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Qian X, Sujino K, Palcic MM, Ratcliffe RM. GLYCOSYLTRANSFERASES IN OLIGOSACCHARIDE SYNTHESIS. J Carbohydr Chem 2007. [DOI: 10.1081/car-120016492] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Abstract
Fucosylated carbohydrate structures are involved in a variety of biological and pathological processes in eukaryotic organisms including tissue development, angiogenesis, fertilization, cell adhesion, inflammation, and tumor metastasis. In contrast, fucosylation appears less common in prokaryotic organisms and has been suggested to be involved in molecular mimicry, adhesion, colonization, and modulating the host immune response. Fucosyltransferases (FucTs), present in both eukaryotic and prokaryotic organisms, are the enzymes responsible for the catalysis of fucose transfer from donor guanosine-diphosphate fucose to various acceptor molecules including oligosaccharides, glycoproteins, and glycolipids. To date, several subfamilies of mammalian FucTs have been well characterized; these enzymes are therefore delineated and used as models. Non-mammalian FucTs that possess different domain construction or display distinctive acceptor substrate specificity are highlighted. It is noteworthy that the glycoconjugates from plants and schistosomes contain some unusual fucose linkages, suggesting the presence of novel FucT subfamilies as yet to be characterized. Despite the very low sequence homology, striking functional similarity is exhibited between mammalian and Helicobacter pylori alpha1,3/4 FucTs, implying that these enzymes likely share a conserved mechanistic and structural basis for fucose transfer; such conserved functional features might also exist when comparing other FucT subfamilies from different origins. Fucosyltranferases are promising tools used in synthesis of fucosylated oligosaccharides and glycoconjugates, which show great potential in the treatment of infectious and inflammatory diseases and tumor metastasis.
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Affiliation(s)
- Bing Ma
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada T6G 2H7
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Ma B, Audette GF, Lin S, Palcic MM, Hazes B, Taylor DE. Purification, Kinetic Characterization, and Mapping of the Minimal Catalytic Domain and the Key Polar Groups of Helicobacter pylori α-(1,3/1,4)-Fucosyltransferases. J Biol Chem 2006; 281:6385-94. [PMID: 16407247 DOI: 10.1074/jbc.m511320200] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The minimal catalytic domain of alpha-(1,3/1,4)-fucosyltransferases (FucTs) from Helicobacter pylori strains NCTC11639 and UA948 was mapped by N- and C-terminal truncations. Only the C terminus could be truncated without significant loss of activity. 11639FucT and UA948FucT contain 10 and 8 heptad repeats, respectively, which connect the catalytic domain with the C-terminal putative amphipathic alpha-helices. Deletion of all heptad repeats almost completely abolished enzyme activity. Nevertheless, with only one heptad repeat 11639FucT is fully active, whereas UA948FucT is partially active. Removal of the two putative amphipathic alpha-helices dramatically increased protein expression and solubility, enabling purification with yields of milligrams/liter. Steady-state kinetic analysis of the purified FucTs showed that 11639FucTs possessed slightly tighter binding affinity for both Type II acceptor and GDP-fucose donor than UA948FucT, and its kcat of 2.3 s(-1) was double that of UA948FucT, which had a kcat value of 1.1 s(-1) for both Type II and Type I acceptors. UA948FucT strongly favors Type II over the Type I acceptor with a 20-fold difference in acceptor Km. Sixteen modified Type I and Type II series acceptors were employed to map the molecular determinants of acceptors required for recognition by H. pylori alpha-(1,3/1,4)-FucTs. Deoxygenation at 6-C of the galactose in Type II acceptor caused a 5000-fold decrease in alpha1,3 activity, whereas in Type I acceptor this completely abolished alpha1,4 activity, indicating that this hydroxyl group is a key polar group.
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Affiliation(s)
- Bing Ma
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta T6G 2H7
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Ma B, Lau LH, Palcic MM, Hazes B, Taylor DE. A single aromatic amino acid at the carboxyl terminus of Helicobacter pylori {alpha}1,3/4 fucosyltransferase determines substrate specificity. J Biol Chem 2005; 280:36848-56. [PMID: 16150700 DOI: 10.1074/jbc.m504415200] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Fucosyltransferases (FucT) from different Helicobacter pylori strains display distinct Type I (Galbeta1,3GlcNAc) or Type II (Galbeta1,4GlcNAc) substrate specificity. FucT from strain UA948 can transfer fucose to the OH-3 of Type II acceptors as well as to the OH-4 of Type I acceptors on the GlcNAc moiety, so it has both alpha1,3 and alpha1,4 activities. In contrast, FucT from strain NCTC11639 has exclusive alpha1,3 activity. Our domain swapping study (Ma, B., Wang, G., Palcic, M. M., Hazes, B., and Taylor, D. E. (2003) J. Biol. Chem. 278, 21893-21900) demonstrated that exchange of the hypervariable loops, (347)DNPFIFC(353) in 11639FucT and (345)CNDAHYSALH(354) in UA948FucT, were sufficient to either confer or abolish alpha1,4 activity. Here we performed alanine scanning site-directed mutagenesis to identify which amino acids within (345)CNDAHYSALH(354) of UA948FucT confer Type I substrate specificity. The Tyr(350) --> Ala mutation dramatically reduced alpha1,4 activity without lowering alpha1,3 activity. None of the other alanine substitutions selectively eliminated alpha1,4 activity. To elucidate how Tyr(350) determines alpha1,4 specificity, mutants Tyr(350) --> Phe, Tyr(350) --> Trp, and Tyr(350) --> Gly were constructed in UA948FucT. These mutations did not decrease alpha1,3 activity but reduced the alpha1,4 activity to 66.9, 55.6, and 3.1% [corrected] of wild type level, respectively. Apparently the aromatic nature, but not the hydroxyl group of Tyr(350), is essential for alpha1,4 activity. Our data demonstrate that a single amino acid (Tyr(350)) in the C-terminal hypervariable region of UA948FucT determines Type I acceptor specificity. Notably, a single aromatic residue (Trp) has also been implicated in controlling Type I acceptor preference for human FucT III, but it is located in an N-terminal hypervariable stem domain.
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Affiliation(s)
- Bing Ma
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta T6G 2H7, Canada
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5
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Galan MC, Dodson CS, Venot AP, Boons GJ. Glycosyltransferase activity can be selectively modulated by chemical modifications of acceptor substrates. Bioorg Med Chem Lett 2004; 14:2205-8. [PMID: 15081009 DOI: 10.1016/j.bmcl.2004.02.024] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2003] [Revised: 02/04/2004] [Accepted: 02/05/2004] [Indexed: 11/15/2022]
Abstract
A range of N-acetyllactosamine derivatives, which are modified by a wide range of functionalities at C-2(') and C-6, have been synthesised and the kinetic parameters of transfer catalysed by recombinant alpha-2,6-sialyltransferase and alpha-1,3-fucoyltransferase VI determined. Several of the chemical modifications led to selective modulate the activity the enzymes and offer promising lead compounds for the development of oligosaccharide primers for selective metabolic inhibition of oligosaccharide biosynthesis.
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Affiliation(s)
- M Carmen Galan
- Complex Carbohydrate Research Center, University of Georgia, 220 Riverbend Road, Athens, GA 30602, USA
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Galan MC, Venot AP, Boons GJ. Glycosyltransferase activity can be modulated by small conformational changes of acceptor substrates. Biochemistry 2003; 42:8522-9. [PMID: 12859199 DOI: 10.1021/bi034189d] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A range of N-acetyllactosamine derivatives (compounds 4-7) that have restricted mobilities around their glycosidic linkages have been employed to determine how small changes in conformational properties of an oligosaccharide acceptor affect catalytic efficiencies of glycosylations by alpha-2,6- and alpha-2,3-sialyltransferases and alpha-1,3-fucosyltransferases IV and VI. Restriction of conformational mobility was achieved by introducing tethers of different length and chemical composition between the C-6 and C-2' hydroxyl of LacNAc. Compound 4 is a 2',6-anhydro derivative which is highly constrained and can adopt only two unusual conformations at the LacNAc glycosidic linkage. Compound 5 is modified by a methylene acetal tether and can exist in a larger range of conformations; however, the Phi dihedral angle is restricted to values smaller than 30 degrees, which are not entirely similar to minimum energy conformations of LacNAc. The ethylene-tethered 6 can attain conformations in the relatively large energy plateau of LacNAc that include syn conformations A and B, whereas compound 7, which is modified by a methylamide tether, can only reside in the B-conformer. 2',6-Dimethoxy derivative 2 was employed to determine the effect of alkylation of the C-6 and C-2' hydroxyls of 5 and 6 whereas 3 was used to reveal the effects of the C-6 amide and C-2' alkylation of 7. The apparent kinetic parameters of transfer to the conformationally constrained 4-7 and reference compounds 1-3 catalyzed by alpha-2,6- and alpha-2,3-sialyltransferases and alpha-1,3-fucosyltransferases IV and VI were determined, and the results correlated with their conformational properties. The data for 4-6 showed that each enzyme recognizes N-acetyllactosamine in a low minimum energy conformation. A small change in conformational properties such as in compound 5 resulted in a significant loss of catalytic activity. Larger conformational changes such as in compound 4 abolished all activity of the sialyltransferases whereas the fucosyltransferases showed some activity, albeit very low. The kinetic data for compounds 4 and 5 demonstrate clearly that different glycosyltransferases respond differently to conformational changes, and the fucosyltransferases lost less activity than the sialyltransferases. Correlating apparent kinetic parameters of conformationally constrained 6 and 7 and their reference compounds 2 and 3 further supports the fact that different enzymes respond differently and indicates that sialyltransferases and fucosyltransferases recognize N-acetyllactosamine in a different conformation. Collectively, the data presented here indicate that small conformational changes of an oligosaccharide acceptor induced by, for example, the protein structure can be employed to modulate the patterns of protein glycosylation.
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Affiliation(s)
- M Carmen Galan
- Complex Carbohydrate Research Center, University of Georgia, 220 Riverbend Road, Athens, Georgia 30602, USA
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Ma B, Wang G, Palcic MM, Hazes B, Taylor DE. C-terminal amino acids of Helicobacter pylori alpha1,3/4 fucosyltransferases determine type I and type II transfer. J Biol Chem 2003; 278:21893-900. [PMID: 12676935 DOI: 10.1074/jbc.m301704200] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The alpha1,3/4 fucosyltransferase (FucT) enzyme from Helicobacter pylori catalyzes fucose transfer from donor GDP-beta-l-fucose to the GlcNAc group of two series of acceptor substrates in H. pylori lipopolysaccharide: betaGal1,3betaGlcNAc (Type I) or betaGal1,4betaGlcNAc (Type II). Fucose is added either in alpha1,3 linkage of Type II acceptor to produce Lewis X or in alpha1,4 linkage of Type I acceptor to produce Lewis A, respectively. H. pylori FucTs from different strains have distinct Type I or Type II substrate specificities. FucT in H. pylori strain NCTC11639 has an exclusive alpha1,3 activity because it recognizes only Type II substrates, whereas FucT in H. pylori strain UA948 can utilize both Type II and Type I acceptors; thus it has both alpha1,3 and alpha1,4 activity, respectively. To identify elements conferring substrate specificity, 12 chimeric FucTs were constructed by domain swapping between 11639FucT and UA948FucT and characterized for their ability to transfer fucose to Type I and Type II acceptors. Our results indicate that the C-terminal region of H. pylori FucTs controls Type I and Type II acceptor specificity. In particular, the highly divergent C-terminal portion, seven amino acids DNPFIFC at positions 347-353 in 11639FucT, and the corresponding 10 amino acids CNDAHYSALH at positions 345-354 in UA948FucT, controls the Type I and Type II acceptor recognition. This is the opposite of mammalian FucTs where acceptor preference is determined primarily by the N-terminal residues in the hypervariable stem domain.
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Affiliation(s)
- Bing Ma
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta T6G 2H7, Canada
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Ogawa S, Matsunaga N, Li H, Palcic MM. Synthesis of Ether- and Imino-Linked OctylN-Acetyl-5a′-carba-β-lactosaminides and -isolactosaminides: Acceptor Substrates for α-(1→3/4)-Fucosyltransferase, and Enzymatic Synthesis of 5a′-Carbatrisaccharides. European J Org Chem 1999. [DOI: 10.1002/(sici)1099-0690(199903)1999:3<631::aid-ejoc631>3.0.co;2-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Shinoda K, Tanahashi E, Fukunaga K, Ishida H, Kiso M. Detailed acceptor specificities of human alpha1,3-fucosyltransferases, Fuc-TVII and Fuc-TVI. Glycoconj J 1998; 15:969-74. [PMID: 10211702 DOI: 10.1023/a:1006933808303] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
To clarify the acceptor specificity of Fuc-TVII, its activity toward various analogs of a 2-(trimethylsilyl)ethyl alpha2,3-sialyl lacto-N-neotetraose, an acceptor for both Fuc-TVII and Fuc-TVI, was examined in comparison with that of Fuc-TVI. Fuc-TVII required three portions of alpha2,3-sialylated type-2 oligosaccharide structures (i.e., the hydroxyl group at C-4 of Gal, the hydroxyl group at C-3 of GlcNAc, and the carbonylamino group at C-2 of GlcNAc) for its acceptor recognition. Fuc-TVI required the carbonylamino group at C-2 of GlcNAc for its acceptor recognition. Fuc-TVII showed higher affinity toward two analogs, in which the hydroxyl group at C-6 of GlcNAc has been deoxygenated and the acetamide group of N-acetylneuraminic acid has been replaced with a glycolylamino group, respectively, than that toward the original compound. On the other hand, Fuc-TVI showed higher affinity toward an analog, in which the acetamide group of GlcNAc has been modified with a lauroylamino group, than that toward the original compound. Analysis involving mass spectrometry confirmed that both Fuc-TVII and Fuc-TVI could fucosylate these three analogs to yield sialyl Lewis x derivatives.
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Affiliation(s)
- K Shinoda
- Tokyo Research Laboratories, Kyowa Hakko Kogyo Co., Ltd., Tokyo, Japan.
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Qian X, Hindsgaul O, Li H, Palcic MM. Unexpected Enzymatic Fucosylation of the Hindered Tertiary Alcohol of 3-C-Methyl-N-Acetyllactosamine Produces a Novel Analogue of the LeX-Trisaccharide. J Am Chem Soc 1998. [DOI: 10.1021/ja973361w] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Xiangping Qian
- Department of Chemistry, University of Alberta Edmonton, Alberta T6G 2G2, Canada
| | - Ole Hindsgaul
- Department of Chemistry, University of Alberta Edmonton, Alberta T6G 2G2, Canada
| | - Hong Li
- Department of Chemistry, University of Alberta Edmonton, Alberta T6G 2G2, Canada
| | - Monica M. Palcic
- Department of Chemistry, University of Alberta Edmonton, Alberta T6G 2G2, Canada
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11
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Palcic MM, Li H, Zanini D, Bhella RS, Roy R. Chemoenzymatic synthesis of dendritic sialyl Lewis(x). Carbohydr Res 1997; 305:433-42. [PMID: 9648262 DOI: 10.1016/s0008-6215(97)00263-2] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Traditional structure activity relationship studies (SAR) have led to the development of numerous sialyl Lewis(x) analogs in the search for potential antiinflammatory agents. However, these methods do not take into account cluster or multivalent effects. Reported herein is the chemoenzymatic synthesis of di-, tetra-, and octa-valent sLe(x) ligands scaffolded on dendrimers. Hypervalent L-lysine cores with covalently attached 2-acetamido-2-deoxy-D-glucose (N-acetylglucosamine, GlcNAc) residues were chemically prepared and enzymatically transformed into sLe(x) containing dendrimers so that multivalency, and its role in selectin-sLe(x) interactions may be evaluated. This work constitutes another successful enzymatic synthesis of sLe(x) and represents the first example of GlcNAc elongation on a synthetic dendrimer scaffold. These sLe(x) dendrimers are currently being investigated as selectin antagonists.
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Affiliation(s)
- M M Palcic
- Department of Chemistry, University of Alberta, Edmonton, Canada
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12
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Affiliation(s)
- C Augé
- Laboratoire de Chimie Organique Multifonctionnelle, Université de Paris-Sud, Orsay, France
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Costache M, Apoil PA, Cailleau A, Elmgren A, Larson G, Henry S, Blancher A, Iordachescu D, Oriol R, Mollicone R. Evolution of fucosyltransferase genes in vertebrates. J Biol Chem 1997; 272:29721-8. [PMID: 9368041 DOI: 10.1074/jbc.272.47.29721] [Citation(s) in RCA: 91] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Cloning and expression of chimpanzee FUT3, FUT5, and FUT6 genes confirmed the hypothesis that the gene duplications at the origin of the present human cluster of genes occurred between: (i) the great mammalian radiation 80 million years ago and (ii) the separation of man and chimpanzee 10 million years ago. The phylogeny of fucosyltransferase genes was completed by the addition of the FUT8 family of alpha(1,6)fucosyltransferase genes, which are the oldest genes of the fucosyltransferase family. By analysis of data banks, a new FUT8 alternative splice expressed in human retina was identified, which allowed mapping the human FUT8 gene to 14q23. The results suggest that the fucosyltransferase genes have evolved by successive duplications, followed by translocations, and divergent evolution from a single ancestral gene.
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Affiliation(s)
- M Costache
- INSERM U178, Université de Paris Sud (XI), 94807 Villejuif Cedex, France
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Abstract
Significant progress has recently been achieved in the use of glycosidases and glycosyltransferases as synthetic tools. Glycosidases have been used to synthesize trisaccharides with a reasonable overall yield, as well as high-mannose neoglycoconjugates. Studies on glycosyltransferases have defined reaction mechanisms and demonstrated reasonable substrate tolerance of these enzymes. Effective methodology for the synthesis of defined glycoproteins has also been demonstrated.
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Affiliation(s)
- G M Watt
- Edinburgh Centre for Protein Technology, Department of Chemistry, University of Edinburgh, UK
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