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Gloster TM, Meloncelli P, Stick RV, Zechel D, Vasella A, Davies GJ. Glycosidase Inhibition: An Assessment of the Binding of 18 Putative Transition-State Mimics. J Am Chem Soc 2007; 129:2345-54. [PMID: 17279749 DOI: 10.1021/ja066961g] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The inhibition of glycoside hydrolases, through transition-state mimicry, is important both as a probe of enzyme mechanism and in the continuing quest for new drugs, notably in the treatment of cancer, HIV, influenza, and diabetes. The high affinity with which these enzymes are known to bind the transition state provides a framework upon which to design potent inhibitors. Recent work [for example, Bülow, A. et al. J. Am. Chem. Soc. 2000, 122, 8567-8568; Zechel, D. L. et al. J. Am. Chem. Soc. 2003, 125, 14313-14323] has revealed quite confusing and counter-intuitive patterns of inhibition for a number of glycosidase inhibitors. Here we describe a synergistic approach for analysis of inhibitors with a single enzyme 'model system', the Thermotoga maritima family 1 beta-glucosidase, TmGH1. The pH dependence of enzyme activity and inhibition has been determined, structures of inhibitor complexes have been solved by X-ray crystallography, with data up to 1.65 A resolution, and isothermal titration calorimetry was used to establish the thermodynamic signature. This has allowed the characterization of 18 compounds, all putative transition-state mimics, in order to build an 'inhibition profile' that provides an insight into what governs binding. In contrast to our preconceptions, there is little correlation of inhibitor chemistry with the calorimetric dissection of thermodynamics. The ensemble of inhibitors shows strong enthalpy-entropy compensation, and the random distribution of similar inhibitors across the plot of DeltaH degrees a vs TDeltaS degrees a likely reflects the enormous contribution of solvation and desolvation effects on ligand binding.
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Jeyakanthan M, Meloncelli PJ, Zou L, Lowary TL, Larsen I, Maier S, Tao K, Rusch J, Chinnock R, Shaw N, Burch M, Beddows K, Addonizio L, Zuckerman W, Pahl E, Rutledge J, Kanter KR, Cairo CW, Buriak JM, Ross D, Rebeyka I, West LJ. ABH-Glycan Microarray Characterizes ABO Subtype Antibodies: Fine Specificity of Immune Tolerance After ABO-Incompatible Transplantation. Am J Transplant 2016; 16:1548-58. [PMID: 26602221 DOI: 10.1111/ajt.13625] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Revised: 10/18/2015] [Accepted: 11/07/2015] [Indexed: 01/25/2023]
Abstract
Organ transplantation from ABO blood group-incompatible (ABOi) donors requires accurate detection, effective removal and subsequent surveillance of antidonor antibodies. Because ABH antigen subtypes are expressed differently in various cells and organs, measurement of antibodies specific for the antigen subtypes in the graft is essential. Erythrocyte agglutination, the century-old assay used clinically, does not discriminate subtype-specific ABO antibodies and provides limited information on antibody isotypes. We designed and created an ABO-glycan microarray and demonstrated the precise assessment of both the presence and, importantly, the absence of donor-specific antibodies in an international study of pediatric heart transplant patients. Specific IgM, IgG, and IgA isotype antibodies to nonself ABH subtypes were detected in control participants and recipients of ABO-compatible transplants. Conversely, in children who received ABOi transplants, antibodies specific for A subtype II and/or B subtype II antigens-the only ABH antigen subtypes expressed in heart tissue-were absent, demonstrating the fine specificity of B cell tolerance to donor/graft blood group antigens. In contrast to the hemagglutination assay, the ABO-glycan microarray allows detailed characterization of donor-specific antibodies necessary for effective transplant management, representing a major step forward in precise ABO antibody detection.
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Jeyakanthan M, Tao K, Zou L, Meloncelli PJ, Lowary TL, Suzuki K, Boland D, Larsen I, Burch M, Shaw N, Beddows K, Addonizio L, Zuckerman W, Afzali B, Kim DH, Mengel M, Shapiro AMJ, West LJ. Chemical Basis for Qualitative and Quantitative Differences Between ABO Blood Groups and Subgroups: Implications for Organ Transplantation. Am J Transplant 2015; 15:2602-15. [PMID: 26014598 DOI: 10.1111/ajt.13328] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Revised: 03/01/2015] [Accepted: 03/20/2015] [Indexed: 01/25/2023]
Abstract
Blood group ABH(O) carbohydrate antigens are carried by precursor structures denoted type I-IV chains, creating unique antigen epitopes that may differ in expression between circulating erythrocytes and vascular endothelial cells. Characterization of such differences is invaluable in many clinical settings including transplantation. Monoclonal antibodies were generated and epitope specificities were characterized against chemically synthesized type I-IV ABH and related glycans. Antigen expression was detected on endomyocardial biopsies (n = 50) and spleen (n = 11) by immunohistochemical staining and on erythrocytes by flow cytometry. On vascular endothelial cells of heart and spleen, only type II-based ABH antigens were expressed; type III/IV structures were not detected. Type II-based ABH were expressed on erythrocytes of all blood groups. Group A1 and A2 erythrocytes additionally expressed type III/IV precursors, whereas group B and O erythrocytes did not. Intensity of A/B antigen expression differed among group A1 , A2 , A1 B, A2 B and B erythrocytes. On group A2 erythrocytes, type III H structures were largely un-glycosylated with the terminal "A" sugar α-GalNAc. Together, these studies define qualitative and quantitative differences in ABH antigen expression between erythrocytes and vascular tissues. These expression profiles have important implications that must be considered in clinical settings of ABO-incompatible transplantation when interpreting anti-ABO antibodies measured by hemagglutination assays with reagent erythrocytes.
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Slaney AM, Wright VA, Meloncelli PJ, Harris KD, West LJ, Lowary TL, Buriak JM. Biocompatible carbohydrate-functionalized stainless steel surfaces: a new method for passivating biomedical implants. ACS APPLIED MATERIALS & INTERFACES 2011; 3:1601-1612. [PMID: 21438637 DOI: 10.1021/am200158y] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A convenient method for passivating and functionalizing stainless steel is described. Several methods of coating stainless steel (SS) samples with silica were investigated and of these methods, a thin (less than 15 nm thick) layer of silica created by atomic layer deposition (ALD) was found to give superior performance in electrochemical testing. These interfaces were then used as a platform for further functionalization with molecules of biological interest. Specifically, the SS samples were functionalized with biologically significant carbohydrates [N-acetyl-D-glucosamine (GlcNAc) and D-galactose (Gal)] that contain trialkoxysilane derivatives as chemical handles for linking to the surface. The presence and biological availability of these moieties on the silica coated SS were confirmed by XPS analysis and an enzyme-linked lectin assay (ELLA) using complementary lectins that specifically recognize the surface-bound carbohydrate. This method has the potential of being adapted to the functionalization of stainless steel biomedical implants with other biologically relevant carbohydrates.
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Meloncelli PJ, West LJ, Lowary TL. Synthesis and NMR studies on the ABO histo-blood group antigens: synthesis of type III and IV structures and NMR characterization of type I-VI antigens. Carbohydr Res 2011; 346:1406-26. [PMID: 21531397 DOI: 10.1016/j.carres.2011.03.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2011] [Revised: 02/28/2011] [Accepted: 03/03/2011] [Indexed: 10/18/2022]
Abstract
The ABO histo-blood group antigens are best known for their important roles in solid organ and bone marrow transplantation as well as transfusion medicine. Here we report the synthesis of the ABO type III and IV antigens with a 7-octen-1-yl aglycone. Also described is an NMR study of the ABO type I to VI antigens, which were carried out to probe differences in overall conformation of the molecules. These NMR investigations showed very little difference in the (1)H chemical shifts, as well as (1)H-(1)H coupling constants, across all compounds, suggesting that these ABO subtypes adopt nearly identical conformations in solution.
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Higgins MA, Ficko-Blean E, Meloncelli PJ, Lowary TL, Boraston AB. The overall architecture and receptor binding of pneumococcal carbohydrate-antigen-hydrolyzing enzymes. J Mol Biol 2011; 411:1017-36. [PMID: 21767550 DOI: 10.1016/j.jmb.2011.06.035] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2011] [Revised: 06/16/2011] [Accepted: 06/20/2011] [Indexed: 11/19/2022]
Abstract
The TIGR4 and SP3-BS71 strains of Streptococcus pneumoniae each produce family 98 glycoside hydrolases, called Sp4GH98 and Sp3GH98, respectively, which have different modular architectures and substrate specificities. Sp4GH98 degrades the Lewis(Y) antigen and possesses three C-terminal family 47 carbohydrate-binding modules (CBMs) that bind to this substrate. Sp3GH98 degrades the blood group A/B antigens and has two N-terminal family 51 CBMs that are of unknown function. Here, we examine the complex carbohydrate-binding specificity of the family 51 CBMs from Sp3GH98 (referred to as CBM51-1 and CBM51-2), the structural basis of this interaction, and the overall solution conformations of both Sp3GH98 and Sp4GH98, which are shown to be fully secreted proteins. Through glycan microarray binding analysis and isothermal titration calorimetry, CBM51-1 is found to bind specifically to the blood group A/B antigens. However, due to a series of relatively small structural rearrangements that were revealed in structures determined by X-ray crystallography, CBM51-2 appears to be incapable of binding carbohydrates. Analysis of small-angle X-ray scattering data in combination with the available high-resolution X-ray crystal structures of the Sp3GH98 and Sp4GH98 catalytic modules and their CBMs yielded models of the biological solution structures of the full-length enzymes. These studies reveal the complex architectures of the two enzymes and suggest that carbohydrate recognition by the CBMs and the activity of the catalytic modules are not directly coupled.
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Abstract
The ABO histo-blood group antigens have long been of interest to chemists, biochemists, and evolutionary biologists. However, to date, a complete synthesis of all ABO histo-blood group antigens has not been conducted, despite the potential for such a panel to provide a more detailed understanding of the biological roles of these glycan motifs. Here we report the chemical synthesis of the A, B, and H type V and VI antigens in multi-milligramme quantities as part of an overall goal to prepare all 18 A, B, and H antigens. The A and B type V and VI antigens were prepared with a 7-octen-1-yl linker, to enable future conjugation to a protein or solid support. The H type V and VI antigens were prepared as the octyl glycoside, to facilitate detailed enzyme kinetics studies.
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Fiege B, Leuthold M, Parra F, Dalton KP, Meloncelli PJ, Lowary TL, Peters T. Epitope mapping of histo blood group antigens bound to norovirus VLPs using STD NMR experiments reveals fine details of molecular recognition. Glycoconj J 2017; 34:679-689. [PMID: 28823097 DOI: 10.1007/s10719-017-9792-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Revised: 08/04/2017] [Accepted: 08/08/2017] [Indexed: 01/06/2023]
Abstract
Attachment of human noroviruses to histo blood group antigens (HBGAs) is thought to be critical for the infection process. Therefore, we have determined binding epitopes of synthetic type 1 to 6 blood group A- and B-tetrasaccharides binding to GII.4 human Norovirus virus like particles (VLPs) using STD NMR experiments. So far, little information is available from crystal structure analysis studies on the interactions of the reducing-end sugars with the protruding domain (P-domain) of the viral coat protein VP1. Here, we show that the reducing-end sugars make notable contacts with the protein surface. The type of glycosidic linkage, and the identity of the sugar at the reducing end modulate HBGA recognition. Most strikingly, type 2 structures yield only very poor saturation transfer indicating impeded binding. This observation is in accordance with previous mass spectrometry based affinity measurements, and can be understood based on recent crystal structure data of a complex of highly homologous GII.4 P-dimers with H-type 2 trisaccharide where the N-acetyl group of the reducing N-acetyl glucosamine residue points towards a loop comprising amino acids Q390 to H395. We suggest that in our case, binding of type 2 A- and B-tetrasaccharides leads to steric conflicts with this loop. In order to identify factors determining L-Fuc recognition, we also synthesized GII.4 VLPs with point mutations D391A and H395A. Prior studies had suggested that these residues, located in a second shell around the L-Fuc binding site, assist L-Fuc binding. STD NMR experiments with L-Fuc and B-trisaccharide in the presence of wild type and mutant VLPs yield virtually identical binding epitopes suggesting that these two mutations do not significantly alter HBGA recognition. Our study emphasizes that recognition of α-(1→2)-linked L-Fuc residues is a conserved feature of GII.4 noroviruses. However, structural variation of the HBGA core structures clearly modulates molecular recognition depending on the genotype.
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Daskhan GC, Tran HTT, Meloncelli PJ, Lowary TL, West LJ, Cairo CW. Construction of Multivalent Homo- and Heterofunctional ABO Blood Group Glycoconjugates Using a Trifunctional Linker Strategy. Bioconjug Chem 2018; 29:343-362. [PMID: 29237123 DOI: 10.1021/acs.bioconjchem.7b00679] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The design and synthesis of multivalent ligands displaying complex oligosaccharides is necessary for the development of therapeutics, diagnostics, and research tools. Here, we report an efficient conjugation strategy to prepare complex glycoconjugates with 4 copies of 1 or 2 separate glycan epitopes, providing 4-8 carbohydrate residues on a tetravalent poly(ethylene glycol) scaffold. This strategy provides complex glycoconjugates that approach the size of glycoproteins (15-18 kDa) while remaining well-defined. The synthetic strategy makes use of three orthogonal functional groups, including a reactive N-hydroxysuccinimide (NHS)-ester moiety on the linker to install the first carbohydrate epitope via reaction with an amine. A masked amine functionality on the linker is revealed after the removal of a fluorenylmethyloxycarbonyl (Fmoc)-protecting group, allowing the attachment to the NHS-activated poly(ethylene glycol) (PEG) scaffold. An azide group in the linker was then used to incorporate the second carbohydrate epitope via catalyzed alkyne-azide cycloaddition. Using a known tetravalent PEG scaffold (PDI, 1.025), we prepared homofunctional glycoconjugates that display four copies of lactose and the A-type II or the B-type II human blood group antigens. Using our trifunctional linker, we expanded this strategy to produce heterofunctional conjugates with four copies of two separate glycan epitopes. These heterofunctional conjugates included Neu5Ac, 3'-sialyllactose, or 6'-sialyllactose as a second antigen. Using an alternative strategy, we generated heterofunctional conjugates with three copies of the glycan epitope and one fluorescent group (on average) using a sequential dual-amine coupling strategy. These conjugation strategies should be easily generalized for conjugation of other complex glycans. We demonstrate that the glycan epitopes of heterofunctional conjugates engage and cluster target B-cell receptors and CD22 receptors on B cells, supporting the application of these reagents for investigating cellular response to carbohydrate antigens of the ABO blood group system.
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Research Support, Non-U.S. Gov't |
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Meloncelli PJ, Williams TM, Hartmann PE, Stick RV. The synthesis of 2-, 3-, 4- and 6-O-α-d-glucopyranosyl-d-galactopyranose, and their evaluation as nutritional supplements for pre-term infants. Carbohydr Res 2007; 342:1793-804. [PMID: 17517382 DOI: 10.1016/j.carres.2007.04.022] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2007] [Revised: 04/20/2007] [Accepted: 04/25/2007] [Indexed: 11/25/2022]
Abstract
Four methods have been screened for the synthesis of some alpha-D-glucopyranosides, with the recently reported (Mukaiyama) combination of 2,3,4,6-tetra-O-benzyl-alpha-D-glucopyranosyl iodide and triphenylphosphine oxide being the most successful, especially in the diastereoselectivity exhibited. The alpha-D-glucopyranosides so obtained have been deprotected to yield 2-, 3-, 4- and 6-O-alpha-D-glucopyranosyl-D-galactopyranose. Only the last disaccharide showed any hydrolysis by alpha-glycosidases but this success was not emulated by mucosal extracts from the small intestine of the pig.
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Gagnon SML, Meloncelli PJ, Zheng RB, Haji-Ghassemi O, Johal AR, Borisova SN, Lowary TL, Evans SV. High Resolution Structures of the Human ABO(H) Blood Group Enzymes in Complex with Donor Analogs Reveal That the Enzymes Utilize Multiple Donor Conformations to Bind Substrates in a Stepwise Manner. J Biol Chem 2015; 290:27040-27052. [PMID: 26374898 DOI: 10.1074/jbc.m115.682401] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Indexed: 11/06/2022] Open
Abstract
Homologous glycosyltransferases α-(1→3)-N-acetylgalactosaminyltransferase (GTA) and α-(1→3)-galactosyltransferase (GTB) catalyze the final step in ABO(H) blood group A and B antigen synthesis through sugar transfer from activated donor to the H antigen acceptor. These enzymes have a GT-A fold type with characteristic mobile polypeptide loops that cover the active site upon substrate binding and, despite intense investigation, many aspects of substrate specificity and catalysis remain unclear. The structures of GTA, GTB, and their chimeras have been determined to between 1.55 and 1.39 Å resolution in complex with natural donors UDP-Gal, UDP-Glc and, in an attempt to overcome one of the common problems associated with three-dimensional studies, the non-hydrolyzable donor analog UDP-phosphono-galactose (UDP-C-Gal). Whereas the uracil moieties of the donors are observed to maintain a constant location, the sugar moieties lie in four distinct conformations, varying from extended to the "tucked under" conformation associated with catalysis, each stabilized by different hydrogen bonding partners with the enzyme. Further, several structures show clear evidence that the donor sugar is disordered over two of the observed conformations and so provide evidence for stepwise insertion into the active site. Although the natural donors can both assume the tucked under conformation in complex with enzyme, UDP-C-Gal cannot. Whereas UDP-C-Gal was designed to be "isosteric" with natural donor, the small differences in structure imposed by changing the epimeric oxygen atom to carbon appear to render the enzyme incapable of binding the analog in the active conformation and so preclude its use as a substrate mimic in GTA and GTB.
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Meloncelli PJ, Stick RV. Improvements to the Synthesis of Isofagomine, Noeuromycin, Azafagomine, and Isofagomine Lactam, and a Synthesis of Azanoeuromycin and 'Guanidine' Isofagomine. Aust J Chem 2006. [DOI: 10.1071/ch06241] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Improvements in the preparation of a key imidazylate and the reduction of the derived nitrile have led to more efficient syntheses of isofagomine, noeuromycin, azafagomine, and isofagomine lactam. As well, a precursor of azafagomine has been converted into azanoeuromycin, and the nitrogen atom of isofagomine has been incorporated into a guanidine residue.
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Slaney AM, Dijke IE, Jeyakanthan M, Li C, Zou L, Plaza-Alexander P, Meloncelli PJ, Bau JA, Allan LL, Lowary TL, West LJ, Cairo CW, Buriak JM. Conjugation of A and B Blood Group Structures to Silica Microparticles for the Detection of Antigen-Specific B Cells. Bioconjug Chem 2016; 27:705-15. [PMID: 26816334 DOI: 10.1021/acs.bioconjchem.5b00672] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Silica microparticles were functionalized with A and B blood group carbohydrate antigens (A type I, A type II, B type I, and B type II) to enable the detection and monitoring of ABO antigen-specific B cells. Microparticles were prepared via the Stöber synthesis, labeled with an Alexafluor fluorescent dye, and characterized via TEM and fluorescence microscopy. The silica microparticles were functionalized with (3-aminopropyl)trimethoxysilane (APTMS), followed by the use of an established fluorenylmethyloxycarbonyl (Fmoc)-protected PEG-based linker. The terminal Fmoc moiety of the PEG-based linker was then deprotected, yielding free amino groups, to which the A and B antigens were coupled. The carbohydrate antigens were synthesized with a p-nitrophenol ester to enable conjugation to the functionalized silica microparticles via an amide bond. The number of free amine groups available for coupling for a given mass of PEG-functionalized silica microparticles was quantified via reaction with Fmoc-glycine. The antigen-functionalized microparticles were then evaluated for their specificity in binding to A and B antigen-reactive B-cells via flow cytometry, and for blocking of naturally occurring antibodies in human serum. Selective binding of the functionalized microparticles to blood group-reactive B cells was observed by flow cytometry and fluorescence microscopy. The modular approach outlined here is applicable to the preparation of silica microparticles containing any carbohydrate antigen and alternative fluorophores or labels. This approach therefore comprises a novel, general platform for screening B cell populations for binding to carbohydrate antigens, including, in this case, the human A and B blood group antigens.
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Meloncelli PJ, Gloster TM, Money VA, Tarling CA, Davies GJ, Withers SG, Stick RV. D-Glucosylated Derivatives of Isofagomine and Noeuromycin and Their Potential as Inhibitors of β-Glycoside Hydrolases. Aust J Chem 2007. [DOI: 10.1071/ch07188] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
While isofagomine and noeuromycin have previously been demonstrated to be effective inhibitors of a range of exo-acting glycosidases, they are usually only very weak inhibitors of endo-glycosidases. However, the disaccharide-like 3- and 4-O-β-d-glucopyranosylisofagomines have proven to be strong inhibitors of these endo-acting enzymes that utilize multiple sub-sites. In an attempt to emulate these successes, we have prepared 3- and 4-O-β-d-glucopyranosylnoeuromycin, the former by a selective glycosylation (at O2) of benzyl 4-C-cyano-4-deoxy-α-d-arabinoside (also leading to another synthesis of 3-O-β-d-glucopyranosylisofagomine), the latter by a non-selective glycosylation of benzyl 4-O-allyl-β-l-xyloside with subsequent introduction of the required nitrile group (also leading to another synthesis of 4-O-β-d-glucopyranosylisofagomine). 3-O-β-d-Glucopyranosylnoeuromycin was evaluated as an inhibitor of a family 26 lichenase from Clostridium thermocellum, and 4-O-β-d-glucopyranosylnoeuromycin as an inhibitor of both a family 5 endo-glucanase from Bacillus agaradhaerans and a family 10 endo-xylanase from Cellulomonas fimi. We also report X-ray structural investigations of 3- and 4-O-β-d-glucopyranosylnoeuromycin in complex with the family 26 and family 5 β-glycoside hydrolases, respectively. The two d-glucosylated noeuromycins were indeed able to harness the additional binding energy from the sub-sites of their endo-glycoside hydrolase targets, and were thus excellent inhibitors (in the nanomolar range), binding as expected in the –1 and –2 sub-sites of the enzymes.
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Gagnon SM, Meloncelli PJ, Zheng RB, Haji-Ghassemi O, Johal AR, Borisova SN, Lowary TL, Evans SV. High resolution structures of the human ABO(H) blood group enzymes in complex with donor analogs reveal that the enzymes utilize multiple donor conformations to bind substrates in a stepwise manner. J Biol Chem 2016; 291:7229. [DOI: 10.1074/jbc.a115.682401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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