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Lethe MCL, Paris V, Wang X, Chan CTY. Similarities in Structure and Function of UDP-Glycosyltransferase Homologs from Human and Plants. Int J Mol Sci 2024; 25:2782. [PMID: 38474028 PMCID: PMC10932239 DOI: 10.3390/ijms25052782] [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: 01/25/2024] [Revised: 02/23/2024] [Accepted: 02/25/2024] [Indexed: 03/14/2024] Open
Abstract
The uridine diphosphate glycosyltransferase (UGT) superfamily plays a key role in the metabolism of xenobiotics and metabolic wastes, which is essential for detoxifying those species. Over the last several decades, a huge effort has been put into studying human and mammalian UGT homologs, but family members in other organisms have been explored much less. Potentially, other UGT homologs can have desirable substrate specificity and biological activities that can be harnessed for detoxification in various medical settings. In this review article, we take a plant UGT homology, UGT71G1, and compare its structural and biochemical properties with the human homologs. These comparisons suggest that even though mammalian and plant UGTs are functional in different environments, they may support similar biochemical activities based on their protein structure and function. The known biological functions of these homologs are discussed so as to provide insights into the use of UGT homologs from other organisms for addressing human diseases related to UGTs.
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Affiliation(s)
- Mary Caroline L. Lethe
- Department of Biomedical Engineering, College of Engineering, University of North Texas, 3940 N Elm Street, Denton, TX 76207, USA (V.P.)
| | - Vincent Paris
- Department of Biomedical Engineering, College of Engineering, University of North Texas, 3940 N Elm Street, Denton, TX 76207, USA (V.P.)
| | - Xiaoqiang Wang
- Department of Biological Sciences, College of Science, University of North Texas, 1155 Union Circle #305220, Denton, TX 76203, USA;
- BioDiscovery Institute, University of North Texas, 1155 Union Circle #305220, Denton, TX 76203, USA
| | - Clement T. Y. Chan
- Department of Biomedical Engineering, College of Engineering, University of North Texas, 3940 N Elm Street, Denton, TX 76207, USA (V.P.)
- BioDiscovery Institute, University of North Texas, 1155 Union Circle #305220, Denton, TX 76203, USA
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Arriaza RH, Abiskaroon B, Patel M, Daneshian L, Kluza A, Snoeck S, Watkins MB, Hopkins JB, Van Leeuwen T, Grbic M, Grbic V, Borowski T, Chruszcz M. Structural and functional studies reveal the molecular basis of substrate promiscuity of a glycosyltransferase originating from a major agricultural pest. J Biol Chem 2023; 299:105421. [PMID: 37923139 PMCID: PMC10731231 DOI: 10.1016/j.jbc.2023.105421] [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: 09/18/2023] [Revised: 10/16/2023] [Accepted: 10/26/2023] [Indexed: 11/07/2023] Open
Abstract
The two-spotted spider mite, Tetranychus urticae, is a major cosmopolitan pest that feeds on more than 1100 plant species. Its genome contains an unprecedentedly large number of genes involved in detoxifying and transporting xenobiotics, including 80 genes that code for UDP glycosyltransferases (UGTs). These enzymes were acquired via horizontal gene transfer from bacteria after loss in the Chelicerata lineage. UGTs are well-known for their role in phase II metabolism; however, their contribution to host adaptation and acaricide resistance in arthropods, such as T. urticae, is not yet resolved. TuUGT202A2 (Tetur22g00270) has been linked to the ability of this pest to adapt to tomato plants. Moreover, it was shown that this enzyme can glycosylate a wide range of flavonoids. To understand this relationship at the molecular level, structural, functional, and computational studies were performed. Structural studies provided specific snapshots of the enzyme in different catalytically relevant stages. The crystal structure of TuUGT202A2 in complex with UDP-glucose was obtained and site-directed mutagenesis paired with molecular dynamic simulations revealed a novel lid-like mechanism involved in the binding of the activated sugar donor. Two additional TuUGT202A2 crystal complexes, UDP-(S)-naringenin and UDP-naringin, demonstrated that this enzyme has a highly plastic and open-ended acceptor-binding site. Overall, this work reveals the molecular basis of substrate promiscuity of TuUGT202A2 and provides novel insights into the structural mechanism of UGTs catalysis.
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Affiliation(s)
- Ricardo Hernandez Arriaza
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA; Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina, USA
| | - Brendan Abiskaroon
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA
| | - Megha Patel
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina, USA
| | - Leily Daneshian
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina, USA
| | - Anna Kluza
- Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Science, Krakow, Poland
| | - Simon Snoeck
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Maxwell B Watkins
- The Biophysics Collaborative Access Team (BioCAT), Department of Physics, Illinois Institute of Technology, Chicago, Illinois, USA
| | - Jesse B Hopkins
- The Biophysics Collaborative Access Team (BioCAT), Department of Physics, Illinois Institute of Technology, Chicago, Illinois, USA
| | - Thomas Van Leeuwen
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Miodrag Grbic
- Department of Biology, Western University, London, Ontario, Canada; University of La Rioja, Logrono, Spain
| | - Vojislava Grbic
- Department of Biology, Western University, London, Ontario, Canada
| | - Tomasz Borowski
- Jerzy Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Science, Krakow, Poland
| | - Maksymilian Chruszcz
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA; Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina, USA.
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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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Ünal E, Sulukan E, Şenol O, Baran A, Nadaroğlu H, Kankaynar M, Kızıltan T, Ceyhun SB. Antioxidant/protective effects of carob pod (Ceratonia siliqua L.) water extract against deltamethrin-induced oxidative stress/toxicity in zebrafish larvae. Comp Biochem Physiol C Toxicol Pharmacol 2023; 267:109584. [PMID: 36822298 DOI: 10.1016/j.cbpc.2023.109584] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 02/14/2023] [Accepted: 02/16/2023] [Indexed: 02/23/2023]
Abstract
In our study, the antioxidant capacity of carob pods water extract (CPWE) against deltamethrin (DM)-induced oxidative stress, a widely used pesticide around the world, was investigated in vitro and in vivo in a zebrafish model. The in vitro antioxidant capacity of the obtained extract was evaluated with different methods using trolox, BHA and BHT standard antioxidants. For in vivo experiments, 4hpf zebrafish embryos were exposed to 10 ppb and 25 ppb DM for 120 h and the larvae were treated with 1-10 and 100 ppm CPWE for 4 h at 72th hours. According to the results obtained, it has been determined that the exposure of zebrafish to DM during the developmental period causes important body malformations, decrease in survival rate, reduction in eye size, shortening in body length and decrease in locomotor activity in the dark period. In addition, according to the results of whole-mount staining, it was determined that DM caused a significant increase in the amount of free oxygen radicals and apoptotic cells. It was also confirmed by metabolome analysis that CPWE application for 4 h reduced DM-induced toxicity and oxidative stress. As a result, it can be said that CPWE has an important antioxidant capacity in eliminating DM-induced oxidative stress.
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Affiliation(s)
- Elif Ünal
- Department of Nanoscience and Nanoengineering, Graduate School of Natural and Applied Science, Atatürk University, Erzurum, Turkey; Aquatic Biotechnology Laboratory, Fisheries Faculty, Atatürk University, Erzurum, Turkey
| | - Ekrem Sulukan
- Aquatic Biotechnology Laboratory, Fisheries Faculty, Atatürk University, Erzurum, Turkey; Department of Aquaculture Engineering, Graduate School of Natural and Applied Science, Atatürk University, Erzurum, Turkey; Aquaculture Department, Fisheries Faculty, Atatürk University, Erzurum, Turkey
| | - Onur Şenol
- Department of Analytical Chemistry, Faculty of Pharmacy, Atatürk University, Erzurum, Turkey
| | - Alper Baran
- Department of Nanoscience and Nanoengineering, Graduate School of Natural and Applied Science, Atatürk University, Erzurum, Turkey; Aquatic Biotechnology Laboratory, Fisheries Faculty, Atatürk University, Erzurum, Turkey; Department of Food Quality Control and Analysis, Technical Vocational School, Atatürk University, Erzurum, Turkey
| | - Hayrunnisa Nadaroğlu
- Department of Nanoscience and Nanoengineering, Graduate School of Natural and Applied Science, Atatürk University, Erzurum, Turkey; Department of Food Quality Control and Analysis, Technical Vocational School, Atatürk University, Erzurum, Turkey
| | - Meryem Kankaynar
- Department of Nanoscience and Nanoengineering, Graduate School of Natural and Applied Science, Atatürk University, Erzurum, Turkey; Aquatic Biotechnology Laboratory, Fisheries Faculty, Atatürk University, Erzurum, Turkey
| | - Tuba Kızıltan
- Department of Nanoscience and Nanoengineering, Graduate School of Natural and Applied Science, Atatürk University, Erzurum, Turkey; Aquatic Biotechnology Laboratory, Fisheries Faculty, Atatürk University, Erzurum, Turkey
| | - Saltuk Buğrahan Ceyhun
- Department of Nanoscience and Nanoengineering, Graduate School of Natural and Applied Science, Atatürk University, Erzurum, Turkey; Aquatic Biotechnology Laboratory, Fisheries Faculty, Atatürk University, Erzurum, Turkey; Department of Aquaculture Engineering, Graduate School of Natural and Applied Science, Atatürk University, Erzurum, Turkey; Aquaculture Department, Fisheries Faculty, Atatürk University, Erzurum, Turkey.
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5
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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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Dias VHV, Mattos JJ, Bastolla CLV, Lüchmann KH, Bainy ACD. Characterisation of UDP-glucuronosyltransferase activity in sea turtle Chelonia mydas. Xenobiotica 2022; 52:1011-1019. [PMID: 36594659 DOI: 10.1080/00498254.2022.2164750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Uridine diphosphate glucuronosyltransferase (UGT) enzymes conjugate many lipophilic chemicals, such as drugs, environmental contaminants, and endogenous compounds, promoting their excretion. The complexity of UGT kinetics, and the location of enzyme active site in endoplasmic reticulum lumen, requires an accurate optimisation of enzyme assays.In the present study, we characterised UGT activity in liver microsomes of green turtles (Chelonia mydas), an endangered species. The conditions for measuring UGT activity were standardised through spectrofluorimetric methods, using the substrates 4-methylumbelliferone (4-MU) and uridine diphosphate glucuronic acid (UDPGA) at 30 °C and pH 7.4.The green turtles showed UGT activity at the saturating concentrations of substrates of 250 µM to 4-MU and 7 mM to UDPGA. The alamethicin, Brij®58, bovine serum albumin (BSA), and magnesium increased UGT activity. The assay using alamethicin (22 µg per mg of protein), magnesium (1 mM), and BSA (0.25%) reached the highest Vmax (1203 pmol·min-1mg·protein-1). Lithocholic acid and diclofenac inhibited UGT activity in green turtles.This study is the first report of UGT activity in the liver of green turtles and provides a base for future studies to understand the mechanisms of toxicity by exposure to contaminants in this charismatic species.
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Affiliation(s)
- Vera Helena V Dias
- Laboratory of Biomarkers of Aquatic Contamination and Immunochemistry-LABCAI, Federal University of Santa Catarina, Florianópolis, Brazil
| | - Jacó J Mattos
- Aquaculture Pathology Research Center-NEPAQ, Federal University of Santa Catarina, Florianópolis, Brazil
| | - Camila L V Bastolla
- Laboratory of Biomarkers of Aquatic Contamination and Immunochemistry-LABCAI, Federal University of Santa Catarina, Florianópolis, Brazil
| | - Karim H Lüchmann
- Department of Scientific and Technological Education, Santa Catarina State University, Florianópolis, Brazil
| | - Afonso C D Bainy
- Laboratory of Biomarkers of Aquatic Contamination and Immunochemistry-LABCAI, Federal University of Santa Catarina, Florianópolis, Brazil
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7
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Computational prediction for the metabolism of human UDP-glucuronosyltransferase 1A1 substrates. Comput Biol Med 2022; 149:105959. [DOI: 10.1016/j.compbiomed.2022.105959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 07/31/2022] [Accepted: 08/06/2022] [Indexed: 11/15/2022]
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Robin S, Hassine KB, Muthukumaran J, Jurkovic Mlakar S, Krajinovic M, Nava T, Uppugunduri CRS, Ansari M. A potential implication of UDP-glucuronosyltransferase 2B10 in the detoxification of drugs used in pediatric hematopoietic stem cell transplantation setting: an in silico investigation. BMC Mol Cell Biol 2022; 23:5. [PMID: 35062878 PMCID: PMC8781437 DOI: 10.1186/s12860-021-00402-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 12/22/2021] [Indexed: 12/19/2022] Open
Abstract
Background Sinusoidal occlusion syndrome (SOS) is a potentially severe complication following hematopoietic stem cell transplantation (HSCT) in pediatric patients. Treatment related risk factors such as intensity of conditioning, hepatotoxic co-medication and patient related factors such as genetic variants predispose individuals to develop SOS. The variant allele for SNP rs17146905 in UDP-glucuronosyl transferase 2B10 (UGT2B10) gene was correlated with the occurrence of SOS in an exome-wide association study. UGT2B10 is a phase II drug metabolizing enzyme involved in the N-glucuronidation of tertiary amine containing drugs. Methods To shed light on the functionality of UGT2B10 enzyme in the metabolism of drugs used in pediatric HSCT setting, we performed in silico screening against custom based library of putative ligands. First, a list of potential substrates for in silico analysis was prepared using a systematic consensus-based strategy. The list comprised of drugs and their metabolites used in pediatric HSCT setting. The three-dimensional structure of UGT2B10 was not available from the Research Collaboratory Structural Bioinformatics - Protein Data Bank (RCSB - PDB) repository and thus we predicted the first human UGT2B10 3D model by using multiple template homology modeling with MODELLER Version 9.2 and molecular docking calculations with AutoDock Vina Version 1.2 were implemented to quantify the estimated binding affinity between selected putative substrates or ligands and UGT2B10. Finally, we performed molecular dynamics simulations using GROMACS Version 5.1.4 to confirm the potential UGT2B10 ligands prioritized after molecular docking (exhibiting negative free binding energy). Results Four potential ligands for UGT2B10 namely acetaminophen, lorazepam, mycophenolic acid and voriconazole n-oxide intermediate were identified. Other metabolites of voriconazole satisfied the criteria of being possible ligands of UGT2B10. Except for bilirubin and 4-Hydroxy Voriconazole, all the ligands (particularly voriconazole and hydroxy voriconazole) are oriented in substrate binding site close to the co-factor UDP (mean ± SD; 0.72 ± 0.33 nm). Further in vitro screening of the putative ligands prioritized by in silico pipeline is warranted to understand the nature of the ligands either as inhibitors or substrates of UGT2B10. Conclusions These results may indicate the clinical and pharmacological relevance UGT2B10 in pediatric HSCT setting. With this systematic computational methodology, we provide a rational-, time-, and cost-effective way to identify and prioritize the interesting putative substrates or inhibitors of UGT2B10 for further testing in in vitro experiments. Supplementary Information The online version contains supplementary material available at 10.1186/s12860-021-00402-5.
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Ehrlich JJ, Weerts RM, Shome S, Culbertson AT, Honzatko RB, Jernigan RL, Zabotina OA. Xyloglucan Xylosyltransferase 1 Displays Promiscuity Toward Donor Substrates During in Vitro Reactions. PLANT & CELL PHYSIOLOGY 2021; 62:1890-1901. [PMID: 34265062 DOI: 10.1093/pcp/pcab114] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 07/11/2021] [Accepted: 07/14/2021] [Indexed: 05/26/2023]
Abstract
Glycosyltransferases (GTs) are a large family of enzymes that add sugars to a broad range of acceptor substrates, including polysaccharides, proteins and lipids, by utilizing a wide variety of donor substrates in the form of activated sugars. Individual GTs have generally been considered to exhibit a high level of substrate specificity, but this has not been thoroughly investigated across the extremely large set of GTs. Here we investigate xyloglucan xylosyltransferase 1 (XXT1), a GT involved in the synthesis of the plant cell wall polysaccharide, xyloglucan. Xyloglucan has a glucan backbone, with initial side chain substitutions exclusively composed of xylose from uridine diphosphate (UDP)-xylose. While this conserved substitution pattern suggests a high substrate specificity for XXT1, our in vitro kinetic studies elucidate a more complex set of behavior. Kinetic studies demonstrate comparable kcat values for reactions with UDP-xylose and UDP-glucose, while reactions with UDP-arabinose and UDP-galactose are over 10-fold slower. Using kcat/KM as a measure of efficiency, UDP-xylose is 8-fold more efficient as a substrate than the next best alternative, UDP-glucose. To the best of our knowledge, we are the first to demonstrate that not all plant XXTs are highly substrate specific and some do show significant promiscuity in their in vitro reactions. Kinetic parameters alone likely do not explain the high substrate selectivity in planta, suggesting that there are additional control mechanisms operating during polysaccharide biosynthesis. Improved understanding of substrate specificity of the GTs will aid in protein engineering, development of diagnostic tools, and understanding of biological systems.
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Affiliation(s)
- Jacqueline J Ehrlich
- Roy J Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, 1210 Molecular Biology Building, 2437 Pammel Drive, Ames IA 50011-1079, USA
- Department of Molecular Biology & Genetics, 107 Biotechnology Building, 526 Campus Road, Cornell University, Ithaca, NY 14853-2703, USA
| | - Richard M Weerts
- Roy J Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, 1210 Molecular Biology Building, 2437 Pammel Drive, Ames IA 50011-1079, USA
| | - Sayane Shome
- Roy J Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, 1210 Molecular Biology Building, 2437 Pammel Drive, Ames IA 50011-1079, USA
| | - Alan T Culbertson
- Roy J Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, 1210 Molecular Biology Building, 2437 Pammel Drive, Ames IA 50011-1079, USA
- Department of Cell Biology, Harvard Medical School, 240 Longwood Ave., Boston, MA 02115, USA
| | - Richard B Honzatko
- Roy J Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, 1210 Molecular Biology Building, 2437 Pammel Drive, Ames IA 50011-1079, USA
| | - Robert L Jernigan
- Roy J Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, 1210 Molecular Biology Building, 2437 Pammel Drive, Ames IA 50011-1079, USA
| | - Olga A Zabotina
- Roy J Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, 1210 Molecular Biology Building, 2437 Pammel Drive, Ames IA 50011-1079, USA
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10
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Nair PC, Chau N, McKinnon RA, Miners JO. Arginine-259 of UGT2B7 Confers UDP-Sugar Selectivity. Mol Pharmacol 2020; 98:710-718. [PMID: 33008919 DOI: 10.1124/molpharm.120.000104] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 09/17/2020] [Indexed: 11/22/2022] Open
Abstract
Enzymes of the human UDP-glycosyltransferase (UGT) superfamily typically catalyze the covalent addition of the sugar moiety from a UDP-sugar cofactor to relatively low-molecular weight lipophilic compounds. Although UDP-glucuronic acid (UDP-GlcUA) is most commonly employed as the cofactor by UGT1 and UGT2 family enzymes, UGT2B7 and several other enzymes can use both UDP-GlcUA and UDP-glucose (UDP-Glc), leading to the formation of glucuronide and glucoside conjugates. An investigation of UGT2B7-catalyzed morphine glycosidation indicated that glucuronidation is the principal route of metabolism because the binding affinity of UDP-GlcUA is higher than that of UDP-Glc. Currently, it is unclear which residues in the UGT2B7 cofactor binding domain are responsible for the preferential binding of UDP-GlcUA. Here, molecular dynamics (MD) simulations were performed together with site-directed mutagenesis and enzyme kinetic studies to identify residues within the UGT2B7 binding site responsible for the selective cofactor binding. MD simulations demonstrated that Arg259, which is located within the N-terminal domain, specifically interacts with UDP-GlcUA, whereby the side chain of Arg259 H-bonds and forms a salt bridge with the carboxylate group of glucuronic acid. Consistent with the MD simulations, substitution of Arg259 with Leu resulted in the loss of morphine, 4-methylumbelliferone, and zidovudine glucuronidation activity, but morphine glucosidation was preserved. SIGNIFICANCE STATEMENT: Despite the importance of uridine diphosphate glycosyltransferase (UGT) enzymes in drug and chemical metabolism, cofactor binding interactions are incompletely understood, as is the molecular basis for preferential glucuronidation by UGT1 and UGT2 family enzymes. The study demonstrated that long timescale molecular dynamics (MD) simulations with a UGT2B7 homology model can be used to identify critical binding interactions of a UGT protein with UDP-sugar cofactors. Further, the data provide a basis for the application of MD simulations to the elucidation of UGT-aglycone interactions.
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Affiliation(s)
- Pramod C Nair
- Department of Clinical Pharmacology (P.C.N., N.C., J.O.M.) and Flinders Health and Medical Research Institute (FHMRI) Cancer Program (P.C.N., R.A.M., J.O.M.), Flinders Health and Medical Research Institute, Flinders University College of Medicine and Public Health, Flinders Medical Centre, South Australia, Australia
| | - Nuy Chau
- Department of Clinical Pharmacology (P.C.N., N.C., J.O.M.) and Flinders Health and Medical Research Institute (FHMRI) Cancer Program (P.C.N., R.A.M., J.O.M.), Flinders Health and Medical Research Institute, Flinders University College of Medicine and Public Health, Flinders Medical Centre, South Australia, Australia
| | - Ross A McKinnon
- Department of Clinical Pharmacology (P.C.N., N.C., J.O.M.) and Flinders Health and Medical Research Institute (FHMRI) Cancer Program (P.C.N., R.A.M., J.O.M.), Flinders Health and Medical Research Institute, Flinders University College of Medicine and Public Health, Flinders Medical Centre, South Australia, Australia
| | - John O Miners
- Department of Clinical Pharmacology (P.C.N., N.C., J.O.M.) and Flinders Health and Medical Research Institute (FHMRI) Cancer Program (P.C.N., R.A.M., J.O.M.), Flinders Health and Medical Research Institute, Flinders University College of Medicine and Public Health, Flinders Medical Centre, South Australia, Australia
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