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Irwin J. Goldstein - One of the best experts on this subject based on the ideXlab platform.
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Isolation and characterization of a Forssman Antigen-binding lectin from velvet bean (Mucuna derringiana) seeds
Glycoconjugate Journal, 1994Co-Authors: Irwin J. GoldsteinAbstract:A Forssman Antigen (GalNAcα1-3GalNAcβ1-3Galα1-4Galβ1-4Glcβ1-1Cer)-binding lectin has been purified from velvet bean ( Mucuna derringiana ) seeds by a combination of affinity chromatography and reversed phase HPLC. This lectin agglutinates both native and trypsin-treated sheep erythrocytes as well as trypsinized rabbit erythrocytes, but neither native rabbit nor human erythrocytes, irrespective of blood group type. SDS-PAGE and gel filtration chromatography reveal the lectin to be a homodimer consisting of two 54 kDa subunits linked by non-covalent bonds. The results obtained by quantitative precipitation, haemagglutination inhibition and TLC overlay assays indicate that the Mucuna lectin specifically recognizes Forssman Antigen and Forssman disaccharide (GalNAcα1-3GalNAc)-related structures.
Fumiichiro Yamamoto - One of the best experts on this subject based on the ideXlab platform.
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Crosstalk between ABO and Forssman (FORS) blood group systems: FORS1 Antigen synthesis by ABO gene-encoded glycosyltransferases.
Scientific reports, 2017Co-Authors: Miyako Yamamoto, Emili Cid, Fumiichiro YamamotoAbstract:A and B alleles at the ABO genetic locus specify A and B glycosyltransferases that catalyze the biosynthesis of A and B oligosaccharide Antigens, respectively, of blood group ABO system which is important in transfusion and transplantation medicine. GBGT1 gene encodes Forssman glycolipid synthase (FS), another glycosyltransferase that produces Forssman Antigen (FORS1). Humans are considered to be Forssman Antigen-negative species without functional FS. However, rare individuals exhibiting Apae phenotype carry a dominant active GBGT1 gene and express Forssman Antigen on RBCs. Accordingly, FORS system was recognized as the 31st blood group system. Mouse ABO gene encodes a cis-AB transferase capable of producing both A and B Antigens. This murine enzyme contains the same GlyGlyAla tripeptide sequence as FSs at the position important for the determination of sugar specificity. We, therefore, transfected the expression construct into appropriate recipient cells and examined whether mouse cis-AB transferase may also exhibit FS activity. The result was positive, confirming the crosstalk between the ABO and FORS systems. Further experiments have revealed that the introduction of this tripeptide sequence to human A transferase conferred some, although weak, FS activity, suggesting that it is also involved in the recognition/binding of acceptor substrates, in addition to donor nucleotide-sugars.
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Glycan immunocytochemistry of triple positive cells geared towards the synthesis of SSEA-3 and Forssman Antigens.
2013Co-Authors: Emili Cid, Miyako Yamamoto, Marcus Buschbeck, Fumiichiro YamamotoAbstract:DAB staining using the ABC immunocytochemical system of sorted triple positive cells. Genotypes are described in the horizontal axis while the antibodies and staining procedures are organized on the vertical axis. The “No antibody” row corresponds to staining only with secondary antibody. The SSEA-3 staining was performed using the MC361 antibody. The Forssman Antigen was detected with FOM-1 antibody. All images were taken at the same magnification.
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Molecular genetic basis of the human Forssman glycolipid Antigen negativity
Scientific reports, 2012Co-Authors: Miyako Yamamoto, Emili Cid, Fumiichiro YamamotoAbstract:Forssman heterophilic glycolipid Antigen has structural similarity to the histo-blood group A Antigen, and the GBGT1 gene encoding the Forssman glycolipid synthetase (FS) is evolutionarily related to the ABO gene. The Antigen is present in various species, but not in others including humans. We have elucidated the molecular genetic basis of the Forssman Antigen negativity in humans. In the human GBGT1 gene, we identified two common inactivating missense mutations (c.688G>A [p.Gly230Ser] and c.887A>G [p.Gln296Arg]). The reversion of the two mutations fully restored the glycosyltransferase activity to synthesize the Forssman Antigen in vitro. These glycine and glutamine residues are conserved among functional GBGT1 genes in Forssman-positive species. Furthermore, the glycine and serine residues represent those at the corresponding position of the human blood group A and B transferases with GalNAc and galactose specificity, respectively, implicating the crucial role the glycine residue may play in the FS α1,3-GalNAc transferase activity.
Miyako Yamamoto - One of the best experts on this subject based on the ideXlab platform.
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Crosstalk between ABO and Forssman (FORS) blood group systems: FORS1 Antigen synthesis by ABO gene-encoded glycosyltransferases.
Scientific reports, 2017Co-Authors: Miyako Yamamoto, Emili Cid, Fumiichiro YamamotoAbstract:A and B alleles at the ABO genetic locus specify A and B glycosyltransferases that catalyze the biosynthesis of A and B oligosaccharide Antigens, respectively, of blood group ABO system which is important in transfusion and transplantation medicine. GBGT1 gene encodes Forssman glycolipid synthase (FS), another glycosyltransferase that produces Forssman Antigen (FORS1). Humans are considered to be Forssman Antigen-negative species without functional FS. However, rare individuals exhibiting Apae phenotype carry a dominant active GBGT1 gene and express Forssman Antigen on RBCs. Accordingly, FORS system was recognized as the 31st blood group system. Mouse ABO gene encodes a cis-AB transferase capable of producing both A and B Antigens. This murine enzyme contains the same GlyGlyAla tripeptide sequence as FSs at the position important for the determination of sugar specificity. We, therefore, transfected the expression construct into appropriate recipient cells and examined whether mouse cis-AB transferase may also exhibit FS activity. The result was positive, confirming the crosstalk between the ABO and FORS systems. Further experiments have revealed that the introduction of this tripeptide sequence to human A transferase conferred some, although weak, FS activity, suggesting that it is also involved in the recognition/binding of acceptor substrates, in addition to donor nucleotide-sugars.
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Glycan immunocytochemistry of triple positive cells geared towards the synthesis of SSEA-3 and Forssman Antigens.
2013Co-Authors: Emili Cid, Miyako Yamamoto, Marcus Buschbeck, Fumiichiro YamamotoAbstract:DAB staining using the ABC immunocytochemical system of sorted triple positive cells. Genotypes are described in the horizontal axis while the antibodies and staining procedures are organized on the vertical axis. The “No antibody” row corresponds to staining only with secondary antibody. The SSEA-3 staining was performed using the MC361 antibody. The Forssman Antigen was detected with FOM-1 antibody. All images were taken at the same magnification.
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Molecular genetic basis of the human Forssman glycolipid Antigen negativity
Scientific reports, 2012Co-Authors: Miyako Yamamoto, Emili Cid, Fumiichiro YamamotoAbstract:Forssman heterophilic glycolipid Antigen has structural similarity to the histo-blood group A Antigen, and the GBGT1 gene encoding the Forssman glycolipid synthetase (FS) is evolutionarily related to the ABO gene. The Antigen is present in various species, but not in others including humans. We have elucidated the molecular genetic basis of the Forssman Antigen negativity in humans. In the human GBGT1 gene, we identified two common inactivating missense mutations (c.688G>A [p.Gly230Ser] and c.887A>G [p.Gln296Arg]). The reversion of the two mutations fully restored the glycosyltransferase activity to synthesize the Forssman Antigen in vitro. These glycine and glutamine residues are conserved among functional GBGT1 genes in Forssman-positive species. Furthermore, the glycine and serine residues represent those at the corresponding position of the human blood group A and B transferases with GalNAc and galactose specificity, respectively, implicating the crucial role the glycine residue may play in the FS α1,3-GalNAc transferase activity.
Emili Cid - One of the best experts on this subject based on the ideXlab platform.
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Crosstalk between ABO and Forssman (FORS) blood group systems: FORS1 Antigen synthesis by ABO gene-encoded glycosyltransferases.
Scientific reports, 2017Co-Authors: Miyako Yamamoto, Emili Cid, Fumiichiro YamamotoAbstract:A and B alleles at the ABO genetic locus specify A and B glycosyltransferases that catalyze the biosynthesis of A and B oligosaccharide Antigens, respectively, of blood group ABO system which is important in transfusion and transplantation medicine. GBGT1 gene encodes Forssman glycolipid synthase (FS), another glycosyltransferase that produces Forssman Antigen (FORS1). Humans are considered to be Forssman Antigen-negative species without functional FS. However, rare individuals exhibiting Apae phenotype carry a dominant active GBGT1 gene and express Forssman Antigen on RBCs. Accordingly, FORS system was recognized as the 31st blood group system. Mouse ABO gene encodes a cis-AB transferase capable of producing both A and B Antigens. This murine enzyme contains the same GlyGlyAla tripeptide sequence as FSs at the position important for the determination of sugar specificity. We, therefore, transfected the expression construct into appropriate recipient cells and examined whether mouse cis-AB transferase may also exhibit FS activity. The result was positive, confirming the crosstalk between the ABO and FORS systems. Further experiments have revealed that the introduction of this tripeptide sequence to human A transferase conferred some, although weak, FS activity, suggesting that it is also involved in the recognition/binding of acceptor substrates, in addition to donor nucleotide-sugars.
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Glycan immunocytochemistry of triple positive cells geared towards the synthesis of SSEA-3 and Forssman Antigens.
2013Co-Authors: Emili Cid, Miyako Yamamoto, Marcus Buschbeck, Fumiichiro YamamotoAbstract:DAB staining using the ABC immunocytochemical system of sorted triple positive cells. Genotypes are described in the horizontal axis while the antibodies and staining procedures are organized on the vertical axis. The “No antibody” row corresponds to staining only with secondary antibody. The SSEA-3 staining was performed using the MC361 antibody. The Forssman Antigen was detected with FOM-1 antibody. All images were taken at the same magnification.
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Molecular genetic basis of the human Forssman glycolipid Antigen negativity
Scientific reports, 2012Co-Authors: Miyako Yamamoto, Emili Cid, Fumiichiro YamamotoAbstract:Forssman heterophilic glycolipid Antigen has structural similarity to the histo-blood group A Antigen, and the GBGT1 gene encoding the Forssman glycolipid synthetase (FS) is evolutionarily related to the ABO gene. The Antigen is present in various species, but not in others including humans. We have elucidated the molecular genetic basis of the Forssman Antigen negativity in humans. In the human GBGT1 gene, we identified two common inactivating missense mutations (c.688G>A [p.Gly230Ser] and c.887A>G [p.Gln296Arg]). The reversion of the two mutations fully restored the glycosyltransferase activity to synthesize the Forssman Antigen in vitro. These glycine and glutamine residues are conserved among functional GBGT1 genes in Forssman-positive species. Furthermore, the glycine and serine residues represent those at the corresponding position of the human blood group A and B transferases with GalNAc and galactose specificity, respectively, implicating the crucial role the glycine residue may play in the FS α1,3-GalNAc transferase activity.
Mitsuru Jimbo - One of the best experts on this subject based on the ideXlab platform.
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Crystal structure of octocoral lectin SLL-2 complexed with Forssman Antigen tetrasaccharide.
Glycobiology, 2017Co-Authors: Akiko Kita, Mitsuru Jimbo, Ryuichi Sakai, Yukio Morimoto, Ryota Takeuchi, Hiroshi Tanaka, Takashi Takahashi, Kunio MikiAbstract:A symbiosis-related lectin, SLL-2, from the octocoral Sinularia lochmodes, distributes densely on the cell surface of microalgae, Symbiodinium sp., an endosymbiotic dinoflagellate of the coral, and is also shown to be a chemical cue that transforms dinoflagellates into a nonmotile (coccoid) symbiotic state. SLL-2 binds to the sugar chain of the molecule similar to Forssman Antigen pentasaccharide (GalNAcα1-3GalNAcβ1-3 Galα1-4 Galβ1-4Glc) on the surface of microalgae with high affinity. Here we report the crystal structure of the complex between SLL-2 and Forssman Antigen tetrasaccharide (GalNAcα1-3GalNAcβ1-3 Galα1-4 Galβ) at 3.4 A resolution. In an asymmetric unit of the crystal, there are two hexameric molecules with totally 12 sugar recognition sites. At 9 in 12 sites, the first and second saccharides of the Forssman Antigen tetrasaccharide bind directly to galactopyranoside binding site of SLL-2, whereas the third and fourth saccharides have no interaction with the SLL-2 hexameric molecule that binds the first saccharide. The sugar chain bends at α-1,4-glycosidic linkage between the third and fourth saccharides toward the position that we defined as a pyranoside binding site in the crystal structure of the complex between SLL-2 and GalNAc. The structure allowed us to suggest a possible binding mode of the Forssman Antigen pentasaccharide to SLL-2. These observations support our hypothesis that the binding of SLL-2 to the cell surface sugars of zooxanthella in a unique manner might trigger some physiological changes of the cell to adapt symbiosis with the host coral.
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Crystal structure of a symbiosis-related lectin from octocoral.
Glycobiology, 2015Co-Authors: Akiko Kita, Mitsuru Jimbo, Ryuichi Sakai, Yukio Morimoto, Kunio MikiAbstract:D-Galactose-binding lectin from the octocoral, Sinularia lochmodes (SLL-2), distributes densely on the cell surface of microalgae, Symbiodinium sp., an endosymbiotic dinoflagellate of the coral, and is also shown to be a chemical cue that transforms dinoflagellate into a non-motile (coccoid) symbiotic state. SLL-2 binds with high affinity to the Forssman Antigen (N-acetylgalactosamine(GalNAc)α1-3GalNAcβ1-3Galα1-4Galβ1-4Glc-ceramide), and the presence of Forssman Antigen-like sugar on the surface of Symbiodinium CS-156 cells was previously confirmed. Here we report the crystal structures of SLL-2 and its GalNAc complex as the first crystal structures of a lectin involved in the symbiosis between coral and dinoflagellate. N-Linked sugar chains and a galactose derivative binding site common to H-type lectins were observed in each monomer of the hexameric SLL-2 crystal structure. In addition, unique sugar-binding site-like regions were identified at the top and bottom of the hexameric SLL-2 structure. These structural features suggest a possible binding mode between SLL-2 and Forssman Antigen-like pentasaccharide.
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synthesis and biological evaluation of the Forssman Antigen pentasaccharide and derivatives by a one pot glycosylation procedure
Chemistry: A European Journal, 2013Co-Authors: Hiroshi Tanaka, Mitsuru Jimbo, Ryota Takeuchi, Nami Kuniya, Takashi TakahashiAbstract:The synthesis and biological evaluation of the Forssman Antigen pentasaccharide and derivatives thereof by using a one-pot glycosylation and polymer-assisted deprotection is described. The Forssman Antigen pentasaccharide, composed of GalNAcα(1,3)GalNAcβ(1,3)Galα(1,4)Galβ(1,4)Glc, was recently identified as a ligand of the lectin SLL-2 isolated from an octocoral Sinularia lochmodes. The chemo- and α-selective glycosylation of a thiogalactoside with a hemiacetal donor by using a mixture of Tf(2)O, TTBP and Ph(2)SO, followed by activation of the remaining thioglycoside, provided the trisaccharide at the reducing end in a one-pot procedure. The pentasaccharide was prepared by the α-selective glycosylation of the N-Troc-protected (Troc=2,2,2-trichloroethoxycarbonyl) thioglycoside with a 2-azide-1-hydroxyl glycosyl donor, followed by glycosidation of the resulting disaccharide at the C3 hydroxyl group of the trisaccharide acceptor in a one-pot process. We next applied the one-pot glycosylation method to the synthesis of pentasaccharides in which the galactosamine units were partially and fully replaced by galactose units. Among the three possible pentasaccharides, Galα(1,3)GalNAc and Galα(1,3)Gal derivatives were successfully prepared by the established method. An assay of the binding of the synthetic oligosaccharides to a fluorescent-labeled SLL-2 revealed that the NHAc substituents and the length of the oligosaccharide chain were both important for the binding of the oligosaccharide to SLL-2. The inhibition effect of the oligosaccharide relative to the morphological changes of Symbiodinium by SLL-2, was comparable to their binding affinity to SLL-2. In addition, we fortuitously found that the synthetic Forssman Antigen pentasaccharide directly promotes a morphological change in Symbiodinium. These results strongly indicate that the Forssman Antigen also functions as a chemical mediator of Symbiodinium.
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Synthesis and Biological Evaluation of the Forssman Antigen Pentasaccharide and Derivatives by a One‐Pot Glycosylation Procedure
Chemistry (Weinheim an der Bergstrasse Germany), 2013Co-Authors: Hiroshi Tanaka, Mitsuru Jimbo, Ryota Takeuchi, Nami Kuniya, Takashi TakahashiAbstract:The synthesis and biological evaluation of the Forssman Antigen pentasaccharide and derivatives thereof by using a one-pot glycosylation and polymer-assisted deprotection is described. The Forssman Antigen pentasaccharide, composed of GalNAcα(1,3)GalNAcβ(1,3)Galα(1,4)Galβ(1,4)Glc, was recently identified as a ligand of the lectin SLL-2 isolated from an octocoral Sinularia lochmodes. The chemo- and α-selective glycosylation of a thiogalactoside with a hemiacetal donor by using a mixture of Tf(2)O, TTBP and Ph(2)SO, followed by activation of the remaining thioglycoside, provided the trisaccharide at the reducing end in a one-pot procedure. The pentasaccharide was prepared by the α-selective glycosylation of the N-Troc-protected (Troc=2,2,2-trichloroethoxycarbonyl) thioglycoside with a 2-azide-1-hydroxyl glycosyl donor, followed by glycosidation of the resulting disaccharide at the C3 hydroxyl group of the trisaccharide acceptor in a one-pot process. We next applied the one-pot glycosylation method to the synthesis of pentasaccharides in which the galactosamine units were partially and fully replaced by galactose units. Among the three possible pentasaccharides, Galα(1,3)GalNAc and Galα(1,3)Gal derivatives were successfully prepared by the established method. An assay of the binding of the synthetic oligosaccharides to a fluorescent-labeled SLL-2 revealed that the NHAc substituents and the length of the oligosaccharide chain were both important for the binding of the oligosaccharide to SLL-2. The inhibition effect of the oligosaccharide relative to the morphological changes of Symbiodinium by SLL-2, was comparable to their binding affinity to SLL-2. In addition, we fortuitously found that the synthetic Forssman Antigen pentasaccharide directly promotes a morphological change in Symbiodinium. These results strongly indicate that the Forssman Antigen also functions as a chemical mediator of Symbiodinium.
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Possible involvement of glycolipids in lectin-mediated cellular transformation of symbiotic microalgae in corals
Journal of Experimental Marine Biology and Ecology, 2013Co-Authors: Mitsuru Jimbo, Ryuichi Sakai, Yuya Suda, Kazuhiko Koike, Sachiko Nakamura-tsuruta, Junko Kominami, Masugu Kamei, Jun Hirabayashi, Hisao KamiyaAbstract:We previously demonstrated that the lectin SLL-2, isolated from the octocoral Sinularia lochmodes, binds to the symbiotic microalgae Symbiodinium within the coral. Upon binding SLL-2, Symbiodinium cells transform from a flagellated swimming form into a non-flagellated coccoid form, the latter morphologically similar to the symbiotic stage found in corals. However, the site recognized by the lectin on the surface of Symbiodinium cells and the transformation mechanism have yet to be elucidated. We found that the ability of SLL-2 to induce the morphological change in Symbiodinium cells can be attenuated by pretreating the cells with glycosidases or by adding the SLL-2 binding inhibitor N-acetyl-d-galactosamine to the culture medium. These results suggest that d-galactose-containing glycoconjugates on the Symbiodinium cell surface are the key ligand through which SLL-2 induces morphological transformation. We also found that SLL-2 binds with high affinity to the Forssman Antigen, and masking the binding site on Symbiodinium cells by addition of anti-Forssman glycosphingolipid antibody inhibits the binding of SLL-2 to the cells. The antibody itself or other Forssman Antigen-binding proteins, such as Helix pomatia agglutinin, can transform Symbiodinium cells into the coccoid stage in the absence of SLL-2. A neutral lipid fraction prepared from cultured Symbiodinium cells reacted with the anti-Forssman glycosphingolipid antibody, supporting the hypothesis that a Forssman Antigen-like glycosphingolipid on the surface of Symbiodinium cells is involved in their morphological transformation induced by the lectin SLL-2.