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Schröder L, Hohnjec N, Senkler M, Senkler J, Küster H, Braun HP. The gene space of European mistletoe (Viscum album). THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 109:278-294. [PMID: 34713513 DOI: 10.1111/tpj.15558] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 09/28/2021] [Accepted: 10/01/2021] [Indexed: 06/13/2023]
Abstract
European mistletoe (Viscum album) is a hemiparasitic flowering plant that is known for its very special life cycle and extraordinary biochemical properties. Particularly, V. album has an unusual mode of cellular respiration that takes place in the absence of mitochondrial complex I. However, insights into the molecular biology of V. album so far are very limited. Since the genome of V. album is extremely large (estimated 600 times larger than the genome of the model plant Arabidopsis thaliana) it has not been sequenced up to now. We here report sequencing of the V. album gene space (defined as the space including and surrounding genic regions, encompassing coding as well as 5' and 3' non-coding regions). mRNA fractions were isolated from different V. album organs harvested in summer or winter and were analyzed via single-molecule real-time sequencing. We determined sequences of 39 092 distinct open reading frames encoding 32 064 V. album proteins (designated V. album protein space). Our data give new insights into the metabolism and molecular biology of V. album, including the biosynthesis of lectins and viscotoxins. The benefits of the V. album gene space information are demonstrated by re-evaluating mass spectrometry-based data of the V. album mitochondrial proteome, which previously had been evaluated using the A. thaliana genome sequence. Our re-examination allowed the additional identification of nearly 200 mitochondrial proteins, including four proteins related to complex I, which all have a secondary function not related to respiratory electron transport. The V. album gene space sequences are available at the NCBI.
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Affiliation(s)
- Lucie Schröder
- Plant Proteomics, Institute of Plant Genetics, Leibniz Universität Hannover, Herrenhäuser Str. 2, 30419, Hannover, Germany
| | - Natalija Hohnjec
- Plant Genomics, Institute of Plant Genetics, Leibniz Universität Hannover, Herrenhäuser Str. 2, 30419, Hannover, Germany
| | - Michael Senkler
- Plant Proteomics, Institute of Plant Genetics, Leibniz Universität Hannover, Herrenhäuser Str. 2, 30419, Hannover, Germany
| | - Jennifer Senkler
- Plant Proteomics, Institute of Plant Genetics, Leibniz Universität Hannover, Herrenhäuser Str. 2, 30419, Hannover, Germany
| | - Helge Küster
- Plant Genomics, Institute of Plant Genetics, Leibniz Universität Hannover, Herrenhäuser Str. 2, 30419, Hannover, Germany
| | - Hans-Peter Braun
- Plant Proteomics, Institute of Plant Genetics, Leibniz Universität Hannover, Herrenhäuser Str. 2, 30419, Hannover, Germany
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Snell EH, Helliwell JR. Microgravity as an environment for macromolecular crystallization – an outlook in the era of space stations and commercial space flight. CRYSTALLOGR REV 2021. [DOI: 10.1080/0889311x.2021.1900833] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- E. H. Snell
- Hauptman-Woodward Medical Research Institute, Buffalo, NY, USA
- Materials Design and Innovation Department, SUNY Buffalo, Buffalo, NY, USA
| | - J. R. Helliwell
- Chemistry Department, University of Manchester, Manchester, UK
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Gengenbach BB, Keil LL, Opdensteinen P, Müschen CR, Melmer G, Lentzen H, Bührmann J, Buyel JF. Comparison of microbial and transient expression (tobacco plants and plant-cell packs) for the production and purification of the anticancer mistletoe lectin viscumin. Biotechnol Bioeng 2019; 116:2236-2249. [PMID: 31140580 PMCID: PMC6772165 DOI: 10.1002/bit.27076] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 05/14/2019] [Accepted: 05/23/2019] [Indexed: 01/02/2023]
Abstract
Cancer is the leading cause of death in industrialized countries. Cancer therapy often involves monoclonal antibodies or small-molecule drugs, but carbohydrate-binding lectins such as mistletoe (Viscum album) viscumin offer a potential alternative treatment strategy. Viscumin is toxic in mammalian cells, ruling them out as an efficient production system, and it forms inclusion bodies in Escherichia coli such that purification requires complex and lengthy refolding steps. We therefore investigated the transient expression of viscumin in intact Nicotiana benthamiana plants and Nicotiana tabacum Bright Yellow 2 plant-cell packs (PCPs), comparing a full-length viscumin gene construct to separate constructs for the A and B chains. As determined by capillary electrophoresis the maximum yield of purified heterodimeric viscumin in N. benthamiana was ~7 mg/kg fresh biomass with the full-length construct. The yield was about 50% higher in PCPs but reduced 10-fold when coexpressing A and B chains as individual polypeptides. Using a single-step lactosyl-Sepharose affinity resin, we purified viscumin to ~54%. The absence of refolding steps resulted in estimated cost savings of more than 80% when transient expression in tobacco was compared with E. coli. Furthermore, the plant-derived product was ~3-fold more toxic than the bacterially produced counterpart. We conclude that plants offer a suitable alternative for the production of complex biopharmaceutical proteins that are toxic to mammalian cells and that form inclusion bodies in bacteria.
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MESH Headings
- Antineoplastic Agents, Phytogenic/biosynthesis
- Antineoplastic Agents, Phytogenic/isolation & purification
- Escherichia coli/genetics
- Escherichia coli/metabolism
- Gene Expression
- Plant Cells/metabolism
- Plant Proteins/biosynthesis
- Plant Proteins/genetics
- Plant Proteins/isolation & purification
- Plants, Genetically Modified/genetics
- Plants, Genetically Modified/metabolism
- Recombinant Proteins/biosynthesis
- Recombinant Proteins/genetics
- Recombinant Proteins/isolation & purification
- Ribosome Inactivating Proteins, Type 2/biosynthesis
- Ribosome Inactivating Proteins, Type 2/genetics
- Ribosome Inactivating Proteins, Type 2/isolation & purification
- Nicotiana/genetics
- Nicotiana/metabolism
- Toxins, Biological/biosynthesis
- Toxins, Biological/genetics
- Toxins, Biological/isolation & purification
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Affiliation(s)
- Benjamin B. Gengenbach
- Integrated Production PlatformsFraunhofer Institute for Molecular Biology and Applied Ecology IMEAachenGermany
- Institute for Molecular BiotechnologyRWTH Aachen UniversityAachenGermany
| | - Linda L. Keil
- Institute for Molecular BiotechnologyRWTH Aachen UniversityAachenGermany
| | - Patrick Opdensteinen
- Integrated Production PlatformsFraunhofer Institute for Molecular Biology and Applied Ecology IMEAachenGermany
- Institute for Molecular BiotechnologyRWTH Aachen UniversityAachenGermany
| | - Catherine R. Müschen
- Integrated Production PlatformsFraunhofer Institute for Molecular Biology and Applied Ecology IMEAachenGermany
- Institute for Molecular BiotechnologyRWTH Aachen UniversityAachenGermany
| | | | | | | | - Johannes F. Buyel
- Integrated Production PlatformsFraunhofer Institute for Molecular Biology and Applied Ecology IMEAachenGermany
- Institute for Molecular BiotechnologyRWTH Aachen UniversityAachenGermany
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Boyko KM, Timofeev VI, Samygina VR, Kuranova IP, Popov VO, Koval’chuk MV. Protein crystallization under microgravity conditions. Analysis of the results of Russian experiments performed on the International Space Station in 2005−2015. CRYSTALLOGR REP+ 2016. [DOI: 10.1134/s1063774516050059] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Owens GE, New DM, Olvera AI, Manzella JA, Macon BL, Dunn JC, Cooper DA, Rouleau RL, Connor DS, Bjorkman PJ. Comparative analysis of anti-polyglutamine Fab crystals grown on Earth and in microgravity. Acta Crystallogr F Struct Biol Commun 2016; 72:762-771. [PMID: 27710941 PMCID: PMC5053161 DOI: 10.1107/s2053230x16014011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 09/02/2016] [Indexed: 11/10/2022] Open
Abstract
Huntington's disease is one of nine neurodegenerative diseases caused by a polyglutamine (polyQ)-repeat expansion. An anti-polyQ antigen-binding fragment, MW1 Fab, was crystallized both on Earth and on the International Space Station, a microgravity environment where convection is limited. Once the crystals returned to Earth, the number, size and morphology of all crystals were recorded, and X-ray data were collected from representative crystals. The results generally agreed with previous microgravity crystallization studies. On average, microgravity-grown crystals were 20% larger than control crystals grown on Earth, and microgravity-grown crystals had a slightly improved mosaicity (decreased by 0.03°) and diffraction resolution (decreased by 0.2 Å) compared with control crystals grown on Earth. However, the highest resolution and lowest mosaicity crystals were formed on Earth, and the highest-quality crystal overall was formed on Earth after return from microgravity.
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Affiliation(s)
- Gwen E. Owens
- Division of Biology and Biological Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA
- Graduate Option in Biochemistry and Molecular Biophysics, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA
- UCLA–Caltech Medical Scientist Training Program, Los Angeles, CA 90095, USA
| | - Danielle M. New
- Division of Biology and Biological Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA
| | - Alejandra I. Olvera
- Division of Biology and Biological Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA
| | - Julia Ashlyn Manzella
- Center for Biophysical Sciences and Engineering, University of Alabama at Birmingham, 1025 18th Street South, Birmingham, AL 35294, USA
| | - Brittney L. Macon
- Center for Biophysical Sciences and Engineering, University of Alabama at Birmingham, 1025 18th Street South, Birmingham, AL 35294, USA
| | - Joshua C. Dunn
- Center for Biophysical Sciences and Engineering, University of Alabama at Birmingham, 1025 18th Street South, Birmingham, AL 35294, USA
| | - David A. Cooper
- Center for Biophysical Sciences and Engineering, University of Alabama at Birmingham, 1025 18th Street South, Birmingham, AL 35294, USA
| | - Robyn L. Rouleau
- Center for Biophysical Sciences and Engineering, University of Alabama at Birmingham, 1025 18th Street South, Birmingham, AL 35294, USA
| | - Daniel S. Connor
- Center for Biophysical Sciences and Engineering, University of Alabama at Birmingham, 1025 18th Street South, Birmingham, AL 35294, USA
| | - Pamela J. Bjorkman
- Division of Biology and Biological Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA
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Boyko KM, Popov VO, Kovalchuk MV. Promising approaches to crystallization of macromolecules suppressing the convective mass transport to the growing crystal. RUSSIAN CHEMICAL REVIEWS 2015. [DOI: 10.1070/rcr4557] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Sharma A, Pohlentz G, Bobbili KB, Jeyaprakash AA, Chandran T, Mormann M, Swamy MJ, Vijayan M. The sequence and structure of snake gourd (Trichosanthes anguina) seed lectin, a three-chain nontoxic homologue of type II RIPs. ACTA CRYSTALLOGRAPHICA SECTION D: BIOLOGICAL CRYSTALLOGRAPHY 2013; 69:1493-503. [PMID: 23897472 DOI: 10.1107/s0907444913010020] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Accepted: 04/11/2013] [Indexed: 11/10/2022]
Abstract
The sequence and structure of snake gourd seed lectin (SGSL), a nontoxic homologue of type II ribosome-inactivating proteins (RIPs), have been determined by mass spectrometry and X-ray crystallography, respectively. As in type II RIPs, the molecule consists of a lectin chain made up of two β-trefoil domains. The catalytic chain, which is connected through a disulfide bridge to the lectin chain in type II RIPs, is cleaved into two in SGSL. However, the integrity of the three-dimensional structure of the catalytic component of the molecule is preserved. This is the first time that a three-chain RIP or RIP homologue has been observed. A thorough examination of the sequence and structure of the protein and of its interactions with the bound methyl-α-galactose indicate that the nontoxicity of SGSL results from a combination of changes in the catalytic and the carbohydrate-binding sites. Detailed analyses of the sequences of type II RIPs of known structure and their homologues with unknown structure provide valuable insights into the evolution of this class of proteins. They also indicate some variability in carbohydrate-binding sites, which appears to contribute to the different levels of toxicity exhibited by lectins from various sources.
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Affiliation(s)
- Alok Sharma
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012, Karnataka, India
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Bogoeva V, Ivanov I, Kulina H, Russev G, Atanasova L. A Novel Cytokinin-Binding Property of Mistletoe Lectin I from Viscum Album. BIOTECHNOL BIOTEC EQ 2013. [DOI: 10.5504/bbeq.2012.0116] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Małecki PH, Rypniewski W, Szymański M, Barciszewski J, Meyer A. Binding of the plant hormone kinetin in the active site of Mistletoe Lectin I from Viscum album. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2011; 1824:334-8. [PMID: 22064121 DOI: 10.1016/j.bbapap.2011.10.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2011] [Revised: 10/13/2011] [Accepted: 10/17/2011] [Indexed: 10/15/2022]
Abstract
The crystal structure of the ribosome inhibiting protein Mistletoe Lectin I (ML-I) derived from the European mistletoe, Viscum album, in complex with kinetin has been refined at 2.7Å resolution. Suitably large crystals of ML-I were obtained applying the counter diffusion method using the Gel Tube R Crystallization Kit (GT-R) on board the Russian Service Module on the international space station ISS within the GCF mission No. 6, arranged by the Japanese aerospace exploration agency (JAXA). Hexagonal bi-pyramidal crystals were grown during three months under microgravity. Before data collection the crystals were soaked in a saturated solution of kinetin and diffraction data to 2.7Å were collected using synchrotron radiation and cryogenic techniques. The atomic model was refined and revealed a single kinetin molecule in the ribosome inactivation site of ML-I. The complex demonstrates the feasibility of mistletoe to bind plant hormones out of the host regulation system as part of a self protection mechanism.
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Affiliation(s)
- Piotr H Małecki
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznan, Poland
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Maveyraud L, Niwa H, Guillet V, Svergun DI, Konarev PV, Palmer RA, Peumans WJ, Rougé P, Van Damme EJM, Reynolds CD, Mourey L. Structural basis for sugar recognition, including the Tn carcinoma antigen, by the lectin SNA-II from Sambucus nigra. Proteins 2009; 75:89-103. [PMID: 18798567 DOI: 10.1002/prot.22222] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Bark of elderberry (Sambucus nigra) contains a galactose (Gal)/N-acetylgalactosamine (GalNAc)-specific lectin (SNA-II) corresponding to slightly truncated B-chains of a genuine Type-II ribosome-inactivating protein (Type-II RIPs, SNA-V), found in the same species. The three-dimensional X-ray structure of SNA-II has been determined in two distinct crystal forms, hexagonal and tetragonal, at 1.90 A and 1.35 A, respectively. In both crystal forms, the SNA-II molecule folds into two linked beta-trefoil domains, with an overall conformation similar to that of the B-chains of ricin and other Type-II RIPs. Glycosylation is observed at four sites along the polypeptide chain, accounting for 14 saccharide units. The high-resolution structures of SNA-II in complex with Gal and five Gal-related saccharides (GalNAc, lactose, alpha1-methylgalactose, fucose, and the carcinoma-specific Tn antigen) were determined at 1.55 A resolution or better. Binding is observed in two saccharide-binding sites for most of the sugars: a conserved aspartate residue interacts simultaneously with the O3 and O4 atoms of saccharides. In one of the binding sites, additional interactions with the protein involve the O6 atom. Analytical gel filtration, small angle X-ray scattering studies and crystal packing analysis indicate that, although some oligomeric species are present, the monomeric species predominate in solution.
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Affiliation(s)
- Laurent Maveyraud
- Institut de Pharmacologie et de Biologie Structurale (IPBS), UMR 5089, Université Paul Sabatier Toulouse III/CNRS, Toulouse, France.
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Meyer A, Rypniewski W, Szymański M, Voelter W, Barciszewski J, Betzel C. Structure of mistletoe lectin I from Viscum album in complex with the phytohormone zeatin. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2008; 1784:1590-5. [DOI: 10.1016/j.bbapap.2008.07.010] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/29/2008] [Revised: 07/18/2008] [Accepted: 07/18/2008] [Indexed: 10/21/2022]
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13
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Meyer A, Rypniewski W, Celewicz L, Erdmann VA, Voelter W, Singh TP, Genov N, Barciszewski J, Betzel C. The mistletoe lectin I--phloretamide structure reveals a new function of plant lectins. Biochem Biophys Res Commun 2007; 364:195-200. [PMID: 17937929 DOI: 10.1016/j.bbrc.2007.09.113] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2007] [Accepted: 09/24/2007] [Indexed: 10/22/2022]
Abstract
The X-ray structure at 2.7A resolution of the complex between the European mistletoe lectin I (Viscum album, ML-I) and the plant growth hormone, 3-(p-hydroxyphenyl)-propionic acid amide (phloretamide, PA) from xylem sap has revealed the binding of PA at the so far undescribed hydrophobic cavity located between the two subunits of this ribosome-inhibiting protein. No such cavity is observed in related lectins. The binding of PA is achieved through interactions with the non-conserved residues Val228A, Leu230A, Arg388B, and the C-terminal Pro510B. It is conceivable that binding of PA to ML-I is part of a defence mechanism of the parasite against the host, whereby the parasite prevents the growth hormone of the host from interfering with its own regulatory system. The specific binding of PA to ML-I indicates that heterodimeric RIPs are multifunctional proteins whose functions in the cell have not yet been fully recognized and analyzed.
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Affiliation(s)
- A Meyer
- Institute of Biochemistry and Molecular Biology, University of Hamburg, c/o DESY, Notkestr. 85, Building 22a, 22603 Hamburg, Germany
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Fraser ME, Cherney MM, Marcato P, Mulvey GL, Armstrong GD, James MNG. Binding of adenine to Stx2, the protein toxin from Escherichia coli O157:H7. Acta Crystallogr Sect F Struct Biol Cryst Commun 2006; 62:627-30. [PMID: 16820678 PMCID: PMC2242964 DOI: 10.1107/s1744309106021968] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2006] [Accepted: 06/09/2006] [Indexed: 11/10/2022]
Abstract
Stx2 is a protein toxin whose catalytic subunit acts as an N-glycosidase to depurinate a specific adenine base from 28S rRNA. In the holotoxin, the catalytic portion, A1, is linked to the rest of the A subunit, A2, and A2 interacts with the pentameric ring formed by the five B subunits. In order to test whether the holotoxin is active as an N-glycosidase, Stx2 was crystallized in the presence of adenosine and adenine. The crystals diffracted to approximately 1.8 angstroms and showed clear electron density for adenine in the active site. Adenosine had been cleaved, proving that Stx2 is an active N-glycosidase. While the holotoxin is active against small substrates, it would be expected that the B subunits would interfere with the binding of the 28S rRNA.
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Affiliation(s)
- Marie E Fraser
- Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary AB T2N 1N4, Canada.
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Mikeska R, Wacker R, Arni R, Singh TP, Mikhailov A, Gabdoulkhakov A, Voelter W, Betzel C. Mistletoe lectin I in complex with galactose and lactose reveals distinct sugar-binding properties. Acta Crystallogr Sect F Struct Biol Cryst Commun 2004; 61:17-25. [PMID: 16508080 PMCID: PMC1952410 DOI: 10.1107/s1744309104031501] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2004] [Accepted: 11/29/2004] [Indexed: 11/10/2022]
Abstract
The structures of mistletoe lectin I (ML-I) from Viscum album complexed with lactose and galactose have been determined at 2.3 A resolution and refined to R factors of 20.9% (Rfree = 23.6%) and 20.9 (Rfree = 24.6%), respectively. ML-I is a heterodimer and belongs to the class of ribosome-inactivating proteins of type II, which consist of two chains. The A-chain has rRNA N-glycosidase activity and irreversibly inhibits eukaryotic ribosomes. The B-chain is a lectin and preferentially binds to galactose-terminated glycolipids and glycoproteins on cell membranes. Saccharide binding is performed by two binding sites in subdomains alpha1 and gamma2 of the ML-I B-chain separated by approximately 62 A from each other. The favoured binding of galactose in subdomain alpha1 is achieved via hydrogen bonds connecting the 4-hydroxyl and 3-hydroxyl groups of the sugar moiety with the side chains of Asp23B, Gln36B and Lys41B and the main chain of 26B. The aromatic ring of Trp38B on top of the preferred binding pocket supports van der Waals packing of the apolar face of galactose and stabilizes the sugar-lectin complex. In the galactose-binding site II of subdomain gamma2, Tyr249B provides the hydrophobic stacking and the side chains of Asp235B, Gln238B and Asn256B are hydrogen-bonding partners for galactose. In the case of the galactose-binding site I, the 2-hydroxyl group also stabilizes the sugar-protein complex, an interaction thus far rarely detected in galactose-specific lectins. Finally, a potential third low-affinity galactose-binding site in subunit beta1 was identified in the present ML-I structures, in which a glycerol molecule from the cryoprotectant buffer has bound, mimicking the sugar compound.
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Affiliation(s)
- Ruth Mikeska
- Institute of Biochemistry and Food Chemistry, University of Hamburg, c/o DESY, Notkestrasse 85, Building 22a, 22603 Hamburg, Germany
| | - Roland Wacker
- Institute of Physiological Chemistry, University of Tübingen, Hoppe-Seyler-Strasse 4, 72076 Tübingen, Germany
| | - Raghuvir Arni
- Department of Physics, IBILCE/UNESP, São Jose do Rio Preto, São Paul, Brazil
| | - Tej P. Singh
- Department of Biophysics, All India Institute of Medical Sciences, New Delhi, India
| | - Albert Mikhailov
- Institute of Crystallography of Russian Academy of Sciences, Leninsky Prospect 59, 117333 Moscow, Russia
| | - Azat Gabdoulkhakov
- Institute of Crystallography of Russian Academy of Sciences, Leninsky Prospect 59, 117333 Moscow, Russia
| | - Wolfgang Voelter
- Institute of Physiological Chemistry, University of Tübingen, Hoppe-Seyler-Strasse 4, 72076 Tübingen, Germany
| | - Christian Betzel
- Institute of Biochemistry and Food Chemistry, University of Hamburg, c/o DESY, Notkestrasse 85, Building 22a, 22603 Hamburg, Germany
- Correspondence e-mail:
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