• Nobuyuki Kurosawa
  • Shuichi Tsuji


ST6GalNAc-I is a CMP-sialic acid: N-acetylgalactosaminide α2-6-sialyltransferase (GalNAc α2-6-sialyltransferase), and a member of the ST6GalNAc subfamily that exhibits activity toward GalNAc-O-Ser/Thr, Galβ1-3GalNAc-O-Ser/Thr, and NeuAcα2- 3Galβ1-3GalNAc-O-Ser/Thr (Kurosawa et al. 1994, 2000; Ikehara et al. 1999; Kono et al. 2000). Like other sialyltransferases, ST6GalNAc-I exhibits type II membrane protein topology and has characteristic motifs for sialyltransferases called sialylmotifs L, S, and VS. ST6GalNAc-I also has the Kurosawa motif (Cys-Xaa75-in82-Cys-Xaa-Cys- Ala-Xaa-Va1-Xaa150-160-Cys; Xaa denotes any amino acid residue) as seen in the ST3Gal family and two members of the ST6GalNAc family (Kurosawa et al. 1996; Tsuji 1999). ST6GalNAc-I is a relatively large sialyltransferase (600 amino acids in length in Homo sapiens, 526 in Mus musculus, and 566 in Gallus gallus) compared with other sialyltransferases characterized to date. This structural character is attributed to its long stem domain. The putative active domain of mouse ST6GalNAc-I (250 amino acid residues from the C-terminal end) showed a high identity to the corresponding region of human ST6GalNAc-I (85%) and to the chick enzyme (67%), but showed low identity to other members of the mouse ST6GalNAc family: ST6GalNAc-II 48%, ST6GalNAc-III 41%, ST6GalNAc-IV 23%, and ST6GalNAc-V 16%. Human ST6GalNAc-I cDNA has two isoforms (2.46 and 2.23 kb). The former encodes an active enzyme with a predicted 600 amino acid sequence. The latter, a splice-variant of the long form, encodes an inactive enzyme (Ikehara et al. 1999).


Gallus Gallus Human Colorectal Cancer Cell Fusion Enzyme Human Colorectal Cancer Cell Line Maxillary Gland 
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  1. Ikehara Y, Naoya Kojima N, Kurosawa N, Kudo T, Nishihara S, Morozumi K, Kono M, Tsuji S, Narimatsu H (1999) Cloning and expression of a human gene encoding an N-acetylgalactosamine-α2,6-sialyltransferase (ST6GalNAc-I) which is a candidate for synthesis of cancer-associated sialyl-Tn. Glycobiology 9:1213–1224PubMedCrossRefGoogle Scholar
  2. Kono M, Yoshida Y, Kojima N, Tsuji S (1996) Molecular cloning and expression of a fifth-type of α2,8-sialyltransferase (ST8Sia V): its substrate specificity is similar to that of SN-V/III, which synthesize GD1c, GT1a, GQ1b and GT3. J Biol Chem 271:29366–29371PubMedCrossRefGoogle Scholar
  3. Kono M, Tsuda T, Ogata S, Takashima S, Liu H, Hamamoto T, Itzkowitz SH, Nishimura S, Tsuji S (2000) Re-defined substrate specificity of ST6GalNAc-II: a second candidate sialyl-Tn synthase. Biochem Biophys Res Commun 272:94–97PubMedCrossRefGoogle Scholar
  4. Kurosawa N, Hamamoto T, Lee Y-C, Nakaoka T, Kojima N, Tsuji S (1994) Molecular cloning and expression of GalNAc α2,6-sialyltransferase. J Biol Chem 269:1402–1409PubMedGoogle Scholar
  5. Kurosawa N, Inoue M, Yoshida Y, Tsuji S (1996) Molecular cloning and genomic analysis of mouse Galβ1,3GalNAc-specific GalNAc α2,6-sialyltransferase. J Biol Chem 271:15109–15116PubMedCrossRefGoogle Scholar
  6. Kurosawa N, Takashima S, Kono M, Ikehara Y, Inoue M, Tachida Y, Narimatsu H, Tsuji S (2000) Molecular cloning and genomic analysis of mouse GalNAc α2,6-sialyltransferase (ST6GalNAc-I). J Biochem 127:845–854PubMedCrossRefGoogle Scholar
  7. Niwa H, Yamamura K, Miyazaki J (1991) Efficient selection for high-expression transfectants with a novel eukaryotic vector. Gene 108:193–199PubMedCrossRefGoogle Scholar
  8. Sadler JE, Rearick JI, Hill RL (1979) Purification to homogeneity and enzymatic characterization of an α-N-acetylgalactosaminide α2-6 sialyltransferase from porcine submaxillary glands. J Biol Chem 254:5934–5941PubMedGoogle Scholar
  9. Tsuda T, Nishimura S (1996) Synthesis of an antifreeze glycoprotein analogue: efficient preparation of sequential glycopeptide polymers. Chem Commun 2779-2780Google Scholar
  10. Tsuji S (1999) Molecular cloning and characterization of sialyltransferases. In: Inoue Y, Lee YC, Troy FA (eds) Sialobiology and other novel forms of glycosylation. Gakushin, Osaka, pp 145–154Google Scholar
  11. Tsuji S, Datta AK, Paulson JC (1996) Systematic nomenclature for sialyltransferases. Glycobiology 6(7):v–viiPubMedCrossRefGoogle Scholar

Copyright information

© Springer Japan 2002

Authors and Affiliations

  • Nobuyuki Kurosawa
    • 1
  • Shuichi Tsuji
    • 2
  1. 1.Department of Materials and Biosystem Engineering, Faculty of EngineeringToyama UniversityToyamaJapan
  2. 2.Department of ChemistryOchanomizu University, Otsuka, Bunkyo-kuTokyoJapan

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