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Li J, Mui JWY, da Silva BM, Pires DEV, Ascher DB, Madiedo Soler N, Goddard-Borger ED, Williams SJ. A Broad-Spectrum α-Glucosidase of Glycoside Hydrolase Family 13 from Marinovum sp., a Member of the Roseobacter Clade. Appl Biochem Biotechnol 2024:10.1007/s12010-023-04820-3. [PMID: 38180643 DOI: 10.1007/s12010-023-04820-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/19/2023] [Indexed: 01/06/2024]
Abstract
Glycoside hydrolases (GHs) are a diverse group of enzymes that catalyze the hydrolysis of glycosidic bonds. The Carbohydrate-Active enZymes (CAZy) classification organizes GHs into families based on sequence data and function, with fewer than 1% of the predicted proteins characterized biochemically. Consideration of genomic context can provide clues to infer possible enzyme activities for proteins of unknown function. We used the MultiGeneBLAST tool to discover a gene cluster in Marinovum sp., a member of the marine Roseobacter clade, that encodes homologues of enzymes belonging to the sulfoquinovose monooxygenase pathway for sulfosugar catabolism. This cluster lacks a gene encoding a classical family GH31 sulfoquinovosidase candidate, but which instead includes an uncharacterized family GH13 protein (MsGH13) that we hypothesized could be a non-classical sulfoquinovosidase. Surprisingly, recombinant MsGH13 lacks sulfoquinovosidase activity and is a broad-spectrum α-glucosidase that is active on a diverse array of α-linked disaccharides, including maltose, sucrose, nigerose, trehalose, isomaltose, and kojibiose. Using AlphaFold, a 3D model for the MsGH13 enzyme was constructed that predicted its active site shared close similarity with an α-glucosidase from Halomonas sp. H11 of the same GH13 subfamily that shows narrower substrate specificity.
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Affiliation(s)
- Jinling Li
- School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Victoria, 3010, Australia
| | - Janice W-Y Mui
- School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Victoria, 3010, Australia
| | - Bruna M da Silva
- Computational Biology and Clinical Informatics, Baker Heart and Diabetes Institute, Melbourne, Victoria, 3004, Australia
- School of Computing and Information Systems, University of Melbourne, Parkville, Victoria, 3010, Australia
| | - Douglas E V Pires
- Computational Biology and Clinical Informatics, Baker Heart and Diabetes Institute, Melbourne, Victoria, 3004, Australia
- School of Computing and Information Systems, University of Melbourne, Parkville, Victoria, 3010, Australia
- School of Chemistry and Molecular Biosciences, University of Queensland, St Lucia, Queensland, 4072, Australia
| | - David B Ascher
- Computational Biology and Clinical Informatics, Baker Heart and Diabetes Institute, Melbourne, Victoria, 3004, Australia
- School of Chemistry and Molecular Biosciences, University of Queensland, St Lucia, Queensland, 4072, Australia
| | - Niccolay Madiedo Soler
- ACRF Chemical Biology Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, 3052, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria, 3052, Australia
| | - Ethan D Goddard-Borger
- ACRF Chemical Biology Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, 3052, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria, 3052, Australia
| | - Spencer J Williams
- School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Victoria, 3010, Australia.
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2
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Yan C, Han W, Zhou Q, Niwa K, Tang MJ, Burch JE, Zhang Y, Delgadillo DA, Sun Z, Wu Z, Jacobsen SE, Nelson H, Houk KN, Tang Y. Genome Mining from Agriculturally Relevant Fungi Led to a d-Glucose Esterified Polyketide with a Terpene-like Core Structure. J Am Chem Soc 2023; 145:25080-25085. [PMID: 37948671 PMCID: PMC10682982 DOI: 10.1021/jacs.3c10179] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 11/06/2023] [Accepted: 11/07/2023] [Indexed: 11/12/2023]
Abstract
Comparison of biosynthetic gene clusters (BGCs) found in devastating plant pathogens and biocontrol fungi revealed an uncharacterized and conserved polyketide BGC. Genome mining identified the associated metabolite to be treconorin, which has a terpene-like, trans-fused 5,7-bicyclic core that is proposed to derive from a (4 + 3) cycloaddition. The core is esterified with d-glucose, which derives from the glycosidic cleavage of a trehalose ester precursor. This glycomodification strategy is different from the commonly observed glycosylation of natural products.
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Affiliation(s)
- Chunsheng Yan
- Department
of Chemical and Biomolecular Engineering, Department of Chemistry and Biochemistry, Department of Molecular,
Cell, and Developmental Biology, and Howard Hughes Medical Institute, University of California, Los Angeles, California 90095, United States
| | - Wenyu Han
- Department
of Chemical and Biomolecular Engineering, Department of Chemistry and Biochemistry, Department of Molecular,
Cell, and Developmental Biology, and Howard Hughes Medical Institute, University of California, Los Angeles, California 90095, United States
| | - Qingyang Zhou
- Department
of Chemical and Biomolecular Engineering, Department of Chemistry and Biochemistry, Department of Molecular,
Cell, and Developmental Biology, and Howard Hughes Medical Institute, University of California, Los Angeles, California 90095, United States
| | - Kanji Niwa
- Department
of Chemical and Biomolecular Engineering, Department of Chemistry and Biochemistry, Department of Molecular,
Cell, and Developmental Biology, and Howard Hughes Medical Institute, University of California, Los Angeles, California 90095, United States
| | - Melody J. Tang
- Division of Chemistry
and Chemical Engineering, California Institute
of Technology, Pasadena, California 91125, United States
| | - Jessica E. Burch
- Division of Chemistry
and Chemical Engineering, California Institute
of Technology, Pasadena, California 91125, United States
| | - Yalong Zhang
- Department
of Chemical and Biomolecular Engineering, Department of Chemistry and Biochemistry, Department of Molecular,
Cell, and Developmental Biology, and Howard Hughes Medical Institute, University of California, Los Angeles, California 90095, United States
| | - David A. Delgadillo
- Division of Chemistry
and Chemical Engineering, California Institute
of Technology, Pasadena, California 91125, United States
| | - Zuodong Sun
- Department
of Chemical and Biomolecular Engineering, Department of Chemistry and Biochemistry, Department of Molecular,
Cell, and Developmental Biology, and Howard Hughes Medical Institute, University of California, Los Angeles, California 90095, United States
| | - Zhongshou Wu
- Department
of Chemical and Biomolecular Engineering, Department of Chemistry and Biochemistry, Department of Molecular,
Cell, and Developmental Biology, and Howard Hughes Medical Institute, University of California, Los Angeles, California 90095, United States
| | - Steven E. Jacobsen
- Department
of Chemical and Biomolecular Engineering, Department of Chemistry and Biochemistry, Department of Molecular,
Cell, and Developmental Biology, and Howard Hughes Medical Institute, University of California, Los Angeles, California 90095, United States
| | - Hosea Nelson
- Division of Chemistry
and Chemical Engineering, California Institute
of Technology, Pasadena, California 91125, United States
| | - K. N. Houk
- Department
of Chemical and Biomolecular Engineering, Department of Chemistry and Biochemistry, Department of Molecular,
Cell, and Developmental Biology, and Howard Hughes Medical Institute, University of California, Los Angeles, California 90095, United States
| | - Yi Tang
- Department
of Chemical and Biomolecular Engineering, Department of Chemistry and Biochemistry, Department of Molecular,
Cell, and Developmental Biology, and Howard Hughes Medical Institute, University of California, Los Angeles, California 90095, United States
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3
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High yield synthesis of nigerooligosaccharides by transglycosylation catalyzed by α-glucosidase TaAglA from Thermoplasma acidophilum. FOOD BIOSCI 2022. [DOI: 10.1016/j.fbio.2022.101582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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4
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Discovery of a Kojibiose Hydrolase by Analysis of Specificity-Determining Correlated Positions in Glycoside Hydrolase Family 65. Molecules 2021; 26:molecules26206321. [PMID: 34684901 PMCID: PMC8537180 DOI: 10.3390/molecules26206321] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 10/13/2021] [Accepted: 10/14/2021] [Indexed: 11/25/2022] Open
Abstract
The Glycoside Hydrolase Family 65 (GH65) is an enzyme family of inverting α-glucoside phosphorylases and hydrolases that currently contains 10 characterized enzyme specificities. However, its sequence diversity has never been studied in detail. Here, an in-silico analysis of correlated mutations was performed, revealing specificity-determining positions that facilitate annotation of the family’s phylogenetic tree. By searching these positions for amino acid motifs that do not match those found in previously characterized enzymes from GH65, several clades that may harbor new functions could be identified. Three enzymes from across these regions were expressed in E. coli and their substrate profile was mapped. One of those enzymes, originating from the bacterium Mucilaginibacter mallensis, was found to hydrolyze kojibiose and α-1,2-oligoglucans with high specificity. We propose kojibiose glucohydrolase as the systematic name and kojibiose hydrolase or kojibiase as the short name for this new enzyme. This work illustrates a convenient strategy for mapping the natural diversity of enzyme families and smartly mining the ever-growing number of available sequences in the quest for novel specificities.
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Alarico S, Nunes-Costa D, Silva A, Costa M, Macedo-Ribeiro S, Empadinhas N. A genuine mycobacterial thermophile: Mycobacterium hassiacum growth, survival and GpgS stability at near-pasteurization temperatures. MICROBIOLOGY-SGM 2021; 166:474-483. [PMID: 32100712 DOI: 10.1099/mic.0.000898] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Mycobacterium hassiacum is so far the most thermophilic among mycobacteria as it grows optimally at 50 °C and up to 65 °C in a glycerol-based medium, as verified in this study. Since this and other nontuberculous mycobacteria (NTM) thrive in diverse natural and artificial environments, from where they may access and infect humans, we deemed essential to probe M. hassiacum resistance to heat, a strategy routinely used to control microbial growth in water-supply systems, as well as in the food and drink industries. In addition to possibly being a threat in its own right in rare occasions, M. hassiacum is also a good surrogate for studying other NTM species more often associated with opportunistic infection, namely Mycobacterium avium and Mycobacterium abscessus as well as their strictly pathogenic counterparts Mycobacterium tuberculosis and Mycobacterium leprae. In this regard, this thermophilic species is likely to be useful as a source of stable proteins that may provide more detailed structures of potential drug targets. Here, we investigate M. hassiacum growth at near-pasteurization temperatures and at different pHs and also characterize its thermostable glucosyl-3-phosphoglycerate synthase (GpgS), an enzyme considered essential for M. tuberculosis growth and associated with both nitrogen starvation and thermal stress in different NTM species.
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Affiliation(s)
- Susana Alarico
- IIIUC - Institute for Interdisciplinary Research, University of Coimbra, Coimbra, Portugal.,CNC - Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Daniela Nunes-Costa
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,PDBEB - PhD Programme in Biomedicine and Experimental Biology, Institute for Interdisciplinary Research, University of Coimbra, Coimbra, Portugal
| | - Alexandra Silva
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.,IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
| | - Mafalda Costa
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Sandra Macedo-Ribeiro
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.,IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
| | - Nuno Empadinhas
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,IIIUC - Institute for Interdisciplinary Research, University of Coimbra, Coimbra, Portugal
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6
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Biochemical properties of Glu-SH3 as a family 13 glycoside hydrolase with remarkable substrate specificity for trehalose: Implications to sequence-based classification of CAZymes. Arch Biochem Biophys 2016; 603:1-9. [PMID: 27177969 DOI: 10.1016/j.abb.2016.05.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Revised: 04/13/2016] [Accepted: 05/09/2016] [Indexed: 11/24/2022]
Abstract
A novel glycoside hydrolase from Exiguobacterium sp. SH3 was characterized. The enzyme, designated as Glu-SH3, was predicted by in silico analysis to have structural similarity with members of oligo-1,6-glucosidase and trehalose-6-phosphate hydrolase subfamilies in the GH-13 family of glycoside hydrolases. The gene was expressed in Escherichia coli and the recombinant enzyme was purified as a His-tagged protein of about 60 kDa. The enzyme was shown to have remarkable substrate specificity for trehalose. The characteristic ability of Glu-SH3 to hydrolyze trehalose was ascertained by zymography, thin layer chromatography, and NMR spectroscopy. The maximum activity of Glu-SH3 was obtained at 35 °C and pH 7, but it was able to exhibit more than 90% of the activity within the pH range of 5-8. The Vmax and Km values were estimated to be 170 U and 4.5 mg ml(-1), respectively. By comparison with trehalases, Glu-SH3 with Kcat and Kcat/Km values of 1552 s(-1) and 119.4 mM(-1) s(-1) can be recognized as a very efficient trehalose-hydrolyzing glycosidase. Given the phylogeny and the substrate specificity of Glu-SH3, it may be assumed that the enzyme shares a common ancestor with oligo-1,6-glucosidases but have evolved distinctly to serve a physiological function in trehalose metabolism.
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7
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Zhou C, Xue Y, Ma Y. Evaluation and directed evolution for thermostability improvement of a GH 13 thermostable α-glucosidase from Thermus thermophilus TC11. BMC Biotechnol 2015; 15:97. [PMID: 26490269 PMCID: PMC4618444 DOI: 10.1186/s12896-015-0197-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2015] [Accepted: 08/19/2015] [Indexed: 11/24/2022] Open
Abstract
Background Thermal stable α-glucosidases with transglycosylation activity could be applied to the industrial production of oligosaccharides as well as conjugation of sugars to biologically useful materials. Therefore, α-glucosidases isolated from thermophiles have gained attention over the past decade. In this study, the characterization of a highly thermostable α-glucosidase and its thermostability improved mutant from newly isolated strain Thermus thermophilus TC11 were investigated. Results The recombinant α-glucosidase (TtAG) from Thermus thermophilus TC11 was expressed in Escherichia coli BL21 (DE3) and purified. The purified enzyme had a molecular mass of 184 kDa and consisted of 59-kDa subunits; it showed hydrolytic activity for pNP-α-d-glucopyranoside (pNPG), sucrose, trehalose, panose, and isomaltooligosaccharides and very low activity for maltose. The highest specific activity of 288.96 U/mg was observed for pNPG at 90 °C and pH 5.0; Pb2+ provided a 20 % activity increase. TtAG was stable at 70 °C for more than 7 h and had a half-life of 195 min at 80 °C and 130 min at 90 °C. Transglycosylation activity was also observed with sucrose and trehalose as substrates. TtAG showed differences on substrate specificity, transglycosylation, multimerization, effects of metal ions and optimal pH from other reported Thermus α-glucosidases. One single-substitution TtAG mutant Q10Y with improved thermostability was also obtained from random mutagenesis library. The site-saturation mutagenesis and structural modelling analysis indicated that Q10Y substitution stabilized TtAG structure via additional hydrogen bonding and hydrophobic interactions. Conclusion Our findings indicate that TtAG is a highly thermostable and more acidic α-glucosidase distinct from other reported Thermus α-glucosidases. And this work also provides new insights into the catalytic and thermal tolerance mechanisms of α-glucosidases, which may guide molecular engineering of α-glucosidase and other thermostable enzymes for industrial application. Electronic supplementary material The online version of this article (doi:10.1186/s12896-015-0197-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Cheng Zhou
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, No. 1 West Beichen Road, Chaoyang District, Beijing, 100101, China.,National Engineering Lab for Industrial Enzymes, Institute of Microbiology, Chinese Academy of Sciences, No. 1 West Beichen Road, Chaoyang District, Beijing, 100101, China
| | - Yanfen Xue
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, No. 1 West Beichen Road, Chaoyang District, Beijing, 100101, China.,National Engineering Lab for Industrial Enzymes, Institute of Microbiology, Chinese Academy of Sciences, No. 1 West Beichen Road, Chaoyang District, Beijing, 100101, China
| | - Yanhe Ma
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, No. 1 West Beichen Road, Chaoyang District, Beijing, 100101, China. .,National Engineering Lab for Industrial Enzymes, Institute of Microbiology, Chinese Academy of Sciences, No. 1 West Beichen Road, Chaoyang District, Beijing, 100101, China.
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8
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Nobre A, Alarico S, Maranha A, Mendes V, Empadinhas N. The molecular biology of mycobacterial trehalose in the quest for advanced tuberculosis therapies. MICROBIOLOGY-SGM 2014; 160:1547-1570. [PMID: 24858083 DOI: 10.1099/mic.0.075895-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Trehalose is a natural glucose disaccharide identified in the 19th century in fungi and insect cocoons, and later across the three domains of life. In members of the genus Mycobacterium, which includes the tuberculosis (TB) pathogen and over 160 species of nontuberculous mycobacteria (NTM), many of which are opportunistic pathogens, trehalose has been an important focus of research over the last 60 years. It is a crucial player in the assembly and architecture of the remarkable mycobacterial cell envelope as an element of unique highly antigenic glycolipids, namely trehalose dimycolate ('cord factor'). Free trehalose has been detected in the mycobacterial cytoplasm and occasionally in oligosaccharides with unknown function. TB and NTM infection statistics and death toll, the decline in immune responses in the aging population, human immunodeficiency virus/AIDS or other debilitating conditions, and the proliferation of strains with different levels of resistance to the dated drugs in use, all merge into a serious public-health threat urging more effective vaccines, efficient diagnostic tools and new drugs. This review deals with the latest findings on mycobacterial trehalose biosynthesis, catabolism, processing and recycling, as well with the ongoing quest for novel trehalose-related mechanisms to be targeted by novel TB therapeutics. In this context, the drug-discovery pipeline has recently included new lead compounds directed toward trehalose-related targets highlighting the potential of these pathways to stem the tide of rising drug resistance.
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Affiliation(s)
- Ana Nobre
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Susana Alarico
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Ana Maranha
- Biosciences PhD Program, Department of Life Sciences, University of Coimbra, Coimbra, Portugal.,CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Vitor Mendes
- Department of Biochemistry, University of Cambridge, Cambridge, UK.,CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Nuno Empadinhas
- III/UC-Institute for Interdisciplinary Research, University of Coimbra, Coimbra, Portugal.,CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
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9
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Lee NR, Lakshmanan M, Aggarwal S, Song JW, Karimi IA, Lee DY, Park JB. Genome-scale metabolic network reconstruction and in silico flux analysis of the thermophilic bacterium Thermus thermophilus HB27. Microb Cell Fact 2014; 13:61. [PMID: 24774833 PMCID: PMC4021367 DOI: 10.1186/1475-2859-13-61] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Accepted: 04/17/2014] [Indexed: 01/18/2023] Open
Abstract
Background Thermus thermophilus, an extremely thermophilic bacterium, has been widely recognized as a model organism for studying how microbes can survive and adapt under high temperature environment. However, the thermotolerant mechanisms and cellular metabolism still remains mostly unravelled. Thus, it is highly required to consider systems biological approaches where T. thermophilus metabolic network model can be employed together with high throughput experimental data for elucidating its physiological characteristics under such harsh conditions. Results We reconstructed a genome-scale metabolic model of T. thermophilus, iTT548, the first ever large-scale network of a thermophilic bacterium, accounting for 548 unique genes, 796 reactions and 635 unique metabolites. Our initial comparative analysis of the model with Escherichia coli has revealed several distinctive metabolic reactions, mainly in amino acid metabolism and carotenoid biosynthesis, producing relevant compounds to retain the cellular membrane for withstanding high temperature. Constraints-based flux analysis was, then, applied to simulate the metabolic state in glucose minimal and amino acid rich media. Remarkably, resulting growth predictions were highly consistent with the experimental observations. The subsequent comparative flux analysis under different environmental conditions highlighted that the cells consumed branched chain amino acids preferably and utilized them directly in the relevant anabolic pathways for the fatty acid synthesis. Finally, gene essentiality study was also conducted via single gene deletion analysis, to identify the conditional essential genes in glucose minimal and complex media. Conclusions The reconstructed genome-scale metabolic model elucidates the phenotypes of T. thermophilus, thus allowing us to gain valuable insights into its cellular metabolism through in silico simulations. The information obtained from such analysis would not only shed light on the understanding of physiology of thermophiles but also helps us to devise metabolic engineering strategies to develop T. thermophilus as a thermostable microbial cell factory.
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Affiliation(s)
| | | | | | | | | | - Dong-Yup Lee
- Department of Food Science & Engineering, Ewha Womans University, 11-1 Daehyun-dong, Seodaemun-gu, Seoul 120-750, Korea.
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A new bacterial hydrolase specific for the compatible solutes α-d-mannopyranosyl-(1→2)-d-glycerate and α-d-glucopyranosyl-(1→2)-d-glycerate. Enzyme Microb Technol 2013; 52:77-83. [DOI: 10.1016/j.enzmictec.2012.10.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2012] [Revised: 10/19/2012] [Accepted: 10/23/2012] [Indexed: 11/21/2022]
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11
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Sandoval M, Ferreras E, Pérez-Sánchez M, Berenguer J, Sinisterra JV, Hernaiz MJ. Screening of strains and recombinant enzymes from Thermus thermophilus for their use in disaccharide synthesis. ACTA ACUST UNITED AC 2012. [DOI: 10.1016/j.molcatb.2011.09.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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12
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Empadinhas N, Pereira PJB, Albuquerque L, Costa J, Sá-Moura B, Marques AT, Macedo-Ribeiro S, da Costa MS. Functional and structural characterization of a novel mannosyl-3-phosphoglycerate synthase from Rubrobacter xylanophilus reveals its dual substrate specificity. Mol Microbiol 2010; 79:76-93. [PMID: 21166895 DOI: 10.1111/j.1365-2958.2010.07432.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Rubrobacter xylanophilus is the only actinobacterium known to accumulate the organic solute mannosylglycerate (MG); moreover, the accumulation of MG is constitutive. The key enzyme for MG synthesis, catalysing the conversion of GDP-mannose (GDP-Man) and D-3-phosphoglycerate (3-PGA) into the phosphorylated intermediate mannosyl-3-phosphoglycerate and GDP, was purified from R. xylanophilus cell extracts and the corresponding gene was expressed in E. coli. Despite the related solute glucosylglycerate (GG) having never been detected in R. xylanophilus, the cell extracts and the pure recombinant mannosyl-3-phosphoglycerate synthase (MpgS) could also synthesize glucosyl-3-phosphoglycerate (GPG), the precursor of GG, in agreement with the higher homology of the novel MpgS towards GPG-synthesizing mycobacterial glucosyl-3-phosphoglycerate synthases (GpgS) than towards MpgSs from hyper/thermophiles, known to accumulate MG under salt or thermal stress. To understand the specificity and substrate ambiguity of this novel enzyme, we determined the crystal structure of the unliganded MpgS and of its complexes with the nucleotide and sugar donors, at 2.2, 2.8 and 2.5 Å resolution respectively. The first three-dimensional structures of a protein from this extremely gamma-radiation-resistant thermophile here reported show that MpgS (GT81 family) contains a GT-A like fold and clearly explain its nucleotide and sugar-donor specificity. In the GDP-Man complex, a flexible loop ((254) RQNRHQ(259) ), located close to the active site moves towards the incoming sugar moiety, providing the ligands for both magnesium ion co-ordination and sugar binding. A triple mutant of R. xylanophilus MpgS, mimicking the (206) PLAGE(210) loop stabilizing hydrogen bond network observed for mycobacterial GpgSs, reduces significantly the affinity to GDP-Man, implicating this loop in the sugar-donor discrimination.
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Affiliation(s)
- Nuno Empadinhas
- Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra, Portugal
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13
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Characterization of two novel alpha-glucosidases from Bifidobacterium breve UCC2003. Appl Environ Microbiol 2008; 75:1135-43. [PMID: 19114534 DOI: 10.1128/aem.02391-08] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Two alpha-glucosidase-encoding genes (agl1 and agl2) from Bifidobacterium breve UCC2003 were identified and characterized. Based on their similarity to characterized carbohydrate hydrolases, the Agl1 and Agl2 enzymes are both assigned to a subgroup of the glycosyl hydrolase family 13, the alpha-1,6-glucosidases (EC 3.2.1.10). Recombinant Agl1 and Agl2 into which a His(12) sequence was incorporated (Agl1(His) and Agl2(His), respectively) exhibited hydrolytic activity towards panose, isomaltose, isomaltotriose, and four sucrose isomers--palatinose, trehalulose, turanose, and maltulose--while also degrading trehalose and, to a lesser extent, nigerose. The preferred substrates for both enzymes were panose, isomaltose, and trehalulose. Furthermore, the pH and temperature optima for both enzymes were determined, showing that Agl1(His) exhibits higher thermo and pH optima than Agl2(His). The two purified alpha-1,6-glucosidases were also shown to have transglycosylation activity, synthesizing oligosaccharides from palatinose, trehalulose, trehalose, panose, and isomaltotriose.
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