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He K, Li W, Tang L, Li W, Lv S, Xing D. Suppressing Methane Production to Boost High-Purity Hydrogen Production in Microbial Electrolysis Cells. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:11931-11951. [PMID: 35969804 DOI: 10.1021/acs.est.2c02371] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Hydrogen gas (H2) is an attractive fuel carrier due to its high specific enthalpy; moreover, it is a clean source of energy because in the combustion reaction with oxygen (O2) it produces water as the only byproduct. The microbial electrolysis cell (MEC) is a promising technology for producing H2 from simple or complex organics present in wastewater and solid wastes. Methanogens and non-archaeal methane (CH4)-producing microorganisms (NAMPMs) often grow in the MECs and lead to rapid conversion of produced H2 to CH4. Moreover, non-archaeal methane production (NAMP) catalyzed by nitrogenase of photosynthetic bacteria was always overlooked. Thus, suppression of CH4 production is required to enhance H2 yield and production rate. This review comprehensively addresses the principles and current state-of-the-art technologies for suppressing methanogenesis and NAMP in MECs. Noteworthy, specific strategies aimed at the inhibition of methanogenic enzymes and nitrogenase could be a more direct approach than physical and chemical strategies for repressing the growth of methanogenic archaea. In-depth studies on the multiomics of CH4 metabolism can possibly provide insights into sustainable and efficient approaches for suppressing metabolic pathways of methanogenesis and NAMP. The main objective of this review is to highlight key concepts, directions, and challenges related to boosting H2 generation by suppressing CH4 production in MECs. Finally, perspectives are briefly outlined to guide and advance the future direction of MECs for production of high-purity H2 based on genetic and metabolic engineering and on the interspecific interactions.
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Affiliation(s)
- Kuanchang He
- Research Center for Eco-environmental Engineering, Dongguan University of Technology, Dongguan 523808, China
| | - Wei Li
- Research Center for Eco-environmental Engineering, Dongguan University of Technology, Dongguan 523808, China
| | - Longxiang Tang
- Research Center for Eco-environmental Engineering, Dongguan University of Technology, Dongguan 523808, China
| | - Wei Li
- Research Center for Eco-environmental Engineering, Dongguan University of Technology, Dongguan 523808, China
| | - Sihao Lv
- Research Center for Eco-environmental Engineering, Dongguan University of Technology, Dongguan 523808, China
| | - Defeng Xing
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
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2
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Wang P, Li X, Chu S, Su Y, Wu D, Xie B. Metatranscriptomic insight into the effects of antibiotic exposure on performance during anaerobic co-digestion of food waste and sludge. JOURNAL OF HAZARDOUS MATERIALS 2022; 423:127163. [PMID: 34530275 DOI: 10.1016/j.jhazmat.2021.127163] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Revised: 08/31/2021] [Accepted: 09/04/2021] [Indexed: 06/13/2023]
Abstract
Antibiotics are inevitably entered into anaerobic co-digestion (AcoD) system of food waste (FW) and sludge along with the addition of abundant antibiotic-containing activated sludge. However, the in-depth insights into antibiotics affecting AcoD performance have not comprehensively studied. In present study, the results showed that tetracycline (TC), sulfamethoxazole (SMZ) and erythromycin (ERY) inhibited and delayed methane production except for 5 mg/L ERY. By comparison, TC and SMZ significantly inhibited the cumulative methane yields (one-way ANOVA, p < 0.01), and the inhibition effects were magnified as the antibiotic level increased. Physicochemical and methane yield analysis indicated antibiotics inhibited hydrolysis process and delayed methanogenesis process, which was in line with the declined abundance of acetogenic Proteiniphilum and hydrogenotrophic Methanobacterium during AcoD. Furthermore, metatranscriptomic analysis demonstrated the microbial activities of major organic and energy metabolism were down-regulated under antibiotics exposure, thereby down-regulating the expressions of key coenzymes (coenzymes M, F420, methanofuran) biosynthesis for methanogenesis and methane metabolism. The declined methanogenesis activity was completely consistent with the inhibited activity of dominant Methanosarcina and methane production, proving the importance of Methanosarcina on methane production. This study provides new metatranscriptomic evidence into the effects of antibiotics on methanogenesis during AcoD.
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Affiliation(s)
- Panliang Wang
- Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, PR China; Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, PR China
| | - Xunan Li
- Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, PR China; Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, PR China
| | - Siqin Chu
- Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, PR China; Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, PR China
| | - Yinglong Su
- Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, PR China; Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, PR China
| | - Dong Wu
- Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, PR China; Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, PR China
| | - Bing Xie
- Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, PR China; Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, PR China; Engineering Research Center for Nanophotonics and Advanced Instrument, Ministry of Education, East China Normal University, Shanghai 200062, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China.
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Hemmann JL, Brühwiler MR, Bortfeld-Miller M, Vorholt JA. Structural diversity of the coenzyme methylofuran and identification of enzymes for the biosynthesis of its polyglutamate side chain. J Biol Chem 2021; 296:100682. [PMID: 33894199 PMCID: PMC8141765 DOI: 10.1016/j.jbc.2021.100682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 04/07/2021] [Accepted: 04/18/2021] [Indexed: 11/17/2022] Open
Abstract
Methylofuran (MYFR) is a formyl-carrying coenzyme essential for the oxidation of formaldehyde in most methylotrophic bacteria. In Methylorubrum extorquens, MYFR contains a large and branched polyglutamate side chain of up to 24 glutamates. These glutamates play an essential role in interfacing the coenzyme with the formyltransferase/hydrolase complex, an enzyme that generates formate. To date, MYFR has not been identified in other methylotrophs, and it is unknown whether its structural features are conserved. Here, we examined nine bacterial strains for the presence and structure of MYFR using high-resolution liquid chromatography-mass spectrometry (LC-MS). Two of the strains produced MYFR as present in M. extorquens, while a modified MYFR containing tyramine instead of tyrosine in its core structure was detected in six strains. When M. extorquens was grown in the presence of tyramine, the compound was readily incorporated into MYFR, indicating that the biosynthetic enzymes are unable to discriminate tyrosine from tyramine. Using gene deletions in combination with LC-MS analyses, we identified three genes, orf5, orfY, and orf17 that are essential for MYFR biosynthesis. Notably, the orfY and orf5 mutants accumulated short MYFR intermediates with only one and two glutamates, respectively, suggesting that these enzymes catalyze glutamate addition. Upon homologous overexpression of orf5, a drastic increase in the number of glutamates in MYFR was observed (up to 40 glutamates), further corroborating the function of Orf5 as a glutamate ligase. We thus renamed OrfY and Orf5 to MyfA and MyfB to highlight that these enzymes are specifically involved in MYFR biosynthesis.
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Pan X, Yu J, Du Q, Zeng S, Liu J, Jiao Q, Zhang H. Efficient synthesis of γ-glutamyl compounds by co-expression of γ-glutamylmethylamide synthetase and polyphosphate kinase in engineered Escherichia coli. J Ind Microbiol Biotechnol 2020; 47:573-583. [PMID: 32885332 DOI: 10.1007/s10295-020-02305-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Accepted: 08/25/2020] [Indexed: 12/22/2022]
Abstract
γ-Glutamyl compounds have unveiled their importance as active substances or precursors of pharmaceuticals. In this research, an approach for enzymatic synthesis of γ-glutamyl compounds was developed using γ-glutamylmethylamide synthetase (GMAS) from Methylovorus mays and polyphosphate kinase (PPK) from Corynebacterium glutamicum. GMAS and PPK were co-recombined in pETDuet-1 plasmid and co-expressed in E. coli BL21 (DE3), and the enzymatic properties of GMAS and PPK were investigated, respectively. Under the catalysis of the co-expression system, L-theanine was synthesized with 89.8% conversion when the substrate molar ratio of sodium glutamate and ethylamine (1:1.4) and only 2 mM ATP were used. A total of 14 γ-glutamyl compounds were synthesized by this one-pot method and purified by cation exchange resin and isoelectric point crystallization with a yield range from 22.3 to 72.7%. This study provided an efficient approach for the synthesis of γ-glutamyl compounds by GMAS and PPK co-expression system.
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Affiliation(s)
- Xinru Pan
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, 210023, Jiangsu, China
| | - Jinhai Yu
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, 210023, Jiangsu, China
| | - Qinglin Du
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, 210023, Jiangsu, China
| | - Shuiyun Zeng
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, 210023, Jiangsu, China
| | - Junzhong Liu
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, 210023, Jiangsu, China.
| | - Qingcai Jiao
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, 210023, Jiangsu, China.
| | - Hongjuan Zhang
- School of Pharmacy, Nanjing Medical University, Nanjing, 210029, Jiangsu, China.
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Genome-Scale Metabolic Modeling of Archaea Lends Insight into Diversity of Metabolic Function. ARCHAEA-AN INTERNATIONAL MICROBIOLOGICAL JOURNAL 2017; 2017:9763848. [PMID: 28133437 PMCID: PMC5241448 DOI: 10.1155/2017/9763848] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Revised: 10/17/2016] [Accepted: 11/01/2016] [Indexed: 02/07/2023]
Abstract
Decades of biochemical, bioinformatic, and sequencing data are currently being systematically compiled into genome-scale metabolic reconstructions (GEMs). Such reconstructions are knowledge-bases useful for engineering, modeling, and comparative analysis. Here we review the fifteen GEMs of archaeal species that have been constructed to date. They represent primarily members of the Euryarchaeota with three-quarters comprising representative of methanogens. Unlike other reviews on GEMs, we specially focus on archaea. We briefly review the GEM construction process and the genealogy of the archaeal models. The major insights gained during the construction of these models are then reviewed with specific focus on novel metabolic pathway predictions and growth characteristics. Metabolic pathway usage is discussed in the context of the composition of each organism's biomass and their specific energy and growth requirements. We show how the metabolic models can be used to study the evolution of metabolism in archaea. Conservation of particular metabolic pathways can be studied by comparing reactions using the genes associated with their enzymes. This demonstrates the utility of GEMs to evolutionary studies, far beyond their original purpose of metabolic modeling; however, much needs to be done before archaeal models are as extensively complete as those for bacteria.
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Peterson JR, Thor S, Kohler L, Kohler PR, Metcalf WW, Luthey-Schulten Z. Genome-wide gene expression and RNA half-life measurements allow predictions of regulation and metabolic behavior in Methanosarcina acetivorans. BMC Genomics 2016; 17:924. [PMID: 27852217 PMCID: PMC5112694 DOI: 10.1186/s12864-016-3219-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 10/26/2016] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND While a few studies on the variations in mRNA expression and half-lives measured under different growth conditions have been used to predict patterns of regulation in bacterial organisms, the extent to which this information can also play a role in defining metabolic phenotypes has yet to be examined systematically. Here we present the first comprehensive study for a model methanogen. RESULTS We use expression and half-life data for the methanogen Methanosarcina acetivorans growing on fast- and slow-growth substrates to examine the regulation of its genes. Unlike Escherichia coli where only small shifts in half-lives were observed, we found that most mRNA have significantly longer half-lives for slow growth on acetate compared to fast growth on methanol or trimethylamine. Interestingly, half-life shifts are not uniform across functional classes of enzymes, suggesting the existence of a selective stabilization mechanism for mRNAs. Using the transcriptomics data we determined whether transcription or degradation rate controls the change in transcript abundance. Degradation was found to control abundance for about half of the metabolic genes underscoring its role in regulating metabolism. Genes involved in half of the metabolic reactions were found to be differentially expressed among the substrates suggesting the existence of drastically different metabolic phenotypes that extend beyond just the methanogenesis pathways. By integrating expression data with an updated metabolic model of the organism (iST807) significant differences in pathway flux and production of metabolites were predicted for the three growth substrates. CONCLUSIONS This study provides the first global picture of differential expression and half-lives for a class II methanogen, as well as provides the first evidence in a single organism that drastic genome-wide shifts in RNA half-lives can be modulated by growth substrate. We determined which genes in each metabolic pathway control the flux and classified them as regulated by transcription (e.g. transcription factor) or degradation (e.g. post-transcriptional modification). We found that more than half of genes in metabolism were controlled by degradation. Our results suggest that M. acetivorans employs extensive post-transcriptional regulation to optimize key metabolic steps, and more generally that degradation could play a much greater role in optimizing an organism's metabolism than previously thought.
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Affiliation(s)
- Joseph R. Peterson
- Department of Chemistry, University of Illinois at Urbana-Champaign, 505 S Mathews Ave, Urbana, 60801 IL USA
| | - ShengShee Thor
- Center for Biophysics and Computational Biology, University of Illinois at Urbana-Champaign, 1110 W Green St, Urbana, 60801 IL USA
| | - Lars Kohler
- Department of Chemistry, University of Illinois at Urbana-Champaign, 505 S Mathews Ave, Urbana, 60801 IL USA
| | - Petra R.A. Kohler
- Department of Microbiology, University of Illinois at Urbana-Champaign, 601 S Goodwin AveIL, Urbana, 60801 USA
| | - William W. Metcalf
- Department of Microbiology, University of Illinois at Urbana-Champaign, 601 S Goodwin AveIL, Urbana, 60801 USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, 1206 W Gregory DrIL, Urbana, 60801 USA
| | - Zaida Luthey-Schulten
- Department of Chemistry, University of Illinois at Urbana-Champaign, 505 S Mathews Ave, Urbana, 60801 IL USA
- Center for Biophysics and Computational Biology, University of Illinois at Urbana-Champaign, 1110 W Green St, Urbana, 60801 IL USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, 1206 W Gregory DrIL, Urbana, 60801 USA
- Beckman Institute, University of Illinois at Urbana-Champaign, 405 N Mathews Ave, Urbana, 60801 IL USA
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7
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Chistoserdova L. Wide Distribution of Genes for Tetrahydromethanopterin/Methanofuran-Linked C1 Transfer Reactions Argues for Their Presence in the Common Ancestor of Bacteria and Archaea. Front Microbiol 2016; 7:1425. [PMID: 27679616 PMCID: PMC5020050 DOI: 10.3389/fmicb.2016.01425] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2016] [Accepted: 08/29/2016] [Indexed: 12/14/2022] Open
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Abstract
Amides are widespread in biologically active compounds with a broad range of applications in biotechnology, agriculture and medicine. Therefore, as alternative to chemical synthesis the biocatalytic amide synthesis is a very interesting field of research. As usual, Nature can serve as guide in the quest for novel biocatalysts. Several mechanisms for carboxylate activation involving mainly acyl-adenylate, acyl-phosphate or acyl-enzyme intermediates have been discovered, but also completely different pathways to amides are found. In addition to ribosomes, selected enzymes of almost all main enzyme classes are able to synthesize amides. In this review we give an overview about amide synthesis in Nature, as well as biotechnological applications of these enzymes. Moreover, several examples of biocatalytic amide synthesis are given.
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Hemmann JL, Saurel O, Ochsner AM, Stodden BK, Kiefer P, Milon A, Vorholt JA. The One-carbon Carrier Methylofuran from Methylobacterium extorquens AM1 Contains a Large Number of α- and γ-Linked Glutamic Acid Residues. J Biol Chem 2016; 291:9042-51. [PMID: 26895963 DOI: 10.1074/jbc.m116.714741] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Indexed: 11/06/2022] Open
Abstract
Methylobacterium extorquens AM1 uses dedicated cofactors for one-carbon unit conversion. Based on the sequence identities of enzymes and activity determinations, a methanofuran analog was proposed to be involved in formaldehyde oxidation in Alphaproteobacteria. Here, we report the structure of the cofactor, which we termed methylofuran. Using an in vitro enzyme assay and LC-MS, methylofuran was identified in cell extracts and further purified. From the exact mass and MS-MS fragmentation pattern, the structure of the cofactor was determined to consist of a polyglutamic acid side chain linked to a core structure similar to the one present in archaeal methanofuran variants. NMR analyses showed that the core structure contains a furan ring. However, instead of the tyramine moiety that is present in methanofuran cofactors, a tyrosine residue is present in methylofuran, which was further confirmed by MS through the incorporation of a (13)C-labeled precursor. Methylofuran was present as a mixture of different species with varying numbers of glutamic acid residues in the side chain ranging from 12 to 24. Notably, the glutamic acid residues were not solely γ-linked, as is the case for all known methanofurans, but were identified by NMR as a mixture of α- and γ-linked amino acids. Considering the unusual peptide chain, the elucidation of the structure presented here sets the basis for further research on this cofactor, which is probably the largest cofactor known so far.
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Affiliation(s)
- Jethro L Hemmann
- From the Institute of Microbiology, ETH Zurich, Vladimir-Prelog-Weg 4, 8093 Zurich, Switzerland
| | - Olivier Saurel
- Institute of Pharmacology and Structural Biology, CNRS and Université de Toulouse-Paul Sabatier, 31077 Toulouse, France, and
| | - Andrea M Ochsner
- From the Institute of Microbiology, ETH Zurich, Vladimir-Prelog-Weg 4, 8093 Zurich, Switzerland
| | - Barbara K Stodden
- Laboratoire des Interactions Plantes Microorganismes, INRA/CNRS 441-2594, Castanet Tolosan, France
| | - Patrick Kiefer
- From the Institute of Microbiology, ETH Zurich, Vladimir-Prelog-Weg 4, 8093 Zurich, Switzerland
| | - Alain Milon
- Institute of Pharmacology and Structural Biology, CNRS and Université de Toulouse-Paul Sabatier, 31077 Toulouse, France, and
| | - Julia A Vorholt
- From the Institute of Microbiology, ETH Zurich, Vladimir-Prelog-Weg 4, 8093 Zurich, Switzerland,
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10
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Walker MC, van der Donk WA. The many roles of glutamate in metabolism. J Ind Microbiol Biotechnol 2015; 43:419-30. [PMID: 26323613 DOI: 10.1007/s10295-015-1665-y] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2015] [Accepted: 07/25/2015] [Indexed: 12/20/2022]
Abstract
The amino acid glutamate is a major metabolic hub in many organisms and as such is involved in diverse processes in addition to its role in protein synthesis. Nitrogen assimilation, nucleotide, amino acid, and cofactor biosynthesis, as well as secondary natural product formation all utilize glutamate in some manner. Glutamate also plays a role in the catabolism of certain amines. Understanding glutamate's role in these various processes can aid in genome mining for novel metabolic pathways or the engineering of pathways for bioremediation or chemical production of valuable compounds.
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Affiliation(s)
- Mark C Walker
- Department of Chemistry and Howard Hughes Medical Institute, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL, 61801, USA
| | - Wilfred A van der Donk
- Department of Chemistry and Howard Hughes Medical Institute, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL, 61801, USA.
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Identification of the Final Two Genes Functioning in Methanofuran Biosynthesis in Methanocaldococcus jannaschii. J Bacteriol 2015; 197:2850-8. [PMID: 26100040 DOI: 10.1128/jb.00401-15] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Accepted: 06/15/2015] [Indexed: 12/31/2022] Open
Abstract
UNLABELLED All methanofuran structural variants contain a basic core structure of 4-[N-(γ-l-glutamyl)-p-(β-aminoethyl)phenoxymethyl]-(aminomethyl)furan (APMF-Glu) but have different side chains depending on the source organism. Recently, we identified four genes (MfnA, MfnB, MfnC, and MfnD) that are responsible for the biosynthesis of the methanofuran precursor γ-glutamyltyramine and 5-(aminomethyl)-3-furanmethanol-phosphate (F1-P) from tyrosine, glutamate, glyceraldehyde-3-P, and alanine in Methanocaldococcus jannaschii. How γ-glutamyltyramine and F1-P couple together to form the core structure of methanofuran was previously unknown. Here, we report the identification of two enzymes encoded by the genes mj0458 and mj0840 that catalyze the formation of F1-PP from ATP and F1-P and the condensation of F1-PP with γ-glutamyltyramine, respectively, to form APMF-Glu. We have annotated these enzymes as MfnE and MfnF, respectively, representing the fifth and sixth enzymes in the methanofuran biosynthetic pathway to be identified. Although MfnE was previously reported as an archaeal adenylate kinase, our present results show that MfnE is a promiscuous enzyme and that its possible physiological role is to produce F1-PP. Unlike other enzymes catalyzing coupling reactions involving pyrophosphate as the leaving group, MfnF exhibits a distinctive α/β two-layer sandwich structure. By comparing MfnF with thiamine synthase and dihydropteroate synthase, a substitution nucleophilic unimolecular (SN-1) reaction mechanism is proposed for MfnF. With the identification of MfnE and MfnF, the biosynthetic pathway for the methanofuran core structure APMF-Glu is complete. IMPORTANCE This work describes the identification of the final two enzymes responsible for catalyzing the biosynthesis of the core structure of methanofuran. The gene products of mj0458 and mj0840 catalyze the formation of F1-PP and the coupling of F1-PP with γ-glutamyltyramine, respectively, to form APMF-Glu. Although the chemistry of such a coupling reaction is widespread in biochemistry, we provide here the first evidence that such a mechanism is used in methanofuran biosynthesis. MfnF belongs to the hydantoinase A family (PF01968) and exhibits a unique α/β two-layer sandwich structure that is different from the enzymes catalyzing similar reactions. Our results show that MfnF catalyzes the formation of an ether bond during methanofuran biosynthesis. Therefore, this work further expands the functionality of this enzyme family.
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12
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Wang Y, Jones MK, Xu H, Ray WK, White RH. Mechanism of the Enzymatic Synthesis of 4-(Hydroxymethyl)-2-furancarboxaldehyde-phosphate (4-HFC-P) from Glyceraldehyde-3-phosphate Catalyzed by 4-HFC-P Synthase. Biochemistry 2015; 54:2997-3008. [DOI: 10.1021/acs.biochem.5b00176] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yu Wang
- Department of Biochemistry, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, United States
| | - Michael K. Jones
- Department of Biochemistry, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, United States
| | - Huimin Xu
- Department of Biochemistry, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, United States
| | - W. Keith Ray
- Department of Biochemistry, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, United States
| | - Robert H. White
- Department of Biochemistry, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, United States
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13
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Goswami A, Van Lanen SG. Enzymatic strategies and biocatalysts for amide bond formation: tricks of the trade outside of the ribosome. MOLECULAR BIOSYSTEMS 2015; 11:338-53. [PMID: 25418915 PMCID: PMC4304603 DOI: 10.1039/c4mb00627e] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Amide bond-containing (ABC) biomolecules are some of the most intriguing and functionally significant natural products with unmatched utility in medicine, agriculture and biotechnology. The enzymatic formation of an amide bond is therefore a particularly interesting platform for engineering the synthesis of structurally diverse natural and unnatural ABC molecules for applications in drug discovery and molecular design. As such, efforts to unravel the mechanisms involved in carboxylate activation and substrate selection has led to the characterization of a number of structurally and functionally distinct protein families involved in amide bond synthesis. Unlike ribosomal synthesis and thio-templated synthesis using nonribosomal peptide synthetases, which couple the hydrolysis of phosphoanhydride bond(s) of ATP and proceed via an acyl-adenylate intermediate, here we discuss two mechanistically alternative strategies: ATP-dependent enzymes that generate acylphosphate intermediates and ATP-independent transacylation strategies. Several examples highlighting the function and synthetic utility of these amide bond-forming strategies are provided.
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Affiliation(s)
- Anwesha Goswami
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 S. Limestone, Lexington, KY 40536, USA.
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14
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Allen KD, White RH. Identification of structurally diverse methanofuran coenzymes in methanococcales that are both N-formylated and N-acetylated. Biochemistry 2014; 53:6199-210. [PMID: 25203397 DOI: 10.1021/bi500973h] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Methanofuran (MF) is a coenzyme necessary for the first step of methanogenesis from CO2. The well-characterized MF core structure is 4-[N-(γ-l-glutamyl-γ-l-glutamyl)-p-(β-aminoethyl)phenoxymethyl]-2-(aminomethyl)furan (APMF-γ-Glu2). Three different MF structures that differ on the basis of the composition of their side chains have been determined previously. Here, we use liquid chromatography coupled with high-resolution mass spectrometry and a variety of biochemical methods to deduce the unique structures of MFs present in four different methanogens in the order Methanococcales. This is the first detailed characterization of the MF occurring in methanogens of this order. MF in each of these organisms contains the expected APMF-γ-Glu2; however, the composition of the side chain is different from that of the previously described MF structures. In Methanocaldococcus jannaschii, additional γ-linked glutamates that range from 7 to 12 residues are present. The MF coenzymes in Methanococcus maripaludis, Methanococcus vannielii, and Methanothermococcus okinawensis also have additional glutamate residues but interestingly also contain a completely different chemical moiety in the middle of the side chain that we have identified as N-(3-carboxy-2- or 3-hydroxy-1-oxopropyl)-l-aspartic acid. This addition results in the terminal γ-linked glutamates being incorporated in the opposite orientation. In addition to these nonacylated MF coenzymes, we also identified the corresponding N-formyl-MF and, surprisingly, N-acetyl-MF derivatives. N-Acetyl-MF has never been observed or implied to be functioning in nature and may represent a new route for acetate formation in methanogens.
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Affiliation(s)
- Kylie D Allen
- Department of Biochemistry, Virginia Polytechnic Institute and State University , Blacksburg, Virginia 24061-0308, United States
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