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Zhang F, Liu J, Jiang L, Zheng Y, Yu L, Du L. Production of the siderophore lysochelin in rich media through maltose-promoted high-density growth of Lysobacter sp. 3655. Front Microbiol 2024; 15:1433983. [PMID: 38989020 PMCID: PMC11233812 DOI: 10.3389/fmicb.2024.1433983] [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: 05/17/2024] [Accepted: 06/10/2024] [Indexed: 07/12/2024] Open
Abstract
Siderophores are produced by bacteria in iron-restricted conditions. However, we found maltose could induce the biosynthesis of the siderophore lysochelin in Lysobacter sp. 3655 in rich media that are not compatible with siderophore production. Maltose markedly promoted cell growth, with over 300% increase in cell density (OD600) when LB medium was added with maltose (LBM). While lysochelin was not detectable when OD600 in LBM was below 5.0, the siderophore was clearly produced when OD600 reached 7.5 and dramatically increased when OD600 was 15.0. Coincidently, the transcription of lysochelin biosynthesis genes was remarkably enhanced following the increase of OD600. Conversely, the iron concentration in the cell culture dropped to 1.2 μM when OD600 reached 15.0, which was 6-fold lower than that in the starting medium. Moreover, mutants of the maltose-utilizing genes (orf2677 and orf2678) or quorum-sensing related gene orf644 significantly lowered the lysochelin yield. Transcriptomics analysis showed that the iron-utilizing/up-taking genes were up-regulated under high cell density. Accordingly, the transcription of lysochelin biosynthetic genes and the yield of lysochelin were stimulated when the iron-utilizing/up-taking genes were deleted. Finally, lysochelin biosynthesis was positively regulated by a TetR regulator (ORF3043). The lysochelin yield in orf3043 mutant decreased to 50% of that in the wild type and then restored in the complementary strain. Together, this study revealed a previously unrecognized mechanism for lysochelin biosynthetic regulation, by which the siderophore could still be massively produced in Lysobacter even grown in a rich culture medium. This finding could find new applications in large-scale production of siderophores in bacteria.
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Affiliation(s)
- Fang Zhang
- School of Life Sciences, Fujian Normal University, Fuzhou, Fujian, China
| | - Jia Liu
- School of Life Sciences, Fujian Normal University, Fuzhou, Fujian, China
| | - Lin Jiang
- School of Life Sciences, Fujian Normal University, Fuzhou, Fujian, China
| | - Yongbiao Zheng
- School of Life Sciences, Fujian Normal University, Fuzhou, Fujian, China
| | - Lingjun Yu
- School of Life Sciences, Fujian Normal University, Fuzhou, Fujian, China
| | - Liangcheng Du
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln, NE, United States
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2
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Singh L, Karthikeyan S, Thakur KG. Biochemical and structural characterization reveals Rv3400 codes for β-phosphoglucomutase in Mycobacterium tuberculosis. Protein Sci 2024; 33:e4943. [PMID: 38501428 PMCID: PMC10949319 DOI: 10.1002/pro.4943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 01/22/2024] [Accepted: 02/11/2024] [Indexed: 03/20/2024]
Abstract
Mycobacterium tuberculosis (Mtb) adapt to various host environments and utilize a variety of sugars and lipids as carbon sources. Among these sugars, maltose and trehalose, also play crucial role in bacterial physiology and virulence. However, some key enzymes involved in trehalose and maltose metabolism in Mtb are not yet known. Here we structurally and functionally characterized a conserved hypothetical gene Rv3400. We determined the crystal structure of Rv3400 at 1.7 Å resolution. The crystal structure revealed that Rv3400 adopts Rossmann fold and shares high structural similarity with haloacid dehalogenase family of proteins. Our comparative structural analysis suggested that Rv3400 could perform either phosphatase or pyrophosphatase or β-phosphoglucomutase (β-PGM) activity. Using biochemical studies, we further confirmed that Rv3400 performs β-PGM activity and hence, Rv3400 encodes for β-PGM in Mtb. Our data also confirm that Mtb β-PGM is a metal dependent enzyme having broad specificity for divalent metal ions. β-PGM converts β-D-glucose-1-phosphate to β-D-glucose-6-phosphate which is required for the generation of ATP and NADPH through glycolysis and pentose phosphate pathway, respectively. Using site directed mutagenesis followed by biochemical studies, we show that two Asp residues in the highly conserved DxD motif, D29 and D31, are crucial for enzyme activity. While D29A, D31A, D29E, D31E and D29N mutants lost complete activity, D31N mutant retained about 30% activity. This study further helps in understanding the role of β-PGM in the physiology of Mtb.
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Affiliation(s)
- Latika Singh
- Division of Protein Science and EngineeringCouncil of Scientific and Industrial Research—Institute of Microbial Technology (CSIR‐IMTECH)ChandigarhIndia
| | - Subramanian Karthikeyan
- Division of Protein Science and EngineeringCouncil of Scientific and Industrial Research—Institute of Microbial Technology (CSIR‐IMTECH)ChandigarhIndia
| | - Krishan Gopal Thakur
- Division of Protein Science and EngineeringCouncil of Scientific and Industrial Research—Institute of Microbial Technology (CSIR‐IMTECH)ChandigarhIndia
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3
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Shrestha P, Karmacharya J, Han SR, Lee JH, Oh TJ. Elucidation of bacterial trehalose-degrading trehalase and trehalose phosphorylase: physiological significance and its potential applications. Glycobiology 2024; 34:cwad084. [PMID: 37847605 PMCID: PMC10969515 DOI: 10.1093/glycob/cwad084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 10/11/2023] [Accepted: 10/11/2023] [Indexed: 10/19/2023] Open
Abstract
Bacteria possess diverse metabolic and genetic processes, resulting in the inability of certain bacteria to degrade trehalose. However, some bacteria do have the capability to degrade trehalose, utilizing it as a carbon source, and for defense against environmental stress. Trehalose, a disaccharide, serves as a carbon source for many bacteria, including some that are vital for pathogens. The degradation of trehalose is carried out by enzymes like trehalase (EC 3.2.1.28) and trehalose phosphorylase (EC 2.4.1.64/2.4.1.231), which are classified under the glycoside hydrolase families GH37, GH15, and GH65. Numerous studies and reports have explored the physiological functions, recombinant expression, enzymatic characteristics, and potential applications of these enzymes. However, further research is still being conducted to understand their roles in bacteria. This review aims to provide a comprehensive summary of the current understanding of trehalose degradation pathways in various bacteria, focusing on three key areas: (i) identifying different trehalose-degrading enzymes in Gram-positive and Gram-negative bacteria, (ii) elucidating the mechanisms employed by trehalose-degrading enzymes belonging to the glycoside hydrolases GH37, GH15, and GH65, and (iii) discussing the potential applications of these enzymes in different sectors. Notably, this review emphasizes the bacterial trehalose-degrading enzymes, specifically trehalases (GH37, GH15, and GH65) and trehalose phosphorylases (GH65), in both Gram-positive and Gram-negative bacteria, an aspect that has not been highlighted before.
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Affiliation(s)
- Prasansah Shrestha
- Department of Life Sciences and Biochemical Engineering, Graduate School, Sun Moon University, 70 Sunmoon-ro 221beon-gil, Tangjeong-myeon, Asan-si, Chungcheongnam-do, 31460, South Korea
| | - Jayram Karmacharya
- Department of Life Sciences and Biochemical Engineering, Graduate School, Sun Moon University, 70 Sunmoon-ro 221beon-gil, Tangjeong-myeon, Asan-si, Chungcheongnam-do, 31460, South Korea
| | - So-Ra Han
- Department of Life Sciences and Biochemical Engineering, Graduate School, Sun Moon University, 70 Sunmoon-ro 221beon-gil, Tangjeong-myeon, Asan-si, Chungcheongnam-do, 31460, South Korea
- Genome-based Bio-IT Convergence Institute, 70 Sunmoon-ro 221beon-gil, Tangjeong-myeon Asan-si, Chungcheongnam-do, 31460, South Korea
| | - Jun Hyuck Lee
- Research Unit of Cryogenic Novel Materials, Korea Polar Research Institute, 26 Songdomirae-ro, Yeonsu-gu, Incheon 21990, South Korea
| | - Tae-Jin Oh
- Department of Life Sciences and Biochemical Engineering, Graduate School, Sun Moon University, 70 Sunmoon-ro 221beon-gil, Tangjeong-myeon, Asan-si, Chungcheongnam-do, 31460, South Korea
- Genome-based Bio-IT Convergence Institute, 70 Sunmoon-ro 221beon-gil, Tangjeong-myeon Asan-si, Chungcheongnam-do, 31460, South Korea
- Department of Pharmaceutical Engineering and Biotechnology, Sun Moon University, 70 Sunmoon-ro 221beon-gil, Tangjeong-myeon, Asan-si, Chungcheongnam-do 31460, South Korea
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4
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Harlé O, Niay J, Parayre S, Nicolas A, Henry G, Maillard MB, Valence F, Thierry A, Guédon É, Falentin H, Deutsch SM. Deciphering the metabolism of Lactobacillus delbrueckii subsp. delbrueckii during soy juice fermentation using phenotypic and transcriptional analysis. Appl Environ Microbiol 2024; 90:e0193623. [PMID: 38376234 PMCID: PMC10952386 DOI: 10.1128/aem.01936-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Accepted: 01/03/2024] [Indexed: 02/21/2024] Open
Abstract
In the context of sustainable diet, the development of soy-based yogurt fermented with lactic acid bacteria is an attractive alternative to dairy yogurts. To decipher the metabolism of Lactobacillus delbrueckii subsp. delbrueckii during soy juice (SJ) fermentation, the whole genome of the strain CIRM-BIA865 (Ld865) was sequenced and annotated. Then Ld865 was used to ferment SJ. Samples were analyzed throughout fermentation for their cell number, carbohydrate, organic acid, free amino acid, and volatile compound contents. Despite acidification, the number of Ld865 cells did not rise, and microscopic observations revealed the elongation of cells from 3.6 µm (inoculation) to 36.9 µm (end of fermentation). This elongation was observed in SJ but not in laboratory-rich medium MRS. Using transcriptomic analysis, we showed that the biosynthesis genes of peptidoglycan and membrane lipids were stably expressed, in line with the cell elongation observed, whereas no genes implicated in cell division were upregulated. Among the main sugars available in SJ (sucrose, raffinose, and stachyose), Ld865 only used sucrose. The transcriptomic analysis showed that Ld865 implemented the two transport systems that it contains to import sucrose: a PTS system and an ABC transporter. To fulfill its nitrogen needs, Ld865 probably first consumed the free amino acids of the SJ and then implemented different oligopeptide transporters and proteolytic/peptidase enzymes. In conclusion, this study showed that Ld865 enables fast acidification of SJ, despite the absence of cell division, leads to a product rich in free amino acids, and also leads to the production of aromatic compounds of interest. IMPORTANCE To reduce the environmental and health concerns related to food, an alternative diet is recommended, containing 50% of plant-based proteins. Soy juice, which is protein rich, is a relevant alternative to animal milk, for the production of yogurt-like products. However, soy "beany" and "green" off-flavors limit the consumption of such products. The lactic acid bacteria (LAB) used for fermentation can help to improve the organoleptic properties of soy products. But metabolic data concerning LAB adapted to soy juice are lacking. The aim of this study was, thus, to decipher the metabolism of Lactobacillus delbrueckii subsp. delbrueckii during fermentation of a soy juice, based on a multidisciplinary approach. This result will contribute to give tracks for a relevant selection of starter. Indeed, the improvement of the organoleptic properties of these types of products could help to promote plant-based proteins in our diet.
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Affiliation(s)
- Olivier Harlé
- INRAE, Institut Agro, STLO, Rennes, France
- Olga-Triballat Noyal, R&D UF, Noyal-sur-Vilaine, France
| | - Jérôme Niay
- Olga-Triballat Noyal, R&D UF, Noyal-sur-Vilaine, France
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5
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Allomorphy as a mechanism of post-translational control of enzyme activity. Nat Commun 2020; 11:5538. [PMID: 33139716 PMCID: PMC7608592 DOI: 10.1038/s41467-020-19215-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 09/23/2020] [Indexed: 11/08/2022] Open
Abstract
Enzyme regulation is vital for metabolic adaptability in living systems. Fine control of enzyme activity is often delivered through post-translational mechanisms, such as allostery or allokairy. β-phosphoglucomutase (βPGM) from Lactococcus lactis is a phosphoryl transfer enzyme required for complete catabolism of trehalose and maltose, through the isomerisation of β-glucose 1-phosphate to glucose 6-phosphate via β-glucose 1,6-bisphosphate. Surprisingly for a gatekeeper of glycolysis, no fine control mechanism of βPGM has yet been reported. Herein, we describe allomorphy, a post-translational control mechanism of enzyme activity. In βPGM, isomerisation of the K145-P146 peptide bond results in the population of two conformers that have different activities owing to repositioning of the K145 sidechain. In vivo phosphorylating agents, such as fructose 1,6-bisphosphate, generate phosphorylated forms of both conformers, leading to a lag phase in activity until the more active phosphorylated conformer dominates. In contrast, the reaction intermediate β-glucose 1,6-bisphosphate, whose concentration depends on the β-glucose 1-phosphate concentration, couples the conformational switch and the phosphorylation step, resulting in the rapid generation of the more active phosphorylated conformer. In enabling different behaviours for different allomorphic activators, allomorphy allows an organism to maximise its responsiveness to environmental changes while minimising the diversion of valuable metabolites. β-phosphoglucomutase (βPGM) from Lactococcus lactis is a phosphoryl transfer enzyme required for catabolism of trehalose and maltose. Coupled analyses of multiple βPGM structures and enzymatic activity lead to the proposal of allomorphy — a post-translational mechanism controlling enzyme activity.
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6
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Cruz-Navarrete FA, Baxter NJ, Wood HP, Hounslow AM, Waltho JP. 1H, 15N and 13C backbone resonance assignments of the P146A variant of β-phosphoglucomutase from Lactococcus lactis in its substrate-free form. BIOMOLECULAR NMR ASSIGNMENTS 2019; 13:349-356. [PMID: 31396843 PMCID: PMC6713671 DOI: 10.1007/s12104-019-09904-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 07/20/2019] [Indexed: 06/10/2023]
Abstract
β-Phosphoglucomutase (βPGM) is a magnesium-dependent phosphoryl transfer enzyme that catalyses the reversible isomerisation of β-glucose 1-phosphate and glucose 6-phosphate, via two phosphoryl transfer steps and a β-glucose 1,6-bisphosphate intermediate. Substrate-free βPGM is an essential component of the catalytic cycle and an understanding of its dynamics would present significant insights into βPGM functionality, and enzyme catalysed phosphoryl transfer in general. Previously, 30 residues around the active site of substrate-free βPGMWT were identified as undergoing extensive millisecond dynamics and were unassignable. Here we report 1H, 15N and 13C backbone resonance assignments of the P146A variant (βPGMP146A) in its substrate-free form, where the K145-A146 peptide bond adopts a trans conformation in contrast to all crystal structures of βPGMWT, where the K145-P146 peptide bond is cis. In βPGMP146A millisecond dynamics are suppressed for all but 17 residues, allowing 92% of backbone resonances to be assigned. Secondary structure predictions using TALOS-N reflect βPGM crystal structures, and a chemical shift comparison between substrate-free βPGMP146A and βPGMWT confirms that the solution conformations are very similar, except for the D137-A147 loop. Hence, the isomerisation state of the 145-146 peptide bond has little effect on structure but the cis conformation triggers millisecond dynamics in the hinge (V12-T16), the nucleophile (D8) and residues that coordinate the transferring phosphate group (D8 and S114-S116), and the D137-A147 loop (V141-A142 and K145). These millisecond dynamics occur in addition to those for residues involved in coordinating the catalytic MgII ion and the L44-L53 loop responsible for substrate discrimination.
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Affiliation(s)
- F Aaron Cruz-Navarrete
- Department of Molecular Biology and Biotechnology, Krebs Institute for Biomolecular Research, The University of Sheffield, Firth Court, Western Bank, Sheffield, S10 2TN, UK
| | - Nicola J Baxter
- Department of Molecular Biology and Biotechnology, Krebs Institute for Biomolecular Research, The University of Sheffield, Firth Court, Western Bank, Sheffield, S10 2TN, UK
- Manchester Institute of Biotechnology and School of Chemistry, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK
| | - Henry P Wood
- Department of Molecular Biology and Biotechnology, Krebs Institute for Biomolecular Research, The University of Sheffield, Firth Court, Western Bank, Sheffield, S10 2TN, UK
| | - Andrea M Hounslow
- Department of Molecular Biology and Biotechnology, Krebs Institute for Biomolecular Research, The University of Sheffield, Firth Court, Western Bank, Sheffield, S10 2TN, UK
| | - Jonathan P Waltho
- Department of Molecular Biology and Biotechnology, Krebs Institute for Biomolecular Research, The University of Sheffield, Firth Court, Western Bank, Sheffield, S10 2TN, UK.
- Manchester Institute of Biotechnology and School of Chemistry, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK.
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7
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Zhu JS, Stiers KM, Winter SM, Garcia AD, Versini AF, Beamer LJ, Jakeman DL. Synthesis, Derivatization, and Structural Analysis of Phosphorylated Mono-, Di-, and Trifluorinated d-Gluco-heptuloses by Glucokinase: Tunable Phosphoglucomutase Inhibition. ACS OMEGA 2019; 4:7029-7037. [PMID: 31179410 PMCID: PMC6547622 DOI: 10.1021/acsomega.9b00008] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Accepted: 04/08/2019] [Indexed: 05/16/2023]
Abstract
Glucokinase phosphorylated a series of C-1 fluorinated α-d-gluco-heptuloses. These phosphorylated products were discovered to be inhibitors of α-phosphomannomutase/phosphoglucomutase (αPMM/PGM) and β-phosphoglucomutase (βPGM). Inhibition potency with both mutases inversely correlated to the degree of fluorination. Structural analysis with αPMM demonstrated the inhibitor binding to the active site, with the phosphate in the phosphate binding site and the anomeric hydroxyl directed to the catalytic site.
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Affiliation(s)
- Jian-She Zhu
- College
of Pharmacy, Dalhousie University, 5968 College Street, Halifax, Nova Scotia B3H 4R2, Canada
| | - Kyle M. Stiers
- Biochemistry
Department, University of Missouri, 117 Schweitzer Hall, Columbia, Missouri 65211, United States
| | - Sherany M. Winter
- College
of Pharmacy, Dalhousie University, 5968 College Street, Halifax, Nova Scotia B3H 4R2, Canada
- Department
of Chemistry, Hogeschool Leiden (UAS Leiden), Zernikedreef 11, CK Leiden 2333, The Netherlands
| | - Anthony D. Garcia
- College
of Pharmacy, Dalhousie University, 5968 College Street, Halifax, Nova Scotia B3H 4R2, Canada
- École
Nationale Supérieure de Chimie de Rennes, 11 Allée de Beaulieu, CS 50837, Rennes Cedex 7 35708, France
| | - Antoine F. Versini
- College
of Pharmacy, Dalhousie University, 5968 College Street, Halifax, Nova Scotia B3H 4R2, Canada
- École
Supérieure de Physique et de Chimie Industrielles de la Ville
de Paris, 10 rue Vauquelin, Paris 75005, France
| | - Lesa J. Beamer
- College
of Pharmacy, Dalhousie University, 5968 College Street, Halifax, Nova Scotia B3H 4R2, Canada
- E-mail: (L.J.B.)
| | - David L. Jakeman
- College
of Pharmacy, Dalhousie University, 5968 College Street, Halifax, Nova Scotia B3H 4R2, Canada
- Department
of Chemistry, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
- E-mail: (D.L.J.)
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8
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Zhang C, Allen KN, Dunaway-Mariano D. Mechanism of Substrate Recognition and Catalysis of the Haloalkanoic Acid Dehalogenase Family Member α-Phosphoglucomutase. Biochemistry 2018; 57:4504-4517. [PMID: 29952545 PMCID: PMC10725300 DOI: 10.1021/acs.biochem.8b00396] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
α-Phosphoglucomutase (αPGM), in its phosphorylated state, catalyzes the interconversion of α-d-glucose 1-phosphate and α-d-glucose 6-phosphate. The αPGM of Lactococcus lactis is a type C2B member of the haloalkanoic acid dehalogenase (HAD) enzyme family and is comprised of a Rossmann-fold catalytic domain and inserted α/β-fold cap domain. The active site is formed at the domain-domain interface. Herein, we report the results from a kinetic-based study of L. lactis αPGM catalysis, which demonstrate enzyme activation by autocatalyzed phosphorylation of Asp8 with αG1P, the intermediacy of αG1,6bisP in the phospho Ll-αPGM-catalyzed conversion of αG1P to G6P, and the reorientation of the αG1,6bisP intermediate via dissociation to solvent and rebinding. In order to provide insight into the structural determinants of L. lactis αPGM substrate recognition and catalysis, metal cofactor and substrate specificities were determined as were the contributions made by active-site residues toward catalytic efficiency. Lastly, the structure and catalytic mechanism of L. lactis αPGM are compared with those of HAD family phosphomutases L. lactis β-phosphoglucomutase and eukayotic α-phosphomannomutase to provide insight into the evolution of phosphohexomutases from HAD family phosphatases.
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Affiliation(s)
- Chunchun Zhang
- Testing & Analytical Center, Sichuan University, Chengdu, Sichuan 610064, P. R. China
| | - Karen N. Allen
- Department of Chemistry, Boston University, Boston MA 02215-2521
| | - Debra Dunaway-Mariano
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131
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9
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Dimopoulou M, Raffenne J, Claisse O, Miot-Sertier C, Iturmendi N, Moine V, Coulon J, Dols-Lafargue M. Oenococcus oeni Exopolysaccharide Biosynthesis, a Tool to Improve Malolactic Starter Performance. Front Microbiol 2018; 9:1276. [PMID: 29946314 PMCID: PMC6006919 DOI: 10.3389/fmicb.2018.01276] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 05/25/2018] [Indexed: 01/01/2023] Open
Abstract
Oenococcus oeni is the lactic acid bacterium that most commonly drives malolactic fermentation (MLF) in wine. Though the importance of MLF in terms of wine microbial stability and sensory improvement is well established, it remains a winemaking step not so easy to control. O. oeni displays many adaptation tools to resist the harsh wine conditions which explain its natural dominance at this stage of winemaking. Previous findings showed that capsular polysaccharides and endogenous produced dextran increased the survival rate and the conservation time of malolactic starters. In this paper, we showed that exopolysaccharides specific production rates were increased in the presence of single stressors relevant to wine (pH, ethanol). The transcription of the associated genes was investigated in distinct O. oeni strains. The conditions in which eps genes and EPS synthesis were most stimulated were then evaluated for the production of freeze dried malolactic starters, for acclimation procedures and for MLF efficiency. Sensory analysis tests on the resulting wines were finally performed.
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Affiliation(s)
- Maria Dimopoulou
- Université de Bordeaux, EA 4577 Œnologie, INRA, USC 1366, ISVV, Bordeaux INP, Villenave-d'Ornon, France
| | - Jerôme Raffenne
- Université de Bordeaux, EA 4577 Œnologie, INRA, USC 1366, ISVV, Bordeaux INP, Villenave-d'Ornon, France
| | - Olivier Claisse
- Université de Bordeaux, EA 4577 Œnologie, INRA, USC 1366, ISVV, Bordeaux INP, Villenave-d'Ornon, France
| | - Cécile Miot-Sertier
- Université de Bordeaux, EA 4577 Œnologie, INRA, USC 1366, ISVV, Bordeaux INP, Villenave-d'Ornon, France
| | | | | | | | - Marguerite Dols-Lafargue
- Université de Bordeaux, EA 4577 Œnologie, INRA, USC 1366, ISVV, Bordeaux INP, Villenave-d'Ornon, France
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10
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Awad FN, Kulinich A, Yao MJ, Duan XC, Cai ZP, Gu B, Liu L, Voglmeir J. Enzymatic glycosylation of indoxyglycosides catalyzed by a novel maltose phosphorylase from Emticicia oligotrophica. J Carbohydr Chem 2016. [DOI: 10.1080/07328303.2016.1238479] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Faisal Nureldin Awad
- Glycomics and Glycan Bioengineering Research Center (GGBRC), College of Food Science and Technology, Nanjing Agricultural University, Nanjing, People's Republic of China
- National Food Research Centre, Khartoum North, Sudan
| | - Anna Kulinich
- Glycomics and Glycan Bioengineering Research Center (GGBRC), College of Food Science and Technology, Nanjing Agricultural University, Nanjing, People's Republic of China
| | - Ming Jun Yao
- Glycomics and Glycan Bioengineering Research Center (GGBRC), College of Food Science and Technology, Nanjing Agricultural University, Nanjing, People's Republic of China
| | - Xu Chu Duan
- Glycomics and Glycan Bioengineering Research Center (GGBRC), College of Food Science and Technology, Nanjing Agricultural University, Nanjing, People's Republic of China
| | - Zhi Peng Cai
- Glycomics and Glycan Bioengineering Research Center (GGBRC), College of Food Science and Technology, Nanjing Agricultural University, Nanjing, People's Republic of China
| | - Bin Gu
- Glycomics and Glycan Bioengineering Research Center (GGBRC), College of Food Science and Technology, Nanjing Agricultural University, Nanjing, People's Republic of China
| | - Li Liu
- Glycomics and Glycan Bioengineering Research Center (GGBRC), College of Food Science and Technology, Nanjing Agricultural University, Nanjing, People's Republic of China
- Qlyco Ltd., Nanjing, People's Republic of China
| | - Josef Voglmeir
- Glycomics and Glycan Bioengineering Research Center (GGBRC), College of Food Science and Technology, Nanjing Agricultural University, Nanjing, People's Republic of China
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11
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Cimini D, Carlino E, Giovane A, Argenzio O, Dello Iacono I, De Rosa M, Schiraldi C. Engineering a branch of the UDP-precursor biosynthesis pathway enhances the production of capsular polysaccharide in Escherichia coli O5:K4:H4. Biotechnol J 2015; 10:1307-15. [PMID: 26153362 DOI: 10.1002/biot.201400602] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Revised: 05/27/2015] [Accepted: 07/02/2015] [Indexed: 11/06/2022]
Abstract
Escherichia coli K4 produces a capsule with a chemical structure that resembles chondroitin, a molecule with established chondro protective properties. The endogenous genes pgm and galU are involved in the biosynthesis of UDP-glucose which is a critical intermediate in carbohydrate metabolism and biochemical precursor of UDP-glucuronic acid. Together with UDP-N-acetylgalactosamine, UDP-glucuronic acid is used as sugar donor for capsule biosynthesis. The aim of the study was to evaluate how a change in the pathways leading to UDP-glucuronic acid biosynthesis affected capsular polysaccharide production. One additional copy of pgm and galU was introduced in E. coli K4 and in the previously described recombinant strain EcK4r3. A microbioreactor was used to analyse strain performance with parallel batch experiments, demonstrating increased polysaccharide concentrations and providing data that are comparable to those obtained in larger fermenters. Further experiments on a glutamine enriched medium showed an additional 45% increase of capsule production, maybe indicating the need to balance both branches leading to polymer biosynthesis in order to maximize yields. In the effort towards the establishment of a feasible bio-chondroitin production process this study provides information on how the availability of sugar precursors impacts polysaccharide biosynthesis in E. coli K4, a complex unexplored aspect of a multifaceted process.
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Affiliation(s)
- Donatella Cimini
- Department of Experimental Medicine, Section of Biotechnology and Molecular Biology, Second University of Naples, Naples, Italy.
| | - Elisabetta Carlino
- Department of Experimental Medicine, Section of Biotechnology and Molecular Biology, Second University of Naples, Naples, Italy
| | - Alfonso Giovane
- Department of Biochemistry Biophisics and General Pathology, Second University of Naples, Naples, Italy
| | - Ottavia Argenzio
- Department of Experimental Medicine, Section of Biotechnology and Molecular Biology, Second University of Naples, Naples, Italy
| | - Ileana Dello Iacono
- Department of Experimental Medicine, Section of Biotechnology and Molecular Biology, Second University of Naples, Naples, Italy
| | - Mario De Rosa
- Department of Experimental Medicine, Section of Biotechnology and Molecular Biology, Second University of Naples, Naples, Italy
| | - Chiara Schiraldi
- Department of Experimental Medicine, Section of Biotechnology and Molecular Biology, Second University of Naples, Naples, Italy.
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12
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Buckley AA, Faustoferri RC, Quivey RG. β-Phosphoglucomutase contributes to aciduricity in Streptococcus mutans. MICROBIOLOGY-SGM 2014; 160:818-827. [PMID: 24509501 DOI: 10.1099/mic.0.075754-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Streptococcus mutans encounters an array of sugar moieties within the oral cavity due to a varied human diet. One such sugar is β-d-glucose 1-phosphate (βDG1P), which must be converted to glucose 6-phosphate (G6P) before further metabolism to lactic acid. The conversion of βDG1P to G6P is mediated by β-phosphoglucomutase, which has not been previously observed in any oral streptococci, but has been extensively characterized and the gene designated pgmB in Lactococcus lactis. An orthologue was identified in S. mutans, SMU.1747c, and deletion of the gene resulted in the inability of the deletion strain to convert βDG1P to G6P, indicating that SMU.1747c is a β-phosphoglucomutase and should be designated pgmB. In this study, we sought to characterize how deletion of pgmB affected known virulence factors of S. mutans, specifically acid tolerance. The ΔpgmB strain showed a decreased ability to survive acid challenge. Additionally, the strain lacking β-phosphoglucomutase had a diminished glycolytic profile compared with the parental strain. Deletion of pgmB had a negative impact on the virulence of S. mutans in the Galleria mellonella (greater wax worm) animal model. Our results indicate that pgmB plays a role at the juncture of carbohydrate metabolism and virulence.
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Affiliation(s)
- Andrew A Buckley
- Department of Microbiology & Immunology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA
| | - Roberta C Faustoferri
- Center for Oral Biology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA
| | - Robert G Quivey
- Center for Oral Biology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA.,Department of Microbiology & Immunology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA
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13
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Nogly P, Matias PM, de Rosa M, Castro R, Santos H, Neves AR, Archer M. High-resolution structure of an atypical α-phosphoglucomutase related to eukaryotic phosphomannomutases. ACTA CRYSTALLOGRAPHICA SECTION D: BIOLOGICAL CRYSTALLOGRAPHY 2013; 69:2008-16. [DOI: 10.1107/s0907444913017046] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Accepted: 06/19/2013] [Indexed: 11/10/2022]
Abstract
The first structure of a bacterial α-phosphoglucomutase with an overall fold similar to eukaryotic phosphomannomutases is reported. Unlike most α-phosphoglucomutases within the α-D-phosphohexomutase superfamily, it belongs to subclass IIb of the haloacid dehalogenase superfamily (HADSF). It catalyzes the reversible conversion of α-glucose 1-phosphate to glucose 6-phosphate. The crystal structure of α-phosphoglucomutase fromLactococcus lactis(APGM) was determined at 1.5 Å resolution and contains a sulfate and a glycerol bound at the enzyme active site that partially mimic the substrate. A dimeric form of APGM is present in the crystal and in solution, an arrangement that may be functionally relevant. The catalytic mechanism of APGM and its strict specificity towards α-glucose 1-phosphate are discussed.
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14
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Avetisyan A, Jensen JB, Huser T. Monitoring Trehalose Uptake and Conversion by Single Bacteria using Laser Tweezers Raman Spectroscopy. Anal Chem 2013; 85:7264-70. [DOI: 10.1021/ac4011638] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- Anna Avetisyan
- Department
for Arctic and Marine
Biology, University of Tromsø, N-9037
Tromsø, Norway
| | - John Beck Jensen
- Department
for Arctic and Marine
Biology, University of Tromsø, N-9037
Tromsø, Norway
| | - Thomas Huser
- NSF
Center for Biophotonics
Science and Technology, University of California, Davis, Sacramento, California, United States
- Biomolecular Photonics, Department
of Physics, University of Bielefeld, 33501
Bielefeld, Germany
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15
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Loranger MW, Beaton SA, Lines KL, Jakeman DL. Thiophosphate and thiophosphonate analogues of glucose-1-phosphate: synthesis and enzymatic activity with a thymidylyltransferase. Carbohydr Res 2013; 379:43-50. [PMID: 23872276 DOI: 10.1016/j.carres.2013.06.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Revised: 06/10/2013] [Accepted: 06/11/2013] [Indexed: 11/17/2022]
Abstract
Synthetic methods were investigated for the preparation of O and S-glucosyl thiophosphates and glucosyl 1C-thiophosphonate. Four protected glucosyl thiophosphate compounds were synthesized and characterized as precursors to glucose 1-thiophosphate. The effect of various reaction conditions and the nature of the carbohydrate and thiophosphate protecting groups and how they impact both the yields and α/β diastereoselectivity of the glucosyl thiophosphate products were explored. A novel isomerization from an O-linked to S-linked glucosyl thiophosphate was observed. α-D-Glucose-1C-thiophosphonate was synthesized and evaluated as a substrate for the thymidylyltransferase, Cps2L. Tandem mass spectrometric analysis determined the position of sulfur in the sugar nucleotide product.
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Affiliation(s)
- Matthew W Loranger
- Department of Chemistry, Dalhousie University, Halifax, Nova Scotia, Canada
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16
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The thuEFGKAB operon of rhizobia and agrobacterium tumefaciens codes for transport of trehalose, maltitol, and isomers of sucrose and their assimilation through the formation of their 3-keto derivatives. J Bacteriol 2013; 195:3797-807. [PMID: 23772075 DOI: 10.1128/jb.00478-13] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The thu operon (thuEFGKAB) in Sinorhizobium meliloti codes for transport and utilization functions of the disaccharide trehalose. Sequenced genomes of members of the Rhizobiaceae reveal that some rhizobia and Agrobacterium possess the entire thu operon in similar organizations and that Mesorhizobium loti MAFF303099 lacks the transport (thuEFGK) genes. In this study, we show that this operon is dedicated to the transport and assimilation of maltitol and isomers of sucrose (leucrose, palatinose, and trehalulose) in addition to trehalulose, not only in S. meliloti but also in Agrobacterium tumefaciens. By using genetic complementation, we show that the thuAB genes of S. meliloti, M. loti, and A. tumefaciens are functionally equivalent. Further, we provide both genetic and biochemical evidence to show that these bacteria assimilate these disaccharides by converting them to their respective 3-keto derivatives and that the thuAB genes code for this ketodisaccharide-forming enzyme(s). Formation of 3-ketotrehalose in real time in live S. meliloti is shown through Raman spectroscopy. The presence of an additional ketodisaccharide-forming pathway(s) in A. tumefaciens is also indicated. To our knowledge, this is the first report to identify the genes that code for the conversion of disaccharides to their 3-ketodisaccharide derivatives in any organism.
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17
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Dimopoulou M, Hazo L, Dols-Lafargue M. Exploration of phenomena contributing to the diversity of Oenococcus oeni exopolysaccharides. Int J Food Microbiol 2011; 153:114-22. [PMID: 22119266 DOI: 10.1016/j.ijfoodmicro.2011.10.024] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2011] [Revised: 10/13/2011] [Accepted: 10/29/2011] [Indexed: 11/19/2022]
Abstract
Many food-grade bacteria produce exopolysaccharides (EPS) that may modify the food texture or affect their survival rate during food processing. This is the case of O. oeni, a bacterial species who drives malolactic fermentation in wine. The five strains analyzed in the present study all display both isolated genes dedicated to homopolysaccharide synthesis and gene clusters potentially associated with heteropolysaccharide synthesis. The number of isolated glycosyltransferase gene present and the gene composition of one of the operons change from one strain to the other. The soluble EPS yields and the EPS monomer composition vary depending on the strain and or the medium composition. O. oeni appears as a bacterium able to synthesize both homo and heteropolysaccharides. This unique property has rarely been described. Moreover, the abundance of the genetic determinants associated with EPS metabolism suggests that it is very important for the adaptation of the bacteria to wine.
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Affiliation(s)
- Maria Dimopoulou
- Université de Bordeaux, IPB, ISVV, EA 4602, Unité de recherche OENOLOGIE, INRA USC 1219, 210 chemin de leysotte, 33882 Villenave d'Ornon cedex, France
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18
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Genetic response to bacteriophage infection in Lactococcus lactis reveals a four-strand approach involving induction of membrane stress proteins, D-alanylation of the cell wall, maintenance of proton motive force, and energy conservation. J Virol 2011; 85:12032-42. [PMID: 21880765 DOI: 10.1128/jvi.00275-11] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In this study, whole-genome microarrays were used to gain insights into the global molecular response of Lactococcus lactis subsp. lactis IL1403 at an early stage of infection with the lytic phage c2. The bacterium differentially regulated the expression of 61 genes belonging to 14 functional categories, including cell envelope processes (12 genes), regulatory functions (11 genes), and carbohydrate metabolism (7 genes). The nature of these genes suggests a complex response involving four main mechanisms: (i) induction of membrane stress proteins, (ii) d-alanylation of cell wall lipoteichoic acids (LTAs), (iii) maintenance of the proton motive force (PMF), and (iv) energy conservation. The phage presence is sensed as a membrane stress in L. lactis subsp. lactis IL1403, which activated a cell wall-targeted response probably orchestrated by the concerted action of membrane phage shock protein C-like homologues, the global regulator SpxB, and the two-component system CesSR. The bacterium upregulated genes (ddl and dltABCD) responsible for incorporation of d-alanine esters into LTAs, an event associated with increased resistance to phage attack in Gram-positive bacteria. The expression of genes (yshC, citE, citF) affecting both PMF components was also regulated to restore the physiological PMF, which was disrupted following phage infection. While mobilizing the response to the phage-mediated stress, the bacterium activated an energy-saving program by repressing growth-related functions and switching to anaerobic respiration, probably to sustain the PMF and the overall cell response to phage. To our knowledge, this represents the first detailed description in L. lactis of the molecular mechanisms involved in the host response to the membrane perturbations mediated by phage infection.
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19
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Discovery of nigerose phosphorylase from Clostridium phytofermentans. Appl Microbiol Biotechnol 2011; 93:1513-22. [PMID: 21808968 DOI: 10.1007/s00253-011-3515-9] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Revised: 07/15/2011] [Accepted: 07/24/2011] [Indexed: 10/17/2022]
Abstract
A novel phosphorylase from Clostridium phytofermentans belonging to the glycoside hydrolase family (GH) 65 (Cphy1874) was characterized. The recombinant Cphy1874 protein produced in Escherichia coli showed phosphorolytic activity on nigerose in the presence of inorganic phosphate, resulting in the release of D-glucose and β-D-glucose 1-phosphate (β-G1P) with the inversion of the anomeric configuration. Kinetic parameters of the phosphorolytic activity on nigerose were k(cat) = 67 s(-1) and K(m) = 1.7 mM. This enzyme did not phosphorolyze substrates for the typical GH65 enzymes such as trehalose, maltose, and trehalose 6-phosphate except for a weak phosphorolytic activity on kojibiose. It showed the highest reverse phosphorolytic activity in the reverse reaction using D-glucose as the acceptor and β-G1P as the donor, and the product was mostly nigerose at the early stage of the reaction. The enzyme also showed reverse phosphorolytic activity, in a decreasing order, on D-xylose, 1,5-anhydro-D-glucitol, D-galactose, and methyl-α-D-glucoside. All major products were α-1,3-glucosyl disaccharides, although the reaction with D-xylose and methyl-α-D-glucoside produced significant amounts of α-1,2-glucosides as by-products. We propose 3-α-D-glucosyl-D-glucose:phosphate β-D-glucosyltransferase as the systematic name and nigerose phosphorylase as the short name for this Cphy1874 protein.
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20
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Cao R, Zeidan AA, Rådström P, van Niel EWJ. Inhibition kinetics of catabolic dehydrogenases by elevated moieties of ATP and ADP--implication for a new regulation mechanism in Lactococcus lactis. FEBS J 2010; 277:1843-52. [PMID: 20193044 DOI: 10.1111/j.1742-4658.2010.07601.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
ATP and ADP inhibit, in varying degrees, several dehydrogenases of the central carbon metabolism of Lactococcus lactis ATCC 19435 in vitro, i.e. glyceraldehyde-3-phosphate dehydrogenase (GAPDH), lactate dehydrogenase (LDH) and alcohol dehydrogenase (ADH). Here we demonstrate mixed inhibition for GAPDH and competitive inhibition for LDH and ADH by adenine nucleotides in single inhibition studies. The nonlinear negative co-operativity was best modelled with Hill-type kinetics, showing greater flexibility than the usual parabolic inhibition equation. Because these natural inhibitors are present simultaneously in the cytoplasm, multiple inhibition kinetics was determined for each dehydrogenase. For ADH and LDH, the inhibitor combinations ATP plus NAD and ADP plus NAD are indifferent to each other. Model discrimination suggested that the weak allosteric inhibition of GAPDH had no relevance when multiple inhibitors are present. Interestingly, with ADH and GAPDH the combination of ATP and ADP exhibits lower dissociation constants than with either inhibitor alone. Moreover, the concerted inhibition of ADH and GAPDH, but not of LDH, shows synergy between the two nucleotides. Similar kinetics, but without synergies, were found for horse liver and yeast ADHs, indicating that dehydrogenases can be modulated by these nucleotides in a nonlinear manner in many organisms. The action of an elevated pool of ATP and ADP may effectively inactivate lactococcal ADH, but not GAPDH and LDH, providing leverage for the observed metabolic shift to homolactic acid formation in lactococcal resting cells on maltose. Therefore, we interpret these results as a regulation mechanism contributing to readjusting the flux of ATP production in L. lactis.
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Affiliation(s)
- Rong Cao
- Department of Applied Microbiology, Lund University, Lund, Sweden
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21
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Seibold GM, Wurst M, Eikmanns BJ. Roles of maltodextrin and glycogen phosphorylases in maltose utilization and glycogen metabolism in Corynebacterium glutamicum. MICROBIOLOGY-SGM 2009; 155:347-358. [PMID: 19202084 DOI: 10.1099/mic.0.023614-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Corynebacterium glutamicum transiently accumulates large amounts of glycogen, when cultivated on glucose and other sugars as a source of carbon and energy. Apart from the debranching enzyme GlgX, which is required for the formation of maltodextrins from glycogen, alpha-glucan phosphorylases were assumed to be involved in glycogen degradation, forming alpha-glucose 1-phosphate from glycogen and from maltodextrins. We show here that C. glutamicum in fact possesses two alpha-glucan phosphorylases, which act as a glycogen phosphorylase (GlgP) and as a maltodextrin phosphorylase (MalP). By chromosomal inactivation and subsequent analysis of the mutant, cg1479 was identified as the malP gene. The deletion mutant C. glutamicum DeltamalP completely lacked MalP activity and showed reduced intracellular glycogen degradation, confirming the proposed pathway for glycogen degradation in C. glutamicum via GlgP, GlgX and MalP. Surprisingly, the DeltamalP mutant showed impaired growth, reduced viability and altered cell morphology on maltose and accumulated much higher concentrations of glycogen and maltodextrins than the wild-type during growth on this substrate, suggesting an additional role of MalP in maltose metabolism of C. glutamicum. Further assessment of enzyme activities revealed the presence of 4-alpha-glucanotransferase (MalQ), glucokinase (Glk) and alpha-phosphoglucomutase (alpha-Pgm), and the absence of maltose hydrolase, maltose phosphorylase and beta-Pgm, all three known to be involved in maltose utilization by Gram-positive bacteria. Based on these findings, we conclude that C. glutamicum metabolizes maltose via a pathway involving maltodextrin and glucose formation by MalQ, glucose phosphorylation by Glk and maltodextrin degradation via the reactions of MalP and alpha-Pgm, a pathway hitherto known to be present in Gram-negative rather than in Gram-positive bacteria.
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Affiliation(s)
- Gerd M Seibold
- Institute of Biochemistry, University of Cologne, D-50674 Cologne, Germany.,Institute of Microbiology and Biotechnology, University of Ulm, D-89069 Ulm, Germany
| | - Martin Wurst
- Institute of Microbiology and Biotechnology, University of Ulm, D-89069 Ulm, Germany
| | - Bernhard J Eikmanns
- Institute of Microbiology and Biotechnology, University of Ulm, D-89069 Ulm, Germany
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22
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Van der Meulen R, Grosu-Tudor S, Mozzi F, Vaningelgem F, Zamfir M, de Valdez GF, De Vuyst L. Screening of lactic acid bacteria isolates from dairy and cereal products for exopolysaccharide production and genes involved. Int J Food Microbiol 2007; 118:250-8. [PMID: 17716765 DOI: 10.1016/j.ijfoodmicro.2007.07.014] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2006] [Revised: 05/04/2007] [Accepted: 07/22/2007] [Indexed: 11/16/2022]
Abstract
A total of 174 lactic acid bacteria (LAB) strains isolated from dairy and cereal products were screened for the production of exopolysaccharides (EPS). Therefore, a rapid screening method was developed based on ultrafiltration and gel permeation chromatography. Furthermore, a screening through the polymerase chain reaction (PCR) was performed with primer pairs targeting different genes involved in EPS production. Nine isolates produced a homopolysaccharide of the glucan type, whereas only one strain produced a heteropolysaccharide. The production of a glucan by a strain of Lactococcus lactis and the production of a heteropolysaccharide by a strain of Lactobacillus curvatus are reported for the first time. The PCR screening revealed many positive strains. For three of the ten EPS-producing strains, no corresponding genes could be detected. Furthermore, a lot of strains possessed one or more eps genes but did not produce an EPS. Therefore, a screening on the molecular level should always be accompanied by another screening method that is able to distinguish true EPS producer strains from non-producing ones. Statistical analysis did not reveal any relationship between the type and origin of the strains, the presence or absence of a capsular polysaccharide or EPS, and the presence or absence of eps genes.
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Affiliation(s)
- Roel Van der Meulen
- Research Group of Industrial Microbiology and Food Biotechnology (IMDO), Department of Applied Biological Sciences and Engineering, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
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23
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Neves AR, Pool WA, Castro R, Mingote A, Santos F, Kok J, Kuipers OP, Santos H. The α-Phosphoglucomutase of Lactococcus lactis Is Unrelated to the α-d-Phosphohexomutase Superfamily and Is Encoded by the Essential Gene pgmH. J Biol Chem 2006; 281:36864-73. [PMID: 16980299 DOI: 10.1074/jbc.m607044200] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
alpha-Phosphoglucomutase (alpha-PGM) plays an important role in carbohydrate metabolism by catalyzing the reversible conversion of alpha-glucose 1-phosphate to glucose 6-phosphate. Isolation of alpha-PGM activity from cell extracts of Lactococcus lactis strain MG1363 led to the conclusion that this activity is encoded by yfgH, herein renamed pgmH. Its gene product has no sequence homology to proteins in the alpha-d-phosphohexomutase superfamily and is instead related to the eukaryotic phosphomannomutases within the haloacid dehalogenase superfamily. In contrast to known bacterial alpha-PGMs, this 28-kDa enzyme is highly specific for alpha-glucose 1-phosphate and glucose 6-phosphate and showed no activity for mannose phosphate. To elucidate the function of pgmH, the metabolism of glucose and galactose was characterized in mutants overproducing or with a deficiency of alpha-PGM activity. Overproduction of alpha-PGM led to increased glycolytic flux and growth rate on galactose. Despite several attempts, we failed to obtain a deletion mutant of pgmH. The essentiality of this gene was proven by using a conditional knock-out strain in which a native copy of the gene was provided in trans under the control of the nisin promoter. Growth of this strain was severely impaired when alpha-PGM activity was below the control level. We show that the novel L. lactis alpha-PGM is the only enzyme that mediates the interconversion of alpha-glucose 1-phosphate to glucose 6-phosphate and is essential for growth.
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Affiliation(s)
- Ana R Neves
- Instituto de Tecnologia Química e Biológica and Instituto de Biologia Experimental e Tecnológica, Universidade Nova de Lisboa, Rua da Quinta Grande, 6, Apartado 127, 2780-156 Oeiras, Portugal
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24
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Buchanan JT, Stannard JA, Lauth X, Ostland VE, Powell HC, Westerman ME, Nizet V. Streptococcus iniae phosphoglucomutase is a virulence factor and a target for vaccine development. Infect Immun 2005; 73:6935-44. [PMID: 16177373 PMCID: PMC1230984 DOI: 10.1128/iai.73.10.6935-6944.2005] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Streptococcus iniae represents a major health and economic problem in fish species worldwide. Random Tn917 mutagenesis and high-throughput screening in a hybrid striped bass (HSB) model of meningoencephalitis identified attenuated S. iniae mutants. The Tn917 insertion in one mutant disrupted an S. iniae homologue of a phosphoglucomutase (pgm) gene. Electron microscopy revealed a decrease in capsule thickness and cell wall rigidity, with DeltaPGM mutant cells reaching sizes approximately 3-fold larger than those of the wild type (WT). The DeltaPGM mutant was cleared more rapidly in HSB blood and was more sensitive to killing by cationic antimicrobial peptides including moronecidin from HSB. In vivo, the DeltaPGM mutant was severely attenuated in HSB, as intraperitoneal challenge with 1,000 times the WT lethal dose produced only 2.5% mortality. Reintroduction of an intact copy of the S. iniae pgm gene on a plasmid vector restored antimicrobial peptide resistance and virulence to the DeltaPGM mutant. In analysis of the aborted infectious process, we found that DeltaPGM mutant organisms initially disseminated to the blood, brain, and spleen but were eliminated by 24 h without end organ damage. Ninety to 100% of fish injected with the DeltaPGM mutant and later challenged with a lethal dose of WT S. iniae survived. We conclude that the pgm gene is required for virulence in S. iniae, playing a role in normal cell wall morphology, surface capsule expression, and resistance to innate immune clearance mechanisms. An S. iniae DeltaPGM mutant is able to stimulate a protective immune response and may have value as a live attenuated vaccine for aquaculture.
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Affiliation(s)
- John T Buchanan
- Department of Pediatrics, University of California, San Diego, School of Medicine, La Jolla, 92093, USA.
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25
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Le Breton Y, Pichereau V, Sauvageot N, Auffray Y, Rincé A. Maltose utilization in Enterococcus faecalis. J Appl Microbiol 2005; 98:806-13. [PMID: 15752325 DOI: 10.1111/j.1365-2672.2004.02468.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
AIMS The aim of this research was to characterize the metabolic pathway for maltose utilization in Enterococcus faecalis. METHODS AND RESULTS Screening a library of Enterococcus faecalis insertional mutants allowed the isolation of mutants affected in maltose utilization. Genetic analysis of the insertion loci revealed insertions in neighbour genes encoding an EII component of a phosphotransferase system (PTS) transporter (malT) and a maltose phosphorylase homologue (malP). The malP gene forms part of an operon which also includes genes encoding a phosphoglucomutase (malB), a mutarotase (aldose 1-epimerase) (malM) and a transcriptional regulator (malR). Analysis of (14)C-labelled carbohydrates uptake revealed that more than 97% of maltose enters the cells by the PTS transporter MalT. CONCLUSIONS Both experimental data and genetic organization of the malPBMR operon strongly suggest that in Enterococcus faecalis, maltose enters using a PTS, leaving maltose-6-phosphate inside the cells which is hydrolysed by a maltose phosphate phosphorylase (MalP). SIGNIFICANCE AND IMPACT OF THE STUDY This study describes a new pathway for maltose utilization in lactic acid bacteria.
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Affiliation(s)
- Y Le Breton
- Laboratoire de Microbiologie de l'Environnement, USC INRA, IRBA, Université de Caen, 14032 Caen Cedex, France
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26
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Andersson U, Molenaar D, Rådström P, de Vos WM. Unity in organisation and regulation of catabolic operons in Lactobacillus plantarum, Lactococcus lactis and Listeria monocytogenes. Syst Appl Microbiol 2005; 28:187-95. [PMID: 15900965 DOI: 10.1016/j.syapm.2004.11.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Global regulatory circuits together with more specific local regulators play a notable role when cells are adapting to environmental changes. Lactococcus lactis is a lactic acid bacterium abundant in nature fermenting most mono- and disaccharides. Comparative genomics analysis of the operons encoding the proteins and enzymes crucial for catabolism of lactose, maltose and threhalose revealed an obvious unity in operon organisation . The local regulator of each operon was located in a divergent transcriptional direction to the rest of the operon including the transport protein-encoding genes. Furthermore, in all three operons a catabolite responsive element (CRE) site was detected inbetween the gene encoding the local regulator and one of the genes encoding a sugar transport protein. It is evident that regardless of type of transport system and catabolic enzymes acting upon lactose, maltose and trehalose, respectively, Lc. lactis shows unity in both operon organisation and regulation of these catabolic operons. This knowledge was further extended to other catabolic operons in Lc. lactis and the two related bacteria Lactobacillus plantarum and Listeria monocytogenes. Thirty-nine catabolic operons responsible for degradation of sugars and sugar alcohols in Lc. lactis, Lb. plantarum and L. monocytogenes were investigated and the majority of those possessed the same organisation as the lactose, maltose and trehalose operons of Lc. lactis. Though, the frequency of CRE sites and their location varied among the bacteria. Both Lc. lactis and Lb. plantarum showed CRE sites in direct proximity to genes coding for proteins responsible for sugar uptake. However, in L. monocytogenes CRE sites were not frequently found and not in the vicinity of genes encoding transport proteins, suggesting a more local mode of regulation of the catabolic operons found and/or the use of inducer control in this bacterium.
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Affiliation(s)
- Ulrika Andersson
- Applied Microbiology, Lund Institute of Technology, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden.
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Neves AR, Pool WA, Kok J, Kuipers OP, Santos H. Overview on sugar metabolism and its control inLactococcus lactis— The input from in vivo NMR. FEMS Microbiol Rev 2005. [DOI: 10.1016/j.fmrre.2005.04.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Jensen JB, Ampomah OY, Darrah R, Peters NK, Bhuvaneswari TV. Role of trehalose transport and utilization in Sinorhizobium meliloti--alfalfa interactions. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2005; 18:694-702. [PMID: 16042015 DOI: 10.1094/mpmi-18-0694] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Genes thuA and thuB in Sinorhizobium meliloti Rm1021 code for a major pathway for trehalose catabolism and are induced by trehalose but not by related structurally similar disaccharides like sucrose or maltose. S. meliloti strains mutated in either of these two genes were severely impaired in their ability to grow on trehalose as the sole source of carbon. ThuA and ThuB show no homology to any known enzymes in trehalose utilization. ThuA has similarity to proteins of unknown function in Mesorhizobium loti, Agrobacterium tumefaciens, and Brucella melitensis, and ThuB possesses homology to dehydrogenases containing the consensus motif AGKHVXCEKP. thuAB genes are expressed in bacteria growing on the root surface and in the infection threads but not in the symbiotic zone of the nodules. Even though thuA and thuB mutants were impaired in competitive colonization of Medicago sativa roots, these strains were more competitive than the wild-type Rml021 in infecting alfalfa roots and forming nitrogen-fixing nodules. Possible reasons for their increased competitiveness are discussed.
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Affiliation(s)
- John Beck Jensen
- Department of Biology, Faculty of Science, University of Tromsø, N-9037 Tromsø, Norway
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Palmfeldt J, Paese M, Hahn-Hägerdal B, Van Niel EWJ. The pool of ADP and ATP regulates anaerobic product formation in resting cells of Lactococcus lactis. Appl Environ Microbiol 2004; 70:5477-84. [PMID: 15345435 PMCID: PMC520924 DOI: 10.1128/aem.70.9.5477-5484.2004] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Lactococcus lactis grows homofermentatively on glucose, while its growth on maltose under anaerobic conditions results in mixed acid product formation in which formate, acetate, and ethanol are formed in addition to lactate. Maltose was used as a carbon source to study mixed acid product formation as a function of the growth rate. In batch and nitrogen-limited chemostat cultures mixed acid product formation was shown to be linked to the growth rate, and homolactic fermentation occurred only in resting cells. Two of the four lactococcal strains investigated with maltose, L. lactis 65.1 and MG1363, showed more pronounced mixed acid product formation during growth than L. lactis ATCC 19435 or IL-1403. In resting cell experiments all four strains exhibited homolactic fermentation. In resting cells the intracellular concentrations of ADP, ATP, and fructose 1,6-bisphosphate were increased and the concentration of P(i) was decreased compared with the concentrations in growing cells. Addition of an ionophore (monensin or valinomycin) to resting cultures of L. lactis 65.1 induced mixed acid product formation concomitant with decreases in the ADP, ATP, and fructose 1,6-bisphosphate concentrations. ADP and ATP were shown to inhibit glyceraldehyde-3-phosphate dehydrogenase, lactate dehydrogenase, and alcohol dehydrogenase in vitro. Alcohol dehydrogenase was the most sensitive enzyme and was totally inhibited at an adenine nucleotide concentration of 16 mM, which is close to the sum of the intracellular concentrations of ADP and ATP of resting cells. This inhibition of alcohol dehydrogenase might be partially responsible for the homolactic behavior of resting cells. A hypothesis regarding the level of the ATP-ADP pool as a regulating mechanism for the glycolytic flux and product formation in L. lactis is discussed.
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Affiliation(s)
- Johan Palmfeldt
- Applied Microbiology, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden.
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Palmfeldt J, Levander F, Hahn-Hägerdal B, James P. Acidic proteome of growing and restingLactococcus lactismetabolizing maltose. Proteomics 2004; 4:3881-98. [PMID: 15540167 DOI: 10.1002/pmic.200400858] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The acidic proteome of Lactococcus lactis grown anaerobically was compared for three different growth conditions: cells growing on maltose, resting cells metabolizing maltose, and cells growing on glucose. In maltose metabolizing cells several proteins were up-regulated compared with glucose metabolizing cells, however only some of the up-regulated proteins had apparent relation to maltose metabolism. Cells growing on maltose produced formate, acetate and ethanol in addition to lactate, whereas resting cells metabolizing maltose and cells growing on glucose produced only lactate. Increased levels of alcohol-acetaldehyde dehydrogenase (ADH) and phosphate acetyltransferase (PTA) in maltose-growing cells compared with glucose-growing cells coincided with formation of mixed acids in maltose-growing cells. The resting cells did not grow due to lack of an amino acid source and fermented maltose with lactate as the sole product, although ADH and PTA were present at high levels. The maltose consumption rate was approximately three times lower in resting cells than in exponentially growing cells. However, the enzyme levels in resting and growing cells metabolizing maltose were similar, which indicates that the difference in product formation in this case is due to regulation at the enzyme level. The levels of 30S ribosomal proteins S1 and S2 increased with increasing growth rate for resting cells metabolizing maltose, maltose-growing cells and glucose-growing cells. A modified form of HPr was synthesized under amino acid starvation. This is suggested to be due to alanine misincorporation for valine, which L. lactis is auxotrophic for. L. lactis conserves the protein profile to a high extent, even after prolonged amino acid starvation, so that the protein expression profile of the bacterium remains almost invariant.
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Andersson U, Rådström P. Physiological function of the maltose operon regulator, MalR, in Lactococcus lactis. BMC Microbiol 2002; 2:28. [PMID: 12296976 PMCID: PMC130022 DOI: 10.1186/1471-2180-2-28] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2002] [Accepted: 09/25/2002] [Indexed: 11/27/2022] Open
Abstract
Background Maltose metabolism is initiated by an ATP-dependent permease system in Lactococcus lactis. The subsequent degradation of intracellular maltose is performed by the concerted action of Pi-dependent maltose phosphorylase and β-phosphoglucomutase. In some Gram-positive bacteria, maltose metabolism is regulated by a maltose operon regulator (MalR), belonging to the LacI-GalR family of transcriptional regulators. A gene presumed to encode MalR has been found directly downstream the maltose phosphorylase-encoding gene, malP in L. lactis. The purpose of this study was to investigate the physiological role of the MalR protein in maltose metabolism in L. lactis. Results A L. lactis ssp. lactis mutant, TMB5004, deficient in the putative MalR protein, was physiologically characterised. The mutant was not able to ferment maltose, while its capability to grow on glucose as well as trehalose was not affected. The activity of maltose phosphorylase and β-phosphoglucomutase was not affected in the mutant. However, the specific maltose uptake rate in the wild type was, at its lowest, five times higher than in the mutant. This difference in maltose uptake increased as the maltose concentration in the assay was increased. Conclusion According to amino acid sequence similarities, the presumed MalR is a member of the LacI-GalR family of transcriptional regulators. Due to the suggested activating effect on maltose transport and absence of effect on the activities of maltose phosphorylase and β-phosphoglucomutase, MalR of L. lactis is considered rather as an activator than a repressor.
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Affiliation(s)
- Ulrika Andersson
- Applied Microbiology, Center for Chemistry and Chemical Engineering, Lund Institute of Technology, Lund University, P. O. Box 124, SE-221 00 Lund, Sweden
| | - Peter Rådström
- Applied Microbiology, Center for Chemistry and Chemical Engineering, Lund Institute of Technology, Lund University, P. O. Box 124, SE-221 00 Lund, Sweden
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Andersson U, Rådström P. Beta-glucose 1-phosphate-interconverting enzymes in maltose- and trehalose-fermenting lactic acid bacteria. Environ Microbiol 2002; 4:81-8. [PMID: 11972617 DOI: 10.1046/j.1462-2920.2002.00268.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Maltose and trehalose catabolic pathways are linked through their common enzyme, beta-phosphoglucomutase, and metabolite, beta-glucose 1-phosphate, in Lactococcus lactis. Maltose is degraded by the concerted action of maltose phosphorylase and beta-phosphoglucomutase, whereas trehalose is assimilated by a novel pathway, including the recently discovered enzyme, trehalose 6-phosphate phosphorylase, and beta-phosphoglucomutase. In the present study, 40 strains of lactic acid bacteria were investigated for utilization of metabolic reactions involving beta-glucose 1-phosphate. All genera of the low G+C content lactic acid bacteria belonging to the clostridial subbranch of Gram-positive bacteria were represented in the study. The strains, which fermented maltose or trehalose, were investigated for beta-phosphoglucomutase, maltose phosphorylase and trehalose 6-phosphate phosphorylase activity, as indications of maltose and trehalose catabolic pathways involving beta-glucose 1-phosphate interconversions. Eighty per cent of all strains fermented maltose and, of these strains, 63% were shown to use a maltose phosphorylase/beta- phosphoglucomutase pathway. One-third of the strains fermenting trehalose were found to harbour trehalose 6-phosphate phosphorylase activity, and these were also shown to possess beta-phosphoglucomutase activity. Mainly L. lactis and Enterococcus faecalis strains were found to harbour the novel trehalose 6-phosphate phosphorylase/beta-phosphoglucomutase pathway. As lower beta-glucose 1-phosphate interconverting enzyme activities were observed in the majority of glucose-cultivated lactic acid bacteria, glucose was suggested to repress the synthesis of these enzymes in most strains. Thus, metabolic reactions involving the beta-anomer of glucose 1-phosphate are frequently found in both maltose- and trehalose-utilizing lactic acid bacteria.
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Affiliation(s)
- Ulrika Andersson
- Applied Microbiology, Center for Chemistry and Chemical Engineering, Lund Institute of Technology, Lund University, PO Box 124, SE-221 00 Lund, Sweden
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Andersson U, Levander F, Rådström P. Trehalose-6-phosphate phosphorylase is part of a novel metabolic pathway for trehalose utilization in Lactococcus lactis. J Biol Chem 2001; 276:42707-13. [PMID: 11553642 DOI: 10.1074/jbc.m108279200] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Lactococcus lactis splits phosphorylated trehalose by the action of inorganic phosphate-dependent trehalose-6-phosphate phosphorylase (TrePP) in a novel catabolic pathway. TrePP was found to catalyze the reversible conversion of trehalose 6-phosphate into beta-glucose 1-phosphate and glucose 6-phosphate by measuring intermediate sugar phosphates in cell extracts from trehalose-cultivated lactococci. According to native PAGE and SDS-PAGE, TrePP was shown to be a monomeric enzyme with a molecular mass of 94 kDa. Reaction kinetics suggested that the enzyme follows a ternary complex mechanism with optimal phosphorolysis at 35 degrees C and pH 6.3. The equilibrium constants were found to be 0.026 and 0.032 at pH 6.3 and 7.0, respectively, favoring the formation of trehalose 6-phosphate. The Michaelis-Menten constants of TrePP for trehalose 6-phosphate, inorganic phosphate, beta-glucose 1-phosphate, and glucose 6-phosphate were determined to be 6, 32, 0.9, and 4 mm, respectively. The TrePP-encoding gene, designated trePP, was localized in a putative trehalose operon of L. lactis. This operon includes the gene encoding beta-phosphoglucomutase in addition to three open reading frames believed to encode a transcriptional regulator and two trehalose-specific phosphotransferase system components. The identity of trePP was confirmed by determining the N-terminal amino acid sequence of TrePP and by its overexpression in Escherichia coli and L. lactis, as well as the construction of a lactococcal trePP knockout mutant. Furthermore, both TrePP and beta-phosphoglucomutase activity were detected in Enterococcus faecalis cell extract, indicating that this bacterium exhibits the same trehalose assimilation route as L. lactis.
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Affiliation(s)
- U Andersson
- Applied Microbiology, Center for Chemistry and Chemical Engineering, Lund Institute of Technology, Lund University, P.O. Box 124, Lund SE-221 00, Sweden
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