymuconate (CHM) hydratase (GalB), which has a 12% sequence identity to a previously identified CHM hydratase (LigJ) fromSphingomonassp. SYK-6. The structure of GalB was determined and found to be a member of the PIG-LN-acetylglucosamine deacetylase family; GalB is structurally distinct from the amidohydrolase fold of LigJ. LigJ has the same stereospecificity as GalB, providing an example of convergent evolution for catalytic conversion of a common metabolite in bacterial aromatic degradation pathways. Purified GalB contains a bound Zn(2+)cofactor; however the enzyme is capable of using Fe(2+)and Co(2+)with similar efficiency. The general base aspartate in the PIG-L deacetylases is an alanine in GalB; replacement of the alanine with aspartate decreased the GalB catalytic efficiency for CHM by 9.5 × 10(4)-fold, and the variant enzyme did not have any detectable hydrolase activity. Kinetic analyses and pH dependence studies of the wild type and variant enzymes suggested roles for Glu-48 and His-164 in the catalytic mechanism. A comparison with the PIG-L deacetylases led to a proposed mechanism for GalB wherein Glu-48 positions and activates the metal-ligated water for the hydration reaction and His-164 acts as a catalytic acid.
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Affiliation(s)
- Scott Mazurkewich
- From the Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Ashley S Brott
- From the Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Matthew S Kimber
- From the Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Stephen Y K Seah
- From the Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
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23
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Xie XG, Huang CY, Fu WQ, Dai CC. Potential of endophytic fungus Phomopsis liquidambari for transformation and degradation of recalcitrant pollutant sinapic acid. Fungal Biol 2015; 120:402-13. [PMID: 26895869 DOI: 10.1016/j.funbio.2015.11.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2015] [Revised: 11/06/2015] [Accepted: 11/29/2015] [Indexed: 11/20/2022]
Abstract
The biodegradation potential of sinapic acid, one of the most representative methoxy phenolic pollutants presented in industrial wastewater, was first studied using an endophytic fungus called Phomopsis liquidambari. This strain can effectively degrade sinapic acid in flasks and in soil and the possible biodegradation pathway was first systematically proposed on the basis of the metabolite production patterns and the identification of the metabolites by GC-MS and HPLC-MS. Sinapic acid was first transformed to 2,6-dimethoxy-4-vinylphenol that was further degraded via 4-hydroxy-3,5-dimethoxybenzaldehyde, syringic acid, gallic acid, and citric acid which involved in the continuous catalysis by phenolic acid decarboxylase, laccase, and gallic acid dioxygenase. Moreover, their activities and gene expression levels exhibited a 'cascade induction' response with the changes in metabolic product concentrations and the generation of fungal laccase significantly improved the degradation process. This study is the first report of an endophytic fungus that has great potential to degrade xenobiotic sinapic acid, and also provide a basis for practical application of endophytic fungus in the bioremediation of sinapic acid-contaminated industrial wastewater and soils.
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Affiliation(s)
- Xing-Guang Xie
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Sciences, Nanjing Normal University, No. 1 Wenyuan Road, Nanjing, Jiangsu Province, 210023, China
| | - Chun-Yan Huang
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Sciences, Nanjing Normal University, No. 1 Wenyuan Road, Nanjing, Jiangsu Province, 210023, China
| | - Wan-Qiu Fu
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Sciences, Nanjing Normal University, No. 1 Wenyuan Road, Nanjing, Jiangsu Province, 210023, China
| | - Chuan-Chao Dai
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Center for Industrialization of Microbial Resources, College of Life Sciences, Nanjing Normal University, No. 1 Wenyuan Road, Nanjing, Jiangsu Province, 210023, China.
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Yan Y, Ye J, Xue XM, Zhu YG. Arsenic Demethylation by a C·As Lyase in Cyanobacterium Nostoc sp. PCC 7120. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:14350-14358. [PMID: 26544154 DOI: 10.1021/acs.est.5b03357] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Arsenic, a ubiquitous toxic substance, exists mainly as inorganic forms in the environment. It is perceived that organoarsenicals can be demethylated and degraded into inorganic arsenic by microorganisms. Few studies have focused on the mechanism of arsenic demethylation in bacteria. Here, we investigated arsenic demethylation in a typical freshwater cyanobacterium Nostoc sp. PCC 7120. This bacterium was able to demethylate monomethylarsenite [MAs(III)] rapidly to arsenite [As(III)] and also had the ability to demethylate monomethylarsenate [MAs(V)] to As(III). The NsarsI encoding a C·As lyase responsible for MAs(III) demethylation was cloned from Nostoc sp. PCC 7120 and heterologously expressed in an As-hypersensitive strain Escherichia coli AW3110 (ΔarsRBC). Expression of NsarsI was shown to confer MAs(III) resistance through arsenic demethylation. The purified NsArsI was further identified and functionally characterized in vitro. NsArsI existed mainly as the trimeric state, and the kinetic data were well-fit to the Hill equation with K0.5 = 7.55 ± 0.33 μM for MAs(III), Vmax = 0.79 ± 0.02 μM min(-1), and h = 2.7. Both of the NsArsI truncated derivatives lacking the C-terminal 10 residues (ArsI10) or 23 residues (ArsI23) had a reduced ability of MAs(III) demethylation. These results provide new insights for understanding the important role of cyanobacteria in arsenic biogeochemical cycling in the environment.
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Affiliation(s)
- Yu Yan
- Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences , Xiamen 361021, People's Republic of China
- University of Chinese Academy of Sciences , Beijing 100049, People's Republic of China
| | - Jun Ye
- Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences , Xiamen 361021, People's Republic of China
| | - Xi-Mei Xue
- Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences , Xiamen 361021, People's Republic of China
| | - Yong-Guan Zhu
- Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences , Xiamen 361021, People's Republic of China
- State Key Lab of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences , Beijing 100085, People's Republic of China
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Jiménez JI, Fraile S, Zafra O, de Lorenzo V. Phenotypic knockouts of selected metabolic pathways by targeting enzymes with camel-derived nanobodies (VHHs). Metab Eng 2015; 30:40-48. [DOI: 10.1016/j.ymben.2015.04.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Revised: 02/16/2015] [Accepted: 04/06/2015] [Indexed: 12/30/2022]
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Barry KP, Ngu A, Cohn EF, Cote JM, Burroughs AM, Gerbino JP, Taylor EA. Exploring allosteric activation of LigAB from Sphingobium sp. strain SYK-6 through kinetics, mutagenesis and computational studies. Arch Biochem Biophys 2015; 567:35-45. [PMID: 25562402 DOI: 10.1016/j.abb.2014.12.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2014] [Revised: 12/19/2014] [Accepted: 12/22/2014] [Indexed: 12/12/2022]
Abstract
The protocatechuate 4,5-dioxygenase (LigAB) from Sphingobium sp. strain SYK-6 is the defining member of the Type II extradiol dioxygenase superfamily (a.k.a. PCA Dioxygenase Superfamily or PCADSF) and plays a key aromatic ring-opening role in the metabolism of several lignin derived aromatic compounds. In our search for alternate substrates and inhibitors of LigAB, we discovered allosteric rate enhancement in the presence of non-substrate protocatechuate-like aldehydes such as vanillin. LigAB has the broadest substrate utilization profile of all protocatechuate (PCA) 4,5-dioxygenase described in the literature, however, the rate enhancement is only observed with PCA, with vanillin increasing kcat for LigAB by 36%. Computational docking has identified a potential site of allosteric binding near the entrance to the active site. Examination of a multiple sequence alignment reveals that many of the residues contributing to this newly identified allosteric pocket are highly conserved within the LigB family of the PCADSF. Point mutants of Phe103α and Ala18β, two residues located in the putative allosteric pocket, display altered rate enhancement as compared to LigAB-WT, providing support for the computationally identified allosteric binding site. Further investigation of this binding site may provide insight into the mechanism of this never before observed allosteric activation in extradiol dioxygenases.
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Affiliation(s)
| | - Abraham Ngu
- Department of Chemistry, Wesleyan University, Middletown, CT 06459, USA
| | - Erin Frances Cohn
- Department of Chemistry, Wesleyan University, Middletown, CT 06459, USA
| | - Joy Marie Cote
- Department of Chemistry, Wesleyan University, Middletown, CT 06459, USA
| | - A Maxwell Burroughs
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA
| | | | - Erika Anne Taylor
- Department of Chemistry, Wesleyan University, Middletown, CT 06459, USA.
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Duarte M, Jauregui R, Vilchez-Vargas R, Junca H, Pieper DH. AromaDeg, a novel database for phylogenomics of aerobic bacterial degradation of aromatics. DATABASE-THE JOURNAL OF BIOLOGICAL DATABASES AND CURATION 2014; 2014:bau118. [PMID: 25468931 PMCID: PMC4250580 DOI: 10.1093/database/bau118] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Understanding prokaryotic transformation of recalcitrant pollutants and the in-situ metabolic nets require the integration of massive amounts of biological data. Decades of biochemical studies together with novel next-generation sequencing data have exponentially increased information on aerobic aromatic degradation pathways. However, the majority of protein sequences in public databases have not been experimentally characterized and homology-based methods are still the most routinely used approach to assign protein function, allowing the propagation of misannotations. AromaDeg is a web-based resource targeting aerobic degradation of aromatics that comprises recently updated (September 2013) and manually curated databases constructed based on a phylogenomic approach. Grounded in phylogenetic analyses of protein sequences of key catabolic protein families and of proteins of documented function, AromaDeg allows query and data mining of novel genomic, metagenomic or metatranscriptomic data sets. Essentially, each query sequence that match a given protein family of AromaDeg is associated to a specific cluster of a given phylogenetic tree and further function annotation and/or substrate specificity may be inferred from the neighboring cluster members with experimentally validated function. This allows a detailed characterization of individual protein superfamilies as well as high-throughput functional classifications. Thus, AromaDeg addresses the deficiencies of homology-based protein function prediction, combining phylogenetic tree construction and integration of experimental data to obtain more accurate annotations of new biological data related to aerobic aromatic biodegradation pathways. We pursue in future the expansion of AromaDeg to other enzyme families involved in aromatic degradation and its regular update. Database URL:http://aromadeg.siona.helmholtz-hzi.de
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Affiliation(s)
- Márcia Duarte
- Microbial Interactions and Processes Research Group, HZI-Helmholtz Centre for Infection Research, Inhoffenstr. 7, D-38124 Braunschweig, Germany, Research Group Microbial Ecology, Metabolism, Genomics and Evolution of Communities of Environmental Microorganisms, CorpoGen. Carrera 5 No. 66A-35, Bogotá, Colombia and Faculty of Basic and Applied Sciences, Universidad Militar Nueva Granada-UMNG, Campus Cajicá, Bogotá DC, Colombia
| | - Ruy Jauregui
- Microbial Interactions and Processes Research Group, HZI-Helmholtz Centre for Infection Research, Inhoffenstr. 7, D-38124 Braunschweig, Germany, Research Group Microbial Ecology, Metabolism, Genomics and Evolution of Communities of Environmental Microorganisms, CorpoGen. Carrera 5 No. 66A-35, Bogotá, Colombia and Faculty of Basic and Applied Sciences, Universidad Militar Nueva Granada-UMNG, Campus Cajicá, Bogotá DC, Colombia Microbial Interactions and Processes Research Group, HZI-Helmholtz Centre for Infection Research, Inhoffenstr. 7, D-38124 Braunschweig, Germany, Research Group Microbial Ecology, Metabolism, Genomics and Evolution of Communities of Environmental Microorganisms, CorpoGen. Carrera 5 No. 66A-35, Bogotá, Colombia and Faculty of Basic and Applied Sciences, Universidad Militar Nueva Granada-UMNG, Campus Cajicá, Bogotá DC, Colombia
| | - Ramiro Vilchez-Vargas
- Microbial Interactions and Processes Research Group, HZI-Helmholtz Centre for Infection Research, Inhoffenstr. 7, D-38124 Braunschweig, Germany, Research Group Microbial Ecology, Metabolism, Genomics and Evolution of Communities of Environmental Microorganisms, CorpoGen. Carrera 5 No. 66A-35, Bogotá, Colombia and Faculty of Basic and Applied Sciences, Universidad Militar Nueva Granada-UMNG, Campus Cajicá, Bogotá DC, Colombia
| | - Howard Junca
- Microbial Interactions and Processes Research Group, HZI-Helmholtz Centre for Infection Research, Inhoffenstr. 7, D-38124 Braunschweig, Germany, Research Group Microbial Ecology, Metabolism, Genomics and Evolution of Communities of Environmental Microorganisms, CorpoGen. Carrera 5 No. 66A-35, Bogotá, Colombia and Faculty of Basic and Applied Sciences, Universidad Militar Nueva Granada-UMNG, Campus Cajicá, Bogotá DC, Colombia Microbial Interactions and Processes Research Group, HZI-Helmholtz Centre for Infection Research, Inhoffenstr. 7, D-38124 Braunschweig, Germany, Research Group Microbial Ecology, Metabolism, Genomics and Evolution of Communities of Environmental Microorganisms, CorpoGen. Carrera 5 No. 66A-35, Bogotá, Colombia and Faculty of Basic and Applied Sciences, Universidad Militar Nueva Granada-UMNG, Campus Cajicá, Bogotá DC, Colombia
| | - Dietmar H Pieper
- Microbial Interactions and Processes Research Group, HZI-Helmholtz Centre for Infection Research, Inhoffenstr. 7, D-38124 Braunschweig, Germany, Research Group Microbial Ecology, Metabolism, Genomics and Evolution of Communities of Environmental Microorganisms, CorpoGen. Carrera 5 No. 66A-35, Bogotá, Colombia and Faculty of Basic and Applied Sciences, Universidad Militar Nueva Granada-UMNG, Campus Cajicá, Bogotá DC, Colombia
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Barry KP, Taylor EA. Characterizing the promiscuity of LigAB, a lignin catabolite degrading extradiol dioxygenase from Sphingomonas paucimobilis SYK-6. Biochemistry 2013; 52:6724-36. [PMID: 23977959 DOI: 10.1021/bi400665t] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
LigAB from Sphingomonas paucimobilis SYK-6 is the only structurally characterized dioxygenase of the largely uncharacterized superfamily of Type II extradiol dioxygenases (EDO). This enzyme catalyzes the oxidative ring-opening of protocatechuate (3,4-dihydroxybenzoic acid or PCA) in a pathway allowing the degradation of lignin derived aromatic compounds (LDACs). LigAB has also been shown to utilize two other LDACs from the same metabolic pathway as substrates, gallate, and 3-O-methyl gallate; however, kcat/KM had not been reported for any of these compounds. In order to assess the catalytic efficiency and get insights into the observed promiscuity of this enzyme, steady-state kinetic analyses were performed for LigAB with these and a library of related compounds. The dioxygenation of PCA by LigAB was highly efficient, with a kcat of 51 s(-1) and a kcat/KM of 4.26 × 10(6) M(-1)s(-1). LigAB demonstrated the ability to use a variety of catecholic molecules as substrates beyond the previously identified gallate and 3-O-methyl gallate, including 3,4-dihydroxybenzamide, homoprotocatechuate, catechol, and 3,4-dihydroxybenzonitrile. Interestingly, 3,4-dihydroxybenzamide (DHBAm) behaves in a manner similar to that of the preferred benzoic acid substrates, with a kcat/Km value only ∼4-fold lower than that for gallate and ∼10-fold higher than that for 3-O-methyl gallate. All of these most active substrates demonstrate mechanistic inactivation of LigAB. Additionally, DHBAm exhibits potent product inhibition that leads to an inactive enzyme, being more highly deactivating at lower substrate concentration, a phenomena that, to our knowledge, has not been reported for another dioxygenase substrate/product pair. These results provide valuable catalytic insight into the reactions catalyzed by LigAB and make it the first Type II EDO that is fully characterized both structurally and kinetically.
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Affiliation(s)
- Kevin P Barry
- Department of Chemistry, Wesleyan University , 52 Lawn Avenue, Middletown, Connecticut 06459, United States
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Luque-Almagro VM, Acera F, Igeño MI, Wibberg D, Roldán MD, Sáez LP, Hennig M, Quesada A, Huertas MJ, Blom J, Merchán F, Escribano MP, Jaenicke S, Estepa J, Guijo MI, Martínez-Luque M, Macías D, Szczepanowski R, Becerra G, Ramirez S, Carmona MI, Gutiérrez O, Manso I, Pühler A, Castillo F, Moreno-Vivián C, Schlüter A, Blasco R. Draft whole genome sequence of the cyanide-degrading bacterium Pseudomonas pseudoalcaligenes CECT5344. Environ Microbiol 2012; 15:253-70. [PMID: 22998548 DOI: 10.1111/j.1462-2920.2012.02875.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2012] [Revised: 08/15/2012] [Accepted: 08/19/2012] [Indexed: 11/30/2022]
Abstract
Pseudomonas pseudoalcaligenes CECT5344 is a Gram-negative bacterium able to tolerate cyanide and to use it as the sole nitrogen source. We report here the first draft of the whole genome sequence of a P. pseudoalcaligenes strain that assimilates cyanide. Three aspects are specially emphasized in this manuscript. First, some generalities of the genome are shown and discussed in the context of other Pseudomonadaceae genomes, including genome size, G + C content, core genome and singletons among other features. Second, the genome is analysed in the context of cyanide metabolism, describing genes probably involved in cyanide assimilation, like those encoding nitrilases, and genes related to cyanide resistance, like the cio genes encoding the cyanide insensitive oxidases. Finally, the presence of genes probably involved in other processes with a great biotechnological potential like production of bioplastics and biodegradation of pollutants also is discussed.
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Affiliation(s)
- Víctor M Luque-Almagro
- Departamento de Bioquímica y Biología Molecular, Universidad de Córdoba, 14071, Córdoba, Spain
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Pérez-Pantoja D, Donoso R, Agulló L, Córdova M, Seeger M, Pieper DH, González B. Genomic analysis of the potential for aromatic compounds biodegradation in Burkholderiales. Environ Microbiol 2011; 14:1091-117. [PMID: 22026719 DOI: 10.1111/j.1462-2920.2011.02613.x] [Citation(s) in RCA: 191] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The relevance of the β-proteobacterial Burkholderiales order in the degradation of a vast array of aromatic compounds, including several priority pollutants, has been largely assumed. In this review, the presence and organization of genes encoding oxygenases involved in aromatics biodegradation in 80 Burkholderiales genomes is analysed. This genomic analysis underscores the impressive catabolic potential of this bacterial lineage, comprising nearly all of the central ring-cleavage pathways reported so far in bacteria and most of the peripheral pathways involved in channelling of a broad diversity of aromatic compounds. The more widespread pathways in Burkholderiales include protocatechuate ortho ring-cleavage, catechol ortho ring-cleavage, homogentisate ring-cleavage and phenylacetyl-CoA ring-cleavage pathways found in at least 60% of genomes analysed. In general, a genus-specific pattern of positional ordering of biodegradative genes is observed in the catabolic clusters of these pathways indicating recent events in its evolutionary history. In addition, a significant bias towards secondary chromosomes, now termed chromids, is observed in the distribution of catabolic genes across multipartite genomes, which is consistent with a genus-specific character. Strains isolated from environmental sources such as soil, rhizosphere, sediment or sludge show a higher content of catabolic genes in their genomes compared with strains isolated from human, animal or plant hosts, but no significant difference is found among Alcaligenaceae, Burkholderiaceae and Comamonadaceae families, indicating that habitat is more of a determinant than phylogenetic origin in shaping aromatic catabolic versatility.
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Affiliation(s)
- Danilo Pérez-Pantoja
- Center for Advanced Studies in Ecology and Biodiversity, Millennium Nucleus in Plant Functional Genomics, Facultad de Ciencias Biológicas, P. Universidad Católica de Chile, Santiago, Chile
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Nogales J, Canales A, Jiménez-Barbero J, Serra B, Pingarrón JM, García JL, Díaz E. Unravelling the gallic acid degradation pathway in bacteria: the gal cluster from Pseudomonas putida. Mol Microbiol 2010; 79:359-74. [PMID: 21219457 DOI: 10.1111/j.1365-2958.2010.07448.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Gallic acid (3,4,5-trihydroxybenzoic acid, GA) is widely distributed in nature, being a major phenolic pollutant and a commonly used antioxidant and building-block for drug development. We have characterized the first complete cluster (gal genes) responsible for growth in GA in a derivative of the model bacterium Pseudomonas putida KT2440. GalT mediates specific GA uptake and chemotaxis, and highlights the critical role of GA transport in bacterial adaptation to GA consumption. The proposed GA degradation via the central intermediate 4-oxalomesaconic acid (OMA) was revisited and all enzymes involved have been identified. Thus, GalD is the prototype of a new subfamily of isomerases that catalyses a biochemical step that remained unknown, i.e. the tautomerization of the OMAketo generated by the GalA dioxygenase to OMAenol. GalB is the founding member of a new family of zinc-containing hydratases that converts OMAenol into 4-carboxy-4-hydroxy-2-oxoadipic acid (CHA). galC encodes the aldolase catalysing CHA cleavage to pyruvic and oxaloacetic acids. The presence of homologous gal clusters outside the Pseudomonas genus sheds light on the evolution and ecology of the gal genes in GA degraders. The gal genes were used for expanding the metabolic abilities of heterologous hosts towards GA degradation, and for engineering a GA cellular biosensor.
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Affiliation(s)
- Juan Nogales
- Department of Environmental Biology, Centro de Investigaciones Biológicas, CSIC. Ramiro de Maeztu 9, 28040 Madrid, Spain
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Vilchez-Vargas R, Junca H, Pieper DH. Metabolic networks, microbial ecology and ‘omics’ technologies: towards understanding in situ biodegradation processes. Environ Microbiol 2010; 12:3089-104. [DOI: 10.1111/j.1462-2920.2010.02340.x] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Abstract
Pseudomonas putida DOT-T1E was used as a model to develop a "phenomics" platform to investigate the ability of P. putida to grow using different carbon, nitrogen, and sulfur sources and in the presence of stress molecules. Results for growth of wild-type DOT-T1E on 90 different carbon sources revealed the existence of a number of previously uncharted catabolic pathways for compounds such as salicylate, quinate, phenylethanol, gallate, and hexanoate, among others. Subsequent screening on the subset of compounds on which wild-type DOT-TIE could grow with four knockout strains in the global regulatory genes Deltacrc, Deltacrp, DeltacyoB, and DeltaptsN allowed analysis of the global response to nutrient supply and stress. The data revealed that most global regulator mutants could grow in a wide variety of substrates, indicating that metabolic fluxes are physiologically balanced. It was found that the Crc mutant did not differ much from the wild-type regarding the use of carbon sources. However, certain pathways are under the preferential control of one global regulator, i.e., metabolism of succinate and d-fructose is influenced by CyoB, and l-arginine is influenced by PtsN. Other pathways can be influenced by more than one global regulator; i.e., l-valine catabolism can be influenced by CyoB and Crp (cyclic AMP receptor protein) while phenylethylamine is affected by Crp, CyoB, and PtsN. These results emphasize the cross talk required in order to ensure proper growth and survival. With respect to N sources, DOT-T1E can use a wide variety of inorganic and organic nitrogen sources. As with the carbon sources, more than one global regulator affected growth with some nitrogen sources; for instance, growth with nucleotides, dipeptides, d-amino acids, and ethanolamine is influenced by Crp, CyoB, and PtsN. A surprising finding was that the Crp mutant was unable to flourish on ammonium. Results for assayed sulfur sources revealed that CyoB controls multiple points in methionine/cysteine catabolism while PtsN and Crc are needed for N-acetyl-l-cysteamine utilization. Growth of global regulator mutants was also influenced by stressors of different types (antibiotics, oxidative agents, and metals). Overall and in combination with results for growth in the presence of various stressors, these phenomics assays provide multifaceted insights into the complex decision-making process involved in nutrient supply, optimization, and survival.
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Abstract
Paenibacillus sp. (formerly Bacillus macerans) strain JJ-1b is able to grow on 4-hydroxybenzoate (4HB) as a sole source of carbon and energy and is known to degrade 4HB via the protocatechuate (PCA) 2,3-cleavage pathway. However, none of the genes involved in this pathway have been identified. In this study, we identified and characterized the JJ-1b genes for the 4HB catabolic pathway via the PCA 2,3-cleavage pathway, which consisted of praR and praABEGFDCHI. Based on the enzyme activities of cell extracts of Escherichia coli carrying praI, praA, praH, praB, praC, and praD, these genes were found to code for 4HB 3-hydroxylase, PCA 2,3-dioxygenase, 5-carboxy-2-hydroxymuconate-6-semialdehyde decarboxylase, 2-hydroxymuconate-6-semialdehyde dehydrogenase, 4-oxalocrotonate (OCA) tautomerase, and OCA decarboxylase, respectively, which are involved in the conversion of 4HB into 2-hydroxypenta-2,4-dienoate (HPD). The praE, praF, and praG gene products exhibited 45 to 61% amino acid sequence identity to the corresponding enzymes responsible for the catabolism of HPD to pyruvate and acetyl coenzyme A. The deduced amino acid sequence of praR showed similarity with those of IclR-type transcriptional regulators. Reverse transcription-PCR analysis revealed that praABEGFDCHI constitute an operon, and these genes were expressed during the growth of JJ-1b on 4HB and PCA. praR-praABEGFDCHI conferred the ability to grow on 4HB to E. coli, suggesting that praEGF were functional for the conversion of HPD to pyruvate and acetyl coenzyme A. A promoter analysis suggested that praR encodes a repressor of the pra operon.
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Brennerova MV, Josefiova J, Brenner V, Pieper DH, Junca H. Metagenomics reveals diversity and abundance of meta-cleavage pathways in microbial communities from soil highly contaminated with jet fuel under air-sparging bioremediation. Environ Microbiol 2009; 11:2216-27. [PMID: 19575758 PMCID: PMC2784041 DOI: 10.1111/j.1462-2920.2009.01943.x] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The extradiol dioxygenase diversity of a site highly contaminated with aliphatic and aromatic hydrocarbons under air-sparging treatment was assessed by functional screening of a fosmid library in Escherichia coli with catechol as substrate. The 235 positive clones from inserts of DNA extracted from contaminated soil were equivalent to one extradiol dioxygenase-encoding gene per 3.6 Mb of DNA screened, indicating a strong selection for genes encoding this function. Three subfamilies were identified as being predominant, with 72, 55 and 43 fosmid inserts carrying genes, related to those encoding TbuE of Ralstonia pickettii PK01 (EXDO-D), IpbC of Pseudomonas sp. JR1 (EXDO-K2) or DbtC of Burkholderia sp. DBT1 (EXDO-Dbt), respectively, whereas genes encoding enzymes related to XylE of Pseudomonas putida mt-2 were not observed. Genes encoding oxygenases related to isopropylbenzene dioxygenases were usually colocalized with genes encoding EXDO-K2 dioxygenases. Functional analysis of representative proteins indicated a subcluster of EXDO-D proteins to show exceptional high affinity towards different catecholic substrates. Based on Vmax/Km specificity constants, a task-sharing between different extradiol dioxygenases in the community of the contaminated site can be supposed, attaining a complementary and community-balanced catalytic power against diverse catecholic derivatives, as necessary for effective degradation of mixtures of aromatics.
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Affiliation(s)
- Maria V Brennerova
- Institute of Microbiology, Czech Academy of Sciences, Prague, Czech Republic.
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Abstract
Ring-cleaving dioxygenases catalyze the oxygenolytic fission of catecholic compounds, a critical step in the aerobic degradation of aromatic compounds by bacteria. Two classes of these enzymes have been identified, based on the mode of ring cleavage: intradiol dioxygenases utilize non-heme Fe(III) to cleave the aromatic nucleus ortho to the hydroxyl substituents; and extradiol dioxygenases utilize non-heme Fe(II) or other divalent metal ions to cleave the aromatic nucleus meta to the hydroxyl substituents. Recent genomic, structural, spectroscopic, and kinetic studies have increased our understanding of the distribution, evolution, and mechanisms of these enzymes. Overall, extradiol dioxygenases appear to be more versatile than their intradiol counterparts. Thus, the former cleave a wider variety of substrates, have evolved on a larger number of structural scaffolds, and occur in a wider variety of pathways, including biosynthetic pathways and pathways that degrade non-aromatic compounds. The catalytic mechanisms of the two enzymes proceed via similar iron-alkylperoxo intermediates. The ability of extradiol enzymes to act on a variety of non-catecholic compounds is consistent with proposed differences in the breakdown of this iron-alkylperoxo intermediate in the two enzymes, involving alkenyl migration in extradiol enzymes and acyl migration in intradiol enzymes. Nevertheless, despite recent advances in our understanding of these fascinating enzymes, the major determinant of the mode of ring cleavage remains unknown.
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Affiliation(s)
- Frédéric H Vaillancourt
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts, USA
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Nogales J, Palsson BØ, Thiele I. A genome-scale metabolic reconstruction of Pseudomonas putida KT2440: iJN746 as a cell factory. BMC SYSTEMS BIOLOGY 2008; 2:79. [PMID: 18793442 PMCID: PMC2569920 DOI: 10.1186/1752-0509-2-79] [Citation(s) in RCA: 166] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/05/2008] [Accepted: 09/16/2008] [Indexed: 11/16/2022]
Abstract
Background Pseudomonas putida is the best studied pollutant degradative bacteria and is harnessed by industrial biotechnology to synthesize fine chemicals. Since the publication of P. putida KT2440's genome, some in silico analyses of its metabolic and biotechnology capacities have been published. However, global understanding of the capabilities of P. putida KT2440 requires the construction of a metabolic model that enables the integration of classical experimental data along with genomic and high-throughput data. The constraint-based reconstruction and analysis (COBRA) approach has been successfully used to build and analyze in silico genome-scale metabolic reconstructions. Results We present a genome-scale reconstruction of P. putida KT2440's metabolism, iJN746, which was constructed based on genomic, biochemical, and physiological information. This manually-curated reconstruction accounts for 746 genes, 950 reactions, and 911 metabolites. iJN746 captures biotechnologically relevant pathways, including polyhydroxyalkanoate synthesis and catabolic pathways of aromatic compounds (e.g., toluene, benzoate, phenylacetate, nicotinate), not described in other metabolic reconstructions or biochemical databases. The predictive potential of iJN746 was validated using experimental data including growth performance and gene deletion studies. Furthermore, in silico growth on toluene was found to be oxygen-limited, suggesting the existence of oxygen-efficient pathways not yet annotated in P. putida's genome. Moreover, we evaluated the production efficiency of polyhydroxyalkanoates from various carbon sources and found fatty acids as the most prominent candidates, as expected. Conclusion Here we presented the first genome-scale reconstruction of P. putida, a biotechnologically interesting all-surrounder. Taken together, this work illustrates the utility of iJN746 as i) a knowledge-base, ii) a discovery tool, and iii) an engineering platform to explore P. putida's potential in bioremediation and bioplastic production.
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Affiliation(s)
- Juan Nogales
- Departamento de Microbiología Molecular, Centro de Investigaciones Biológicas-CSIC, Ramiro de Maeztu 9, Madrid, 28040, Spain.
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Deciphering the genetic determinants for aerobic nicotinic acid degradation: the nic cluster from Pseudomonas putida KT2440. Proc Natl Acad Sci U S A 2008; 105:11329-34. [PMID: 18678916 DOI: 10.1073/pnas.0802273105] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The aerobic catabolism of nicotinic acid (NA) is considered a model system for degradation of N-heterocyclic aromatic compounds, some of which are major environmental pollutants; however, the complete set of genes as well as the structural-functional relationships of most of the enzymes involved in this process are still unknown. We have characterized a gene cluster (nic genes) from Pseudomonas putida KT2440 responsible for the aerobic NA degradation in this bacterium and when expressed in heterologous hosts. The biochemistry of the NA degradation through the formation of 2,5-dihydroxypyridine and maleamic acid has been revisited, and some gene products become the prototype of new types of enzymes with unprecedented molecular architectures. Thus, the initial hydroxylation of NA is catalyzed by a two-component hydroxylase (NicAB) that constitutes the first member of the xanthine dehydrogenase family whose electron transport chain to molecular oxygen includes a cytochrome c domain. The Fe(2+)-dependent dioxygenase (NicX) converts 2,5-dihydroxypyridine into N-formylmaleamic acid, and it becomes the founding member of a new family of extradiol ring-cleavage dioxygenases. Further conversion of N-formylmaleamic acid to formic and maleamic acid is catalyzed by the NicD protein, the only deformylase described so far whose catalytic triad is similar to that of some members of the alpha/beta-hydrolase fold superfamily. This work allows exploration of the existence of orthologous gene clusters in saprophytic bacteria and some pathogens, where they might stimulate studies on their role in virulence, and it provides a framework to develop new biotechnological processes for detoxification/biotransformation of N-heterocyclic aromatic compounds.
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Li X, Guo M, Fan J, Tang W, Wang D, Ge H, Rong H, Teng M, Niu L, Liu Q, Hao Q. Crystal structure of 3-hydroxyanthranilic acid 3,4-dioxygenase from Saccharomyces cerevisiae: a special subgroup of the type III extradiol dioxygenases. Protein Sci 2006; 15:761-73. [PMID: 16522801 PMCID: PMC2242480 DOI: 10.1110/ps.051967906] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
3-Hydroxyanthranilic acid 3,4-dioxygenase (3HAO) is a non-heme ferrous extradiol dioxygenase in the kynurenine pathway from tryptophan. It catalyzes the conversion of 3-hydroxyanthranilate (HAA) to quinolinic acid (QUIN), an endogenous neurotoxin, via the activation of N-methyl-D-aspartate (NMDA) receptors and the precursor of NAD(+) biosynthesis. The crystal structure of 3HAO from S. cerevisiae at 2.4 A resolution shows it to be a member of the functionally diverse cupin superfamily. The structure represents the first eukaryotic 3HAO to be resolved. The enzyme forms homodimers, with two nickel binding sites per molecule. One of the bound nickel atoms occupies the proposed ferrous-coordinated active site, which is located in a conserved double-strand beta-helix domain. Examination of the structure reveals the participation of a series of residues in catalysis different from other extradiol dioxygenases. Together with two iron-binding residues (His49 and Glu55), Asp120, Asn51, Glu111, and Arg114 form a hydrogen-bonding network; this hydrogen-bond network is key to the catalysis of 3HAO. Residues Arg101, Gln59, and the substrate-binding hydrophobic pocket are crucial for substrate specificity. Structure comparison with 3HAO from Ralstonia metallidurans reveals similarities at the active site and suggests the same catalytic mechanism in prokaryotic and eukaryotic 3HAO. Based on sequence comparison, we suggest that bicupin of human 3HAO is the first example of evolution from a monocupin dimer to bicupin monomer in the diverse cupin superfamilies. Based on the model of the substrate HAA at the active site of Y3HAO, we propose a mechanism of catalysis for 3HAO.
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Affiliation(s)
- Xiaowu Li
- Hefei National Laboratory for Physical Sciences at Microsale and School of Life Sciences, University of Science & Technology of China, Hefei, Anhui 230027, China
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