Reaction participants Show >> << Hide
- Name help_outline a globoside Gb4Cer Identifier CHEBI:88167 Charge 0 Formula C30H50N2O23R2 SMILEShelp_outline [C@H]([C@@H](*)O)(NC(=O)*)CO[C@@H]1O[C@@H]([C@@H](O[C@@H]2O[C@@H]([C@H](O[C@@H]3[C@@H]([C@@H](O[C@H]4[C@@H]([C@H]([C@@H](O)[C@H](O4)CO)O)NC(C)=O)[C@H]([C@@H](CO)O3)O)O)[C@@H]([C@H]2O)O)CO)[C@@H]([C@H]1O)O)CO 2D coordinates Mol file for the small molecule Search links Involved in 10 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline UDP-α-D-galactose Identifier CHEBI:66914 Charge -2 Formula C15H22N2O17P2 InChIKeyhelp_outline HSCJRCZFDFQWRP-ABVWGUQPSA-L SMILEShelp_outline OC[C@H]1O[C@H](OP([O-])(=O)OP([O-])(=O)OC[C@H]2O[C@H]([C@H](O)[C@@H]2O)n2ccc(=O)[nH]c2=O)[C@H](O)[C@@H](O)[C@H]1O 2D coordinates Mol file for the small molecule Search links Involved in 151 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline a globoside NOR1 Identifier CHEBI:140614 Charge 0 Formula C36H60N2O28R2 SMILEShelp_outline [C@H]([C@@H](*)O)(NC(=O)*)CO[C@@H]1O[C@@H]([C@@H](O[C@@H]2O[C@@H]([C@H](O[C@@H]3[C@@H]([C@@H](O[C@H]4[C@@H]([C@H]([C@@H](O[C@@H]5[C@@H]([C@@H](O)[C@H]([C@@H](CO)O5)O)O)[C@H](O4)CO)O)NC(C)=O)[C@H]([C@@H](CO)O3)O)O)[C@@H]([C@H]2O)O)CO)[C@@H]([C@H]1O)O)CO 2D coordinates Mol file for the small molecule Search links Involved in 4 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline UDP Identifier CHEBI:58223 Charge -3 Formula C9H11N2O12P2 InChIKeyhelp_outline XCCTYIAWTASOJW-XVFCMESISA-K SMILEShelp_outline O[C@@H]1[C@@H](COP([O-])(=O)OP([O-])([O-])=O)O[C@H]([C@@H]1O)n1ccc(=O)[nH]c1=O 2D coordinates Mol file for the small molecule Search links Involved in 711 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
- Name help_outline H+ Identifier CHEBI:15378 Charge 1 Formula H InChIKeyhelp_outline GPRLSGONYQIRFK-UHFFFAOYSA-N SMILEShelp_outline [H+] 2D coordinates Mol file for the small molecule Search links Involved in 10,232 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
Cross-references
| RHEA:56184 | RHEA:56185 | RHEA:56186 | RHEA:56187 | |
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| Reaction direction help_outline | undefined | left-to-right | right-to-left | bidirectional |
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Related reactions help_outline
Specific form(s) of this reaction
Publications
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Human Gb3/CD77 synthase reveals specificity toward two or four different acceptors depending on amino acid at position 211, creating P(k), P1 and NOR blood group antigens.
Kaczmarek R., Duk M., Szymczak K., Korchagina E., Tyborowska J., Mikolajczyk K., Bovin N., Szewczyk B., Jaskiewicz E., Czerwinski M.
Human Gb3/CD77 synthase (α1,4-galactosyltransferase, P(k) synthase), encoded by A4GALT gene, is known for synthesis of Gal(α1-4)Gal moiety in globotriaosylceramide (Gb3Cer, CD77, P(k) blood group antigen), a glycosphingolipid of the globo series. Recently, it was shown that c.631C > G mutation in ... >> More
Human Gb3/CD77 synthase (α1,4-galactosyltransferase, P(k) synthase), encoded by A4GALT gene, is known for synthesis of Gal(α1-4)Gal moiety in globotriaosylceramide (Gb3Cer, CD77, P(k) blood group antigen), a glycosphingolipid of the globo series. Recently, it was shown that c.631C > G mutation in A4GALT, which causes p.Q211E substitution in the open reading frame of the enzyme, broadens the enzyme specificity, making it able also to synthesize Gal(α1-4)GalNAc moiety, which constitutes the defining terminal disaccharide of the NOR antigen (carried by two glycosphingolipids: NOR1 and NOR2). Terminal Gal(α1-4)Gal disaccharide is also present in another glycosphingolipid blood group antigen, called P1, which together with P(k) and NOR comprises the P1PK blood group system. Despite several attempts, it was never clearly shown that P1 antigen is synthesized by Gb3/CD77 synthase, leaving open an alternative hypothesis that there are two homologous α1,4-galactosyltransferases in humans. In this study, using recombinant Gb3/CD77 synthase produced in insect cells, we show that the consensus enzyme synthesizes both the P(k) and P1 antigens, while its p.Q211E variant additionally synthesizes the NOR antigen. This is the first direct biochemical evidence that Gb3/CD77 synthase is able to synthesize two different glycosphingolipid antigens: P(k) and P1, and when p.Q211E substitution is present, the NOR antigen is also synthesized. << Less
Biochem. Biophys. Res. Commun. 470:168-174(2016) [PubMed] [EuropePMC]
This publication is cited by 2 other entries.
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Evaluation of an amino acid residue critical for the specificity and activity of human Gb3/CD77 synthase.
Kaczmarek R., Mikolajewicz K., Szymczak K., Duk M., Majorczyk E., Krop-Watorek A., Buczkowska A., Czerwinski M.
Human Gb3/CD77 synthase (α1,4-galactosyltransferase) is the only known glycosyltransferase that changes acceptor specificity because of a point mutation. The enzyme, encoded by A4GALT locus, is responsible for biosynthesis of Gal(α1-4)Gal moiety in Gb3 (CD77, P<sup>k</sup> antigen) and P1 glycosph ... >> More
Human Gb3/CD77 synthase (α1,4-galactosyltransferase) is the only known glycosyltransferase that changes acceptor specificity because of a point mutation. The enzyme, encoded by A4GALT locus, is responsible for biosynthesis of Gal(α1-4)Gal moiety in Gb3 (CD77, P<sup>k</sup> antigen) and P1 glycosphingolipids. We showed before that a single nucleotide substitution c.631C > G in the open reading frame of A4GALT, resulting in replacement of glutamine with glutamic acid at position 211 (substitution p. Q211E), broadens the enzyme acceptor specificity, so it can not only attach galactose to another galactose but also to N-acetylgalactosamine. The latter reaction leads to synthesis of NOR antigens, which are glycosphingolipids with terminal Gal(α1-4)GalNAc sequence, never before described in mammals. Because of the apparent importance of position 211 for enzyme activity, we stably transfected the 2102Ep cells with vectors encoding Gb3/CD77 synthase with glutamine substituted by aspartic acid or asparagine, and evaluated the cells by quantitative flow cytometry, high-performance thin-layer chromatography and real-time PCR. We found that cells transfected with vectors encoding Gb3/CD77 synthase with substitutions p. Q211D or p. Q211N did not express P<sup>k</sup>, P1 and NOR antigens, suggesting complete loss of enzymatic activity. Thus, amino acid residue at position 211 of Gb3/CD77 synthase is critical for specificity and activity of the enzyme involved in formation of P<sup>k</sup>, P1 and NOR antigens. Altogether, this approach affords a new insight into the mechanism of action of the human Gb3/CD77 synthase. << Less
Glycoconj J 33:963-973(2016) [PubMed] [EuropePMC]
This publication is cited by 2 other entries.