1
|
De Doncker M, Vleminckx S, Franceus J, Vercauteren R, Desmet T. Converting Bulk Sugars into Functional Fibers: Discovery and Application of a Thermostable β-1,3-Oligoglucan Phosphorylase. J Agric Food Chem 2024; 72:10497-10505. [PMID: 38659290 DOI: 10.1021/acs.jafc.4c01990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
Despite their broad application potential, the widespread use of β-1,3-glucans has been hampered by the high cost and heterogeneity associated with current production methods. To address this challenge, scalable and economically viable processes are needed for the production of β-1,3-glucans with tailorable molecular mass distributions. Glycoside phosphorylases have shown to be promising catalysts for the bottom-up synthesis of β-1,3-(oligo)glucans since they combine strict regioselectivity with a cheap donor substrate (i.e., α-glucose 1-phosphate). However, the need for an expensive priming substrate (e.g., laminaribiose) and the tendency to produce shorter oligosaccharides still form major bottlenecks. Here, we report the discovery and application of a thermostable β-1,3-oligoglucan phosphorylase originating from Anaerolinea thermophila (AtβOGP). This enzyme combines a superior catalytic efficiency toward glucose as a priming substrate, high thermostability, and the ability to synthesize high molecular mass β-1,3-glucans up to DP 75. Coupling of AtβOGP with a thermostable variant of Bifidobacterium adolescentis sucrose phosphorylase enabled the efficient production of tailorable β-1,3-(oligo)glucans from sucrose, with a near-complete conversion of >99 mol %. This cost-efficient process for the conversion of renewable bulk sugar into β-1,3-(oligo)glucans should facilitate the widespread application of these versatile functional fibers across various industries.
Collapse
Affiliation(s)
- Marc De Doncker
- Department of Biotechnology, Centre for Synthetic Biology (CSB), Ghent University, Coupure Links 653, B-9000 Ghent, Belgium
| | - Sofie Vleminckx
- Department of Biotechnology, Centre for Synthetic Biology (CSB), Ghent University, Coupure Links 653, B-9000 Ghent, Belgium
| | - Jorick Franceus
- Department of Biotechnology, Centre for Synthetic Biology (CSB), Ghent University, Coupure Links 653, B-9000 Ghent, Belgium
| | - Ronny Vercauteren
- Cargill R&D Centre Europe BV, Havenstraat 84, B-1800 Vilvoorde, Belgium
| | - Tom Desmet
- Department of Biotechnology, Centre for Synthetic Biology (CSB), Ghent University, Coupure Links 653, B-9000 Ghent, Belgium
| |
Collapse
|
2
|
Li Y, Zhang W, Zhang D, Zheng Y, Xu Y, Liu B, Li Q. Mechanism of [CO(2)] Enrichment Alleviated Drought Stress in the Roots of Cucumber Seedlings Revealed via Proteomic and Biochemical Analysis. Int J Mol Sci 2022; 23. [PMID: 36499239 DOI: 10.3390/ijms232314911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 11/25/2022] [Accepted: 11/25/2022] [Indexed: 11/30/2022] Open
Abstract
Cucumber is one of the most widely cultivated greenhouse vegetables, and its quality and yield are threatened by drought stress. Studies have shown that carbon dioxide concentration ([CO2]) enrichment can alleviate drought stress in cucumber seedlings; however the mechanism of this [CO2] enrichment effect on root drought stress is not clear. In this study, the effects of different drought stresses (simulated with 0, 5% and 10% PEG 6000, i.e., no, moderate, and severe drought stress) and [CO2] (400 μmol·mol-1 and 800 ± 40 μmol·mol-1) on the cucumber seedling root proteome were analyzed using the tandem mass tag (TMT) quantitative proteomics method. The results showed that after [CO2] enrichment, 346 differentially accumulating proteins (DAPs) were found only under moderate drought stress, 27 DAPs only under severe drought stress, and 34 DAPs under both moderate and severe drought stress. [CO2] enrichment promoted energy metabolism, amino acid metabolism, and secondary metabolism, induced the expression of proteins related to root cell wall and cytoskeleton metabolism, effectively maintained the balance of protein processing and degradation, and enhanced the cell wall regulation ability. However, the extent to which [CO2] enrichment alleviated drought stress in cucumber seedling roots was limited under severe drought stress, which may be due to excessive damage to the seedlings.
Collapse
|
3
|
Wang Z, Enotarpi J, Buffi G, Pezzicoli A, Gstöttner CJ, Nicolardi S, Balducci E, Fabbrini M, Romano MR, van der Marel GA, del Bino L, Adamo R, Codée JDC. Chemical Synthesis and Immunological Evaluation of Fragments of the Multiantennary Group-Specific Polysaccharide of Group B Streptococcus. JACS Au 2022; 2:1724-1735. [PMID: 35911445 PMCID: PMC9327088 DOI: 10.1021/jacsau.2c00302] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Group B Streptococcus (GBS) is a Gram-positive bacterium and the most common cause of neonatal blood and brain infections. At least 10 different serotypes exist, that are characterized by their different capsular polysaccharides. The Group B carbohydrate (GBC) is shared by all serotypes and therefore attractive be used in a glycoconjugate vaccine. The GBC is a highly complex multiantennary structure, composed of rhamnose rich oligosaccharides interspaced with glucitol phosphates. We here report the development of a convergent approach to assemble a pentamer, octamer, and tridecamer fragment of the termini of the antennae. Phosphoramidite chemistry was used to fuse the pentamer and octamer fragments to deliver the 13-mer GBC oligosaccharide. Nuclear magnetic resonance spectroscopy of the generated fragments confirmed the structures of the naturally occurring polysaccharide. The fragments were used to generate model glycoconjugate vaccine by coupling with CRM197. Immunization of mice delivered sera that was shown to be capable of recognizing different GBS strains. The antibodies raised using the 13-mer conjugate were shown to recognize the bacteria best and the serum raised against this GBC fragment-mediated opsonophagocytic killing best, but in a capsule dependent manner. Overall, the GBC 13-mer was identified to be a highly promising antigen for incorporation into future (multicomponent) anti-GBS vaccines.
Collapse
Affiliation(s)
- Zhen Wang
- Leiden
Institute of Chemistry, Leiden University, Einsteinweg 55, 2333 CC Leiden, The Netherlands
| | - Jacopo Enotarpi
- Leiden
Institute of Chemistry, Leiden University, Einsteinweg 55, 2333 CC Leiden, The Netherlands
| | - Giada Buffi
- GSK
Siena Italy, Via Fiorentina
1 Siena 53100, Italy
| | | | - Christoph J. Gstöttner
- Center
for Proteomics and Metabolomics, Leiden
University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | - Simone Nicolardi
- Center
for Proteomics and Metabolomics, Leiden
University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| | | | | | | | | | | | - Roberto Adamo
- GSK
Siena Italy, Via Fiorentina
1 Siena 53100, Italy
| | - Jeroen D. C. Codée
- Leiden
Institute of Chemistry, Leiden University, Einsteinweg 55, 2333 CC Leiden, The Netherlands
| |
Collapse
|
4
|
Rapp C, van Overtveldt S, Beerens K, Weber H, Desmet T, Nidetzky B. Expanding the Enzyme Repertoire for Sugar Nucleotide Epimerization: The CDP-Tyvelose 2-Epimerase from Thermodesulfatator atlanticus for Glucose/Mannose Interconversion. Appl Environ Microbiol 2021; 87:AEM. [PMID: 33277270 DOI: 10.1128/AEM.02131-20] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
Abstract
Epimerization of sugar nucleotides is central to the structural diversification of monosaccharide building blocks for cellular biosynthesis. Epimerase applicability to carbohydrate synthesis can be limited, however, by the high degree of substrate specificity exhibited by most sugar nucleotide epimerases. Here, we discovered a promiscuous type of CDP-tyvelose 2-epimerase (TyvE)-like enzyme that promotes C2-epimerization in all nucleotide (CDP, UDP, GDP, ADP, TDP)-activated forms of d-glucose. This new epimerase, originating from Thermodesulfatator atlanticus, is a functional homodimer that contains one tightly bound NAD+/subunit and shows optimum activity at 70°C and pH 9.5. The enzyme exhibits a k cat with CDP-dglucose of ∼1.0 min-1 (pH 7.5, 60°C). To characterize the epimerase kinetically and probe its substrate specificity, we developed chemo-enzymatic syntheses for CDP-dmannose, CDP-6-deoxy-dglucose, CDP-3-deoxy-dglucose and CDP-6-deoxy-dxylo-hexopyranos-4-ulose. Attempts to obtain CDP-dparatose and CDP-dtyvelose were not successful. Using high-resolution carbohydrate analytics and in situ NMR to monitor the enzymatic conversions (60°C, pH 7.5), we show that the CDP-dmannose/CDP-dglucose ratio at equilibrium is 0.67 (± 0.1), determined from the kinetic Haldane relationship and directly from the reaction. We further show that deoxygenation at sugar C6 enhances the enzyme activity 5-fold compared to CDP-dglucose whereas deoxygenation at C3 renders the substrate inactive. Phylogenetic analysis places the T. atlanticus epimerase into a distinct subgroup within the sugar nucleotide epimerase family of SDR (short-chain dehydrogenases/reductases), for which the current study now provides the functional context. Collectively, our results expand an emerging toolbox of epimerase-catalyzed reactions for sugar nucleotide synthesis.IMPORTANCE Epimerases of the sugar nucleotide-modifying class of enzymes have attracted considerable interest in carbohydrate (bio)chemistry, for the mechanistic challenges and the opportunities for synthesis involved in the reactions catalyzed. Discovery of new epimerases with expanded scope of sugar nucleotide substrates used is important to promote the mechanistic inquiry and can facilitate the development of new enzyme applications. Here, a CDP-tyvelose 2-epimerase-like enzyme from Thermodesulfatator atlanticus is shown to catalyze sugar C2 epimerization in CDP-glucose and other nucleotide-activated forms of dglucose. The reactions are new to nature in the context of enzymatic sugar nucleotide modification. The current study explores the substrate scope of the discovered C2-epimerase and, based on modeling, suggests structure-function relationships that may be important for specificity and catalysis.
Collapse
|
5
|
Hosseini SA, Réthoré E, Pluchon S, Ali N, Billiot B, Yvin JC. Calcium Application Enhances Drought Stress Tolerance in Sugar Beet and Promotes Plant Biomass and Beetroot Sucrose Concentration. Int J Mol Sci 2019; 20:E3777. [PMID: 31382384 DOI: 10.3390/ijms20153777] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 07/29/2019] [Accepted: 07/31/2019] [Indexed: 12/26/2022] Open
Abstract
Numerous studies have demonstrated the potential of sugar beet to lose the final sugar yield under water limiting regime. Ample evidences have revealed the important role of mineral nutrition in increasing plant tolerance to abiotic stresses. Despite the vital role of calcium (Ca2+) in plant growth and development, as well as in stress responses as an intracellular messenger, its role in alleviating drought stress in sugar beet has been rarely addressed. Here, an attempt was undertaken to investigate whether, and to what extent, foliar application of Ca2+ confers drought stress tolerance in sugar beet plants exposed to drought stress. To achieve this goal, sugar beet plants, which were grown in a high throughput phenotyping platform, were sprayed with Ca2+ and submitted to drought stress. The results showed that foliar application of Ca2+ increased the level of magnesium and silicon in the leaves, promoted plant growth, height, and leaf coverage area as well as chlorophyll level. Ca2+, in turn, increased the carbohydrate levels in leaves under drought condition and regulated transcriptionally the genes involved in sucrose transport (BvSUC3 and BvTST3). Subsequently, Ca2+ enhanced the root biomass and simultaneously led to induction of root (BvSUC3 and BvTST1) sucrose transporters which eventually supported the loading of more sucrose into beetroot under drought stress. Metabolite analysis revealed that the beneficial effect of Ca2+ in tolerance to drought induced-oxidative stress is most likely mediated by higher glutathione pools, increased levels of free polyamine putrescine (Put), and lower levels of amino acid gamma-aminobutyric acid (GABA). Taken together, this work demonstrates that foliar application of Ca2+ is a promising fertilization strategy to improve mineral nutrition efficiency, sugar metabolism, redox state, and thus, drought stress tolerance.
Collapse
|
6
|
Benkoulouche M, Fauré R, Remaud-Siméon M, Moulis C, André I. Harnessing glycoenzyme engineering for synthesis of bioactive oligosaccharides. Interface Focus 2019; 9:20180069. [PMID: 30842872 DOI: 10.1098/rsfs.2018.0069] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/20/2018] [Indexed: 12/13/2022] Open
Abstract
Combined with chemical synthesis, the use of glycoenzyme biocatalysts has shown great synthetic potential over recent decades owing to their remarkable versatility in terms of substrates and regio- and stereoselectivity that allow structurally controlled synthesis of carbohydrates and glycoconjugates. Nonetheless, the lack of appropriate enzymatic tools with requisite properties in the natural diversity has hampered extensive exploration of enzyme-based synthetic routes to access relevant bioactive oligosaccharides, such as cell-surface glycans or prebiotics. With the remarkable progress in enzyme engineering, it has become possible to improve catalytic efficiency and physico-chemical properties of enzymes but also considerably extend the repertoire of accessible catalytic reactions and tailor novel substrate specificities. In this review, we intend to give a brief overview of the advantageous use of engineered glycoenzymes, sometimes in combination with chemical steps, for the synthesis of natural bioactive oligosaccharides or their precursors. The focus will be on examples resulting from the three main classes of glycoenzymes specialized in carbohydrate synthesis: glycosyltransferases, glycoside hydrolases and glycoside phosphorylases.
Collapse
Affiliation(s)
- Mounir Benkoulouche
- Laboratoire d'Ingénierie des Systèmes Biologiques et Procédés, LISBP, Université de Toulouse, CNRS, INRA, INSA, 135, avenue de Rangueil, 31077 Toulouse cedex 04, France
| | - Régis Fauré
- Laboratoire d'Ingénierie des Systèmes Biologiques et Procédés, LISBP, Université de Toulouse, CNRS, INRA, INSA, 135, avenue de Rangueil, 31077 Toulouse cedex 04, France
| | - Magali Remaud-Siméon
- Laboratoire d'Ingénierie des Systèmes Biologiques et Procédés, LISBP, Université de Toulouse, CNRS, INRA, INSA, 135, avenue de Rangueil, 31077 Toulouse cedex 04, France
| | - Claire Moulis
- Laboratoire d'Ingénierie des Systèmes Biologiques et Procédés, LISBP, Université de Toulouse, CNRS, INRA, INSA, 135, avenue de Rangueil, 31077 Toulouse cedex 04, France
| | - Isabelle André
- Laboratoire d'Ingénierie des Systèmes Biologiques et Procédés, LISBP, Université de Toulouse, CNRS, INRA, INSA, 135, avenue de Rangueil, 31077 Toulouse cedex 04, France
| |
Collapse
|
7
|
Feng X, Yang S, Tang K, Zhang Y, Leng J, Ma J, Wang Q, Feng X. GmPGL1, a Thiamine Thiazole Synthase, Is Required for the Biosynthesis of Thiamine in Soybean. Front Plant Sci 2019; 10:1546. [PMID: 31824549 PMCID: PMC6883718 DOI: 10.3389/fpls.2019.01546] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 11/05/2019] [Indexed: 05/21/2023]
Abstract
Thiamine is an essential cofactor in several enzymatic reactions for all living organisms. Animals cannot synthesize thiamine and depend on their diet. Enhancing the content of thiamine is one of the most important goals of plant breeding to solve the thiamine deficiency associated with the low-thiamin staple crops. In this study, a Glycine max pale green leaf 1 (Gmpgl1) mutant was isolated from the EMS mutagenized population of soybean cultivar, Williams 82. Map-based cloning of the GmPGL1 locus revealed a single nucleotide deletion at the 292th nucleotide residue of the first exon of Glyma.10g251500 gene in Gmpgl1 mutant plant, encoding a thiamine thiazole synthase. Total thiamine contents decreased in both seedlings and seeds of the Gmpgl1 mutant. Exogenous application of thiazole restored the pale green leaf phenotype of the mutant. The deficiency of thiamine in Gmpgl1 mutant led to reduced activities of the pyruvate dehydrogenase (PDH) and pyruvate decarboxylase (PDC), and decreased contents of six amino acids as compared to that in the wild type plants. These results revealed that GmPGL1 played an essential role in thiamine thiazole biosynthesis.
Collapse
Affiliation(s)
- Xingxing Feng
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of eography and Agroecology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Changchun, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Suxin Yang
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of eography and Agroecology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Changchun, China
- *Correspondence: Suxin Yang,
| | - Kuanqiang Tang
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of eography and Agroecology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Changchun, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Yaohua Zhang
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of eography and Agroecology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Changchun, China
| | - Jiantian Leng
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of eography and Agroecology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Changchun, China
| | - Jingjing Ma
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of eography and Agroecology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Changchun, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Quan Wang
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of eography and Agroecology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Changchun, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Xianzhong Feng
- Key Laboratory of Soybean Molecular Design Breeding, Northeast Institute of eography and Agroecology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Changchun, China
| |
Collapse
|
8
|
Calvert MB, Mayer C, Titz A. An efficient synthesis of 1,6-anhydro- N-acetylmuramic acid from N-acetylglucosamine. Beilstein J Org Chem 2018; 13:2631-2636. [PMID: 30018663 PMCID: PMC5753053 DOI: 10.3762/bjoc.13.261] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 11/29/2017] [Indexed: 11/23/2022] Open
Abstract
A novel synthesis of 1,6-anhydro-N-acetylmuramic acid is described, which proceeds in only five steps from the cheap starting material N-acetylglucosamine. This efficient synthesis should enable future studies into the importance of 1,6-anhydromuramic acid in bacterial cell wall recycling processes.
Collapse
Affiliation(s)
- Matthew B Calvert
- Chemical Biology of Carbohydrates, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), D-66123 Saarbrücken, Germany.,Deutsches Zentrum für Infektionsforschung (DZIF), Standort Hannover-Braunschweig, Germany
| | - Christoph Mayer
- Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), Department of Microbiology and Biotechnology, University of Tübingen, Germany
| | - Alexander Titz
- Chemical Biology of Carbohydrates, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), D-66123 Saarbrücken, Germany.,Deutsches Zentrum für Infektionsforschung (DZIF), Standort Hannover-Braunschweig, Germany.,Department of Pharmacy, Saarland University, Saarbrücken, Germany
| |
Collapse
|
9
|
Okuyama M, Matsunaga K, Watanabe KI, Yamashita K, Tagami T, Kikuchi A, Ma M, Klahan P, Mori H, Yao M, Kimura A. Efficient synthesis of α-galactosyl oligosaccharides using a mutant Bacteroides thetaiotaomicron retaining α-galactosidase (BtGH97b). FEBS J 2017; 284:766-783. [PMID: 28103425 DOI: 10.1111/febs.14018] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Revised: 12/26/2016] [Accepted: 01/17/2017] [Indexed: 12/01/2022]
Abstract
The preparation of a glycosynthase, a catalytic nucleophile mutant of a glycosidase, is a well-established strategy for the effective synthesis of glycosidic linkages. However, glycosynthases derived from α-glycosidases can give poor yields of desired products because they require generally unstable β-glycosyl fluoride donors. Here, we investigate a transglycosylation catalyzed by a catalytic nucleophile mutant derived from a glycoside hydrolase family (GH) 97 α-galactosidase, using more stable β-galactosyl azide and α-galactosyl fluoride donors. The mutant enzyme catalyzes the glycosynthase reaction using β-galactosyl azide and α-galactosyl transfer from α-galactosyl fluoride with assistance of external anions. Formate was more effective at restoring transfer activity than azide. Kinetic analysis suggests that poor transglycosylation in the presence of the azide is because of low activity of the ternary complex between enzyme, β-galactosyl azide and acceptor. A three-dimensional structure of the mutant enzyme in complex with the transglycosylation product, β-lactosyl α-d-galactoside, was solved to elucidate the ligand-binding aspects of the α-galactosidase. Subtle differences at the β→α loops 1, 2 and 3 of the catalytic TIM barrel of the α-galactosidase from those of a homologous GH97 α-glucoside hydrolase seem to be involved in substrate recognitions. In particular, the Trp residues in β→α loop 1 have separate roles. Trp312 of the α-galactosidase appears to exclude the equatorial hydroxy group at C4 of glucosides, whereas the corresponding Trp residue in the α-glucoside hydrolase makes a hydrogen bond with this hydroxy group. The mechanism of α-galactoside recognition is conserved among GH27, 31, 36 and 97 α-galactosidases. DATABASE The atomic coordinates (code: 5E1Q) have been deposited in the Protein Data Bank.
Collapse
Affiliation(s)
- Masayuki Okuyama
- Laboratory of Molecular Enzymology, Research Faculty of Agriculture, Hokkaido University, Sapporo, Japan
| | - Kana Matsunaga
- Laboratory of Molecular Enzymology, Research Faculty of Agriculture, Hokkaido University, Sapporo, Japan
| | - Ken-Ichi Watanabe
- Laboratory of Molecular Enzymology, Research Faculty of Agriculture, Hokkaido University, Sapporo, Japan
| | - Keitaro Yamashita
- Laboratory of X-ray Structural Biology, Faculty of Advanced Life Science, Hokkaido University, Sapporo, Japan
| | - Takayoshi Tagami
- Laboratory of Molecular Enzymology, Research Faculty of Agriculture, Hokkaido University, Sapporo, Japan
| | - Asako Kikuchi
- Laboratory of Molecular Enzymology, Research Faculty of Agriculture, Hokkaido University, Sapporo, Japan
| | - Min Ma
- Laboratory of Molecular Enzymology, Research Faculty of Agriculture, Hokkaido University, Sapporo, Japan
| | - Patcharapa Klahan
- Laboratory of Molecular Enzymology, Research Faculty of Agriculture, Hokkaido University, Sapporo, Japan
| | - Haruhide Mori
- Laboratory of Molecular Enzymology, Research Faculty of Agriculture, Hokkaido University, Sapporo, Japan
| | - Min Yao
- Laboratory of X-ray Structural Biology, Faculty of Advanced Life Science, Hokkaido University, Sapporo, Japan
| | - Atsuo Kimura
- Laboratory of Molecular Enzymology, Research Faculty of Agriculture, Hokkaido University, Sapporo, Japan
| |
Collapse
|
10
|
Gampe CM, Tsukamoto H, Wang TSA, Walker S, Kahne D. Modular synthesis of diphospholipid oligosaccharide fragments of the bacterial cell wall and their use to study the mechanism of moenomycin and other antibiotics. Tetrahedron 2011; 67:9771-9778. [PMID: 22505780 PMCID: PMC3322638 DOI: 10.1016/j.tet.2011.09.114] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We present a flexible, modular route to GlcNAc-MurNAc-oligosaccharides that can be readily converted into peptidoglycan (PG) fragments to serve as reagents for the study of bacterial enzymes that are targets for antibiotics. Demonstrating the utility of these synthetic PG substrates, we show that the tetrasaccharide substrate lipid IV (3), but not the disaccharide substrate lipid II (2), significantly increases the concentration of moenomycin A required to inhibit a prototypical PG-glycosyltransferase (PGT). These results imply that lipid IV and moenomycin A bind to the same site on the enzyme. We also show the moenomycin A inhibits the formation of elongated polysaccharide product but does not affect length distribution. We conclude that moenomycin A blocks PG-strand initiation rather than elongation or chain termination. Synthetic access to diphospholipid oligosaccharides will enable further studies of bacterial cell wall synthesis with the long-term goal of identifying novel antibiotics.
Collapse
Affiliation(s)
- Christian M. Gampe
- Harvard University, Department of Chemistry and Chemical Biology, 12 Oxford Street, Cambridge, Massachusetts 02138, USA
| | - Hirokazu Tsukamoto
- Harvard University, Department of Chemistry and Chemical Biology, 12 Oxford Street, Cambridge, Massachusetts 02138, USA
| | - Tsung-Shing Andrew Wang
- Harvard University, Department of Chemistry and Chemical Biology, 12 Oxford Street, Cambridge, Massachusetts 02138, USA
| | - Suzanne Walker
- Harvard Medical School, Department of Microbiology and Molecular Genetics, Boston, Massachusetts 02115, USA
| | - Daniel Kahne
- Harvard University, Department of Chemistry and Chemical Biology, 12 Oxford Street, Cambridge, Massachusetts 02138, USA
| |
Collapse
|