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Wang X, Terrie L, Wu G, Van Damme EJM, Thorrez L, Fooks AR, Banyard AC, Jochmans D, Neyts J. Urtica dioica Agglutinin Prevents Rabies Virus Infection in a Muscle Explant Model. Pharmaceutics 2023; 15:pharmaceutics15051353. [PMID: 37242595 DOI: 10.3390/pharmaceutics15051353] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 03/06/2023] [Accepted: 04/26/2023] [Indexed: 05/28/2023] Open
Abstract
Infection with the rabies virus (RABV) results in a 100% lethal neurological disease once symptoms develop. Post-exposure prophylaxis (PEP) consists of a combination of vaccination and anti-rabies immunoglobulins (RIGs); it is 100% effective if administered early after exposure. Because of its limited availability, alternatives for RIGs are needed. To that end, we evaluated a panel of 33 different lectins for their effect on RABV infection in cell culture. Several lectins, with either mannose or GlcNAc specificity, elicited anti-RABV activity, of which the GlcNAc-specific Urtica dioica agglutinin (UDA) was selected for further studies. UDA was found to prevent the entry of the virus into the host cell. To further assess the potential of UDA, a physiologically relevant RABV infection muscle explant model was developed. Strips of dissected swine skeletal muscle that were kept in a culture medium could be productively infected with the RABV. When the infection of the muscle strips was carried out in the presence of UDA, RABV replication was completely prevented. Thus, we developed a physiologically relevant RABV muscle infection model. UDA (i) may serve as a reference for further studies and (ii) holds promise as a cheap and simple-to-produce alternative for RIGs in PEP.
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Affiliation(s)
- Xinyu Wang
- Department of Microbiology, Immunology and Transplantation, Rega Institute, KU Leuven, 3000 Leuven, Belgium
- Global Virus Network (GVN), Baltimore, MD 21201, USA
| | - Lisanne Terrie
- Tissue Engineering Lab, Department of Development and Regeneration, Campus Kulak, KU Leuven, 8500 Kortrijk, Belgium
| | - Guanghui Wu
- Animal and Plant Health Agency (APHA), Woodham Lane, Weybridge KT15 3NB, UK
| | - Els J M Van Damme
- Department of Biotechnology, Faculty of Bioscience Engineering, Ghent University, 9000 Gent, Belgium
| | - Lieven Thorrez
- Tissue Engineering Lab, Department of Development and Regeneration, Campus Kulak, KU Leuven, 8500 Kortrijk, Belgium
| | - Anthony R Fooks
- Animal and Plant Health Agency (APHA), Woodham Lane, Weybridge KT15 3NB, UK
| | - Ashley C Banyard
- Animal and Plant Health Agency (APHA), Woodham Lane, Weybridge KT15 3NB, UK
| | - Dirk Jochmans
- Department of Microbiology, Immunology and Transplantation, Rega Institute, KU Leuven, 3000 Leuven, Belgium
- Global Virus Network (GVN), Baltimore, MD 21201, USA
| | - Johan Neyts
- Department of Microbiology, Immunology and Transplantation, Rega Institute, KU Leuven, 3000 Leuven, Belgium
- Global Virus Network (GVN), Baltimore, MD 21201, USA
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2
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Samadian E, Colagar AH, Safarzad M, Asadi J, Mansouri K. Inhibitory potency of the nettle lectin on neovascularization: a biomolecule for carbohydrate-mediated targeting of angiogenesis. Mol Biol Rep 2023; 50:4491-4503. [PMID: 37024746 DOI: 10.1007/s11033-023-08355-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 02/22/2023] [Indexed: 04/08/2023]
Abstract
BACKGROUND Current angiogenesis inhibitors target cellular vascularization processes, including proliferation, migration, and tube formation. In this study, we investigated the impact of Urtica dioica agglutinin (UDA) on the cellular vascularization process. METHODS AND RESULTS Various concentrations of UDA were applied to normal (HUVEC, MCF-10 A, and HDF from humans, and L-929 from mice) and cancer (A431 and U87 from humans, and 4T1 from mice) cell lines at different times. The MTT, cell migration assay, differentiation of endothelial cells, expression of VEGF-A/VEGF-R2, and integrin α2 were evaluated. The MTT results demonstrated that UDA was non-toxic to normal cells while inhibiting the growth of neoplastic cells. The migratory capacity of HUVECs and U87 glioblastoma cells was inhibited by UDA in the wound repair model. This lectin inhibited HUVEC-induced vessel sprouting in the collagen-cytodex matrix. In addition, UDA treatment reduced VEGF-integrin cross-talk in HUVECs, confirming the anti-angiogenic activity of this molecule. CONCLUSIONS Based on our findings, UDA may have an effect on cancer cell proliferation and vascularization events while causing minimal toxicity to normal cells via binding glyco-conjugates containing GlcNAc/man oligomers like EGFR. This is a blue clue for the angiogenesis-related therapeutic importance of UDA.
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Affiliation(s)
- Esmaeil Samadian
- Department of Molecular and Cell Biology, Faculty of Basic Sciences, University of Mazandaran, Babolsar, 47416-95447, Iran
| | - Abasalt Hosseinzadeh Colagar
- Department of Molecular and Cell Biology, Faculty of Basic Sciences, University of Mazandaran, Babolsar, 47416-95447, Iran.
| | - Mahdieh Safarzad
- Metabolic Disorders Research Center, Golestan University of Medical Science, Gorgan, Iran
| | - Jahanbakhsh Asadi
- Metabolic Disorders Research Center, Golestan University of Medical Science, Gorgan, Iran
| | - Kamran Mansouri
- Medical Biology Research Center, Kermanshah University of Medical Sciences, Kermanshah, Iran
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3
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Vanhulle E, D’huys T, Provinciael B, Stroobants J, Camps A, Noppen S, Schols D, Van Damme EJM, Maes P, Stevaert A, Vermeire K. Carbohydrate-binding protein from stinging nettle as fusion inhibitor for SARS-CoV-2 variants of concern. Front Cell Infect Microbiol 2022; 12:989534. [PMID: 36111239 PMCID: PMC9468479 DOI: 10.3389/fcimb.2022.989534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Accepted: 08/09/2022] [Indexed: 11/13/2022] Open
Abstract
Urtica dioica agglutinin (UDA) is a carbohydrate-binding small monomeric protein isolated from stinging nettle rhizomes. It inhibits replication of a broad range of viruses, including coronaviruses, in multiple cell types, with appealing selectivity. In this work, we investigated the potential of UDA as a broad-spectrum antiviral agent against SARS-CoV-2. UDA potently blocks transduction of pseudotyped SARS-CoV-2 in A549.ACE2+-TMPRSS2 cells, with IC50 values ranging from 0.32 to 1.22 µM. Furthermore, UDA prevents viral replication of the early Wuhan-Hu-1 strain in Vero E6 cells (IC50 = 225 nM), but also the replication of SARS-CoV-2 variants of concern, including Alpha, Beta and Gamma (IC50 ranging from 115 to 171 nM). In addition, UDA exerts antiviral activity against the latest circulating Delta and Omicron variant in U87.ACE2+ cells (IC50 values are 1.6 and 0.9 µM, respectively). Importantly, when tested in Air-Liquid Interface (ALI) primary lung epithelial cell cultures, UDA preserves antiviral activity against SARS-CoV-2 (20A.EU2 variant) in the nanomolar range. Surface plasmon resonance (SPR) studies demonstrated a concentration-dependent binding of UDA to the viral spike protein of SARS-CoV-2, suggesting interference of UDA with cell attachment or subsequent virus entry. Moreover, in additional mechanistic studies with cell-cell fusion assays, UDA inhibited SARS-CoV-2 spike protein-mediated membrane fusion. Finally, pseudotyped SARS-CoV-2 mutants with N-glycosylation deletions in the S2 subunit of the spike protein remained sensitive to the antiviral activity of UDA. In conclusion, our data establish UDA as a potent fusion inhibitor for the current variants of SARS-CoV-2.
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Affiliation(s)
- Emiel Vanhulle
- Laboratory of Virology and Chemotherapy, Rega Institute, Department of Microbiology, Immunology and Transplantation, KU Leuven, Leuven, Belgium
| | - Thomas D’huys
- Laboratory of Virology and Chemotherapy, Rega Institute, Department of Microbiology, Immunology and Transplantation, KU Leuven, Leuven, Belgium
| | - Becky Provinciael
- Laboratory of Virology and Chemotherapy, Rega Institute, Department of Microbiology, Immunology and Transplantation, KU Leuven, Leuven, Belgium
| | - Joren Stroobants
- Laboratory of Virology and Chemotherapy, Rega Institute, Department of Microbiology, Immunology and Transplantation, KU Leuven, Leuven, Belgium
| | - Anita Camps
- Laboratory of Virology and Chemotherapy, Rega Institute, Department of Microbiology, Immunology and Transplantation, KU Leuven, Leuven, Belgium
| | - Sam Noppen
- Laboratory of Virology and Chemotherapy, Rega Institute, Department of Microbiology, Immunology and Transplantation, KU Leuven, Leuven, Belgium
| | - Dominique Schols
- Laboratory of Virology and Chemotherapy, Rega Institute, Department of Microbiology, Immunology and Transplantation, KU Leuven, Leuven, Belgium
| | - Els J. M. Van Damme
- Laboratory of Biochemistry and Glycobiology, Department of Biotechnology, Ghent University, Ghent, Belgium
| | - Piet Maes
- Laboratory of Clinical and Epidemiological Virology, Rega Institute, Department of Microbiology, Immunology and Transplantation, KU Leuven, Leuven, Belgium
| | - Annelies Stevaert
- Laboratory of Virology and Chemotherapy, Rega Institute, Department of Microbiology, Immunology and Transplantation, KU Leuven, Leuven, Belgium
| | - Kurt Vermeire
- Laboratory of Virology and Chemotherapy, Rega Institute, Department of Microbiology, Immunology and Transplantation, KU Leuven, Leuven, Belgium
- *Correspondence: Kurt Vermeire,
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4
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Nabi-Afjadi M, Heydari M, Zalpoor H, Arman I, Sadoughi A, Sahami P, Aghazadeh S. Lectins and lectibodies: potential promising antiviral agents. Cell Mol Biol Lett 2022; 27:37. [PMID: 35562647 PMCID: PMC9100318 DOI: 10.1186/s11658-022-00338-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 04/21/2022] [Indexed: 12/30/2022] Open
Abstract
In nature, lectins are widely dispersed proteins that selectively recognize and bind to carbohydrates and glycoconjugates via reversible bonds at specific binding sites. Many viral diseases have been treated with lectins due to their wide range of structures, specificity for carbohydrates, and ability to bind carbohydrates. Through hemagglutination assays, these proteins can be detected interacting with various carbohydrates on the surface of cells and viral envelopes. This review discusses the most robust lectins and their rationally engineered versions, such as lectibodies, as antiviral proteins. Fusion of lectin and antibody’s crystallizable fragment (Fc) of immunoglobulin G (IgG) produces a molecule called a “lectibody” that can act as a carbohydrate-targeting antibody. Lectibodies can not only bind to the surface glycoproteins via their lectins and neutralize and clear viruses or infected cells by viruses but also perform Fc-mediated antibody effector functions. These functions include complement-dependent cytotoxicity (CDC), antibody-dependent cell-mediated cytotoxicity (ADCC), and antibody-dependent cell-mediated phagocytosis (ADCP). In addition to entering host cells, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein S1 binds to angiotensin-converting enzyme 2 (ACE2) and downregulates it and type I interferons in a way that may lead to lung disease. The SARS-CoV-2 spike protein S1 and human immunodeficiency virus (HIV) envelope are heavily glycosylated, which could make them a major target for developing vaccines, diagnostic tests, and therapeutic drugs. Lectibodies can lead to neutralization and clearance of viruses and cells infected by viruses by binding to glycans located on the envelope surface (e.g., the heavily glycosylated SARS-CoV-2 spike protein).
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Affiliation(s)
- Mohsen Nabi-Afjadi
- Department of Biochemistry, Faculty of Biological Science, Tarbiat Modares University, Tehran, Iran
| | - Morteza Heydari
- Institute of Biochemistry and Biophysics, University of Tehran, Tehran, 13145-1384, Iran
| | - Hamidreza Zalpoor
- Shiraz Neuroscience Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.,Network of Immunity in Infection, Malignancy and Autoimmunity (NIIMA), Universal Scientific Education and Research Network (USERN), Tehran, Iran.,American Association of Kidney Patients, Tampa, FL, USA
| | - Ibrahim Arman
- Department of Molecular Biology and Genetics, Faculty of Sciences and Arts, Zonguldak Bulent Ecevit University, Zonguldak, Turkey
| | - Arezoo Sadoughi
- Department of Immunology, International Campus, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Parisa Sahami
- Medical Biology Research Center, Health Technologies Institute, Kermanshah University of Medical Sciences (KUMS), Kermanshah, Iran
| | - Safiyeh Aghazadeh
- Division of Biochemistry, Department of Basic Sciences, Faculty of Veterinary Medicine, Urmia University, Urmia, 5756151818, Iran.
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5
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Konozy E, Osman M, Dirar A. Plant Lectins as Potent Anti-coronaviruses, Anti-inflammatory, Antinociceptive and Antiulcer Agents. Saudi J Biol Sci 2022; 29:103301. [PMID: 35475119 PMCID: PMC9026953 DOI: 10.1016/j.sjbs.2022.103301] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 03/12/2022] [Accepted: 04/17/2022] [Indexed: 12/14/2022] Open
Abstract
Lectins are defined as carbohydrate-binding proteins/glycoproteins of none immune origin, they are ubiquitous in nature, exist from bacteria to human cells. And due to their carbohydrate-binding recognition capacity, they have been a useful biological tool for the purification of glycoproteins and their subsequent characterization. Some plant lectins have also been revealed to own antinociceptive, antiulcer, and anti-inflammatory properties, where these features, in many instances, depending on the lectin carbohydrate-binding site. Coronavirus disease of 2019 (COVID-19) is a respiratory disease that struck the entire world leaving millions of people dead and more infected. Although COVID-19 vaccines have been made available, and quite a large number of world populations have already been immunized, the viral infection rates remained in acceleration, which continues to provoke major concern about the vaccines' efficacy. The belief in the ineffectiveness of the vaccine has been attributed in part to the recurrent mutations that occur in the epitope determinant fragments of the virus. Coronavirus envelope surface is extensively glycosylated being covered by more than sixty N-linked oligomannose, composite, and hybrid glycans with a core of Man3GlcNAc2Asn. In addition some O–linked glycans are also detected. Of these glyco-chains, many have also been exposed to several mutations, and a few remained conserved. Therefore, numerous plant lectins with a specificity directed towards these viral envelope sugars have been found to interact preferentially with them and are suggested to be scrutinized as a possible future tool to combat coronaviruses including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) through blocking the viral attachment to the host cells. In this review, we will discuss the possible applications of plant lectins as anti-coronaviruses including SARS-CoV-2, antinociceptive, anti-inflammatory, and antiulcer agents with the proposed mechanism of their actions.
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Affiliation(s)
- Emadeldin Konozy
- Department of Biotechnology, Africa City of Technology, Khartoum, Sudan
- Corresponding author.
| | - Makarim Osman
- Department of Zoology, University of Khartoum, Khartoum, Sudan
| | - Amina Dirar
- Medicinal, Aromatic Plants and Traditional Medicine Research Institute (MAPTRI), National Center for Research, Mek Nimr Street, Khartoum, Sudan
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6
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The Agglutinin of Common Nettle (Urtica dioica L.) Plant Effects on Gene Expression Related to Apoptosis of Human Acute Myeloid Leukemia Cell Line. Biochem Genet 2021; 59:1049-1064. [PMID: 33675488 DOI: 10.1007/s10528-020-10024-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Accepted: 12/12/2020] [Indexed: 10/22/2022]
Abstract
Treatment of acute myeloid leukemia (AML) requires new drugs as result of a rise in new cases and high disease relapse. Plant lectins with the ability to bind carbohydrates on the cell surface have the potential to treat cancer. Urtica dioica L. agglutinin (UDA) is a low weight lectin with anti-benign prostatic hyperplasia (BPH) impact. Here, we examine the impact of UDA on HL-60 cell line. Cytotoxicity and cytostatic effects were assessed in HL-60 cells treated with UDA and vincristine (positive control). The effects of the lectin on cell cycle phases and cell death mechanism were surveyed by propidium iodide (PI) staining and annexin V/PI, respectively. The activation status of the apoptosis pathway was determined by western blotting. Finally, the expression levels of 84 genes were examined by the Human cancer drug target gene PCR array kit. The results indicated that the increase in UDA concentration inhibited the proliferation of HL-60 cells as well as apoptosis induction. Cell cycle analysis showed that the number of sub G1 cells increased essentially. Experimental observations showed that UDA can induce cell apoptosis through a caspase 9-dependent pathway. The expression changes of 21 genes confirmed the apoptotic events in HL-60 cells treated with UDA. In this, we have presented the first investigation on the cytotoxic and apoptotic effects of a lectin isolated from rhizomes and roots of Urtica dioica L. on human AML cells. Generally, the results suggest that UDA may have therapeutic value for leukemia and would be studied further as a new drug for AML later on.
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7
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Mitchell CA, Ramessar K, O'Keefe BR. Antiviral lectins: Selective inhibitors of viral entry. Antiviral Res 2017; 142:37-54. [PMID: 28322922 PMCID: PMC5414728 DOI: 10.1016/j.antiviral.2017.03.007] [Citation(s) in RCA: 103] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 03/13/2017] [Indexed: 01/27/2023]
Abstract
Many natural lectins have been reported to have antiviral activity. As some of these have been put forward as potential development candidates for preventing or treating viral infections, we have set out in this review to survey the literature on antiviral lectins. The review groups lectins by structural class and class of source organism we also detail their carbohydrate specificity and their reported antiviral activities. The review concludes with a brief discussion of several of the pertinent hurdles that heterologous proteins must clear to be useful clinical candidates and cites examples where such studies have been reported for antiviral lectins. Though the clearest path currently being followed is the use of antiviral lectins as anti-HIV microbicides via topical mucosal administration, some investigators have also found systemic efficacy against acute infections following subcutaneous administration.
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Affiliation(s)
- Carter A Mitchell
- Molecular Targets Laboratory, Center for Cancer Research, National Cancer Institute, NIH, Frederick, MD, 21702-1201, USA
| | - Koreen Ramessar
- Molecular Targets Laboratory, Center for Cancer Research, National Cancer Institute, NIH, Frederick, MD, 21702-1201, USA
| | - Barry R O'Keefe
- Molecular Targets Laboratory, Center for Cancer Research, National Cancer Institute, NIH, Frederick, MD, 21702-1201, USA.
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8
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Grant OC, Tessier MB, Meche L, Mahal LK, Foley BL, Woods RJ. Combining 3D structure with glycan array data provides insight into the origin of glycan specificity. Glycobiology 2016; 26:772-783. [PMID: 26911287 PMCID: PMC4976521 DOI: 10.1093/glycob/cww020] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Revised: 02/17/2016] [Accepted: 02/17/2016] [Indexed: 12/30/2022] Open
Abstract
Defining how a glycan-binding protein (GBP) specifically selects its cognate glycan from among the ensemble of glycans within the cellular glycome is an area of intense study. Powerful insight into recognition mechanisms can be gained from 3D structures of GBPs complexed to glycans; however, such structures remain difficult to obtain experimentally. Here an automated 3D structure generation technique, called computational carbohydrate grafting, is combined with the wealth of specificity information available from glycan array screening. Integration of the array data with modeling and crystallography allows generation of putative co-complex structures that can be objectively assessed and iteratively altered until a high level of agreement with experiment is achieved. Given an accurate model of the co-complexes, grafting is also able to discern which binding determinants are active when multiple potential determinants are present within a glycan. In some cases, induced fit in the protein or glycan was necessary to explain the observed specificity, while in other examples a revised definition of the minimal binding determinants was required. When applied to a collection of 10 GBP-glycan complexes, for which crystallographic and array data have been reported, grafting provided a structural rationalization for the binding specificity of >90% of 1223 arrayed glycans. A webtool that enables researchers to perform computational carbohydrate grafting is available at www.glycam.org/gr (accessed 03 March 2016).
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Affiliation(s)
- Oliver C Grant
- Complex Carbohydrate Research Center and Department of Biochemistry, University of Georgia, 315 Riverbend Road, Athens, GA 30602, USA
| | - Matthew B Tessier
- Complex Carbohydrate Research Center and Department of Biochemistry, University of Georgia, 315 Riverbend Road, Athens, GA 30602, USA
| | - Lawrence Meche
- New York University Department of Chemistry, Biomedical Chemistry Institute, 100 Washington Square East, Room 1001, New York, NY 10003, USA
| | - Lara K Mahal
- New York University Department of Chemistry, Biomedical Chemistry Institute, 100 Washington Square East, Room 1001, New York, NY 10003, USA
| | - Bethany L Foley
- New York University Department of Chemistry, Biomedical Chemistry Institute, 100 Washington Square East, Room 1001, New York, NY 10003, USA
| | - Robert J Woods
- Complex Carbohydrate Research Center and Department of Biochemistry, University of Georgia, 315 Riverbend Road, Athens, GA 30602, USA
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9
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Patra D, Mishra P, Vijayan M, Surolia A. Negative Cooperativity and High Affinity in Chitooligosaccharide Binding by a Mycobacterium smegmatis Protein Containing LysM and Lectin Domains. Biochemistry 2015; 55:49-61. [DOI: 10.1021/acs.biochem.5b00841] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Dhabaleswar Patra
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012, India
| | - Padmanabh Mishra
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012, India
| | - Mamannamana Vijayan
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012, India
| | - Avadhesha Surolia
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012, India
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10
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Wang WJ, Cheng W, Luo M, Yan Q, Yu HM, Li Q, Cao DD, Huang S, Xu A, Mariuzza RA, Chen Y, Zhou CZ. Activity Augmentation of Amphioxus Peptidoglycan Recognition Protein BbtPGRP3 via Fusion with a Chitin Binding Domain. PLoS One 2015; 10:e0140953. [PMID: 26479246 PMCID: PMC4610682 DOI: 10.1371/journal.pone.0140953] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2015] [Accepted: 10/02/2015] [Indexed: 11/19/2022] Open
Abstract
Peptidoglycan recognition proteins (PGRPs), which have been identified in most animals, are pattern recognition molecules that involve antimicrobial defense. Resulting from extraordinary expansion of innate immune genes, the amphioxus encodes many PGRPs of diverse functions. For instance, three isoforms of PGRP encoded by Branchiostoma belcheri tsingtauense, termed BbtPGRP1~3, are fused with a chitin binding domain (CBD) at the N-terminus. Here we report the 2.7 Å crystal structure of BbtPGRP3, revealing an overall structure of an N-terminal hevein-like CBD followed by a catalytic PGRP domain. Activity assays combined with site-directed mutagenesis indicated that the individual PGRP domain exhibits amidase activity towards both DAP-type and Lys-type peptidoglycans (PGNs), the former of which is favored. The N-terminal CBD not only has the chitin-binding activity, but also enables BbtPGRP3 to gain a five-fold increase of amidase activity towards the Lys-type PGNs, leading to a significantly broadened substrate spectrum. Together, we propose that modular evolution via domain shuffling combined with gene horizontal transfer makes BbtPGRP1~3 novel PGRPs of augmented catalytic activity and broad recognition spectrum.
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Affiliation(s)
- Wen-Jie Wang
- Hefei National Laboratory for Physical Sciences at Microscale and the Innovation Center for Cell Signaling Network, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, China
| | - Wang Cheng
- Hefei National Laboratory for Physical Sciences at Microscale and the Innovation Center for Cell Signaling Network, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, China
| | - Ming Luo
- Hefei National Laboratory for Physical Sciences at Microscale and the Innovation Center for Cell Signaling Network, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, China
| | - Qingyu Yan
- State Key Laboratory of Biocontrol, Guangdong Key Laboratory of Pharmaceutical Functional Genes, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Hong-Mei Yu
- Hefei National Laboratory for Physical Sciences at Microscale and the Innovation Center for Cell Signaling Network, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, China
| | - Qiong Li
- Hefei National Laboratory for Physical Sciences at Microscale and the Innovation Center for Cell Signaling Network, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, China
| | - Dong-Dong Cao
- Hefei National Laboratory for Physical Sciences at Microscale and the Innovation Center for Cell Signaling Network, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, China
| | - Shengfeng Huang
- State Key Laboratory of Biocontrol, Guangdong Key Laboratory of Pharmaceutical Functional Genes, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Anlong Xu
- State Key Laboratory of Biocontrol, Guangdong Key Laboratory of Pharmaceutical Functional Genes, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Roy A. Mariuzza
- University of Maryland Institute for Bioscience and Biotechnology Research, W. M. Keck Laboratory for Structural Biology, Rockville, Maryland, United States of America
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland, United States of America
| | - Yuxing Chen
- Hefei National Laboratory for Physical Sciences at Microscale and the Innovation Center for Cell Signaling Network, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, China
- * E-mail: (YC); (CZZ)
| | - Cong-Zhao Zhou
- Hefei National Laboratory for Physical Sciences at Microscale and the Innovation Center for Cell Signaling Network, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, China
- * E-mail: (YC); (CZZ)
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11
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Castillo-Acosta VM, Ruiz-Pérez LM, Van Damme EJM, Balzarini J, González-Pacanowska D. Exposure of Trypanosoma brucei to an N-acetylglucosamine-binding lectin induces VSG switching and glycosylation defects resulting in reduced infectivity. PLoS Negl Trop Dis 2015; 9:e0003612. [PMID: 25746926 PMCID: PMC4351956 DOI: 10.1371/journal.pntd.0003612] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Accepted: 02/10/2015] [Indexed: 12/22/2022] Open
Abstract
Trypanosoma brucei variant surface glycoproteins (VSG) are glycosylated by both paucimannose and oligomannose structures which are involved in the formation of a protective barrier against the immune system. Here, we report that the stinging nettle lectin (UDA), with predominant N-acetylglucosamine-binding specificity, interacts with glycosylated VSGs and kills parasites by provoking defects in endocytosis together with impaired cytokinesis. Prolonged exposure to UDA induced parasite resistance based on a diminished capacity to bind the lectin due to an enrichment of biantennary paucimannose and a reduction of triantennary oligomannose structures. Two molecular mechanisms involved in resistance were identified: VSG switching and modifications in N-glycan composition. Glycosylation defects were correlated with the down-regulation of the TbSTT3A and/or TbSTT3B genes (coding for oligosaccharyltransferases A and B, respectively) responsible for glycan specificity. Furthermore, UDA-resistant trypanosomes exhibited severely impaired infectivity indicating that the resistant phenotype entails a substantial fitness cost. The results obtained further support the modification of surface glycan composition resulting from down-regulation of the genes coding for oligosaccharyltransferases as a general resistance mechanism in response to prolonged exposure to carbohydrate-binding agents.
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Affiliation(s)
- Víctor M. Castillo-Acosta
- Instituto de Parasitología y Biomedicina “López-Neyra”, Consejo Superior de Investigaciones Científicas, Parque Tecnológico de Ciencias de la Salud, Granada, Spain
| | - Luis M. Ruiz-Pérez
- Instituto de Parasitología y Biomedicina “López-Neyra”, Consejo Superior de Investigaciones Científicas, Parque Tecnológico de Ciencias de la Salud, Granada, Spain
| | - Els J. M. Van Damme
- Laboratory of Biochemistry and Glycobiology, Department of Molecular Biotechnology, Ghent University, Ghent, Belgium
| | - Jan Balzarini
- Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | - Dolores González-Pacanowska
- Instituto de Parasitología y Biomedicina “López-Neyra”, Consejo Superior de Investigaciones Científicas, Parque Tecnológico de Ciencias de la Salud, Granada, Spain
- * E-mail:
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12
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Wheat germ in vitro translation to produce one of the most toxic sodium channel specific toxins. Biosci Rep 2014; 34:BSR20140050. [PMID: 24924257 PMCID: PMC4114062 DOI: 10.1042/bsr20140050] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Envenoming following scorpion sting is a common emergency in many parts of the world. During scorpion envenoming, highly toxic small polypeptides of the venom diffuse rapidly within the victim causing serious medical problems. The exploration of toxin structure-function relationship would benefit from the generation of soluble recombinant scorpion toxins in Escherichia coli. We developed an in vitro wheat germ translation system for the expression of the highly toxic Aah (Androctonus australis hector)II protein that requires the proper formation of four disulphide bonds. Soluble, recombinant N-terminal GST (glutathione S-transferase)-tagged AahII toxin is obtained in this in vitro translation system. After proteolytic removal of the GST-tag, purified rAahII (recombinant AahII) toxin, which contains two extra amino acids at its N terminal relative to the native AahII, is highly toxic after i.c.v. (intracerebroventricular) injection in Swiss mice. An LD50 (median lethal dose)-value of 10 ng (or 1.33 pmol), close to that of the native toxin (LD50 of 3 ng) indicates that the wheat germ in vitro translation system produces properly folded and biological active rAahII. In addition, NbAahII10 (Androctonus australis hector nanobody 10), a camel single domain antibody fragment, raised against the native AahII toxin, recognizes its cognate conformational epitope on the recombinant toxin and neutralizes the toxicity of purified rAahII upon injection in mice. A wheat germ embryo derived cell-free translation system expresses a biologically active, highly toxic scorpion venom protein that is fully neutralized by a camel single domain antibody fragment raised against the native scorpion toxin.
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13
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Bobbili KB, Bandari S, Grobe K, Swamy MJ. Mutational analysis of the pumpkin (Cucurbita maxima) phloem exudate lectin, PP2 reveals Ser-104 is crucial for carbohydrate binding. Biochem Biophys Res Commun 2014; 450:622-7. [DOI: 10.1016/j.bbrc.2014.06.024] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Accepted: 06/05/2014] [Indexed: 11/29/2022]
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14
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Application, chemical composition, and standardization of nettle raw material and related drugs (Review). Pharm Chem J 2012. [DOI: 10.1007/s11094-012-0690-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/08/2022]
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15
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Roldós V, Cañada FJ, Jiménez-Barbero J. Carbohydrate-Protein Interactions: A 3D View by NMR. Chembiochem 2011; 12:990-1005. [DOI: 10.1002/cbic.201000705] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2010] [Indexed: 12/29/2022]
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16
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Uslu S, Bulbul A, Diler B, Bas EK, Nuhoglu A. Urticaria due to Urtica dioica in a neonate. Eur J Pediatr 2011; 170:401-3. [PMID: 20953796 DOI: 10.1007/s00431-010-1327-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2010] [Accepted: 10/05/2010] [Indexed: 11/26/2022]
Abstract
Urticaria is one of the most common dermatoses during the childhood, but it is very rare in the neonates. A 17-day-old infant with a generalized urticaria was admitted to our pediatric emergency unit. The mother of the infant reported having applied water boiled with stinging nettle (Urtica dioica) onto her nipples twice a day (before and after each breastfeeding) for 2 days in order to heal her nipple cracks. Serum total immunoglobulin E (IgE) and specific IgE levels for stinging nettle were high in the infant and the mother. The rashes began to regress within the first day of the hospitalization and disappeared completely on the second day without treatment. The skin prick test with the water boiled with stinging nettle was positive for the infant with significant induration, but not for the mother. Conclusion Reporting the first urticaria case in newborns due to stinging nettle, the authors suggest that breastfeeding mothers should always consult a physician before using skincare products.
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Affiliation(s)
- Sinan Uslu
- Department of Pediatrics, Division of Neonatology, Sisli Etfal Children Hospital, Istanbul, Turkey.
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17
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Hernández-Gay JJ, Ardá A, Eller S, Mezzato S, Leeflang BR, Unverzagt C, Cañada FJ, Jiménez-Barbero J. Insights into the Dynamics and Molecular Recognition Features of Glycopeptides by Protein Receptors: The 3D Solution Structure of Hevein Bound to the Trisaccharide Core of N-Glycoproteins. Chemistry 2010; 16:10715-26. [DOI: 10.1002/chem.201000939] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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18
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Kezuka Y, Kojima M, Mizuno R, Suzuki K, Watanabe T, Nonaka T. Structure of full-length class I chitinase from rice revealed by X-ray crystallography and small-angle X-ray scattering. Proteins 2010; 78:2295-305. [DOI: 10.1002/prot.22742] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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19
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Abstract
This overview provides an illustrated, comprehensive survey of some commonly observed protein‐fold families and structural motifs, chosen for their functional significance. It opens with descriptions and definitions of the various elements of protein structure and associated terminology. Following is an introduction into web‐based structural bioinformatics that includes surveys of interactive web servers for protein fold or domain annotation, protein‐structure databases, protein‐structure‐classification databases, structural alignments of proteins, and molecular graphics programs available for personal computers. The rest of the overview describes selected families of protein folds in terms of their secondary, tertiary, and quaternary structural arrangements, including ribbon‐diagram examples, tables of representative structures with references, and brief explanations pointing out their respective biological and functional significance.
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Affiliation(s)
- Peter D Sun
- National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, USA
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20
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Chávez MI, Andreu C, Vidal P, Aboitiz N, Freire F, Groves P, Asensio JL, Asensio G, Muraki M, Cañada FJ, Jiménez-Barbero J. On the importance of carbohydrate-aromatic interactions for the molecular recognition of oligosaccharides by proteins: NMR studies of the structure and binding affinity of AcAMP2-like peptides with non-natural naphthyl and fluoroaromatic residues. Chemistry 2006; 11:7060-74. [PMID: 16220560 DOI: 10.1002/chem.200500367] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The specific interaction of a variety of modified hevein domains to chitooligosaccharides has been studied by NMR spectroscopy in order to assess the importance of aromatic-carbohydrate interactions for the molecular recognition of neutral sugars. These mutant AcAMP2-like peptides, which have 4-fluoro-phenylalanine, tryptophan, or 2-naphthylalanine at the key interacting positions, have been prepared by solid-phase synthesis. Their three-dimensional structures, when bound to the chitin-derived trisaccharide, have been deduced by NMR spectroscopy. By using DYANA and restrained molecular dynamics simulations with the AMBER 5.0 force field, the three-dimensional structures of the protein-sugar complexes have been obtained. The thermodynamic analysis of the interactions that occur upon complex formation have also been carried out. Regarding binding affinity, the obtained data have permitted the deduction that the larger the aromatic group, the higher the association constant and the binding enthalpy. In all cases, entropy opposes binding. In contrast, deactivation of the aromatic rings by attaching fluorine atoms decreases the binding affinity, with a concomitant decrease in enthalpy. The role of the chemical nature of the aromatic ring for establishing sugar contacts has been thus evaluated.
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Affiliation(s)
- M Isabel Chávez
- Department of Protein Structure and Function, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
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21
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Large-molecular-weight carbohydrate-binding agents as HIV entry inhibitors targeting glycoprotein gp120. Curr Opin HIV AIDS 2006; 1:355-60. [DOI: 10.1097/01.coh.0000239846.36076.2c] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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22
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Balzarini J. Inhibition of HIV entry by carbohydrate-binding proteins. Antiviral Res 2006; 71:237-47. [PMID: 16569440 DOI: 10.1016/j.antiviral.2006.02.004] [Citation(s) in RCA: 113] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2006] [Revised: 01/31/2006] [Accepted: 02/01/2006] [Indexed: 11/18/2022]
Abstract
Carbohydrate-binding proteins (CBP) can be isolated from a variety of species, including procaryotes (i.e. cyanobacteria), sea corals, algae, plants, invertebrates and vertebrates. A number of them, in particular those CBP that show specific recognition for mannose (Man) and N-acetylglucosamine (GlcNAc) are endowed with a remarkable anti-HIV activity in cell culture. The smallest CBP occur as monomeric peptides with a molecular weight of approximately 8.5 kDa. Many others are functionally dimers, trimers or tetramers, and their molecular weight can sometimes largely exceed 50 kDa. CBP can contain 2 to up to 12 carbohydrate-binding sites per single molecule, depending on the nature of the lectin and its oligomerization state. CBP qualify as potential anti-HIV microbicide drugs because they not only inhibit infection of cells by cell-free virus (in some cases in the lower nano- or even subnanomolar range) but they can also efficiently prevent virus transmission from virus-infected cells to uninfected T-lymphocytes. Their most likely mechanism of antiviral action is the interruption of virus entry (i.e. fusion) into its target cell. CBP presumably act by direct binding to the glycans that are abundantly present on the HIV-1 gp120 envelope. They may cross-link several glycans during virus/cell interaction and/or freeze the conformation of gp120 consequently preventing further interaction with the coreceptor. Several CBP were shown to have a high genetic barrier since multiple (>or=5) glycan deletions in the HIV envelope are necessary to provoke a moderate level of drug resistance. CBP are the prototypes of conceptionally novel chemotherapeutics with a unique mechanism of antiviral action, drug resistance profile and an intrinsic capacity to trigger a specific immune response against HIV strains after glycan deletions on their envelope occur in an attempt to escape CBP drug pressure.
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Affiliation(s)
- J Balzarini
- Rega Institute for Medical Research, K.U. Leuven, Minderbroedersstraat 10, B-3000 Leuven, Belgium.
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23
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Jiménez-Barbero J, Javier Cañada F, Asensio JL, Aboitiz N, Vidal P, Canales A, Groves P, Gabius HJ, Siebert HC. Hevein Domains: An Attractive Model to Study Carbohydrate–Protein Interactions at Atomic Resolution. Adv Carbohydr Chem Biochem 2006; 60:303-54. [PMID: 16750446 DOI: 10.1016/s0065-2318(06)60007-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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24
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Balzarini J, Van Laethem K, Hatse S, Froeyen M, Peumans W, Van Damme E, Schols D. Carbohydrate-binding Agents Cause Deletions of Highly Conserved Glycosylation Sites in HIV GP120. J Biol Chem 2005; 280:41005-14. [PMID: 16183648 DOI: 10.1074/jbc.m508801200] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mannose-binding proteins derived from several plants (i.e. Hippeastrum hybrid and Galanthus nivalis agglutinin) or prokaryotes (i.e. cyanovirin-N) inhibit human immunodeficiency virus (HIV) replication and select for drug-resistant viruses that show profound deletion of N-glycosylation sites in the GP120 envelope (Balzarini, J., Van Laethem, K., Hatse, S., Vermeire, K., De Clercq, E., Peumans, W., Van Damme, E., Vandamme, A.-M., Bolmstedt, A., and Schols, D. (2004) J. Virol. 78, 10617-10627; Balzarini, J., Van Laethem, K., Hatse, S., Froeyen, M., Van Damme, E., Bolmstedt, A., Peumans, W., De Clercq, E., and Schols, D. (2005) Mol. Pharmacol. 67, 1556-1565). Here we demonstrated that the N-acetylglucosamine-binding protein from Urtica dioica (UDA) prevents HIV entry and eventually selects for viruses in which conserved N-glycosylation sites in GP120 were deleted. In contrast to the mannose-binding proteins, which have a 50-100-fold decreased antiviral activity against the UDA-exposed mutant viruses, UDA has decreased anti-HIV activity to a very limited extent, even against those mutant virus strains that lack at least 9 of 22 ( approximately 40%) glycosylation sites in their GP120 envelope. Therefore, UDA represents the prototype of a new conceptual class of carbohydrate-binding agents with an unusually specific and targeted drug resistance profile. It forces HIV to escape drug pressure by deleting the indispensable glycans on its GP120, thereby obligatorily exposing previously hidden immunogenic epitopes on its envelope.
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Affiliation(s)
- Jan Balzarini
- Rega Institute for Medical Research, Katholieke Universiteit Leuven, Belgium.
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25
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Botos I, Wlodawer A. Proteins that bind high-mannose sugars of the HIV envelope. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2005; 88:233-82. [PMID: 15572157 DOI: 10.1016/j.pbiomolbio.2004.05.001] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
A broad range of proteins bind high-mannose carbohydrates found on the surface of the envelope protein gp120 of the human immunodeficiency virus and thus interfere with the viral life cycle, providing a potential new way of controlling HIV infection. These proteins interact with the carbohydrate moieties in different ways. A group of them interacts as typical C-type lectins via a Ca2+ ion. Another group interacts with specific single, terminal sugars, without the help of a metal cation. A third group is involved in more intimate interactions, with multiple carbohydrate rings and no metal ion. Finally, there is a group of lectins for which the interaction mode has not yet been elucidated. This review summarizes, principally from a structural point of view, the current state of knowledge about these high-mannose binding proteins and their mode of sugar binding.
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Affiliation(s)
- Istvan Botos
- Macromolecular Crystallography Laboratory, National Cancer Institute, NCI-Frederick, Building 536, Room 5, Frederick, MD 21702-1201, USA
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26
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Aboitiz N, Vila-Perelló M, Groves P, Asensio JL, Andreu D, Cañada FJ, Jiménez-Barbero J. NMR and modeling studies of protein-carbohydrate interactions: synthesis, three-dimensional structure, and recognition properties of a minimum hevein domain with binding affinity for chitooligosaccharides. Chembiochem 2005; 5:1245-55. [PMID: 15368576 DOI: 10.1002/cbic.200400025] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
HEV32, a 32-residue, truncated hevein lacking eleven C-terminal amino acids, was synthesized by solid-phase methodology and correctly folded with three cysteine bridge pairs. The affinities of HEV32 for small chitin fragments--in the forms of N,N',N"-triacetylchitotriose ((GlcNAc)3) (millimolar) and N,N',N",N"',N"",N""'-hexaacetylchitohexaose ((GlcNAc)6) (micromolar)--as measured by NMR and fluorescence methods, are comparable with those of native hevein. The HEV32 ligand-binding process is enthalpy driven, while entropy opposes binding. The NMR structure of ligand-bound HEV32 in aqueous solution was determined to be highly similar to the NMR structure of ligand-bound hevein. Solvated molecular-dynamics simulations were performed in order to monitor the changes in side-chain conformation of the binding site of HEV32 and hevein upon interaction with ligands. The calculations suggest that the Trp21 side-chain orientation of HEV32 in the free form differs from that in the bound state; this agrees with fluorescence and thermodynamic data. HEV32 provides a simple molecular model for studying protein-carbohydrate interactions and for understanding the physiological relevance of small native hevein domains lacking C-terminal residues.
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Affiliation(s)
- Nuria Aboitiz
- Department of Protein Structure and Function, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, 28040 Madrid, Spain
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Boraston A, Bolam D, Gilbert H, Davies G. Carbohydrate-binding modules: fine-tuning polysaccharide recognition. Biochem J 2005; 382:769-81. [PMID: 15214846 PMCID: PMC1133952 DOI: 10.1042/bj20040892] [Citation(s) in RCA: 1419] [Impact Index Per Article: 74.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2004] [Revised: 06/15/2004] [Accepted: 06/23/2004] [Indexed: 11/17/2022]
Abstract
The enzymic degradation of insoluble polysaccharides is one of the most important reactions on earth. Despite this, glycoside hydrolases attack such polysaccharides relatively inefficiently as their target glycosidic bonds are often inaccessible to the active site of the appropriate enzymes. In order to overcome these problems, many of the glycoside hydrolases that utilize insoluble substrates are modular, comprising catalytic modules appended to one or more non-catalytic CBMs (carbohydrate-binding modules). CBMs promote the association of the enzyme with the substrate. In view of the central role that CBMs play in the enzymic hydrolysis of plant structural and storage polysaccharides, the ligand specificity displayed by these protein modules and the mechanism by which they recognize their target carbohydrates have received considerable attention since their discovery almost 20 years ago. In the last few years, CBM research has harnessed structural, functional and bioinformatic approaches to elucidate the molecular determinants that drive CBM-carbohydrate recognition. The present review summarizes the impact structural biology has had on our understanding of the mechanisms by which CBMs bind to their target ligands.
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Affiliation(s)
- Alisdair B. Boraston
- *Biochemistry and Microbiology, University of Victoria, PO Box 3055 STN CSC, Victoria, BC, Canada V8W 3P6
- To whom correspondence should be addressed (email )
| | - David N. Bolam
- †School of Cell and Molecular Biosciences, University of Newcastle upon Tyne, Newcastle upon Tyne NE1 7RU, U.K
| | - Harry J. Gilbert
- †School of Cell and Molecular Biosciences, University of Newcastle upon Tyne, Newcastle upon Tyne NE1 7RU, U.K
| | - Gideon J. Davies
- ‡Structural Biology Laboratory, Department of Chemistry, The University of York, Heslington, York YO10 5YW, U.K
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Carrizo ME, Capaldi S, Perduca M, Irazoqui FJ, Nores GA, Monaco HL. The Antineoplastic Lectin of the Common Edible Mushroom (Agaricus bisporus) Has Two Binding Sites, Each Specific for a Different Configuration at a Single Epimeric Hydroxyl. J Biol Chem 2005; 280:10614-23. [PMID: 15596442 DOI: 10.1074/jbc.m411989200] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The lectin from the common mushroom Agaricus bisporus, the most popular edible species in Western countries, has potent antiproliferative effects on human epithelial cancer cells, without any apparent cytotoxicity. This property confers to it an important therapeutic potential as an antineoplastic agent. The three-dimensional structure of the lectin was determined by x-ray diffraction. The protein is a tetramer with 222 symmetry, and each monomer presents a novel fold with two beta sheets connected by a helix-loop-helix motif. Selectivity was studied by examining the binding of four monosaccharides and seven disaccharides in two different crystal forms. The T-antigen disaccharide, Galbeta1-3GalNAc, mediator of the antiproliferative effects of the protein, binds at a shallow depression on the surface of the molecule. The binding of N-acetylgalactosamine overlaps with that moiety of the T antigen, but surprisingly, N-acetylglucosamine, which differs from N-acetylgalactosamine only in the configuration of epimeric hydroxyl 4, binds at a totally different site on the opposite side of the helix-loop-helix motif. The lectin thus has two distinct binding sites per monomer that recognize the different configuration of a single epimeric hydroxyl. The structure of the protein and its two carbohydrate-binding sites are described in detail in this study.
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Affiliation(s)
- Maria E Carrizo
- Biocrystallography Laboratory, Department of Science and Technology, University of Verona, Strada Le Grazie 15, 37134 Verona, Italy
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29
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Xiang Y, Huang RH, Liu XZ, Zhang Y, Wang DC. Crystal structure of a novel antifungal protein distinct with five disulfide bridges from Eucommia ulmoides Oliver at an atomic resolution. J Struct Biol 2005; 148:86-97. [PMID: 15363789 DOI: 10.1016/j.jsb.2004.04.002] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2003] [Revised: 03/16/2004] [Indexed: 11/22/2022]
Abstract
EAFP2 is a novel antifungal protein isolated from the bark of the tree Eucommia ulmoides Oliver. It consists of 41 residues and is characterized with a five-disulfide motif and the inhibitory effects on the growth of both cell wall chitin-containing and chitin-free fungi. The crystal structure of EAFP2 at an atomic resolution of 0.84 A has been determined by using Shake-and-Bake direct methods with the program SnB. The phases obtained were of sufficient quality to permit the initial model built automatically and the structural refinement carried out using anisotropic displacement parameters resulted in a final crystallographic R factor of 6.8%. In the resulting structural model, all non-hydrogen protein atoms including an unusual pyroglutamyl acid residue at the N-terminal can fit to the articulated electron densities with one centre and more than 65% of the hydrogen atoms in the protein can be observed as individual peaks in the difference map. The general fold of EAFP2 is composed of a 3(10) helix (Cys3-Arg6), an alpha-helix (Ala27-Cys31) and a three-stranded antiparallel beta-sheet (Cys16-Ser18, Cys23-Ser25, and Cys35-Cys37) and cross-linked by five disulfide bridges. The tertiary structure of EAFP2 can be divided into two structural sectors, A and B. Sector A composed of residues 11-30 adopts a conformation similar to the chitin-binding domain in the hevein-like proteins and features a hydrophobic surface embraced a chitin-binding site (Tyr20, 22, 29, and Ser18). The distinct disulfide bridge Cys7-Cys37 connects the N-terminal ten residues with the C-terminal segment 35-41 to form the sector B, which features a cationic surface distributing all four positively charged residues, Arg6, 9, 36, and 40. Based on these structural features, the possible structural basis of the functional properties of EAFP2 is discussed.
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Affiliation(s)
- Ye Xiang
- Center for Structural and Molecular Biology, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, People's Republic of China
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30
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Zhao Y, Li Z, Drozd SJ, Guo Y, Mourad W, Li H. Crystal structure of Mycoplasma arthritidis mitogen complexed with HLA-DR1 reveals a novel superantigen fold and a dimerized superantigen-MHC complex. Structure 2004; 12:277-88. [PMID: 14962388 PMCID: PMC3923524 DOI: 10.1016/j.str.2004.01.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2003] [Revised: 10/15/2003] [Accepted: 10/16/2003] [Indexed: 01/24/2023]
Abstract
Mycoplasma arthritidis-derived mitogen (MAM) is a superantigen that can activate large fractions of T cells bearing particular TCR Vbeta elements. Here we report the crystal structure of MAM complexed with a major histocompatibility complex (MHC) antigen, HLA-DR1, loaded with haemagglutinin peptide 306-318 (HA). The structure reveals that MAM has a novel fold composed of two alpha-helical domains. This fold is entirely different from that of the pyrogenic superantigens, consisting of a beta-grasped motif and a beta barrel. In the complex, the N-terminal domain of MAM binds orthogonally to the MHC alpha1 domain and the bound HA peptide, and to a lesser extent to the MHC beta1 domain. Two MAM molecules form an asymmetric dimer and cross-link two MHC antigens to form a plausible, dimerized MAM-MHC complex. These data provide the first crystallographic evidence that superantigens can dimerize MHC molecules. Based on our structure, a model of the TCR2MAM2MHC2 complex is proposed.
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Affiliation(s)
- Yiwei Zhao
- Wadsworth Center, New York State Department of Health, State University of New York at Albany, Empire State Plaza, P.O. Box 509, Albany, New York 12201
| | - Zhong Li
- Wadsworth Center, New York State Department of Health, State University of New York at Albany, Empire State Plaza, P.O. Box 509, Albany, New York 12201
| | - Sandra J. Drozd
- Wadsworth Center, New York State Department of Health, State University of New York at Albany, Empire State Plaza, P.O. Box 509, Albany, New York 12201
| | - Yi Guo
- Wadsworth Center, New York State Department of Health, State University of New York at Albany, Empire State Plaza, P.O. Box 509, Albany, New York 12201
| | - Walid Mourad
- Centre de Recherche en Immunologie, et Rhumatologie, CHUQ, Pavillon CHUL, Université Laval, Québec, Québec G1V-4G2, Canada
| | - Hongmin Li
- Wadsworth Center, New York State Department of Health, State University of New York at Albany, Empire State Plaza, P.O. Box 509, Albany, New York 12201
- Department of Biomedical Sciences, School of Public Health, State University of New York at Albany, Empire State Plaza, P.O. Box 509, Albany, New York 12201
- Correspondence:
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Saito A, Schrempf H. Mutational analysis of the binding affinity and transport activity for N -acetylglucosamine of the novel ABC transporter Ngc in the chitin-degrader Streptomyces olivaceoviridis. Mol Genet Genomics 2004; 271:545-53. [PMID: 15148605 DOI: 10.1007/s00438-004-0981-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2003] [Accepted: 01/08/2004] [Indexed: 10/26/2022]
Abstract
The highly differentiated bacterium Streptomyces olivaceoviridis efficiently hydrolyses chitin, a highly abundant natural polysaccharide, to low molecular weight products including N-acetylglucosamine (NAG) and N,N' -diacetylchitobiose (chitobiose). NAG is taken up by a PTS (phosphoenolpyruvate-dependent phosphotransferase system) which includes the PtsC2 protein, and via the ABC (ATP-binding cassette) transporter Ngc, which itself includes the substrate-binding protein NgcE. This is at present the only ABC transporter which is known to mediate specific uptake of NAG (K(m) 0.48 microM, V(max) 1.3 nmol/min/mg dry weight) and is competitively inhibited by chitobiose (K(i) 0.68 microM). The latter finding suggests that the Ngc system transports both NAG and chitobiose efficiently. To identify amino acid residues required for the function of NgcE, either the wild-type or one of several mutant forms of the ngcE gene was introduced into the strain S. olivaceoviridis DeltaNgcE/DeltaPtsC1/DeltaPtsC2, which lacks both functional transport systems for NAG, and chromosomal recombinants were selected. Based on the in vivo transport parameters of the recombinants, and the in vitro binding characteristics of the corresponding purified proteins, the following conclusions can be drawn. (1) Replacement of the C-terminally located residue Y396 by A (Y396A) has little effect on ligand-binding or transport parameters. The W395A mutation also induced little change in the substrate affinity in vitro, but it led in vivo to a marked increase (11 fold) in K(m), and enhanced V(max) (by 1.5 fold). (2) The amino acids Y201 and W280 both contribute (51% and 38%) to the ligand-binding capacity of NgcE. They are both very important for the in vivo function of the complete transport apparatus; strains expressing either Y201A or W280A show drastically (100 or 150 times) enhanced K(m) values. (3) The concomitant presence of either Y200 and W280 or Y201 and W280 is essential for the function of NgcE. (4) Y201 is located within a tyrosyl-rich motif. This has been found to share some features with the ligand-binding site of amelogenins (enamel matrix proteins), which interact with NAG residues in glycoconjugates. In addition, it is distantly related to the ligand-binding site(s) in the plant-lectins UDA ( Urtica dioicaagglutinin, specific for NAG and its oligomers) and WGA (wheat germ agglutinin, which recognises a motif comprising three consecutive NAG residues).
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Affiliation(s)
- A Saito
- Fachbereich Biologie/Chemie, Universität Osnabrück, Barbarastr. 11, 49069, Osnabrück, Germany
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van den Burg HA, Spronk CAEM, Boeren S, Kennedy MA, Vissers JPC, Vuister GW, de Wit PJGM, Vervoort J. Binding of the AVR4 elicitor of Cladosporium fulvum to chitotriose units is facilitated by positive allosteric protein-protein interactions: the chitin-binding site of AVR4 represents a novel binding site on the folding scaffold shared between the invertebrate and the plant chitin-binding domain. J Biol Chem 2004; 279:16786-96. [PMID: 14769793 DOI: 10.1074/jbc.m312594200] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The attack of fungal cell walls by plant chitinases is an important plant defense response to fungal infection. Anti-fungal activity of plant chitinases is largely restricted to chitinases that contain a noncatalytic, plant-specific chitin-binding domain (ChBD) (also called Hevein domain). Current data confirm that the race-specific elicitor AVR4 of the tomato pathogen Cladosporium fulvum can protect fungi against plant chitinases, which is based on the presence of a novel type of ChBD in AVR4 that was first identified in invertebrates. Although these two classes of ChBDs (Hevein and invertebrate) are sequentially unrelated, they share structural homology. Here, we show that the chitin-binding sites of these two classes of ChBDs have different topologies and characteristics. The K(D), DeltaH, and DeltaS values obtained for the interaction between AVR4 and chito-oligomers are comparable with those obtained for Hevein. However, the binding site of AVR4 is larger than that of Hevein, i.e. AVR4 interacts strictly with chitotriose, whereas Hevein can also interact with the monomer N-acetylglucosamine. Moreover, binding of additional AVR4 molecules to chitin occurs through positive cooperative protein-protein interactions. By this mechanism AVR4 is likely to effectively shield chitin on the fungal cell wall, preventing the cell wall from being degraded by plant chitinases.
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Affiliation(s)
- Harrold A van den Burg
- Laboratorie of Biochemistry, Wageningen University, NL-6703 HA Wageningen, The Netherlands
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Peumans WJ, Rougé P, Van Damme EJM. The tomato lectin consists of two homologous chitin-binding modules separated by an extensin-like linker. Biochem J 2004; 376:717-24. [PMID: 14503921 PMCID: PMC1223818 DOI: 10.1042/bj20031069] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2003] [Accepted: 09/22/2003] [Indexed: 11/17/2022]
Abstract
A cDNA encoding a putative lectin expressed in tomato leaves was identified and analysed. The lectin consists of two homologous chitin-binding modules interconnected by a short proline-rich domain containing a single Ser[Pro]( n ) repetitive motif. Each module comprises two in-tandem-arrayed hevein domains separated by a tetrapeptide linker. Besides the chitin-binding modules and proline-rich domain, the lectin contains two short unrelated domains located at the N- and C-termini of the protein respectively. Eventual elucidation of the molecular structure of the tomato lectin confirms the presumed chimaeric nature of the Solanaceae lectins but also indicates that all previously proposed models need to be revised.
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Affiliation(s)
- Willy J Peumans
- Department of Molecular Biotechnology, Ghent University, Coupure Links 653, 9000 Gent, Belgium
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Van Damme EJM, Barre A, Rougé P, Peumans WJ. Potato lectin: an updated model of a unique chimeric plant protein. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2004; 37:34-45. [PMID: 14675430 DOI: 10.1046/j.1365-313x.2003.01929.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A complete cDNA encoding a potato tuber lectin has been identified and sequenced. Based on the deduced amino acid sequence, the still enigmatic molecular structure of the classical chimeric potato lectin could eventually be determined. Basically, the potato lectin consists of two nearly identical chitin-binding modules, built up of two in-tandem arrayed hevein domains that are interconnected by an extensin-like domain of approximately 60 amino acid residues. Although this structure confirms the 'canonical' chimeric nature of the Solanaceae lectins, it differs fundamentally from all previously proposed models. The new insights in the structure are also discussed in view of the physiological role of the Solanaceae lectins.
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Affiliation(s)
- Els J M Van Damme
- Department of Molecular Biotechnology, Ghent University, Coupure Links 653, 9000 Gent, Belgium. ElsJM.Van
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Hayashida M, Fujii T, Hamasu M, Ishiguro M, Hata Y. Similarity between Protein–Protein and Protein–Carbohydrate Interactions, Revealed by Two Crystal Structures of Lectins from the Roots of Pokeweed. J Mol Biol 2003; 334:551-65. [PMID: 14623194 DOI: 10.1016/j.jmb.2003.09.076] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The roots of pokeweed (Phytolacca americana) are known to contain the lectins designated PL-A, PL-B, PL-C, PL-D1, and PL-D2. Of these lectins, the crystal structures of two PLs, the ligand-free PL-C and the complex of PL-D2 with tri-N-acetylchitotriose, have been determined at 1.8A resolution. The polypeptide chains of PL-C and PL-D2 form three and two repetitive chitin-binding domains, respectively. In the crystal structure of the PL-D2 complex, one trisaccharide molecule is shared mainly between two neighboring molecules related to each other by a crystallographic 2(1)-screw axis, and infinite helical chains of complexed molecules are generated by the sharing of ligand molecules. The crystal structure of PL-C reveals that the molecule is a dimer of two identical subunits, whose polypeptide chains are located in a head-to-tail fashion by a molecular 2-fold axis. Three putative carbohydrate-binding sites in each subunit are located in the dimer interface. The dimerization of PL-C is performed through the hydrophobic interactions between the carbohydrate-binding sites of the opposite domains in the dimer, leading to a distinct dimerization mode from that of wheat-germ agglutinin. Three aromatic residues in each carbohydrate-binding site of PL-C are involved in the dimerization. These residues correspond to the residues that interact mainly with the trisaccharide in the PL-D2 complex and appear to mimic the saccharide residues in the complex. Consequently, the present structure of the PL-C dimer has no room for accommodating carbohydrate. The quaternary structure of PL-C formed through these putative carbohydrate-binding residues may lead to the lack of hemagglutinating activity.
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Affiliation(s)
- Minoru Hayashida
- Institute for Chemical Research, Kyoto University, Uji, 611-0011, Kyoto, Japan
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Hemmi H, Ishibashi J, Tomie T, Yamakawa M. Structural basis for new pattern of conserved amino acid residues related to chitin-binding in the antifungal peptide from the coconut rhinoceros beetle Oryctes rhinoceros. J Biol Chem 2003; 278:22820-7. [PMID: 12676931 DOI: 10.1074/jbc.m301025200] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Scarabaecin isolated from hemolymph of the coconut rhinoceros beetle Oryctes rhinoceros is a 36-residue polypeptide that has antifungal activity. The solution structure of scarabaecin has been determined from twodimensional 1H NMR spectroscopic data and hybrid distance geometry-simulated annealing protocol calculation. Based on 492 interproton and 10 hydrogen-bonding distance restraints and 36 dihedral angle restraints, we obtained 20 structures. The average backbone root-mean-square deviation for residues 4-35 is 0.728 +/- 0.217 A from the mean structure. The solution structure consists of a two-stranded antiparallel beta-sheet connected by a type-I beta-turn after a short helical turn. All secondary structures and a conserved disulfide bond are located in the C-terminal half of the peptide, residues 18-36. Overall folding is stabilized by a combination of a disulfide bond, seven hydrogen bonds, and numerous hydrophobic interactions. The structural motif of the C-terminal half shares a significant tertiary structural similarity with chitin-binding domains of plant and invertebrate chitin-binding proteins, even though scarabaecin has no overall sequence similarity to other peptide/polypeptides including chitin-binding proteins. The length of its primary structure, the number of disulfide bonds, and the pattern of conserved functional residues binding to chitin in scarabaecin differ from those of chitin-binding proteins in other invertebrates and plants, suggesting that scarabaecin does not share a common ancestor with them. These results are thought to provide further strong experimental evidence to the hypothesis that chitin-binding proteins of invertebrates and plants are correlated by a convergent evolution process.
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Affiliation(s)
- Hikaru Hemmi
- National Food Research Institute, 2-1-12 Kannondai, Tsukuba, Ibaraki 305-8642, Japan.
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Olson LJ, Zhang J, Dahms NM, Kim JJP. Twists and turns of the cation-dependent mannose 6-phosphate receptor. Ligand-bound versus ligand-free receptor. J Biol Chem 2002; 277:10156-61. [PMID: 11786557 DOI: 10.1074/jbc.m112230200] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mannose 6-phosphate receptors (MPRs) participate in the biogenesis of lysosomes in higher eukaryotes by transporting soluble acid hydrolases from the trans-Golgi network to late endosomal compartments. The receptors release their ligands into the acidic environment of the late endosome and then return to the trans-Golgi network to repeat the process. However, the mechanism that facilitates ligand binding and dissociation upon changes in pH is not known. We report the crystal structure of the extracytoplasmic domain of the homodimeric cation-dependent MPR in a ligand-free form at pH 6.5. A comparison of the ligand-bound and ligand-free structures reveals a significant change in quaternary structure as well as a reorganization of the binding pocket, with the most prominent change being the relocation of a loop (residues Glu(134)-Cys(141)). The movements involved in the bound-to-free transition of the cation-dependent MPR are reminiscent of those of the oxy-to-deoxy hemoglobin transition. These results allow us to propose a mechanism by which the receptor regulates its ligand binding upon changes in pH; the pK(a) of Glu(133) appears to be responsible for ligand release in the acidic environment of the late endosomal compartment, and the pK(a) values of the sugar phosphate and His(105) are accountable for its inability to bind ligand at the cell surface where the pH is about 7.4.
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Affiliation(s)
- Linda J Olson
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA
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