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Grozdanovic MM, Doyle CB, Liu L, Maybruck BT, Kwatia MA, Thiyagarajan N, Acharya KR, Ackerman SJ. Charcot-Leyden crystal protein/galectin-10 interacts with cationic ribonucleases and is required for eosinophil granulogenesis. J Allergy Clin Immunol 2020; 146:377-389.e10. [PMID: 31982451 DOI: 10.1016/j.jaci.2020.01.013] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 10/28/2019] [Accepted: 01/03/2020] [Indexed: 01/10/2023]
Abstract
BACKGROUND The human eosinophil Charcot-Leyden crystal (CLC) protein is a member of the Galectin superfamily and is also known as galectin-10 (Gal-10). CLC/Gal-10 forms the distinctive hexagonal bipyramidal crystals that are considered hallmarks of eosinophil participation in allergic responses and related inflammatory reactions; however, the glycan-containing ligands of CLC/Gal-10, its cellular function(s), and its role(s) in allergic diseases are unknown. OBJECTIVE We sought to determine the binding partners of CLC/Gal-10 and elucidate its role in eosinophil biology. METHODS Intracellular binding partners were determined by ligand blotting with CLC/Gal-10, followed by coimmunoprecipitation and coaffinity purifications. The role of CLC/Gal-10 in eosinophil function was determined by using enzyme activity assays, confocal microscopy, and short hairpin RNA knockout of CLC/Gal-10 expression in human CD34+ cord blood hematopoietic progenitors differentiated to eosinophils. RESULTS CLC/Gal-10 interacts with both human eosinophil granule cationic ribonucleases (RNases), namely, eosinophil-derived neurotoxin (RNS2) and eosinophil cationic protein (RNS3), and with murine eosinophil-associated RNases. The interaction is independent of glycosylation and is not inhibitory toward endoRNase activity. Activation of eosinophils with INF-γ induces the rapid colocalization of CLC/Gal-10 with eosinophil-derived neurotoxin/RNS2 and CD63. Short hairpin RNA knockdown of CLC/Gal-10 in human cord blood-derived CD34+ progenitor cells impairs eosinophil granulogenesis. CONCLUSIONS CLC/Gal-10 functions as a carrier for the sequestration and vesicular transport of the potent eosinophil granule cationic RNases during both differentiation and degranulation, enabling their intracellular packaging and extracellular functions in allergic inflammation.
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Affiliation(s)
- Milica M Grozdanovic
- Department of Biochemistry and Molecular Genetics, College of Medicine, University of Illinois at Chicago, Chicago, Ill
| | - Christine B Doyle
- Department of Biochemistry and Molecular Genetics, College of Medicine, University of Illinois at Chicago, Chicago, Ill
| | - Li Liu
- Department of Biochemistry and Molecular Genetics, College of Medicine, University of Illinois at Chicago, Chicago, Ill
| | - Brian T Maybruck
- Department of Biochemistry and Molecular Genetics, College of Medicine, University of Illinois at Chicago, Chicago, Ill
| | - Mark A Kwatia
- Department of Biochemistry and Molecular Genetics, College of Medicine, University of Illinois at Chicago, Chicago, Ill
| | - Nethaji Thiyagarajan
- Department of Biology and Biochemistry, University of Bath, Bath, United Kingdom
| | - K Ravi Acharya
- Department of Biology and Biochemistry, University of Bath, Bath, United Kingdom
| | - Steven J Ackerman
- Department of Biochemistry and Molecular Genetics, College of Medicine, University of Illinois at Chicago, Chicago, Ill.
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2
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Bunney TD, Inglis AJ, Sanfelice D, Farrell B, Kerr CJ, Thompson GS, Masson GR, Thiyagarajan N, Svergun DI, Williams RL, Breeze AL, Katan M. Disease Variants of FGFR3 Reveal Molecular Basis for the Recognition and Additional Roles for Cdc37 in Hsp90 Chaperone System. Structure 2018; 26:446-458.e8. [PMID: 29478821 PMCID: PMC5846801 DOI: 10.1016/j.str.2018.01.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Revised: 12/06/2017] [Accepted: 01/26/2018] [Indexed: 11/21/2022]
Abstract
Receptor tyrosine kinase FGFR3 is involved in many signaling networks and is frequently mutated in developmental disorders and cancer. The Hsp90/Cdc37 chaperone system is essential for function of normal and neoplastic cells. Here we uncover the mechanistic inter-relationships between these proteins by combining approaches including NMR, HDX-MS, and SAXS. We show that several disease-linked mutations convert FGFR3 to a stronger client, where the determinant underpinning client strength involves an allosteric network through the N-lobe and at the lobe interface. We determine the architecture of the client kinase/Cdc37 complex and demonstrate, together with site-specific information, that binding of Cdc37 to unrelated kinases induces a common, extensive conformational remodeling of the kinase N-lobe, beyond localized changes and interactions within the binary complex. As further shown for FGFR3, this processing by Cdc37 deactivates the kinase and presents it, in a specific orientation established in the complex, for direct recognition by Hsp90.
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Affiliation(s)
- Tom D Bunney
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St, London WC1E 6BT, UK.
| | - Alison J Inglis
- Medical Research Council (MRC) Laboratory of Molecular Biology, Cambridge CB2 0QH, UK
| | - Domenico Sanfelice
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St, London WC1E 6BT, UK
| | - Brendan Farrell
- Astbury Centre for Structural Molecular Biology, Faculty of Biological Sciences, Leeds LS2 9JT, UK
| | - Christopher J Kerr
- European Molecular Biology Laboratory (EMBL) Hamburg Outstation, DESY, Hamburg, Germany
| | - Gary S Thompson
- Astbury Centre for Structural Molecular Biology, Faculty of Biological Sciences, Leeds LS2 9JT, UK
| | - Glenn R Masson
- Medical Research Council (MRC) Laboratory of Molecular Biology, Cambridge CB2 0QH, UK
| | - Nethaji Thiyagarajan
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St, London WC1E 6BT, UK
| | - Dmitri I Svergun
- European Molecular Biology Laboratory (EMBL) Hamburg Outstation, DESY, Hamburg, Germany
| | - Roger L Williams
- Medical Research Council (MRC) Laboratory of Molecular Biology, Cambridge CB2 0QH, UK
| | - Alexander L Breeze
- Astbury Centre for Structural Molecular Biology, Faculty of Biological Sciences, Leeds LS2 9JT, UK.
| | - Matilda Katan
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St, London WC1E 6BT, UK.
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3
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Bradshaw WJ, Rehman S, Pham TTK, Thiyagarajan N, Lee RL, Subramanian V, Acharya KR. Structural insights into human angiogenin variants implicated in Parkinson's disease and Amyotrophic Lateral Sclerosis. Sci Rep 2017; 7:41996. [PMID: 28176817 PMCID: PMC5296752 DOI: 10.1038/srep41996] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Accepted: 01/04/2017] [Indexed: 12/11/2022] Open
Abstract
Mutations in Angiogenin (ANG), a member of the Ribonuclease A superfamily (also known as RNase 5) are known to be associated with Amyotrophic Lateral Sclerosis (ALS, motor neurone disease) (sporadic and familial) and Parkinson’s Disease (PD). In our previous studies we have shown that ANG is expressed in neurons during neuro-ectodermal differentiation, and that it has both neurotrophic and neuroprotective functions. In addition, in an extensive study on selective ANG-ALS variants we correlated the structural changes to the effects on neuronal survival and the ability to induce stress granules in neuronal cell lines. Furthermore, we have established that ANG-ALS variants which affect the structure of the catalytic site and either decrease or increase the RNase activity affect neuronal survival. Neuronal cell lines expressing the ANG-ALS variants also lack the ability to form stress granules. Here, we report a detailed experimental structural study on eleven new ANG-PD/ALS variants which will have implications in understanding the molecular basis underlying their role in PD and ALS.
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Affiliation(s)
- William J Bradshaw
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom
| | - Saima Rehman
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom
| | - Tram T K Pham
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom
| | - Nethaji Thiyagarajan
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom
| | - Rebecca L Lee
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom
| | - Vasanta Subramanian
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom
| | - K Ravi Acharya
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom
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4
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Perdios L, Lowe AR, Saladino G, Bunney TD, Thiyagarajan N, Alexandrov Y, Dunsby C, French PMW, Chin JW, Gervasio FL, Tate EW, Katan M. Conformational transition of FGFR kinase activation revealed by site-specific unnatural amino acid reporter and single molecule FRET. Sci Rep 2017; 7:39841. [PMID: 28045057 PMCID: PMC5206623 DOI: 10.1038/srep39841] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Accepted: 11/29/2016] [Indexed: 02/06/2023] Open
Abstract
Protein kinases share significant structural similarity; however, structural features alone are insufficient to explain their diverse functions. Thus, bridging the gap between static structure and function requires a more detailed understanding of their dynamic properties. For example, kinase activation may occur via a switch-like mechanism or by shifting a dynamic equilibrium between inactive and active states. Here, we utilize a combination of FRET and molecular dynamics (MD) simulations to probe the activation mechanism of the kinase domain of Fibroblast Growth Factor Receptor (FGFR). Using genetically-encoded, site-specific incorporation of unnatural amino acids in regions essential for activation, followed by specific labeling with fluorescent moieties, we generated a novel class of FRET-based reporter to monitor conformational differences corresponding to states sampled by non phosphorylated/inactive and phosphorylated/active forms of the kinase. Single molecule FRET analysis in vitro, combined with MD simulations, shows that for FGFR kinase, there are populations of inactive and active states separated by a high free energy barrier resulting in switch-like activation. Compared to recent studies, these findings support diversity in features of kinases that impact on their activation mechanisms. The properties of these FRET-based constructs will also allow further studies of kinase dynamics as well as applications in vivo.
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Affiliation(s)
- Louis Perdios
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St, London WC1E 6BT, UK
- Department of Chemistry, Imperial College London, South Kensington Campus, Exhibition Road, London SW7 2AZ, UK
| | - Alan R. Lowe
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St, London WC1E 6BT, UK
- London Centre for Nanotechnology, 17-19 Gower St, London, WC1H 0AH, UK
- Division of Biosciences, Birkbeck College, Malet St, London, WC1E 7HX, UK
| | - Giorgio Saladino
- Institute of Structural and Molecular Biology, Department of Chemistry, University College London, Gower St, London WC1E 6BT, UK
| | - Tom D. Bunney
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St, London WC1E 6BT, UK
| | - Nethaji Thiyagarajan
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St, London WC1E 6BT, UK
| | - Yuriy Alexandrov
- Department of Physics, Imperial College London, South Kensington Campus, Exhibition Road, London SW7 2AZ, UK
| | - Christopher Dunsby
- Department of Physics, Imperial College London, South Kensington Campus, Exhibition Road, London SW7 2AZ, UK
| | - Paul M. W. French
- Department of Physics, Imperial College London, South Kensington Campus, Exhibition Road, London SW7 2AZ, UK
| | - Jason W. Chin
- MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Francesco Luigi Gervasio
- Institute of Structural and Molecular Biology, Department of Chemistry, University College London, Gower St, London WC1E 6BT, UK
| | - Edward W. Tate
- Department of Chemistry, Imperial College London, South Kensington Campus, Exhibition Road, London SW7 2AZ, UK
| | - Matilda Katan
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St, London WC1E 6BT, UK
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5
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Patani H, Bunney TD, Thiyagarajan N, Norman RA, Ogg D, Breed J, Ashford P, Potterton A, Edwards M, Williams SV, Thomson GS, Pang CS, Knowles MA, Breeze AL, Orengo C, Phillips C, Katan M. Landscape of activating cancer mutations in FGFR kinases and their differential responses to inhibitors in clinical use. Oncotarget 2016; 7:24252-68. [PMID: 26992226 PMCID: PMC5029699 DOI: 10.18632/oncotarget.8132] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 02/28/2016] [Indexed: 01/09/2023] Open
Abstract
Frequent genetic alterations discovered in FGFRs and evidence implicating some as drivers in diverse tumors has been accompanied by rapid progress in targeting FGFRs for anticancer treatments. Wider assessment of the impact of genetic changes on the activation state and drug responses is needed to better link the genomic data and treatment options. We here apply a direct comparative and comprehensive analysis of FGFR3 kinase domain variants representing the diversity of point-mutations reported in this domain. We reinforce the importance of N540K and K650E and establish that not all highly activating mutations (for example R669G) occur at high-frequency and conversely, that some "hotspots" may not be linked to activation. Further structural characterization consolidates a mechanistic view of FGFR kinase activation and extends insights into drug binding. Importantly, using several inhibitors of particular clinical interest (AZD4547, BGJ-398, TKI258, JNJ42756493 and AP24534), we find that some activating mutations (including different replacements of the same residue) result in distinct changes in their efficacy. Considering that there is no approved inhibitor for anticancer treatments based on FGFR-targeting, this information will be immediately translatable to ongoing clinical trials.
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Affiliation(s)
- Harshnira Patani
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St, London WC1E 6BT, UK
| | - Tom D. Bunney
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St, London WC1E 6BT, UK
| | - Nethaji Thiyagarajan
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St, London WC1E 6BT, UK
| | - Richard A. Norman
- Discovery Sciences, AstraZeneca, Mereside, Alderley Park, Macclesfield, Cheshire SK10 4TG, UK
| | - Derek Ogg
- Discovery Sciences, AstraZeneca, Mereside, Alderley Park, Macclesfield, Cheshire SK10 4TG, UK
| | - Jason Breed
- Discovery Sciences, AstraZeneca, Mereside, Alderley Park, Macclesfield, Cheshire SK10 4TG, UK
| | - Paul Ashford
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St, London WC1E 6BT, UK
| | - Andrew Potterton
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St, London WC1E 6BT, UK
| | - Mina Edwards
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St, London WC1E 6BT, UK
| | - Sarah V. Williams
- Section of Experimental Oncology, Leeds Institute of Molecular Medicine, St James's University Hospital, Leeds LS9 7TF, UK
| | - Gary S. Thomson
- Astbury Centre for Structural Molecular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Camilla S.M. Pang
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St, London WC1E 6BT, UK
| | - Margaret A. Knowles
- Section of Experimental Oncology, Leeds Institute of Molecular Medicine, St James's University Hospital, Leeds LS9 7TF, UK
| | - Alexander L. Breeze
- Astbury Centre for Structural Molecular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Christine Orengo
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St, London WC1E 6BT, UK
| | - Chris Phillips
- Discovery Sciences, AstraZeneca, Mereside, Alderley Park, Macclesfield, Cheshire SK10 4TG, UK
| | - Matilda Katan
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St, London WC1E 6BT, UK
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6
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Bunney TD, Wan S, Thiyagarajan N, Sutto L, Williams SV, Ashford P, Koss H, Knowles MA, Gervasio FL, Coveney PV, Katan M. The Effect of Mutations on Drug Sensitivity and Kinase Activity of Fibroblast Growth Factor Receptors: A Combined Experimental and Theoretical Study. EBioMedicine 2015; 2:194-204. [PMID: 26097890 PMCID: PMC4471147 DOI: 10.1016/j.ebiom.2015.02.009] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Revised: 02/11/2015] [Accepted: 02/13/2015] [Indexed: 12/13/2022] Open
Abstract
Fibroblast growth factor receptors (FGFRs) are recognized therapeutic targets in cancer. We here describe insights underpinning the impact of mutations on FGFR1 and FGFR3 kinase activity and drug efficacy, using a combination of computational calculations and experimental approaches including cellular studies, X-ray crystallography and biophysical and biochemical measurements. Our findings reveal that some of the tested compounds, in particular TKI258, could provide therapeutic opportunity not only for patients with primary alterations in FGFR but also for acquired resistance due to the gatekeeper mutation. The accuracy of the computational methodologies applied here shows a potential for their wider application in studies of drug binding and in assessments of functional and mechanistic impacts of mutations, thus assisting efforts in precision medicine.
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Affiliation(s)
- Tom D. Bunney
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St., London WC1E 6BT, UK
| | - Shunzhou Wan
- Centre for Computational Science, Department of Chemistry, University College London, 20 Gordon St., London WC1H 0AJ, UK
| | - Nethaji Thiyagarajan
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St., London WC1E 6BT, UK
| | - Ludovico Sutto
- Institute of Structural and Molecular Biology, Department of Chemistry, University College London, Gower St., London WC1E 6BT, UK
| | - Sarah V. Williams
- Section of Experimental Oncology, Leeds Institute of Molecular Medicine, St James's University Hospital, Beckett Street, Leeds LS9 7TF, UK
| | - Paul Ashford
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St., London WC1E 6BT, UK
| | - Hans Koss
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St., London WC1E 6BT, UK
- Division of Molecular Structure, MRC-National Institute for Medical Research, Mill Hill, London NW7 1AA, UK
| | - Margaret A. Knowles
- Section of Experimental Oncology, Leeds Institute of Molecular Medicine, St James's University Hospital, Beckett Street, Leeds LS9 7TF, UK
| | - Francesco L. Gervasio
- Institute of Structural and Molecular Biology, Department of Chemistry, University College London, Gower St., London WC1E 6BT, UK
| | - Peter V. Coveney
- Centre for Computational Science, Department of Chemistry, University College London, 20 Gordon St., London WC1H 0AJ, UK
| | - Matilda Katan
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower St., London WC1E 6BT, UK
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7
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Bradshaw WJ, Kirby JM, Thiyagarajan N, Chambers CJ, Davies AH, Roberts AK, Shone CC, Acharya KR. The structure of the cysteine protease and lectin-like domains of Cwp84, a surface layer-associated protein from Clostridium difficile. Acta Crystallogr D Biol Crystallogr 2014; 70:1983-93. [PMID: 25004975 PMCID: PMC4089489 DOI: 10.1107/s1399004714009997] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Accepted: 05/03/2014] [Indexed: 01/05/2023]
Abstract
Clostridium difficile is a major problem as an aetiological agent for antibiotic-associated diarrhoea. The mechanism by which the bacterium colonizes the gut during infection is poorly understood, but undoubtedly involves a myriad of components present on the bacterial surface. The mechanism of C. difficile surface-layer (S-layer) biogenesis is also largely unknown but involves the post-translational cleavage of a single polypeptide (surface-layer protein A; SlpA) into low- and high-molecular-weight subunits by Cwp84, a surface-located cysteine protease. Here, the first crystal structure of the surface protein Cwp84 is described at 1.4 Å resolution and the key structural components are identified. The truncated Cwp84 active-site mutant (amino-acid residues 33-497; C116A) exhibits three regions: a cleavable propeptide and a cysteine protease domain which exhibits a cathepsin L-like fold followed by a newly identified putative carbohydrate-binding domain with a bound calcium ion, which is referred to here as a lectin-like domain. This study thus provides the first structural insights into Cwp84 and a strong base to elucidate its role in the C. difficile S-layer maturation mechanism.
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Affiliation(s)
- William J. Bradshaw
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, England
- Public Health England, Porton Down, Salisbury SP4 0JG, England
| | | | - Nethaji Thiyagarajan
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, England
| | - Christopher J. Chambers
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, England
- Public Health England, Porton Down, Salisbury SP4 0JG, England
| | - Abigail H. Davies
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, England
- Public Health England, Porton Down, Salisbury SP4 0JG, England
| | | | | | - K. Ravi Acharya
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, England
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8
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Pham TTK, Stinson B, Thiyagarajan N, Lizotte-Waniewski M, Brew K, Acharya KR. Structures of complexes of a metal-independent glycosyltransferase GT6 from Bacteroides ovatus with UDP-N-acetylgalactosamine (UDP-GalNAc) and its hydrolysis products. J Biol Chem 2014; 289:8041-50. [PMID: 24459149 PMCID: PMC3961637 DOI: 10.1074/jbc.m113.545384] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mammalian members of glycosyltransferase family 6 (GT6) of the CAZy database have a GT-A fold containing a conserved Asp-X-Asp (DXD) sequence that binds an essential metal cofactor. Bacteroides ovatus GT6a represents a GT6 clade found in more than 30 Gram-negative bacteria that is similar in sequence to the catalytic domains of mammalian GT6, but has an Asn95-Ala-Asn97 (NXN) sequence substituted for the DXD motif and metal-independent catalytic activity. Co-crystals of a low activity mutant of BoGT6a (E192Q) with UDP-GalNAc contained protein complexes with intact UDP-GalNAc and two forms with hydrolysis products (UDP plus GalNAc) representing an initial closed complex and later open form primed for product release. Two cationic residues near the C terminus of BoGT6a, Lys231 and Arg243, interact with the diphosphate moiety of UDP-GalNAc, but only Lys231 interacts with the UDP product and may function in leaving group stabilization. The amide group of Asn95, the first Asn of the NXN motif, interacts with the ribose moiety of the substrate. This metal-independent GT6 resembles its metal-dependent homologs in undergoing conformational changes on binding UDP-GalNAc that arise from structuring the C terminus to cover this substrate. It appears that in the GT6 family, the metal cofactor functions specifically in binding the UDP moiety in the donor substrate and transition state, actions that can be efficiently performed by components of the polypeptide chain.
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Affiliation(s)
- Tram T K Pham
- From the Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom and
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9
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Thiyagarajan N, Acharya KR. Crystal structure of human angiogenin with an engineered loop exhibits conformational flexibility at the functional regions of the molecule. FEBS Open Bio 2012; 3:65-70. [PMID: 23772376 PMCID: PMC3668512 DOI: 10.1016/j.fob.2012.12.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Revised: 12/19/2012] [Accepted: 12/19/2012] [Indexed: 11/18/2022] Open
Abstract
Human angiogenin (ANG) is an angiogenic molecule and a ribonucleolytic enzyme with significant amino acid sequence identity to pancreatic RNase A, plays a critical role in the establishment and growth of tumours. An association between ANG and cancer has been observed in more than 25 clinical studies to date. In addition, ANG has now been shown to be implicated in Amyotrophic Lateral Sclerosis (ALS) and Parkinson's Disease (PD). Structural and biochemical studies so far have showed several distinguishing features of ANG molecule compared to RNase A and provided details of the putative cell binding site, active site, nuclear translocation sequence and the roles of residues in binding and cleaving RNA. A key finding elucidated from the structural study on ANG is the presence of a 'blocked' C-terminus (part of the active site apparatus) compared with RNase A. Here we report the crystal structure of ANG with an 'engineered-loop' from eosinophil derived neurotoxin (a homologue of ANG) which has resulted with local perturbations (conformational flexibility) at the cell binding site and at the C-terminus of the molecule. This experimental observation will now provide a new avenue to design compounds (potent inhibitors) through a structure guided drug design route.
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Affiliation(s)
| | - K. Ravi Acharya
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, UK
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10
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Thiyagarajan N, Pham TTK, Stinson B, Sundriyal A, Tumbale P, Lizotte-Waniewski M, Brew K, Acharya KR. Structure of a metal-independent bacterial glycosyltransferase that catalyzes the synthesis of histo-blood group A antigen. Sci Rep 2012; 2:940. [PMID: 23230506 PMCID: PMC3516806 DOI: 10.1038/srep00940] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Accepted: 11/16/2012] [Indexed: 11/09/2022] Open
Abstract
Histo-blood group antigens (HBGAs) are a source of antigenic variation between individuals that modulates resistance and susceptibility to pathogens and is a barrier to the spread of enveloped viruses. HBGAs are also produced by a few prokaryotes where they are synthesized by glycosyltransferases (GTs) related to human HBGA synthases. Here we report the first structure of a bacterial GT of this family, from an intestinal resident, Bacteroides ovatus. Unlike its mammalian homologues and other GTs with similar folds, this protein lacks a metal-binding Asp-X-Asp motif and is fully active in the absence of divalent metal ions, yet is strikingly similar in structure and in its interactions with substrates to structurally characterized mammalian metal-dependent mammalian homologues. This shows how an apparently major divergence in catalytic properties can be accommodated by minor structural adjustments and illustrates the structural underpinnings of horizontal transfer of a functional gene from prokaryotes to vertebrates.
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Affiliation(s)
- Nethaji Thiyagarajan
- Department of Biology and Biochemistry, University of Bath , Claverton Down, Bath BA2 7AY, UK
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11
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Vaiyapuri S, Thiyagarajan N, Hutchinson EG, Gibbins JM. Sequence and phylogenetic analysis of viper venom serine proteases. Bioinformation 2012; 8:763-72. [PMID: 23055627 PMCID: PMC3449387 DOI: 10.6026/97320630008763] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2012] [Accepted: 08/02/2012] [Indexed: 11/23/2022] Open
Abstract
Snakebites are a major neglected tropical disease responsible for as many as 95000 deaths every year worldwide. Viper venom serine proteases disrupt haemostasis of prey and victims by affecting various stages of the blood coagulation system. A better understanding of their sequence, structure, function and phylogenetic relationships will improve the knowledge on the pathological conditions and aid in the development of novel therapeutics for treating snakebites. A large dataset for all available viper venom serine proteases was developed and analysed to study various features of these enzymes. Despite the large number of venom serine protease sequences available, only a small proportion of these have been functionally characterised. Although, they share some of the common features such as a C-terminal extension, GWG motif and disulphide linkages, they vary widely between each other in features such as isoelectric points, potential N-glycosylation sites and functional characteristics. Some of the serine proteases contain substitutions for one or more of the critical residues in catalytic triad or primary specificity pockets. Phylogenetic analysis clustered all the sequences in three major groups. The sequences with substitutions in catalytic triad or specificity pocket clustered together in separate groups. Our study provides the most complete information on viper venom serine proteases to date and improves the current knowledge on the sequence, structure, function and phylogenetic relationships of these enzymes. This collective analysis of venom serine proteases will help in understanding the complexity of envenomation and potential therapeutic avenues.
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Affiliation(s)
- Sakthivel Vaiyapuri
- Institute for Cardiovascular and Metabolic Research, University of Reading, Reading, United Kingdom
| | - Nethaji Thiyagarajan
- Department of Biology and Biochemistry, University of Bath, Bath, United Kingdom
| | - E Gail Hutchinson
- Institute for Cardiovascular and Metabolic Research, University of Reading, Reading, United Kingdom
| | - Jonathan M Gibbins
- Institute for Cardiovascular and Metabolic Research, University of Reading, Reading, United Kingdom
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12
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Vaiyapuri S, Thiyagarajan N, Hutchinson EG, Gibbins JM. Sequence and phylogenetic analysis of viper venom serine proteases. Bioinformation 2012. [DOI: 10.6026/97320630008563] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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13
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Kirby JM, Thiyagarajan N, Roberts AK, Shone CC, Acharya KR. Expression, purification, crystallization and preliminary crystallographic analysis of a putative Clostridium difficile surface protein Cwp19. Acta Crystallogr Sect F Struct Biol Cryst Commun 2011; 67:762-7. [PMID: 21795789 PMCID: PMC3144791 DOI: 10.1107/s1744309111016770] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Accepted: 05/03/2011] [Indexed: 11/15/2022]
Abstract
Cwp19 is a putatively surface-located protein from Clostridium difficile. A recombinant N-terminal protein (residues 27-401) lacking the signal peptide and the C-terminal cell-wall-binding repeats (PFam04122) was crystallized using the sitting-drop vapour-diffusion method and diffracted to 2 Å resolution. The crystal appeared to belong to the primitive monoclinic space group P2(1), with unit-cell parameters a=109.1, b=61.2, c=109.2 Å, β=111.85°, and is estimated to contain two molecules of Cwp19 per asymmetric unit.
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Affiliation(s)
- Jonathan M. Kirby
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, England
- Research Department, Health Protection Agency, Porton Down, Salisbury SP4 0JG, England
| | - Nethaji Thiyagarajan
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, England
| | - April K. Roberts
- Research Department, Health Protection Agency, Porton Down, Salisbury SP4 0JG, England
| | - Clifford C. Shone
- Research Department, Health Protection Agency, Porton Down, Salisbury SP4 0JG, England
| | - K. Ravi Acharya
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, England
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14
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Abstract
Molecular probes are useful for both studying and controlling the functions of enzymes and other proteins. The most useful probes have high affinity for their target, along with small size and resistance to degradation. Here, we report on new surrogates for nucleic acids that fulfill these criteria. Isosteres in which phosphoryl [R–O–P(O2−)–O–R′] groups are replaced with N-acylsulfonamidyl [R–C(O)–N−–S(O2)–R′] or sulfonimidyl [R–S(O2)–N−–S(O2)–R′] groups increase the number of nonbridging oxygens from two (phosphoryl) to three (N-acylsulfonamidyl) or four (sulfonimidyl). Six such isosteres were found to be more potent inhibitors of catalysis by bovine pancreatic RNase A than are parent compounds containing phosphoryl groups. The atomic structures of two RNase A·N-acylsulfonamide complexes were determined at high resolution by X-ray crystallography. The N-acylsulfonamidyl groups were observed to form more hydrogen bonds with active site residues than did the phosphoryl groups in analogous complexes. These data encourage the further development and use of N-acylsulfonamides and sulfonimides as antagonists of nucleic acid-binding proteins.
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15
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Cozier GE, Leese MP, Lloyd MD, Baker MD, Thiyagarajan N, Acharya KR, Potter BVL. Structures of Human Carbonic Anhydrase II/Inhibitor Complexes Reveal a Second Binding Site for Steroidal and Nonsteroidal Inhibitors,. Biochemistry 2010; 49:3464-76. [DOI: 10.1021/bi902178w] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Gyles E. Cozier
- Medicinal Chemistry, Department of Pharmacy and Pharmacology
| | - Mathew P. Leese
- Medicinal Chemistry, Department of Pharmacy and Pharmacology
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16
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Leese MP, Jourdan F, Kimberley MR, Cozier GE, Thiyagarajan N, Stengel C, Regis-Lydi S, Foster PA, Newman SP, Acharya KR, Ferrandis E, Purohit A, Reed MJ, Potter BVL. Chimeric microtubule disruptors. Chem Commun (Camb) 2010; 46:2907-9. [DOI: 10.1039/c002558e] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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17
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Mitsiki E, Papageorgiou AC, Iyer S, Thiyagarajan N, Prior SH, Sleep D, Finnis C, Acharya KR. Structures of native human thymidine phosphorylase and in complex with 5-iodouracil. Biochem Biophys Res Commun 2009; 386:666-70. [PMID: 19555658 PMCID: PMC2719695 DOI: 10.1016/j.bbrc.2009.06.104] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2009] [Accepted: 06/19/2009] [Indexed: 11/28/2022]
Abstract
Thymidine phosphorylase (TP) first identified as platelet derived endothelial cell growth factor (PD-ECGF) plays a key role in nucleoside metabolism. Human TP (hTP) is implicated in angiogenesis and is overexpressed in several solid tumors. Here, we report the crystal structures of recombinant hTP and its complex with a substrate 5-iodouracil (5IUR) at 3.0 and 2.5A, respectively. In addition, we provide information on the role of specific residues in the enzymatic activity of hTP through mutagenesis and kinetic studies.
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Affiliation(s)
- Eirini Mitsiki
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, UK
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18
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Jamaluddin H, Tumbale P, Ferns TA, Thiyagarajan N, Brew K, Acharya KR. Crystal structure of alpha-1,3-galactosyltransferase (alpha3GT) in a complex with p-nitrophenyl-beta-galactoside (pNPbetaGal). Biochem Biophys Res Commun 2009; 385:601-4. [PMID: 19486884 DOI: 10.1016/j.bbrc.2009.05.111] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2009] [Accepted: 05/26/2009] [Indexed: 01/19/2023]
Abstract
The specificities of glycosyltransferases make them useful for the synthesis of biologically active oligosaccharides, but also restrict their range of products. In substrate engineering, substrate promiscuity is enhanced by attaching removable interactive groups to weak substrates. Thus, the attachment of betap-nitrophenyl converts galactose from a poor into a good substrate of alpha-1,3-galactosyltransferase. The crystallographic structure of a complex of alpha3GT containing p-nitrophenyl-beta-galactoside shows that the p-nitrophenyl binds similarly to the N-acetylglucosamine of the substrate, N-acetyllactosamine, interacting with the indole of Trp249. p-Nitrophenyl, unlike N-acetylglucosamine, makes no H-bonds but has more non-polar interactions, making it an effective monosaccharide mimetic.
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Affiliation(s)
- Haryati Jamaluddin
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA27AY, UK
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19
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Masuyer G, Thiyagarajan N, James PL, Marks PMH, Chaddock JA, Acharya KR. Crystal structure of a catalytically active, non-toxic endopeptidase derivative of Clostridium botulinum toxin A. Biochem Biophys Res Commun 2009; 381:50-3. [PMID: 19351593 DOI: 10.1016/j.bbrc.2009.02.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2009] [Accepted: 02/02/2009] [Indexed: 11/15/2022]
Abstract
Botulinum neurotoxins (BoNTs) modulate cholinergic nerve terminals to result in neurotransmitter blockade. BoNTs consists of catalytic (LC), translocation (Hn) and cell-binding domains (Hc). The binding function of the Hc domain is essential for BoNTs to bind the neuronal cell membrane, therefore, removal of the Hc domain results in a product that retains the endopeptidase activity of the LC but is non-toxic. Thus, a molecule consisting of LC and Hn domains of BoNTs, termed LHn, is a suitable molecule for engineering novel therapeutics. The structure of LHA at 2.6 A reported here provides an understanding of the structural implications and challenges of engineering therapeutic molecules that combine functional properties of LHn of BoNTs with specific ligand partners to target different cell types.
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Affiliation(s)
- Geoffrey Masuyer
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, UK
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20
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Ulrich M, Petre A, Youhnovski N, Prömm F, Schirle M, Schumm M, Pero RS, Doyle A, Checkel J, Kita H, Thiyagarajan N, Acharya KR, Schmid-Grendelmeier P, Simon HU, Schwarz H, Tsutsui M, Shimokawa H, Bellon G, Lee JJ, Przybylski M, Döring G. Post-translational tyrosine nitration of eosinophil granule toxins mediated by eosinophil peroxidase. J Biol Chem 2008; 283:28629-40. [PMID: 18694936 PMCID: PMC2661412 DOI: 10.1074/jbc.m801196200] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2008] [Revised: 07/14/2008] [Indexed: 11/06/2022] Open
Abstract
Nitration of tyrosine residues has been observed during various acute and chronic inflammatory diseases. However, the mechanism of tyrosine nitration and the nature of the proteins that become tyrosine nitrated during inflammation remain unclear. Here we show that eosinophils but not other cell types including neutrophils contain nitrotyrosine-positive proteins in specific granules. Furthermore, we demonstrate that the human eosinophil toxins, eosinophil peroxidase (EPO), major basic protein, eosinophil-derived neurotoxin (EDN) and eosinophil cationic protein (ECP), and the respective murine toxins, are post-translationally modified by nitration at tyrosine residues during cell maturation. High resolution affinity-mass spectrometry identified specific single nitration sites at Tyr349 in EPO and Tyr33 in both ECP and EDN. ECP and EDN crystal structures revealed and EPO structure modeling suggested that the nitrated tyrosine residues in the toxins are surface exposed. Studies in EPO(-/-), gp91phox(-/-), and NOS(-/-) mice revealed that tyrosine nitration of these toxins is mediated by EPO in the presence of hydrogen peroxide and minute amounts of NOx. Tyrosine nitration of eosinophil granule toxins occurs during maturation of eosinophils, independent of inflammation. These results provide evidence that post-translational tyrosine nitration is unique to eosinophils.
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Affiliation(s)
- Martina Ulrich
- Institute of Medical Microbiology and Hygiene, Universitätsklinikum Tübingen, Tübingen 72074, Germany
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21
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Tumbale P, Jamaluddin H, Thiyagarajan N, Acharya KR, Brew K. Screening a limited structure-based library identifies UDP-GalNAc-specific mutants of alpha-1,3-galactosyltransferase. Glycobiology 2008; 18:1036-43. [PMID: 18782853 DOI: 10.1093/glycob/cwn083] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Complex glycans have important roles in biological recognition processes and considerable pharmaceutical potential. The synthesis of novel glycans can be facilitated by engineering glycosyltransferases to modify their substrate specificities. The choice of sites to modify requires the knowledge of the structures of enzyme-substrate complexes while the complexity of protein structures necessitates the exploration of a large array of multisite mutations. The retaining glycosyltransferase, alpha-1,3-galactosyltransferase (alpha3GT), which catalyzes the synthesis of the alpha-Gal epitope, has strict specificity for UDP-galactose as a donor substrate. Based on the structure of a complex of UDP-galactose with alpha3GT, the specificity for the galactose moiety can be partly attributed to residues that interact with the galactose 2-OH group, particularly His280 and Ala282. With the goal of engineering a variant of bovine alpha3GT with GalNAc transferase activity, we constructed a limited library of 456 alpha3GT mutants containing 19 alternative amino acids at position 280, two each at 281 and 282 and six at position 283. Clones (1500) were screened by assaying partially purified bacterially expressed variants for GalNAc transferase activity. Mutants with the highest levels of GalNAc transferase activity, AGGL or GGGL, had substitutions at all four sites. The AGGL mutant had slightly superior GalNAc transferase activity amounting to about 3% of the activity of the wild-type enzyme with UDP-Gal. This mutant had a low activity with UDP-Gal; its crystallographic structure suggests that the smaller side chains at residues 280-282 form a pocket to accommodate the larger acetamido group of GalNAc. Mutational studies indicate that Leu283 is important for stability in this mutant.
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Affiliation(s)
- Percy Tumbale
- Department of Biomedical Science, College of Biomedical Science, Florida Atlantic University, Glades Road, Boca Raton, FL 33431, USA
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22
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Tumbale P, Jamaluddin H, Thiyagarajan N, Brew K, Acharya KR. Structural basis of UDP-galactose binding by alpha-1,3-galactosyltransferase (alpha3GT): role of negative charge on aspartic acid 316 in structure and activity. Biochemistry 2008; 47:8711-8. [PMID: 18651752 DOI: 10.1021/bi800852a] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
alpha-1,3-Galactosyltransferase (alpha3GT) catalyzes the transfer of galactose from UDP-galactose to form an alpha 1-3 link with beta-linked galactosides; it is part of a family of homologous retaining glycosyltransferases that includes the histo-blood group A and B glycosyltransferases, Forssman glycolipid synthase, iGb3 synthase, and some uncharacterized prokaryotic glycosyltransferases. In mammals, the presence or absence of active forms of these enzymes results in antigenic differences between individuals and species that modulate the interplay between the immune system and pathogens. The catalytic mechanism of alpha3GT is controversial, but the structure of an enzyme complex with the donor substrate could illuminate both this and the basis of donor substrate specificity. We report here the structure of the complex of a low-activity mutant alpha3GT with UDP-galactose (UDP-gal) exhibiting a bent configuration stabilized by interactions of the galactose with multiple residues in the enzyme including those in a highly conserved region (His315 to Ser318). Analysis of the properties of mutants containing substitutions for these residues shows that catalytic activity is strongly affected by His315 and Asp316. The negative charge of Asp316 is crucial for catalytic activity, and structural studies of two mutants show that its interaction with Arg202 is needed for an active site structure that facilitates the binding of UDP-gal in a catalytically competent conformation.
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Affiliation(s)
- Percy Tumbale
- Department of Biomedical Science, Florida Atlantic University, 777 Glades Road, Boca Raton, Florida 33431, USA
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23
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Crabtree B, Thiyagarajan N, Prior SH, Wilson P, Iyer S, Ferns T, Shapiro R, Brew K, Subramanian V, Acharya KR. Characterization of Human Angiogenin Variants Implicated in Amyotrophic Lateral Sclerosis. Biochemistry 2007; 46:11810-8. [PMID: 17900154 DOI: 10.1021/bi701333h] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Human angiogenin (ANG), the first member of the angiogenin family (from the pancreatic ribonuclease A superfamily) to be identified, is an angiogenic factor that induces neovascularization. It has received much attention due to its involvement in the growth of tumors and its elevated expression level in pancreatic and several other cancers. Recently the biological role of ANG has been shown to extend to the nervous system. Mutations in ANG have been linked with familial as well as sporadic forms of amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disorder characterized by selective destruction of motor neurons. Furthermore, mouse angiogenin-1 has been shown to be expressed in the developing nervous system and during the neuronal differentiation of pluripotent stem cells. We have now characterized the seven variants of ANG reported in ALS patients with respect to the known biochemical properties of ANG and further studied the biological properties of three of these variants. Our results show that the ribonucleolytic activity of six of the seven ANG-ALS implicated variants is significantly reduced or lost and some variants also show altered thermal stability. We report a significant reduction in the cell proliferative and angiogenic activities of the three variants that we chose to investigate further. Our studies on the biochemical and structural features of these ANG variants now form the basis for further investigations to determine their role(s) in ALS.
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Affiliation(s)
- Benedict Crabtree
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom
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24
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Lloyd MD, Thiyagarajan N, Ho YT, Woo LWL, Sutcliffe OB, Purohit A, Reed MJ, Acharya KR, Potter BVL. First Crystal Structures of Human Carbonic Anhydrase II in Complex with Dual Aromatase−Steroid Sulfatase Inhibitors,. Biochemistry 2005; 44:6858-66. [PMID: 15865431 DOI: 10.1021/bi047692e] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Carbonic anhydrase (CA) catalyzes the reversible hydration of carbon dioxide to hydrogen carbonate. The role of CA in maintaining pH balance has made it an attractive drug target for the treatment of cancer, and it has recently been implicated in the delivery of sulfamate-containing drugs. With the acceptance of steroid sulfatase as a target for hormone-dependent cancer, novel dual aromatase-steroid sulfatase inhibitors (DASIs) containing a sulfamate group are now being developed. In this study, we show that CA II is potently inhibited by several members of this class of inhibitor. The structures of CA II complexed with 4-[(4-O-sulfamoylbenzyl)(4-cyanophenyl)amino]-4H-[1,2,4]triazole (K(D) = 84 +/- 5 nM) and 4-[(3-bromo-4-O-sulfamoylbenzyl)(4-cyanophenyl)amino]-4H-[1,2,4]triazole (K(D) = 454 +/- 29 nM) are reported to 2.02 and 1.76 A, respectively. Both inhibitors ligate to the active site zinc(II) atom via their sulfamate nitrogen, while the rest of the molecule is contained within the hydrophobic binding pocket. Key protein residues include Val-121, Phe-131, Val-135, Val-143, Leu-141, Leu-198, Pro-202, and Leu-204. Despite being structurally similar, the two ligands experience different types of binding particularly in the sulfamate-containing aromatic ring and the opposite geometric arrangement of the triazole and cyanophenyl groups around the configurationally invertible central nitrogen atom. Small changes in inhibitor structure can cause large changes in binding to CA II, and this underlines the importance of structure-based drug design with this enzyme and other isoforms relevant to potential anticancer therapy. Moreover, these results underpin the idea that binding to erythrocyte CA II may be a general method of stabilizing and delivering sulfamate-based drugs in vivo.
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Affiliation(s)
- Matthew D Lloyd
- Medicinal Chemistry, Department of Pharmacy and Pharmacology, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom.
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25
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Abstract
2'-Fluoro-2'-deoxyuridine 3'-phosphate (dU(F)MP) and arabinouridine 3'-phosphate (araUMP) have non-natural furanose rings. dU(F)MP and araUMP were prepared by chemical synthesis and found to have three- to sevenfold higher affinity than uridine 3'-phosphate (3'-UMP) or 2'-deoxyuridine 3'-phosphate (dUMP) for ribonuclease A (RNase A). These differences probably arise (in part) from the phosphoryl groups of 3'-UMP, dU(F)MP, and araUMP (pK(a) = 5.9) being more anionic than that of dUMP (pK(a) = 6.3). The three-dimensional structures of the crystalline complexes of RNase A with dUMP, dU(F)MP and araUMP were determined at < 1.7 A resolution by X-ray diffraction analysis. In these three structures, the uracil nucleobases and phosphoryl groups bind to the enzyme in a nearly identical position. Unlike 3'-UMP and dU(F)MP, dUMP and araUMP bind with their furanose rings in the preferred pucker. In the RNase A.araUMP complex, the 2'-hydroxyl group is exposed to the solvent. All four 3'-nucleotides bind more tightly to wild-type RNase A than to its T45G variant, which lacks the residue that interacts most closely with the uracil nucleobase. These findings illuminate in atomic detail the interaction of RNase A and 3'-nucleotides, and indicate that non-natural furanose rings can serve as the basis for more potent inhibitors of catalysis by RNase A.
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Affiliation(s)
- Cara L Jenkins
- Department of Chemistry, University of Wisconsin-Madison, WI, USA
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Turton K, Natesh R, Thiyagarajan N, Chaddock JA, Acharya KR. Crystal structures of Erythrina cristagalli lectin with bound N-linked oligosaccharide and lactose. Glycobiology 2004; 14:923-9. [PMID: 15201215 DOI: 10.1093/glycob/cwh114] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Erythrina cristagalli lectin (ECL) is a galactose-specific legume lectin. Although its biological function in the legume is unknown, ECL exhibits hemagglutinating activity in vitro and is mitogenic for T lymphocytes. In addition, it has been recently shown that ECL forms a novel conjugate when coupled to a catalytically active derivative of the type A neurotoxin from Clostridium botulinum, thus providing a therapeutic potential. ECL is biologically active as a dimer in which each protomer contains a functional carbohydrate-combining site. The crystal structure of native ECL was recently reported in complex with lactose and 2'-fucosyllactose. ECL protomers adopt the legume lectin fold but form non-canonical dimers via the handshake motif as was previously observed for Erythrina corallodendron lectin. Here we report the crystal structures of native and recombinant forms of the lectin in three new crystal forms, both unliganded and in complex with lactose. For the first time, the detailed structure of the glycosylated hexasaccharide for native ECL has been elucidated. The structure also shows that in the crystal lattice the glycosylation site and the carbohydrate binding site are involved in intermolecular contacts through water-mediated interactions.
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Affiliation(s)
- Kathryn Turton
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom
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