1
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Rao D, Zhu L, Liu W, Guo Z. Molecular Mechanism of Double-Displacement Retaining β-Kdo Glycosyltransferase WbbB. J Phys Chem B 2024. [PMID: 39051443 DOI: 10.1021/acs.jpcb.4c02073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/27/2024]
Abstract
Glycosyltransferases (GTs) are pivotal enzymes involved in glycosidic bond synthesis, which can lead to either retention or inversion of the glycosyl moiety's anomeric configuration. However, the catalytic mechanism for retaining GTs remains a subject of controversy. In this study, we employ MD and QM/MM metadynamics to investigate the double-displacement catalytic mechanism of the retaining β-Kdo transferase WbbB. Our findings demonstrate that the nucleophile Asp232 initiates the reaction by attacking the sugar ring containing a carboxylate at the anomeric position, forming a covalent adduct. Subsequently, the adduct undergoes a rotational rearrangement, ensuring proper orientation of the anomeric carbon for the acceptor substrate. In the second step, Glu158 acts as the catalytic base to abstract the proton of the acceptor substrate to complete the transglycosylation reaction. Notably, His265 does not function as the anticipated catalytic acid; instead, it stabilizes the phosphate group through H-bonding interactions. Our simulations support the double-displacement mechanism implicated from the crystallographic studies of WbbB. This mechanism deviates from the common SNi-type and retaining glycoside hydrolase mechanisms, thereby expanding our understanding of GT catalytic mechanisms.
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Affiliation(s)
- Deming Rao
- School of Life Science and Technology, Wuhan Polytechnic University, Wuhan 430023, People's Republic of China
| | - Lin Zhu
- School of Life Science and Technology, Wuhan Polytechnic University, Wuhan 430023, People's Republic of China
| | - Weiqiong Liu
- State Key Laboratory of Food Science and Resources, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, People's Republic of China
- School of Biotechnology and Key Laboratory of Industrial Biotechnology Ministry of Education, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, People's Republic of China
- International Joint Laboratory on Food Safety, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, People's Republic of China
| | - Zhiyong Guo
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Hubei Key Laboratory of Industrial Biotechnology, School of Life Sciences, Hubei University, Wuhan 430062, People's Republic of China
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2
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Sirirungruang S, Blay V, Scott YF, Pereira JH, Hammel M, Barnum CR, Adams PD, Shih PM. Structural and biochemical basis for regiospecificity of the flavonoid glycosyltransferase UGT95A1. J Biol Chem 2024:107602. [PMID: 39059496 DOI: 10.1016/j.jbc.2024.107602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2024] [Revised: 07/02/2024] [Accepted: 07/15/2024] [Indexed: 07/28/2024] Open
Abstract
Glycosylation is a predominant strategy plants employ to fine-tune the properties of small molecule metabolites to affect their bioactivity, transport, and storage. It is also important in biotechnology and medicine as many glycosides are utilized in human health. Small molecule glycosylation is largely carried out by family 1 glycosyltransferases. Here, we report a structural and biochemical investigation of UGT95A1, a family 1 GT enzyme from Pilosella officinarum that exhibits a strong, unusual regiospecificity for the 3'-O position of flavonoid acceptor substrate luteolin. We obtained an apo crystal structure to help drive the analyses of a series of binding site mutants, revealing that while most residues are tolerant to mutations, key residues M145 and D464 are important for overall glycosylation activity. Interestingly, E347 is crucial for maintaining the strong preference for 3'-O glycosylation, while R462 can be mutated to increase regioselectivity. The structural determinants of regioselectivity were further confirmed in homologous enzymes. Our study also suggests that the enzyme contains large, highly dynamic, disordered regions. We showed that while most disordered regions of the protein have little to no implication in catalysis, the disordered regions conserved among investigated homologues are important to both the overall efficiency and regiospecificity of the enzyme. This report represents a comprehensive in-depth analysis of a family 1 GT enzyme with a unique substrate regiospecificity and may provide a basis for enzyme functional prediction and engineering.
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Affiliation(s)
- Sasilada Sirirungruang
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA; Feedstocks Division, Joint BioEnergy Institute, Emeryville, CA, USA; Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA; Center for Biomolecular Structure, Function and Application, Suranaree University of Technology, Nakhon Ratchasima, Thailand
| | - Vincent Blay
- Biofuels and Bioproducts Division, Joint BioEnergy Institute, Emeryville, CA, USA
| | - Yasmine F Scott
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | - Jose H Pereira
- Technology Division, Joint BioEnergy Institute, Emeryville, CA, USA; Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Michal Hammel
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Collin R Barnum
- Biochemistry, Molecular, Cellular and Developmental Biology Graduate Group, University of California, Davis, CA, University of California, Davis, CA, USA
| | - Paul D Adams
- Technology Division, Joint BioEnergy Institute, Emeryville, CA, USA; Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Patrick M Shih
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA; Feedstocks Division, Joint BioEnergy Institute, Emeryville, CA, USA; Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA; Innovative Genomics Institute, University of California, Berkeley, CA, USA.
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3
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Xu S, Zhao J, Liu X, Yang X, Xu Z, Gao Y, Ma Y, Yang H. Structures of SenB and SenA enzymes from Variovorax paradoxus provide insights into carbon-selenium bond formation in selenoneine biosynthesis. Heliyon 2024; 10:e32888. [PMID: 38994077 PMCID: PMC11237966 DOI: 10.1016/j.heliyon.2024.e32888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2024] [Revised: 06/10/2024] [Accepted: 06/11/2024] [Indexed: 07/13/2024] Open
Abstract
Selenoneine, an ergothioneine analog, is important for antioxidation and detoxification. SenB and SenA are two crucial enzymes that form carbon-selenium bonds in the selenoneine biosynthetic pathway. To investigate their underlying catalytic mechanisms, we obtained complex structures of SenB with its substrate UDP-N-acetylglucosamine (UDP-GlcNAc) and SenA with N-α-trimethyl histidine (TMH). SenB adopts a type-B glycosyltransferase fold. Structural and functional analysis of the interaction network at the active center provide key information on substrate recognition and suggest a metal-ion-independent, inverting mechanism is utilized for SenB-mediated selenoglycoside formation. Moreover, the complex structure of SenA with TMH and enzymatic activity assays highlight vital residues that control substrate binding and specificity. Based on the conserved structure and substrate-binding pocket of the type I sulfoxide synthase EgtB in the ergothioneine biosynthetic pathway, a similar reaction mechanism was proposed for the formation of C-Se bonds by SenA. The structures provide knowledge on selenoneine synthesis and lay groundwork for further applications of this pathway.
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Affiliation(s)
- Sihan Xu
- Shanghai Institute for Advanced Immunochemical Studies and School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Jinyi Zhao
- Shanghai Institute for Advanced Immunochemical Studies and School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Xiang Liu
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Center for Cell Response, College of Life Sciences, College of Pharmacy, Nankai University, Tianjin, China
| | - Xiuna Yang
- Shanghai Institute for Advanced Immunochemical Studies and School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Zili Xu
- Shanghai Institute for Advanced Immunochemical Studies and School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Yan Gao
- Shanghai Institute for Advanced Immunochemical Studies and School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Yuanyuan Ma
- Shanghai Institute for Advanced Immunochemical Studies and School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Haitao Yang
- Shanghai Institute for Advanced Immunochemical Studies and School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China
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4
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Li T, Borg AJE, Krammer L, Weber H, Breinbauer R, Nidetzky B. Discovery, characterization, and comparative analysis of new UGT72 and UGT84 family glycosyltransferases. Commun Chem 2024; 7:147. [PMID: 38942997 PMCID: PMC11213884 DOI: 10.1038/s42004-024-01231-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Accepted: 06/20/2024] [Indexed: 06/30/2024] Open
Abstract
Glycosylated derivatives of natural product polyphenols display a spectrum of biological activities, rendering them critical for both nutritional and pharmacological applications. Their enzymatic synthesis by glycosyltransferases is frequently constrained by the limited repertoire of characterized enzyme-catalyzed transformations. Here, we explore the glycosylation capabilities and substrate preferences of newly identified plant uridine diphosphate (UDP)-dependent glycosyltransferases (UGTs) within the UGT72 and UGT84 families, with particular focus on natural polyphenol glycosylation from UDP-glucose. Four UGTs are classified according to their phylogenetic relationships and reaction products, identifying them as biocatalysts for either glucoside (UGT72 enzymes) or glucose ester (UGT84 members) formation from selected phenylpropanoid compounds. Detailed kinetic evaluations expose the unique attributes of these enzymes, including their specific activities and regio-selectivities towards diverse polyphenolic substrates, with product characterizations validating the capacity of UGT84 family members to perform di-O-glycosylation on flavones. Sequence analysis coupled with structural predictions through AlphaFold reveal an unexpected absence of a conserved threonine residue across all four enzymes, a trait previously linked to pentosyltransferases. This comparative analysis broadens the understood substrate specificity range for UGT72 and UGT84 enzymes, enhancing our understanding of their utility in the production of natural phenolic glycosides. The findings from this in-depth characterization provide valuable insights into the functional versatility of UGT-mediated reactions.
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Affiliation(s)
- Tuo Li
- Institute of Biotechnology and Biochemical Engineering, Graz University of Technology, NAWI Graz, Petersgasse 12/1, 8010, Graz, Austria
| | - Annika J E Borg
- Institute of Biotechnology and Biochemical Engineering, Graz University of Technology, NAWI Graz, Petersgasse 12/1, 8010, Graz, Austria
| | - Leo Krammer
- Institute of Organic Chemistry, Graz University of Technology, NAWI Graz, Stremayrgasse 9, 8010, Graz, Austria
| | - Hansjörg Weber
- Institute of Organic Chemistry, Graz University of Technology, NAWI Graz, Stremayrgasse 9, 8010, Graz, Austria
| | - Rolf Breinbauer
- Institute of Organic Chemistry, Graz University of Technology, NAWI Graz, Stremayrgasse 9, 8010, Graz, Austria
| | - Bernd Nidetzky
- Institute of Biotechnology and Biochemical Engineering, Graz University of Technology, NAWI Graz, Petersgasse 12/1, 8010, Graz, Austria.
- Austrian Centre of Industrial Biotechnology (acib), Krenngasse 37, 8010, Graz, Austria.
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5
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Harding-Larsen D, Madsen CD, Teze D, Kittilä T, Langhorn MR, Gharabli H, Hobusch M, Otalvaro FM, Kırtel O, Bidart GN, Mazurenko S, Travnik E, Welner DH. GASP: A Pan-Specific Predictor of Family 1 Glycosyltransferase Acceptor Specificity Enabled by a Pipeline for Substrate Feature Generation and Large-Scale Experimental Screening. ACS OMEGA 2024; 9:27278-27288. [PMID: 38947828 PMCID: PMC11209901 DOI: 10.1021/acsomega.4c01583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Revised: 05/27/2024] [Accepted: 05/29/2024] [Indexed: 07/02/2024]
Abstract
Glycosylation represents a major chemical challenge; while it is one of the most common reactions in Nature, conventional chemistry struggles with stereochemistry, regioselectivity, and solubility issues. In contrast, family 1 glycosyltransferase (GT1) enzymes can glycosylate virtually any given nucleophilic group with perfect control over stereochemistry and regioselectivity. However, the appropriate catalyst for a given reaction needs to be identified among the tens of thousands of available sequences. Here, we present the glycosyltransferase acceptor specificity predictor (GASP) model, a data-driven approach to the identification of reactive GT1:acceptor pairs. We trained a random forest-based acceptor predictor on literature data and validated it on independent in-house generated data on 1001 GT1:acceptor pairs, obtaining an AUROC of 0.79 and a balanced accuracy of 72%. The performance was stable even in the case of completely new GT1s and acceptors not present in the training data set, highlighting the pan-specificity of GASP. Moreover, the model is capable of parsing all known GT1 sequences, as well as all chemicals, the latter through a pipeline for the generation of 153 chemical features for a given molecule taking the CID or SMILES as input (freely available at https://github.com/degnbol/GASP). To investigate the power of GASP, the model prediction probability scores were compared to GT1 substrate conversion yields from a newly published data set, with the top 50% of GASP predictions corresponding to reactions with >50% synthetic yields. The model was also tested in two comparative case studies: glycosylation of the antihelminth drug niclosamide and the plant defensive compound DIBOA. In the first study, the model achieved an 83% hit rate, outperforming a hit rate of 53% from a random selection assay. In the second case study, the hit rate of GASP was 50%, and while being lower than the hit rate of 83% using expert-selected enzymes, it provides a reasonable performance for the cases when an expert opinion is unavailable. The hierarchal importance of the generated chemical features was investigated by negative feature selection, revealing properties related to cyclization and atom hybridization status to be the most important characteristics for accurate prediction. Our study provides a GT1:acceptor predictor which can be trained on other data sets enabled by the automated feature generation pipelines. We also release the new in-house generated data set used for testing of GASP to facilitate the future development of GT1 activity predictors and their robust benchmarking.
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Affiliation(s)
- David Harding-Larsen
- DTU
Biosustain, Technical University of Denmark, Kemitorvet 220, Lyngby, Denmark 2800
| | - Christian Degnbol Madsen
- DTU
Biosustain, Technical University of Denmark, Kemitorvet 220, Lyngby, Denmark 2800
- The
University of Melbourne Faculty of Science, Melbourne Integrative
Genomics, University of Melbourne, Building 184, Royal Parade, Parkville
3010, Melbourne, VIC 3052, Australia
| | - David Teze
- DTU
Biosustain, Technical University of Denmark, Kemitorvet 220, Lyngby, Denmark 2800
| | - Tiia Kittilä
- DTU
Biosustain, Technical University of Denmark, Kemitorvet 220, Lyngby, Denmark 2800
| | | | - Hani Gharabli
- DTU
Biosustain, Technical University of Denmark, Kemitorvet 220, Lyngby, Denmark 2800
| | - Mandy Hobusch
- DTU
Biosustain, Technical University of Denmark, Kemitorvet 220, Lyngby, Denmark 2800
| | - Felipe Mejia Otalvaro
- DTU
Biosustain, Technical University of Denmark, Kemitorvet 220, Lyngby, Denmark 2800
| | - Onur Kırtel
- DTU
Biosustain, Technical University of Denmark, Kemitorvet 220, Lyngby, Denmark 2800
| | - Gonzalo Nahuel Bidart
- DTU
Biosustain, Technical University of Denmark, Kemitorvet 220, Lyngby, Denmark 2800
| | - Stanislav Mazurenko
- Department
of Experimental Biology and RECETOX, Faculty of Science, Masarykova Univerzita, Kamenice 5/A4, Brno 625 00, Czech Republic
- International
Clinical Research Center, St. Anne’s
University Hospital Brno, Pekarska 53, Brno 656
91, Czech Republic
| | - Evelyn Travnik
- DTU
Biosustain, Technical University of Denmark, Kemitorvet 220, Lyngby, Denmark 2800
| | - Ditte Hededam Welner
- DTU
Biosustain, Technical University of Denmark, Kemitorvet 220, Lyngby, Denmark 2800
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6
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Gharabli H, Welner DH. The sugar donor specificity of plant family 1 glycosyltransferases. Front Bioeng Biotechnol 2024; 12:1396268. [PMID: 38756413 PMCID: PMC11096472 DOI: 10.3389/fbioe.2024.1396268] [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: 03/05/2024] [Accepted: 04/19/2024] [Indexed: 05/18/2024] Open
Abstract
Plant family 1 glycosyltransferases (UGTs) represent a formidable tool to produce valuable natural and novel glycosides. Their regio- and stereo-specific one-step glycosylation mechanism along with their inherent wide acceptor scope are desirable traits in biotechnology. However, their donor scope and specificity are not well understood. Since different sugars have different properties in vivo and in vitro, the ability to easily glycodiversify target acceptors is desired, and this depends on our improved understanding of the donor binding site. In the aim to unlock the full potential of UGTs, studies have attempted to elucidate the structure-function relationship governing their donor specificity. These efforts have revealed a complex phenomenon, and general principles valid for multiple enzymes are elusive. Here, we review the studies of UGT donor specificity, and attempt to group the information into key concepts which can help shape future research. We zoom in on the family-defining PSPG motif, on two loop residues reported to interact with the C6 position of the sugar, and on the role of active site arginines in donor specificity. We continue to discuss attempts to alter and expand the donor specificity by enzyme engineering, and finally discuss future research directions.
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Affiliation(s)
| | - Ditte Hededam Welner
- The Novo Nordisk Center for Biosustainability, Technical University of Denmark, Kongens Lyngby, Denmark
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7
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Bretagne D, Pâris A, Matthews D, Fougère L, Burrini N, Wagner GK, Daniellou R, Lafite P. "Mix and match" auto-assembly of glycosyltransferase domains delivers biocatalysts with improved substrate promiscuity. J Biol Chem 2024; 300:105747. [PMID: 38354783 PMCID: PMC10937113 DOI: 10.1016/j.jbc.2024.105747] [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: 07/21/2023] [Revised: 01/25/2024] [Accepted: 02/08/2024] [Indexed: 02/16/2024] Open
Abstract
Glycosyltransferases (GT) catalyze the glycosylation of bioactive natural products, including peptides and proteins, flavonoids, and sterols, and have been extensively used as biocatalysts to generate glycosides. However, the often narrow substrate specificity of wild-type GTs requires engineering strategies to expand it. The GT-B structural family is constituted by GTs that share a highly conserved tertiary structure in which the sugar donor and acceptor substrates bind in dedicated domains. Here, we have used this selective binding feature to design an engineering process to generate chimeric glycosyltransferases that combine auto-assembled domains from two different GT-B enzymes. Our approach enabled the generation of a stable dimer with broader substrate promiscuity than the parent enzymes that were related to relaxed interactions between domains in the dimeric GT-B. Our findings provide a basis for the development of a novel class of heterodimeric GTs with improved substrate promiscuity for applications in biotechnology and natural product synthesis.
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Affiliation(s)
- Damien Bretagne
- Institut de Chimie Organique et Analytique (ICOA), UMR 7311 CNRS-Université d'Orléans, Université d'Orléans, Orléans Cedex 2, France; School of Pharmacy, Queen's University Belfast, Medical Biology Centre, Belfast, United Kingdom
| | - Arnaud Pâris
- Institut de Chimie Organique et Analytique (ICOA), UMR 7311 CNRS-Université d'Orléans, Université d'Orléans, Orléans Cedex 2, France
| | - David Matthews
- School of Pharmacy, Queen's University Belfast, Medical Biology Centre, Belfast, United Kingdom
| | - Laëtitia Fougère
- Institut de Chimie Organique et Analytique (ICOA), UMR 7311 CNRS-Université d'Orléans, Université d'Orléans, Orléans Cedex 2, France
| | - Nastassja Burrini
- Institut de Chimie Organique et Analytique (ICOA), UMR 7311 CNRS-Université d'Orléans, Université d'Orléans, Orléans Cedex 2, France
| | - Gerd K Wagner
- School of Pharmacy, Queen's University Belfast, Medical Biology Centre, Belfast, United Kingdom
| | - Richard Daniellou
- Institut de Chimie Organique et Analytique (ICOA), UMR 7311 CNRS-Université d'Orléans, Université d'Orléans, Orléans Cedex 2, France; Chaire de Cosmétologie, AgroParisTech, Orléans, France; Université Paris-Saclay, INRAE, AgroParisTech, Micalis Institute, Jouy-en-Josas, France.
| | - Pierre Lafite
- Institut de Chimie Organique et Analytique (ICOA), UMR 7311 CNRS-Université d'Orléans, Université d'Orléans, Orléans Cedex 2, France.
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8
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Huang W, Song J, Sun T, He Y, Li X, Deng Z, Long F. Substrate binding and catalytic mechanism of the Se-glycosyltransferase SenB in the biosynthesis of selenoneine. Nat Commun 2024; 15:1659. [PMID: 38395953 PMCID: PMC10891094 DOI: 10.1038/s41467-024-46065-6] [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: 11/12/2023] [Accepted: 02/13/2024] [Indexed: 02/25/2024] Open
Abstract
Selenium is an essential multifunctional trace element in diverse organisms. The only Se-glycosyltransferase identified that catalyzes the incorporation of selenium in selenoneine biosynthesis is SenB from Variovorax paradoxus. Although the biochemical function of SenB has been investigated, its substrate specificity, structure, and catalytic mechanism have not been elucidated. Here, we reveal that SenB exhibits sugar donor promiscuity and can utilize six UDP-sugars to generate selenosugars. We report crystal structures of SenB complexed with different UDP-sugars. The key elements N20/T23/E231 contribute to the sugar donor selectivity of SenB. A proposed catalytic mechanism is tested by structure-guided mutagenesis, revealing that SenB yields selenosugars by forming C-Se glycosidic bonds via spontaneous deprotonation and disrupting Se-P bonds by nucleophilic water attack, which is initiated by the critical residue K158. Furthermore, we functionally and structurally characterize two other Se-glycosyltransferases, CbSenB from Comamonadaceae bacterium and RsSenB from Ramlibacter sp., which also exhibit sugar donor promiscuity.
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Affiliation(s)
- Wei Huang
- Department of Neurosurgery, Zhongnan Hospital of Wuhan University, School of Pharmaceutical Sciences, Wuhan University, Wuhan, 430071, China
- Ministry of Education Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, School of Pharmaceutical Sciences, Wuhan University, Wuhan, 430071, China
| | - Jun Song
- Department of Neurosurgery, Zhongnan Hospital of Wuhan University, School of Pharmaceutical Sciences, Wuhan University, Wuhan, 430071, China
- Ministry of Education Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, School of Pharmaceutical Sciences, Wuhan University, Wuhan, 430071, China
| | - Tianxue Sun
- Ministry of Education Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, School of Pharmaceutical Sciences, Wuhan University, Wuhan, 430071, China
| | - Yue He
- Ministry of Education Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, School of Pharmaceutical Sciences, Wuhan University, Wuhan, 430071, China
| | - Xiang Li
- Department of Neurosurgery, Zhongnan Hospital of Wuhan University, School of Pharmaceutical Sciences, Wuhan University, Wuhan, 430071, China
| | - Zixin Deng
- Ministry of Education Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, School of Pharmaceutical Sciences, Wuhan University, Wuhan, 430071, China
| | - Feng Long
- Department of Neurosurgery, Zhongnan Hospital of Wuhan University, School of Pharmaceutical Sciences, Wuhan University, Wuhan, 430071, China.
- Ministry of Education Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, School of Pharmaceutical Sciences, Wuhan University, Wuhan, 430071, China.
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9
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Yang L, Yang M, Deng Z, Hou X, Zheng X, Ping Q, Rao Y, Shi J, Zhang Y. Selective synthesis of rebaudioside M2 through structure-guided engineering of glycosyltransferase UGT94D1. Front Bioeng Biotechnol 2024; 12:1334427. [PMID: 38375456 PMCID: PMC10875103 DOI: 10.3389/fbioe.2024.1334427] [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: 11/07/2023] [Accepted: 01/12/2024] [Indexed: 02/21/2024] Open
Abstract
Rebaudioside M2 (Reb M2), a novel steviol glycoside derivative, has limited industrial applications due to its low synthetic yield and selectivity. Herein, we identify UGT94D1 as a selective glycosyltransferase for rebaudioside D (Reb D), leading to the production of a mono β-1,6-glycosylated derivative, Reb M2. A variant UGT94D1-F119I/D188P was developed through protein engineering. This mutant exhibited a 6.33-fold improvement in catalytic efficiency, and produced Reb M2 with 92% yield. Moreover, molecular dynamics simulations demonstrated that UGT94D1-F119I/D188P exhibited a shorter distance between the nucleophilic oxygen (OH6) of the substrate Reb D and uridine diphosphate glucose, along with an increased Ophosphate-C1-Oacceptor angle, thus improving the catalytic activity of the enzyme. Therefore, this study provides an efficient method for the selective synthesis of Reb M2 and paves the way for its applications in various fields.
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Affiliation(s)
- Lifeng Yang
- School of Life Sciences and Health Engineering, Jiangnan University, Wuxi, China
- School of Chemical and Material Engineering, Jiangnan University, Wuxi, China
| | - Mengliang Yang
- School of Biotechnology, Jiangnan University, Wuxi, China
| | - Zhiwei Deng
- School of Biotechnology, Jiangnan University, Wuxi, China
| | - Xiaodong Hou
- School of Biotechnology, Jiangnan University, Wuxi, China
| | - Xiangting Zheng
- School of Life Sciences and Health Engineering, Jiangnan University, Wuxi, China
| | - Qian Ping
- School of Life Sciences and Health Engineering, Jiangnan University, Wuxi, China
| | - Yijian Rao
- School of Biotechnology, Jiangnan University, Wuxi, China
| | - Jinsong Shi
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Life Sciences and Health Engineering, Jiangnan University, Wuxi, China
| | - Yan Zhang
- School of Life Sciences and Health Engineering, Jiangnan University, Wuxi, China
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10
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Tang SN, Barnum CR, Szarzanowicz MJ, Sirirungruang S, Shih PM. Harnessing Plant Sugar Metabolism for Glycoengineering. BIOLOGY 2023; 12:1505. [PMID: 38132331 PMCID: PMC10741112 DOI: 10.3390/biology12121505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 11/27/2023] [Accepted: 12/04/2023] [Indexed: 12/23/2023]
Abstract
Plants possess an innate ability to generate vast amounts of sugar and produce a range of sugar-derived compounds that can be utilized for applications in industry, health, and agriculture. Nucleotide sugars lie at the unique intersection of primary and specialized metabolism, enabling the biosynthesis of numerous molecules ranging from small glycosides to complex polysaccharides. Plants are tolerant to perturbations to their balance of nucleotide sugars, allowing for the overproduction of endogenous nucleotide sugars to push flux towards a particular product without necessitating the re-engineering of upstream pathways. Pathways to produce even non-native nucleotide sugars may be introduced to synthesize entirely novel products. Heterologously expressed glycosyltransferases capable of unique sugar chemistries can further widen the synthetic repertoire of a plant, and transporters can increase the amount of nucleotide sugars available to glycosyltransferases. In this opinion piece, we examine recent successes and potential future uses of engineered nucleotide sugar biosynthetic, transport, and utilization pathways to improve the production of target compounds. Additionally, we highlight current efforts to engineer glycosyltransferases. Ultimately, the robust nature of plant sugar biochemistry renders plants a powerful chassis for the production of target glycoconjugates and glycans.
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Affiliation(s)
- Sophia N. Tang
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA;
- Feedstocks Division, Joint BioEnergy Institute, Emeryville, CA 94608, USA; (M.J.S.)
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94710, USA
| | - Collin R. Barnum
- Biochemistry, Molecular, Cellular and Developmental Biology Graduate Group, University of California, Davis, CA 95616, USA
| | - Matthew J. Szarzanowicz
- Feedstocks Division, Joint BioEnergy Institute, Emeryville, CA 94608, USA; (M.J.S.)
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94710, USA
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA
| | - Sasilada Sirirungruang
- Feedstocks Division, Joint BioEnergy Institute, Emeryville, CA 94608, USA; (M.J.S.)
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94710, USA
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA
| | - Patrick M. Shih
- Feedstocks Division, Joint BioEnergy Institute, Emeryville, CA 94608, USA; (M.J.S.)
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94710, USA
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720, USA
- Innovative Genomics Institute, University of California, Berkeley, CA 94720, USA
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11
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de Boer RM, H Hvid DE, Davail E, Vaitkus D, Duus JØ, Welner DH, Teze D. Promiscuous Yet Specific: A Methionine-Aromatic Interaction Drives the Reaction Scope of the Family 1 Glycosyltransferase GmUGT88E3 from Soybean. Biochemistry 2023; 62:3343-3346. [PMID: 38009918 DOI: 10.1021/acs.biochem.3c00494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
Family 1 glycosyltransferases (GT1s, UGTs) catalyze the regioselective glycosylation of natural products in a single step. We identified GmUGT88E3 as a particularly promising biocatalyst able to produce a variety of pure, single glycosidic products from polyphenols with high chemical yields. We investigated this particularly desirable duality toward specificity, i.e., promiscuous toward acceptors while regiospecific. Using high-field NMR, kinetic characterization, molecular dynamics simulations, and mutagenesis studies, we uncovered that the main molecular determinant of GmUGT88E3 specificity is a methionine-aromatic bridge, an interaction often present in protein structures but never reported for enzyme-substrate interactions. Here, mutating Met127 led to inactive proteins or 100-fold reduced activity.
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Affiliation(s)
- Ruben M de Boer
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, DK- 2800 Kongens Lyngby, Denmark
| | - Dan E H Hvid
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, DK- 2800 Kongens Lyngby, Denmark
- Department of Chemistry, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Elisa Davail
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, DK- 2800 Kongens Lyngby, Denmark
| | - Dovydas Vaitkus
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, DK- 2800 Kongens Lyngby, Denmark
| | - Jens Ø Duus
- Department of Chemistry, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Ditte H Welner
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, DK- 2800 Kongens Lyngby, Denmark
| | - David Teze
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, DK- 2800 Kongens Lyngby, Denmark
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12
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Wang M, Ji Q, Lai B, Liu Y, Mei K. Structure-function and engineering of plant UDP-glycosyltransferase. Comput Struct Biotechnol J 2023; 21:5358-5371. [PMID: 37965058 PMCID: PMC10641439 DOI: 10.1016/j.csbj.2023.10.046] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 10/23/2023] [Accepted: 10/23/2023] [Indexed: 11/16/2023] Open
Abstract
Natural products synthesized by plants have substantial industrial and medicinal values and are therefore attracting increasing interest in various related industries. Among the key enzyme families involved in the biosynthesis of natural products, uridine diphosphate-dependent glycosyltransferases (UGTs) play a crucial role in plants. In recent years, significant efforts have been made to elucidate the catalytic mechanisms and substrate recognition of plant UGTs and to improve them for desired functions. In this review, we presented a comprehensive overview of all currently published structures of plant UGTs, along with in-depth analyses of the corresponding catalytic and substrate recognition mechanisms. In addition, we summarized and evaluated the protein engineering strategies applied to improve the catalytic activities of plant UGTs, with a particular focus on high-throughput screening methods. The primary objective of this review is to provide readers with a comprehensive understanding of plant UGTs and to serve as a valuable reference for the latest techniques used to improve their activities.
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Affiliation(s)
- Mengya Wang
- Tianjin Key Laboratory for Modern Drug Delivery and High Efficiency, School of Pharmaceutical Science and Technology, Tianjin University, Tianjin 300072, China
- Key Laboratory of Systems Bioengineering, Ministry of Education, Tianjin University, Tianjin 300072, China
| | - Qiushuang Ji
- Tianjin Key Laboratory for Modern Drug Delivery and High Efficiency, School of Pharmaceutical Science and Technology, Tianjin University, Tianjin 300072, China
- Key Laboratory of Systems Bioengineering, Ministry of Education, Tianjin University, Tianjin 300072, China
| | - Bin Lai
- BMBF junior research group Biophotovoltaics, Department of Environmental Microbiology, Helmholtz Centre for Environmental Research - UFZ, Leipzig 04318, Germany
| | - Yirong Liu
- Tianjin Key Laboratory for Modern Drug Delivery and High Efficiency, School of Pharmaceutical Science and Technology, Tianjin University, Tianjin 300072, China
- Key Laboratory of Systems Bioengineering, Ministry of Education, Tianjin University, Tianjin 300072, China
| | - Kunrong Mei
- Tianjin Key Laboratory for Modern Drug Delivery and High Efficiency, School of Pharmaceutical Science and Technology, Tianjin University, Tianjin 300072, China
- Key Laboratory of Systems Bioengineering, Ministry of Education, Tianjin University, Tianjin 300072, China
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13
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Liao J, Lederer V, Bardhi A, Zou Z, Hoffmann TD, Sun G, Song C, Hoffmann T, Schwab W. Acceptors and Effectors Alter Substrate Inhibition Kinetics of a Plant Glucosyltransferase NbUGT72AY1 and Its Mutants. Int J Mol Sci 2023; 24:ijms24119542. [PMID: 37298492 DOI: 10.3390/ijms24119542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 05/22/2023] [Accepted: 05/25/2023] [Indexed: 06/12/2023] Open
Abstract
One of the main obstacles in biocatalysis is the substrate inhibition (SI) of enzymes that play important roles in biosynthesis and metabolic regulation in organisms. The promiscuous glycosyltransferase UGT72AY1 from Nicotiana benthamiana is strongly substrate-inhibited by hydroxycoumarins (inhibitory constant Ki < 20 µM), but only weakly inhibited when monolignols are glucosylated (Ki > 1000 µM). Apocarotenoid effectors reduce the inherent UDP-glucose glucohydrolase activity of the enzyme and attenuate the SI by scopoletin derivatives, which could also be achieved by mutations. Here, we studied the kinetic profiles of different phenols and used the substrate analog vanillin, which has shown atypical Michaelis-Menten kinetics in previous studies, to examine the effects of different ligands and mutations on the SI of NbUGT72AY1. Coumarins had no effect on enzymatic activity, whereas apocarotenoids and fatty acids strongly affected SI kinetics by increasing the inhibition constant Ki. Only the F87I mutant and a chimeric version of the enzyme showed weak SI with the substrate vanillin, but all mutants exhibited mild SI when sinapaldehyde was used as an acceptor. In contrast, stearic acid reduced the transferase activity of the mutants to varying degrees. The results not only confirm the multi-substrate functionality of NbUGT72AY1, but also reveal that the enzymatic activity of this protein can be fine-tuned by external metabolites such as apocarotenoids and fatty acids that affect SI. Since these signals are generated during plant cell destruction, NbUGT72AY1 likely plays an important role in plant defense by participating in the production of lignin in the cell wall and providing direct protection through the formation of toxic phytoalexins.
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Affiliation(s)
- Jieren Liao
- Biotechnology of Natural Products, Technische Universität München, Liesel-Beckmann-Str. 1, 85354 Freising, Germany
| | - Veronika Lederer
- Biotechnology of Natural Products, Technische Universität München, Liesel-Beckmann-Str. 1, 85354 Freising, Germany
| | - Alba Bardhi
- Biotechnology of Natural Products, Technische Universität München, Liesel-Beckmann-Str. 1, 85354 Freising, Germany
| | - Zhiwei Zou
- Biotechnology of Natural Products, Technische Universität München, Liesel-Beckmann-Str. 1, 85354 Freising, Germany
| | - Timothy D Hoffmann
- Biotechnology of Natural Products, Technische Universität München, Liesel-Beckmann-Str. 1, 85354 Freising, Germany
| | - Guangxin Sun
- Biotechnology of Natural Products, Technische Universität München, Liesel-Beckmann-Str. 1, 85354 Freising, Germany
| | - Chuankui Song
- State Key Laboratory of Tea Plant Biology and Utilization, International Joint Laboratory on Tea Chemistry and Health Effects, Anhui Agricultural University, Hefei 230036, China
| | - Thomas Hoffmann
- Biotechnology of Natural Products, Technische Universität München, Liesel-Beckmann-Str. 1, 85354 Freising, Germany
| | - Wilfried Schwab
- Biotechnology of Natural Products, Technische Universität München, Liesel-Beckmann-Str. 1, 85354 Freising, Germany
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14
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Liao J, Sun G, Kurze E, Steinchen W, Hoffmann TD, Song C, Zou Z, Hoffmann T, Schwab WG. Subfunctionalization of a monolignol to a phytoalexin glucosyltransferase is accompanied by substrate inhibition. PLANT COMMUNICATIONS 2023; 4:100506. [PMID: 36566353 DOI: 10.1016/j.xplc.2022.100506] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 11/16/2022] [Accepted: 12/16/2022] [Indexed: 05/11/2023]
Abstract
Uridine diphosphate-dependent glycosyltransferases (UGTs) mediate the glycosylation of plant metabolites, thereby altering their physicochemical properties and bioactivities. Plants possess numerous UGT genes, with the encoded enzymes often glycosylating multiple substrates and some exhibiting substrate inhibition kinetics, but the biological function and molecular basis of these phenomena are not fully understood. The promiscuous monolignol/phytoalexin glycosyltransferase NbUGT72AY1 exhibits substrate inhibition (Ki) at 4 μM scopoletin, whereas the highly homologous monolignol StUGT72AY2 is inhibited at 190 μM. We therefore used hydrogen/deuterium exchange mass spectrometry and structure-based mutational analyses of both proteins and introduced NbUGT72AY1 residues into StUGT72AY2 and vice versa to study promiscuity and substrate inhibition of UGTs. A single F87I and chimeric mutant of NbUGT72AY1 showed significantly reduced scopoletin substrate inhibition, whereas its monolignol glycosylation activity was almost unaffected. Reverse mutations in StUGT72AY2 resulted in increased scopoletin glycosylation, leading to enhanced promiscuity, which was accompanied by substrate inhibition. Studies of 3D structures identified open and closed UGT conformers, allowing visualization of the dynamics of conformational changes that occur during catalysis. Previously postulated substrate access tunnels likely serve as drainage channels. The results suggest a two-site model in which the second substrate molecule binds near the catalytic site and blocks product release. Mutational studies showed that minor changes in amino acid sequence can enhance the promiscuity of the enzyme and add new capabilities such as substrate inhibition without affecting existing functions. The proposed subfunctionalization mechanism of expanded promiscuity may play a role in enzyme evolution and highlights the importance of promiscuous enzymes in providing new functions.
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Affiliation(s)
- Jieren Liao
- Biotechnology of Natural Products, Technische Universität München, Liesel-Beckmann-Str. 1, 85354 Freising, Germany
| | - Guangxin Sun
- Biotechnology of Natural Products, Technische Universität München, Liesel-Beckmann-Str. 1, 85354 Freising, Germany
| | - Elisabeth Kurze
- Biotechnology of Natural Products, Technische Universität München, Liesel-Beckmann-Str. 1, 85354 Freising, Germany
| | - Wieland Steinchen
- Center for Synthetic Microbiology (SYNMIKRO) & Faculty of Chemistry, Philipps-University Marburg, Karl-von-Frisch-Straße 14, 35043 Marburg, Germany
| | - Timothy D Hoffmann
- Biotechnology of Natural Products, Technische Universität München, Liesel-Beckmann-Str. 1, 85354 Freising, Germany
| | - Chuankui Song
- State Key Laboratory of Tea Plant Biology and Utilization, International Joint Laboratory on Tea Chemistry and Health Effects, Anhui Agricultural University, 230036 Hefei, Anhui, P. R. China
| | - Zhiwei Zou
- Biotechnology of Natural Products, Technische Universität München, Liesel-Beckmann-Str. 1, 85354 Freising, Germany
| | - Thomas Hoffmann
- Biotechnology of Natural Products, Technische Universität München, Liesel-Beckmann-Str. 1, 85354 Freising, Germany
| | - Wilfried G Schwab
- Biotechnology of Natural Products, Technische Universität München, Liesel-Beckmann-Str. 1, 85354 Freising, Germany.
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15
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Sirirungruang S, Barnum CR, Tang SN, Shih PM. Plant glycosyltransferases for expanding bioactive glycoside diversity. Nat Prod Rep 2023. [PMID: 36853278 DOI: 10.1039/d2np00077f] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
Glycosylation is a successful strategy to alter the pharmacological properties of small molecules, and it has emerged as a unique approach to expand the chemical space of natural products that can be explored in drug discovery. Traditionally, most glycosylation events have been carried out chemically, often requiring many protection and deprotection steps to achieve a target molecule. Enzymatic glycosylation by glycosyltransferases could provide an alternative strategy for producing new glycosides. In particular, the glycosyltransferase family has greatly expanded in plants, representing a rich enzymatic resource to mine and expand the diversity of glycosides with novel bioactive properties. This article highlights previous and prospective uses for plant glycosyltransferases in generating bioactive glycosides and altering their pharmacological properties.
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Affiliation(s)
- Sasilada Sirirungruang
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA.,Feedstocks Division, Joint BioEnergy Institute, Emeryville, CA, USA.,Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.,Center for Biomolecular Structure, Function and Application, Suranaree University of Technology, Nakhon Ratchasima, Thailand
| | - Collin R Barnum
- Department of Plant Biology, University of California, Davis, CA, USA
| | - Sophia N Tang
- Feedstocks Division, Joint BioEnergy Institute, Emeryville, CA, USA.,Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.,Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | - Patrick M Shih
- Department of Plant and Microbial Biology, University of California, Berkeley, CA, USA.,Feedstocks Division, Joint BioEnergy Institute, Emeryville, CA, USA.,Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.,Innovative Genomics Institute, University of California, Berkeley, CA, USA
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16
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UDP-Glycosyltransferases in Edible Fungi: Function, Structure, and Catalytic Mechanism. FERMENTATION-BASEL 2023. [DOI: 10.3390/fermentation9020164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
UDP-glycosyltransferases (UGTs) are the most studied glycosyltransferases, and belong to large GT1 family performing the key roles in antibiotic synthesis, the development of bacterial glycosyltransferase inhibitors, and in animal inflammation. They transfer the glycosyl groups from nucleotide UDP-sugars (UDP-glucose, UDP-galactose, UDP-xylose, and UDP-rhamnose) to the acceptors including saccharides, proteins, lipids, and secondary metabolites. The present review summarized the recent of UDP-glycosyltransferases, including their structures, functions, and catalytic mechanism, especially in edible fungi. The future perspectives and new challenges were also summarized to understand of their structure–function relationships in the future. The outputs in this field could provide a reference to recognize function, structure, and catalytic mechanism of UDP-glycosyltransferases for understanding the biosynthesis pathways of secondary metabolites, such as hydrocarbons, monoterpenes, sesquiterpene, and polysaccharides in edible fungi.
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17
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Porter J, Lima MA, Pongener I, Miller GJ. Synthesis of 4-thio-d-glucopyranose and interconversion to 4-thio-d-glucofuranose. Carbohydr Res 2023; 524:108759. [PMID: 36746019 DOI: 10.1016/j.carres.2023.108759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 01/12/2023] [Accepted: 01/23/2023] [Indexed: 01/26/2023]
Abstract
Sulfur containing glycosides offer an exciting prospect for inclusion within noncanonical glycan sequences, particularly as enabling probes for chemical glycobiology and for carbohydrate-based therapeutic development. In this context, we required access to 4-thio-d-glucopyranose and sought its chemical synthesis. Unable to isolate this material in homogenous form, we observed instead a thermodynamic preference for interconversion of the pyranose to 4-thio-d-glucofuranose. Accordingly, we present an improved method to access both bis(4-thio-d-glucopyranoside)-4,4'-disulfide and 4-thio-d-glucofuranose from a single precursor, demonstrating that the latter compound can be accessed from the former using a dithiothreitol controlled reduction of the disulfide. The dithiothreitol-mediated interconversion between pyranose (monomer and disulfide) and furanose forms for this thiosugar is monitored by 1H NMR spectroscopy over a 24-h period. Access to these materials will support accessing sulfur-containing mimetics of glucose and derivatives therefrom, such as sugar nucleotides.
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Affiliation(s)
- Jack Porter
- Centre for Glycosciences, Keele University, Keele, Staffordshire, ST5 5BG, UK; Lennard-Jones Laboratory, School of Chemical and Physical Sciences, Keele University, Keele, Staffordshire, ST5 5BG, UK
| | - Marcelo A Lima
- Centre for Glycosciences, Keele University, Keele, Staffordshire, ST5 5BG, UK; School of Life Sciences, Keele University, Keele, Staffordshire, ST5 5BG, UK
| | - Imlirenla Pongener
- Centre for Glycosciences, Keele University, Keele, Staffordshire, ST5 5BG, UK; Lennard-Jones Laboratory, School of Chemical and Physical Sciences, Keele University, Keele, Staffordshire, ST5 5BG, UK.
| | - Gavin J Miller
- Centre for Glycosciences, Keele University, Keele, Staffordshire, ST5 5BG, UK; Lennard-Jones Laboratory, School of Chemical and Physical Sciences, Keele University, Keele, Staffordshire, ST5 5BG, UK.
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18
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Ouadhi S, López DMV, Mohideen FI, Kwan DH. Engineering the enzyme toolbox to tailor glycosylation in small molecule natural products and protein biologics. Protein Eng Des Sel 2023; 36:gzac010. [PMID: 36444941 DOI: 10.1093/protein/gzac010] [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: 07/11/2022] [Revised: 07/11/2022] [Accepted: 10/04/2022] [Indexed: 12/03/2022] Open
Abstract
Many glycosylated small molecule natural products and glycoprotein biologics are important in a broad range of therapeutic and industrial applications. The sugar moieties that decorate these compounds often show a profound impact on their biological functions, thus biocatalytic methods for controlling their glycosylation are valuable. Enzymes from nature are useful tools to tailor bioproduct glycosylation but these sometimes have limitations in their catalytic efficiency, substrate specificity, regiospecificity, stereospecificity, or stability. Enzyme engineering strategies such as directed evolution or semi-rational and rational design have addressed some of the challenges presented by these limitations. In this review, we highlight some of the recent research on engineering enzymes to tailor the glycosylation of small molecule natural products (including alkaloids, terpenoids, polyketides, and peptides), as well as the glycosylation of protein biologics (including hormones, enzyme-replacement therapies, enzyme inhibitors, vaccines, and antibodies).
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Affiliation(s)
- Sara Ouadhi
- Centre for Applied Synthetic Biology, Concordia University, Montreal, QC H4B 2A6, Canada
- PROTEO, Quebec Network for Research on Protein Function, Structure, and Engineering, Quebec City, QC G1V 0A6, Canada
| | - Dulce María Valdez López
- Centre for Applied Synthetic Biology, Concordia University, Montreal, QC H4B 2A6, Canada
- PROTEO, Quebec Network for Research on Protein Function, Structure, and Engineering, Quebec City, QC G1V 0A6, Canada
| | - F Ifthiha Mohideen
- Department of Chemistry, University of Alberta, Edmonton, AB T6G 2G2, Canada
| | - David H Kwan
- Centre for Applied Synthetic Biology, Concordia University, Montreal, QC H4B 2A6, Canada
- PROTEO, Quebec Network for Research on Protein Function, Structure, and Engineering, Quebec City, QC G1V 0A6, Canada
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19
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Structural insights into mechanism and specificity of the plant protein O-fucosyltransferase SPINDLY. Nat Commun 2022; 13:7424. [PMID: 36456586 PMCID: PMC9715652 DOI: 10.1038/s41467-022-35234-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 11/22/2022] [Indexed: 12/04/2022] Open
Abstract
Arabidopsis glycosyltransferase family 41 (GT41) protein SPINDLY (SPY) plays pleiotropic roles in plant development. Despite the amino acid sequence is similar to human O-GlcNAc transferase, Arabidopsis SPY has been identified as a novel nucleocytoplasmic protein O-fucosyltransferase. SPY-like proteins extensively exist in diverse organisms, indicating that O-fucosylation by SPY is a common way to regulate intracellular protein functions. However, the details of how SPY recognizes and glycosylates substrates are unknown. Here, we present a crystal structure of Arabidopsis SPY/GDP complex at 2.85 Å resolution. SPY adopts a head-to-tail dimer. Strikingly, the conformation of a 'catalytic SPY'/GDP/'substrate SPY' complex formed by two symmetry-related SPY dimers is captured in the crystal lattice. The structure together with mutagenesis and enzymatic data demonstrate SPY can fucosylate itself and SPY's self-fucosylation region negatively regulates its enzyme activity, reveal SPY's substrate recognition and enzyme mechanism, and provide insights into the glycan donor substrate selection in GT41 proteins.
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20
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Franceus J, Lormans J, Desmet T. Building mutational bridges between carbohydrate-active enzymes. Curr Opin Biotechnol 2022; 78:102804. [PMID: 36156353 DOI: 10.1016/j.copbio.2022.102804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 08/12/2022] [Accepted: 08/24/2022] [Indexed: 12/14/2022]
Abstract
The commercial value of specialty carbohydrates and glycosylated compounds has sparked considerable interest in the synthetic potential of carbohydrate-active enzymes (CAZymes). Protein engineering methods have proven to be highly successful in expanding the range of glycosylation reactions that these enzymes can perform efficiently and cost-effectively. The past few years have witnessed meaningful progress in this area, largely due to a sharper focus on the understanding of structure-function relationships and mechanistic intricacies. Here, we summarize recent studies that demonstrate how protein engineers have become much better at traversing the fitness landscape of CAZymes through mutational bridges that connect the different activity types.
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Affiliation(s)
- Jorick Franceus
- Centre for Synthetic Biology (CSB), Department of Biotechnology, Ghent University, Coupure Links 653, 9000 Ghent, Belgium
| | - Jolien Lormans
- Centre for Synthetic Biology (CSB), Department of Biotechnology, Ghent University, Coupure Links 653, 9000 Ghent, Belgium
| | - Tom Desmet
- Centre for Synthetic Biology (CSB), Department of Biotechnology, Ghent University, Coupure Links 653, 9000 Ghent, Belgium.
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21
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Genome Wide Analysis of Family-1 UDP Glycosyltransferases in Populus trichocarpa Specifies Abiotic Stress Responsive Glycosylation Mechanisms. Genes (Basel) 2022; 13:genes13091640. [PMID: 36140806 PMCID: PMC9498546 DOI: 10.3390/genes13091640] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 08/22/2022] [Accepted: 08/25/2022] [Indexed: 11/21/2022] Open
Abstract
Populus trichocarpa (Black cottonwood) is a dominant timber-yielding tree that has become a notable model plant for genome-level insights in forest trees. The efficient transport and solubility of various glycoside-associated compounds is linked to Family-1 UDP-glycosyltransferase (EC 2.4.1.x; UGTs) enzymes. These glycosyltransferase enzymes play a vital role in diverse plant functions, such as regulation of hormonal homeostasis, growth and development (seed, flower, fiber, root, etc.), xenobiotic detoxification, stress response (salt, drought, and oxidative), and biosynthesis of secondary metabolites. Here, we report a genome-wide analysis of the P. trichocarpa genome that identified 191 putative UGTs distributed across all chromosomes (with the exception of chromosome 20) based on 44 conserved plant secondary product glycosyltransferase (PSPG) motif amino acid sequences. Phylogenetic analysis of the 191 Populus UGTs together with 22 referenced UGTs from Arabidopsis and maize clustered the putative UGTs into 16 major groups (A–P). Whole-genome duplication events were the dominant pattern of duplication among UGTs in Populus. A well-conserved intron insertion was detected in most intron-containing UGTs across eight examined eudicots, including Populus. Most of the UGT genes were found preferentially expressed in leaf and root tissues in general. The regulation of putative UGT expression in response to drought, salt and heat stress was observed based on microarray and available RNA sequencing datasets. Up- and down-regulated UGT expression models were designed, based on transcripts per kilobase million values, confirmed their maximally varied expression under drought, salt and heat stresses. Co-expression networking of putative UGTs indicated their maximum co-expression with cytochrome P450 genes involved in triterpenoid biosynthesis. Our results provide an important resource for the identification of functional UGT genes to manipulate abiotic stress responsive glycosylation in Populus.
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22
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Del Giudice R, Putkaradze N, dos Santos BM, Hansen CC, Crocoll C, Motawia MS, Fredslund F, Laursen T, Welner DH. Structure-guided engineering of key amino acids in UGT85B1 controlling substrate and stereo-specificity in aromatic cyanogenic glucoside biosynthesis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 111:1539-1549. [PMID: 35819080 PMCID: PMC9545476 DOI: 10.1111/tpj.15904] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Revised: 07/05/2022] [Accepted: 07/07/2022] [Indexed: 06/15/2023]
Abstract
Cyanogenic glucosides are important defense molecules in plants with useful biological activities in animals. Their last biosynthetic step consists of a glycosylation reaction that confers stability and increases structural diversity and is catalyzed by the UDP-dependent glycosyltransferases (UGTs) of glycosyltransferase family 1. These versatile enzymes have large and varied substrate scopes, and the structure-function relationships controlling scope and specificity remain poorly understood. Here, we report substrate-bound crystal structures and rational engineering of substrate and stereo-specificities of UGT85B1 from Sorghum bicolor involved in biosynthesis of the cyanogenic glucoside dhurrin. Substrate specificity was shifted from the natural substrate (S)-p-hydroxymandelonitrile to (S)-mandelonitrile by combining a mutation to abolish hydrogen bonding to the p-hydroxyl group with a mutation to provide steric hindrance at the p-hydroxyl group binding site (V132A/Q225W). Further, stereo-specificity was shifted from (S) to (R) by substituting four rationally chosen residues within 6 Å of the nitrile group (M312T/A313T/H408F/G409A). These activities were compared to two other UGTs involved in the biosynthesis of aromatic cyanogenic glucosides in Prunus dulcis (almond) and Eucalyptus cladocalyx. Together, these studies enabled us to pinpoint factors that drive substrate and stereo-specificities in the cyanogenic glucoside biosynthetic UGTs. The structure-guided engineering of the functional properties of UGT85B1 enhances our understanding of the evolution of UGTs involved in the biosynthesis of cyanogenic glucosides and will enable future engineering efforts towards new biotechnological applications.
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Affiliation(s)
- Rita Del Giudice
- Plant Biochemistry, Department of Plant and Environmental SciencesUniversity of CopenhagenThorvaldsensvej 40DK‐1871CopenhagenDenmark
| | - Natalia Putkaradze
- The Novo Nordisk Foundation Center for BiosustainabilityTechnical University of DenmarkKemitorvet 220DK‐2800Kgs. LyngbyDenmark
| | - Bruna Marques dos Santos
- Plant Biochemistry, Department of Plant and Environmental SciencesUniversity of CopenhagenThorvaldsensvej 40DK‐1871CopenhagenDenmark
| | - Cecilie Cetti Hansen
- Plant Biochemistry, Department of Plant and Environmental SciencesUniversity of CopenhagenThorvaldsensvej 40DK‐1871CopenhagenDenmark
| | - Christoph Crocoll
- DynaMo Center, Molecular Plant Biology, Department of Plant and Environmental SciencesUniversity of CopenhagenThorvaldsensvej 40DK‐1871CopenhagenDenmark
| | - Mohammed Saddik Motawia
- Plant Biochemistry, Department of Plant and Environmental SciencesUniversity of CopenhagenThorvaldsensvej 40DK‐1871CopenhagenDenmark
| | - Folmer Fredslund
- The Novo Nordisk Foundation Center for BiosustainabilityTechnical University of DenmarkKemitorvet 220DK‐2800Kgs. LyngbyDenmark
| | - Tomas Laursen
- Plant Biochemistry, Department of Plant and Environmental SciencesUniversity of CopenhagenThorvaldsensvej 40DK‐1871CopenhagenDenmark
| | - Ditte Hededam Welner
- The Novo Nordisk Foundation Center for BiosustainabilityTechnical University of DenmarkKemitorvet 220DK‐2800Kgs. LyngbyDenmark
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23
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Subedi P, Kim MS, Lee JH, Park JK, Oh TJ. Insight into glucocorticoids glucosylation by glucosyltransferase: A combined experimental and in-silico approach. Biophys Chem 2022; 289:106875. [PMID: 35987098 DOI: 10.1016/j.bpc.2022.106875] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Revised: 08/06/2022] [Accepted: 08/06/2022] [Indexed: 11/28/2022]
Abstract
Glucosyltransferases catalyze the glucosidic bond formation by transferring a glucose molecule from an activated sugar donor to an acceptor substrate. Glucocorticoids (GCs) are adrenal-derived steroid hormones most widely used for anti-inflammatory treatments. In this study, we biotransformed two selected GCs, cortisone and prednisone, into their O-glucoside derivatives using a versatile UDP-glycosyltransferase UGT-1. Complete structural assignment of glucosylated products revealed that the bioconversion by regio-selective glucosylation of cortisone and prednisone produced cortisone 21-glucoside and prednisone 21-glucoside, respectively. We also combined molecular dynamics (MD) simulation to study the binding feature and mechanism of glucosylation. MD simulation studies showed the formation of a stable complex between protein, glucose donor, and substrate, stabilized by hydrogen bonds. Overall, we were able to provide explanations for the experimentally observed selectivity for glucosylation by integrating experimental and computational techniques.
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Affiliation(s)
- Pradeep Subedi
- Department of Life Science and Biochemical Engineering, Sunmoon University, 70 Sunmoon-ro 221, Tangjeong-myeon, Asan-si, Chungnam 31460, Republic of Korea
| | - Min-Su Kim
- Department of Life Science and Biochemical Engineering, Sunmoon University, 70 Sunmoon-ro 221, Tangjeong-myeon, Asan-si, Chungnam 31460, Republic of Korea
| | - Joo-Ho Lee
- Genome-based BioIT Convergence Institute, 70 Sunmoon-ro 221, Tangjeong-myeon, Asan-si, Chungnam 31460, Republic of Korea; Department of BT-Convergent Pharmaceutical Engineering, Sunmoon University, 70 Sunmoon-ro 221, Tangjeong-myeon, Asan-si, Chungnam 31460, Republic of Korea
| | - Jong Kook Park
- Department of Biomedical Science and Research Institute for Bioscience & Biotechnology, Hallym University, 1 Hallymdaehak-gil, Chuncheon, Gangwon-do 24252, Republic of Korea
| | - Tae-Jin Oh
- Department of Life Science and Biochemical Engineering, Sunmoon University, 70 Sunmoon-ro 221, Tangjeong-myeon, Asan-si, Chungnam 31460, Republic of Korea; Genome-based BioIT Convergence Institute, 70 Sunmoon-ro 221, Tangjeong-myeon, Asan-si, Chungnam 31460, Republic of Korea; Department of BT-Convergent Pharmaceutical Engineering, Sunmoon University, 70 Sunmoon-ro 221, Tangjeong-myeon, Asan-si, Chungnam 31460, Republic of Korea.
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24
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Neves RPP, Fernandes PA, Ramos MJ. Role of Enzyme and Active Site Conformational Dynamics in the Catalysis by α-Amylase Explored with QM/MM Molecular Dynamics. J Chem Inf Model 2022; 62:3638-3650. [PMID: 35880954 PMCID: PMC9778734 DOI: 10.1021/acs.jcim.2c00691] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
We assessed enzyme:substrate conformational dynamics and the rate-limiting glycosylation step of a human pancreatic α-amylase:maltopentose complex. Microsecond molecular dynamics simulations suggested that the distance of the catalytic Asp197 nucleophile to the anomeric carbon of the buried glucoside is responsible for most of the enzyme active site fluctuations and that both Asp197 and Asp300 interact the most with the buried glucoside unit. The buried glucoside binds either in a 4C1 chair or 2SO skew conformations, both of which can change to TS-like conformations characteristic of retaining glucosidases. Starting from four distinct enzyme:substrate complexes, umbrella sampling quantum mechanics/molecular mechanics simulations (converged within less than 1 kcal·mol-1 within a total simulation time of 1.6 ns) indicated that the reaction occurrs with a Gibbs barrier of 13.9 kcal·mol -1, in one asynchronous concerted step encompassing an acid-base reaction with Glu233 followed by a loose SN2-like nucleophilic substitution by the Asp197. The transition state is characterized by a 2H3 half-chair conformation of the buried glucoside that quickly changes to the E3 envelope conformation preceding the attack of the anomeric carbon by the Asp197 nucleophile. Thermodynamic analysis of the reaction supported that a water molecule tightly hydrogen bonded to the glycosidic oxygen of the substrate at the reactant state (∼1.6 Å) forms a short hydrogen bond with Glu233 at the transition state (∼1.7 Å) and lowers the Gibbs barrier in over 5 kcal·mol-1. The resulting Asp197-glycosyl was mostly found in the 4C1 conformation, although the more endergonic B3,O conformation was also observed. Altogether, the combination of short distances for the acid-base reaction with the Glu233 and for the nucleophilic attack by the Asp197 nucleophile and the availability of water within hydrogen bonding distance of the glycosidic oxygen provides a reliable criteria to identify reactive conformations of α-amylase complexes.
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25
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Teze D, Bidart GN, Welner DH. Family 1 glycosyltransferases (GT1, UGTs) are subject to dilution-induced inactivation and low chemo stability toward their own acceptor substrates. Front Mol Biosci 2022; 9:909659. [PMID: 35936788 PMCID: PMC9354691 DOI: 10.3389/fmolb.2022.909659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 06/28/2022] [Indexed: 11/13/2022] Open
Abstract
Glycosylation reactions are essential but challenging from a conventional chemistry standpoint. Conversely, they are biotechnologically feasible as glycosyltransferases can transfer sugar to an acceptor with perfect regio- and stereo-selectivity, quantitative yields, in a single reaction and under mild conditions. Low stability is often alleged to be a limitation to the biotechnological application of glycosyltransferases. Here we show that these enzymes are not necessarily intrinsically unstable, but that they present both dilution-induced inactivation and low chemostability towards their own acceptor substrates, and that these two phenomena are synergistic. We assessed 18 distinct GT1 enzymes against three unrelated acceptors (apigenin, resveratrol, and scopoletin—respectively a flavone, a stilbene, and a coumarin), resulting in a total of 54 enzymes: substrate pairs. For each pair, we varied catalyst and acceptor concentrations to obtain 16 different reaction conditions. Fifteen of the assayed enzymes (83%) displayed both low chemostability against at least one of the assayed acceptors at submillimolar concentrations, and dilution-induced inactivation. Furthermore, sensitivity to reaction conditions seems to be related to the thermal stability of the enzymes, the three unaffected enzymes having melting temperatures above 55°C, whereas the full enzyme panel ranged from 37.4 to 61.7°C. These results are important for GT1 understanding and engineering, as well as for discovery efforts and biotechnological use.
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Affiliation(s)
- David Teze
- *Correspondence: David Teze, ; Ditte Hededam Welner,
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26
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Recent developments in promiscuous enzymatic reactions for carbon-nitrogen bond formation. Bioorg Chem 2022; 127:106014. [PMID: 35841668 DOI: 10.1016/j.bioorg.2022.106014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 06/07/2022] [Accepted: 07/06/2022] [Indexed: 11/21/2022]
Abstract
Biocatalytic promiscuity is a new field of enzyme application in biochemistry, which has received much attention and has developed rapidly in recent years. The promiscuous biocatalysis has been promoted as a useful supplement to traditional strategy for the formation of C-heteroatom bonds. The generation of carbon-nitrogen (CN) bonds is an important issue in synthetic chemistry and is indispensable for the manufacturing of various pharmaceuticals and agrochemicals. Therefore, numerous efficient and reliable synthetic methods for the formation of CN bonds have been developed in recent years. Enzymatic CN bond forming reactions catalyzed by lipases, cytochrome P450 monooxygenases, glycosyltransferases, amine dehydrogenases, proteases, acylases, amylases and halohydrin dehalogenases are well established for synthetic purposes. This review introduces the recent progress in the construction of CN bonds using promiscuous enzymes.
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27
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Behr M, Speeckaert N, Kurze E, Morel O, Prévost M, Mol A, Mahamadou Adamou N, Baragé M, Renaut J, Schwab W, El Jaziri M, Baucher M. Leaf necrosis resulting from downregulation of poplar glycosyltransferase UGT72A2. TREE PHYSIOLOGY 2022; 42:1084-1099. [PMID: 34865151 DOI: 10.1093/treephys/tpab161] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 11/29/2021] [Indexed: 06/13/2023]
Abstract
Reactive species (RS) causing oxidative stress are unavoidable by-products of various plant metabolic processes, such as photosynthesis, respiration or photorespiration. In leaves, flavonoids scavenge RS produced during photosynthesis and protect plant cells against deleterious oxidative damages. Their biosynthesis and accumulation are therefore under tight regulation at the cellular level. Glycosylation has emerged as an essential biochemical reaction in the homeostasis of various specialized metabolites such as flavonoids. This article provides a functional characterization of the Populus tremula x P. alba (poplar) UGT72A2 coding for a UDP-glycosyltransferase that is localized in the chloroplasts. Compared with the wild type, transgenic poplar lines with decreased expression of UGT72A2 are characterized by reduced growth and oxidative damages in leaves, as evidenced by necrosis, higher content of glutathione and lipid peroxidation products as well as diminished soluble peroxidase activity and NADPH to NADP+ ratio under standard growing conditions. They furthermore display lower pools of phenolics, anthocyanins and total flavonoids but higher proanthocyanidins content. Promoter analysis revealed the presence of cis-elements involved in photomorphogenesis, chloroplast biogenesis and flavonoid biosynthesis. The UGT72A2 is regulated by the poplar MYB119, a transcription factor known to regulate the flavonoid biosynthesis pathway. Phylogenetic analysis and molecular docking suggest that UGT72A2 could glycosylate flavonoids; however, the actual substrate(s) was not consistently evidenced with either in vitro assays nor analyses of glycosylated products in leaves of transgenic poplar overexpressing or downregulated for UGT72A2. This article provides elements highlighting the importance of flavonoid glycosylation regarding protection against oxidative stress in poplar leaves and raises new questions about the link between this biochemical reaction and regulation of the redox homeostasis system.
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Affiliation(s)
- Marc Behr
- Laboratory of Plant Biotechnology, Université libre de Bruxelles, 12 rue des Profs Jeener et Brachet, Gosselies 6041, Belgium
| | - Nathanael Speeckaert
- Laboratory of Plant Biotechnology, Université libre de Bruxelles, 12 rue des Profs Jeener et Brachet, Gosselies 6041, Belgium
| | - Elisabeth Kurze
- Biotechnology of Natural Products, Technische Universität München, 85354 Freising, Germany
| | - Oriane Morel
- Laboratory of Plant Biotechnology, Université libre de Bruxelles, 12 rue des Profs Jeener et Brachet, Gosselies 6041, Belgium
| | - Martine Prévost
- Unité de recherche Structure et Fonction des Membranes Biologiques, Université libre de Bruxelles, Bruxelles, Belgium
| | - Adeline Mol
- Laboratory of Plant Biotechnology, Université libre de Bruxelles, 12 rue des Profs Jeener et Brachet, Gosselies 6041, Belgium
| | - Nassirou Mahamadou Adamou
- Laboratory of Plant Biotechnology, Université libre de Bruxelles, 12 rue des Profs Jeener et Brachet, Gosselies 6041, Belgium
- Laboratoire de Biotechnologie Végétale et Amélioration des Plantes (LABAP), Université Abdou Moumouni de Niamey, Niamey, Niger
| | - Moussa Baragé
- Laboratoire de Biotechnologie Végétale et Amélioration des Plantes (LABAP), Université Abdou Moumouni de Niamey, Niamey, Niger
| | - Jenny Renaut
- Luxembourg Institute of Science and Technology, 4422 Belvaux, Luxembourg
| | - Wilfried Schwab
- Biotechnology of Natural Products, Technische Universität München, 85354 Freising, Germany
| | - Mondher El Jaziri
- Laboratory of Plant Biotechnology, Université libre de Bruxelles, 12 rue des Profs Jeener et Brachet, Gosselies 6041, Belgium
| | - Marie Baucher
- Laboratory of Plant Biotechnology, Université libre de Bruxelles, 12 rue des Profs Jeener et Brachet, Gosselies 6041, Belgium
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28
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Bidart G, Putkaradze N, Fredslund F, Kjeldsen C, Ruiz AG, Duus JØ, Teze D, Welner DH. Family 1 Glycosyltransferase UGT706F8 from Zea mays Selectively Catalyzes the Synthesis of Silibinin 7- O-β-d-Glucoside. ACS SUSTAINABLE CHEMISTRY & ENGINEERING 2022; 10:5078-5083. [PMID: 35493695 PMCID: PMC9045260 DOI: 10.1021/acssuschemeng.1c07593] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 03/24/2022] [Indexed: 05/07/2023]
Abstract
Regioselective glycosylation is a chemical challenge, leading to multistep syntheses with protecting group manipulations, ultimately resulting in poor atom economy and compromised sustainability. Enzymes allow eco-friendly and regioselective bond formation with fully deprotected substrates in a single reaction. For the selective glucosylation of silibinin, a pharmaceutical challenged with low solubility, enzyme engineering has previously been employed, but the resulting yields and k cat were limited, prohibiting the application of the engineered catalyst. Here, we identified a naturally regioselective silibinin glucosyltransferase, UGT706F8, a family 1 glycosyltransferase from Zea mays. It selectively and efficiently (k cat = 2.1 ± 0.1 s-1; K M = 36.9 ± 5.2 μM; TTN = 768 ± 22) catalyzes the quantitative synthesis of silibinin 7-O-β-d-glucoside. We solved the crystal structure of UGT706F8 and investigated the molecular determinants of regioselective silibinin glucosylation. UGT706F8 was the only regioselective enzyme among 18 glycosyltransferases found to be active on silibinin. We found the temperature optimum of UGT706F8 to be 34 °C and the pH optimum to be 7-8. Our results indicate that UGT706F8 is an efficient silibinin glycosyltransferase that enables biocatalytic production of silbinin 7-O-β-d-glucoside.
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Affiliation(s)
- Gonzalo
N. Bidart
- The
Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark
| | - Natalia Putkaradze
- The
Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark
| | - Folmer Fredslund
- The
Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark
| | - Christian Kjeldsen
- DTU
Chemistry, Technical University of Denmark, DK-2800 Kongens
Lyngby, Denmark
| | - Ander Garralda Ruiz
- The
Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark
| | - Jens Ø. Duus
- DTU
Chemistry, Technical University of Denmark, DK-2800 Kongens
Lyngby, Denmark
| | - David Teze
- The
Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark
- (D. Teze)
| | - Ditte H. Welner
- The
Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark
- (D. H. Welner)
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29
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Derat E, Kamerlin SCL. Computational Advances in Protein Engineering and Enzyme Design. J Phys Chem B 2022; 126:2449-2451. [PMID: 35387452 DOI: 10.1021/acs.jpcb.2c01198] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Etienne Derat
- Institut Parisien de Chimie Moléculaire, UMR 8232 CNRS, Sorbonne Université, 75005 Paris, France
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30
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Dauda WP, Shanmugam V, Tyagi A, Solanke AU, Kumar V, Krishnan SG, Bashyal BM, Aggarwal R. Genome-Wide Identification and Characterisation of Cytokinin-O-Glucosyltransferase (CGT) Genes of Rice Specific to Potential Pathogens. PLANTS (BASEL, SWITZERLAND) 2022; 11:plants11070917. [PMID: 35406897 PMCID: PMC9002877 DOI: 10.3390/plants11070917] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 03/25/2022] [Accepted: 03/25/2022] [Indexed: 05/12/2023]
Abstract
Cytokinin glucosyltransferases (CGTs) are key enzymes of plants for regulating the level and function of cytokinins. In a genomic identification of rice CGTs, 41 genes with the plant secondary product glycosyltransferases (PSPG) motif of 44-amino-acid consensus sequence characteristic of plant uridine diphosphate (UDP)-glycosyltransferases (UGTs) were identified. In-silico physicochemical characterisation revealed that, though the CGTs belong to the same subfamily, they display varying molecular weights, ranging from 19.6 kDa to 59.7 kDa. The proteins were primarily acidic (87.8%) and hydrophilic (58.6%) and were observed to be distributed in the plastids (16), plasma membrane (13), mitochondria (5), and cytosol (4). Phylogenetic analysis of the CGTs revealed that their evolutionary relatedness ranged from 70-100%, and they aligned themselves into two major clusters. In a comprehensive analysis of the available transcriptomics data of rice samples representing different growth stages only the CGT, Os04g25440.1 was significantly expressed at the vegetative stage, whereas 16 other genes were highly expressed only at the reproductive growth stage. On the contrary, six genes, LOC_Os07g30610.1, LOC_Os04g25440.1, LOC_Os07g30620.1, LOC_Os04g25490.1, LOC_Os04g37820.1, and LOC_Os04g25800.1, were significantly upregulated in rice plants inoculated with Rhizoctonia solani (RS), Xoo (Xanthomonas oryzae pv. oryzae) and Mor (Magnaporthe oryzae). In a qRT-PCR analysis of rice sheath tissue susceptible to Rhizoctonia solani, Mor, and Xoo pathogens, compared to the sterile distilled water control, at 24 h post-infection only two genes displayed significant upregulation in response to all the three pathogens: LOC_Os07g30620.1 and LOC_Os04g25820.1. On the other hand, the expression of genes LOC_Os07g30610.1, LOC_Os04g25440, LOC_Os04g25490, and LOC_Os04g25800 were observed to be pathogen-specific. These genes were identified as the candidate-responsive CGT genes and could serve as potential susceptibility genes for facilitating pathogen infection.
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Affiliation(s)
- Wadzani Palnam Dauda
- ICAR-Indian Agricultural Research Institute, New Delhi 110012, India; (W.P.D.); (A.T.); (S.G.K.); (B.M.B.); (R.A.)
- Crop Science Unit, Department of Agronomy, Federal University, Gashua 1005, Nigeria
| | - Veerubommu Shanmugam
- ICAR-Indian Agricultural Research Institute, New Delhi 110012, India; (W.P.D.); (A.T.); (S.G.K.); (B.M.B.); (R.A.)
- Correspondence:
| | - Aditya Tyagi
- ICAR-Indian Agricultural Research Institute, New Delhi 110012, India; (W.P.D.); (A.T.); (S.G.K.); (B.M.B.); (R.A.)
| | - Amolkumar U. Solanke
- ICAR-National Institute for Plant Biotechnology, New Delhi 110012, India; (A.U.S.); (V.K.)
| | - Vishesh Kumar
- ICAR-National Institute for Plant Biotechnology, New Delhi 110012, India; (A.U.S.); (V.K.)
| | - Subbaiyan Gopala Krishnan
- ICAR-Indian Agricultural Research Institute, New Delhi 110012, India; (W.P.D.); (A.T.); (S.G.K.); (B.M.B.); (R.A.)
| | - Bishnu Maya Bashyal
- ICAR-Indian Agricultural Research Institute, New Delhi 110012, India; (W.P.D.); (A.T.); (S.G.K.); (B.M.B.); (R.A.)
| | - Rashmi Aggarwal
- ICAR-Indian Agricultural Research Institute, New Delhi 110012, India; (W.P.D.); (A.T.); (S.G.K.); (B.M.B.); (R.A.)
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31
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Coines J, Cuxart I, Teze D, Rovira C. Computer Simulation to Rationalize “Rational” Engineering of Glycoside Hydrolases and Glycosyltransferases. J Phys Chem B 2022; 126:802-812. [PMID: 35073079 PMCID: PMC8819650 DOI: 10.1021/acs.jpcb.1c09536] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
![]()
Glycoside hydrolases
and glycosyltransferases are the main classes
of enzymes that synthesize and degrade carbohydrates, molecules essential
to life that are a challenge for classical chemistry. As such, considerable
efforts have been made to engineer these enzymes and make them pliable
to human needs, ranging from directed evolution to rational design,
including mechanism engineering. Such endeavors fall short and are
unreported in numerous cases, while even success is a necessary but
not sufficient proof that the chemical rationale behind the design
is correct. Here we review some of the recent work in CAZyme mechanism
engineering, showing that computational simulations are instrumental
to rationalize experimental data, providing mechanistic insight into
how native and engineered CAZymes catalyze chemical reactions. We
illustrate this with two recent studies in which (i) a glycoside hydrolase
is converted into a glycoside phosphorylase and (ii) substrate specificity
of a glycosyltransferase is engineered toward forming O-, N-, or S-glycosidic bonds.
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Affiliation(s)
- Joan Coines
- Departament de Química Inorgànica i Orgànica and Institut de Química Teòrica i Computacional (IQTCUB), Universitat de Barcelona, Barcelona 08028, Spain
| | - Irene Cuxart
- Departament de Química Inorgànica i Orgànica and Institut de Química Teòrica i Computacional (IQTCUB), Universitat de Barcelona, Barcelona 08028, Spain
| | - David Teze
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kgs. Lyngby 2800, Denmark
| | - Carme Rovira
- Departament de Química Inorgànica i Orgànica and Institut de Química Teòrica i Computacional (IQTCUB), Universitat de Barcelona, Barcelona 08028, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Passeig Lluís Companys 23, Barcelona 08010, Spain
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32
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Ospina F, Schülke KH, Hammer SC. Biocatalytic Alkylation Chemistry: Building Molecular Complexity with High Selectivity. Chempluschem 2021; 87:e202100454. [PMID: 34821073 DOI: 10.1002/cplu.202100454] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Revised: 11/05/2021] [Indexed: 12/28/2022]
Abstract
Biocatalysis has traditionally been viewed as a field that primarily enables access to chiral centers. This includes the synthesis of chiral alcohols, amines and carbonyl compounds, often through functional group interconversion via hydrolytic or oxidation-reduction reactions. This limitation is partly being overcome by the design and evolution of new enzymes. Here, we provide an overview of a recently thriving research field that we summarize as biocatalytic alkylation chemistry. In the past 3-4 years, numerous new enzymes have been developed that catalyze sp3 C-C/N/O/S bond formations. These enzymes utilize different mechanisms to generate molecular complexity by coupling simple fragments with high activity and selectivity. In many cases, the engineered enzymes perform reactions that are difficult or impossible to achieve with current small-molecule catalysts such as organocatalysts and transition-metal complexes. This review further highlights that the design of new enzyme function is particularly successful when off-the-shelf synthetic reagents are utilized to access non-natural reactive intermediates. This underscores how biocatalysis is gradually moving to a field that build molecules through selective bond forming reactions.
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Affiliation(s)
- Felipe Ospina
- Faculty of Chemistry, Bielefeld University, Universitätsstraße 25, 33615, Bielefeld, Germany
| | - Kai H Schülke
- Faculty of Chemistry, Bielefeld University, Universitätsstraße 25, 33615, Bielefeld, Germany
| | - Stephan C Hammer
- Faculty of Chemistry, Bielefeld University, Universitätsstraße 25, 33615, Bielefeld, Germany
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33
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Kurze E, Wüst M, Liao J, McGraphery K, Hoffmann T, Song C, Schwab W. Structure-function relationship of terpenoid glycosyltransferases from plants. Nat Prod Rep 2021; 39:389-409. [PMID: 34486004 DOI: 10.1039/d1np00038a] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Covering: up to 2021Terpenoids are physiologically active substances that are of great importance to humans. Their physicochemical properties are modified by glycosylation, in terms of polarity, volatility, solubility and reactivity, and their bioactivities are altered accordingly. Significant scientific progress has been made in the functional study of glycosylated terpenes and numerous plant enzymes involved in regio- and enantioselective glycosylation have been characterized, a reaction that remains chemically challenging. Crucial clues to the mechanism of terpenoid glycosylation were recently provided by the first crystal structures of a diterpene glycosyltransferase UGT76G1. Here, we review biochemically characterized terpenoid glycosyltransferases, compare their functions and primary structures, discuss their acceptor and donor substrate tolerance and product specificity, and elaborate features of the 3D structures of the first terpenoid glycosyltransferases from plants.
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Affiliation(s)
- Elisabeth Kurze
- Biotechnology of Natural Products, TUM School of Life Sciences, Technische Universität München, Liesel-Beckmann-Str. 1, 85354 Freising, Germany.
| | - Matthias Wüst
- Chair of Food Chemistry, Institute of Nutritional and Food Sciences, University of Bonn, Endenicher Allee 19C, 53115 Bonn, Germany.
| | - Jieren Liao
- Biotechnology of Natural Products, TUM School of Life Sciences, Technische Universität München, Liesel-Beckmann-Str. 1, 85354 Freising, Germany.
| | - Kate McGraphery
- Biotechnology of Natural Products, TUM School of Life Sciences, Technische Universität München, Liesel-Beckmann-Str. 1, 85354 Freising, Germany.
| | - Thomas Hoffmann
- Biotechnology of Natural Products, TUM School of Life Sciences, Technische Universität München, Liesel-Beckmann-Str. 1, 85354 Freising, Germany.
| | - Chuankui Song
- State Key Laboratory of Tea Plant Biology and Utilization, International Joint Laboratory on Tea Chemistry and Health Effects, Anhui Agricultural University Hefei, Anhui 230036, People's Republic of China.
| | - Wilfried Schwab
- Biotechnology of Natural Products, TUM School of Life Sciences, Technische Universität München, Liesel-Beckmann-Str. 1, 85354 Freising, Germany. .,State Key Laboratory of Tea Plant Biology and Utilization, International Joint Laboratory on Tea Chemistry and Health Effects, Anhui Agricultural University Hefei, Anhui 230036, People's Republic of China.
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Piniello B, Lira-Navarrete E, Takeuchi H, Takeuchi M, Haltiwanger RS, Hurtado-Guerrero R, Rovira C. Asparagine Tautomerization in Glycosyltransferase Catalysis. The Molecular Mechanism of Protein O-Fucosyltransferase 1. ACS Catal 2021; 11:9926-9932. [PMID: 34868727 PMCID: PMC8631701 DOI: 10.1021/acscatal.1c01785] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 07/19/2021] [Indexed: 12/12/2022]
Abstract
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O-glycosylation is a post-translational protein
modification essential to life. One of the enzymes involved in this
process is protein O-fucosyltransferase 1 (POFUT1),
which fucosylates threonine or serine residues within a specific sequence
context of epidermal growth factor-like domains (EGF-LD). Unlike most
inverting glycosyltransferases, POFUT1 lacks a basic residue in the
active site that could act as a catalytic base to deprotonate the
Thr/Ser residue of the EGF-LD acceptor during the chemical reaction.
Using quantum mechanics/molecular mechanics (QM/MM) methods on recent
crystal structures, as well as mutagenesis experiments, we uncover
the enzyme catalytic mechanism, revealing that it involves proton
shuttling through an active site asparagine, conserved among species,
which undergoes tautomerization. This mechanism is consistent with
experimental kinetic analysis of Caenorhabditis elegans POFUT1 Asn43 mutants, which ablate enzyme activity even if mutated
to Asp, the canonical catalytic base in inverting glycosyltransferases.
These results will aid inhibitor development for Notch-associated O-glycosylation disorders.
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Affiliation(s)
- Beatriz Piniello
- Departament de Química Inorgànica i Orgànica (Secció de Química Orgànica) and Institut de Química Teòrica i Computacional (IQTCUB), Universitat de Barcelona, Martí i Franquès 1, 08028 Barcelona, Spain
| | - Erandi Lira-Navarrete
- Institute of Biocomputation and Physics of Complex Systems (BIFI), University of Zaragoza, Mariano Esquillor s/n, Campus Rio Ebro, Edificio I+D, 50018 Zaragoza, Spain
| | - Hideyuki Takeuchi
- Department of Biochemistry and Molecular Biology, Complex Carbohydrate Research Center, The University of Georgia, Athens, Georgia 30602, United States
| | - Megumi Takeuchi
- Department of Biochemistry and Molecular Biology, Complex Carbohydrate Research Center, The University of Georgia, Athens, Georgia 30602, United States
| | - Robert S. Haltiwanger
- Department of Biochemistry and Molecular Biology, Complex Carbohydrate Research Center, The University of Georgia, Athens, Georgia 30602, United States
| | - Ramón Hurtado-Guerrero
- Institute of Biocomputation and Physics of Complex Systems (BIFI), University of Zaragoza, Mariano Esquillor s/n, Campus Rio Ebro, Edificio I+D, 50018 Zaragoza, Spain
- Fundación ARAID, 50018 Zaragoza, Spain
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, University of Copenhagen, 1017 Copenhagen, Denmark
| | - Carme Rovira
- Departament de Química Inorgànica i Orgànica (Secció de Química Orgànica) and Institut de Química Teòrica i Computacional (IQTCUB), Universitat de Barcelona, Martí i Franquès 1, 08028 Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Passeig Lluís Companys 23, 08010 Barcelona, Spain
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35
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Mendoza F, Jaña GA. The inverting mechanism of the metal ion-independent LanGT2: the first step to understand the glycosylation of natural product antibiotic precursors through QM/MM simulations. Org Biomol Chem 2021; 19:5888-5898. [PMID: 34132308 DOI: 10.1039/d1ob00544h] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Glycosyltransferases (GTs) from the GT1 family are responsible for the glycosylation of various important organic structures such as terpenes, steroids and peptide antibiotics, making it one of the most intensely studied families of GTs. The target of our study, LanGT2, is a member of the GT1 family that uses an inverting mechanism for transferring olivose from TDP-olivose, the donor substrate, to the natural product tetrangulol (Tet), the precursor of the antibiotic landomycin A. X-ray crystallography in conjunction with mutagenesis experiments has revealed the catalytic significance of 3 amino acids (Ser10, Ser219 and Asp137), suggesting Asp137 as the base catalyst. In the absence of X-ray structures that include the acceptor substrate Tet, in silico experiments and MD simulations that have modeled ternary complexes propose that Asp137 could recruit a water molecule to facilitate the nucleophilic activation of Tet, since the distance between Asp137 and the nucleophile is too long to directly deprotonate the nucleophilic moiety. So far, there is no computational evidence regarding the precise mechanism by which LanGT2 catalyzes the transfer of olivose, which raises questions such as: is a water-assisted mechanism possible? and how does this metal ion-independent GT stabilize the growing negative charge of the diphosphate leaving group? In this work, the QM/MM approach was used to unravel the catalytic mechanism of LanGT2, and to identify the role of crucial catalytic amino acids at a molecular level. Our calculations show that the minimum energy path (MEP) describes an SN2-like mechanism, identifying an oxocarbenium ion-like TS in which the olivosyl moiety adopts a 4H3 conformation. Interactions established between the diphosphate group of TDP and Ser10, Ser219, Arg220 and His283 are key to stabilize the development of charge on the leaving group. Our work also suggests that a water-mediated proton transfer mechanism is feasible, in which the water molecule is key to stabilize the phenolate ion-like nucleophile in the TS. This is the first computational insight into the inverting mechanism of an antibiotic natural product GT, and its implications may serve to guide the design of new biocatalysts for natural product glycodiversification.
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Affiliation(s)
- Fernanda Mendoza
- Departamento de Ciencias Químicas, Facultad de Ciencias Exactas, Universidad Andres Bello, Autopista Concepción-Talcahuano 7100, Talcahuano, Chile.
| | - Gonzalo A Jaña
- Departamento de Ciencias Químicas, Facultad de Ciencias Exactas, Universidad Andres Bello, Autopista Concepción-Talcahuano 7100, Talcahuano, Chile.
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