Fraction A of armadillo submandibular glycoprotein and its desialylated product as sialyl‐Tn and Tn receptors for lectins

FEBS Letters

Wu, Albert M³  Herp, Anthony³  Song, Shuh-Chyung³  Wu, June H¹  Shen, F-shiun² 

[1] Department of Microbiology and Immunology, Chang-Gung Medical College, Kwei-san, Tao-yuan, 333, Taiwan;Graduate Institute of Medical Technology, College of Medicine, National Taiwan University, Taipei, Taiwan;Glyco-Immunochemistry Research Laboratory, Institute of Molecular and Cellular Biology, Chang-Gung Medical College, Kwei-san, Tao-yuan, 333, Taiwan

关键词: Lectin reactivity;    Armadillo submandibular glycoprotein;    Gal;    d-galactopyranose;    Glc;    d-glucopyranose;    lFuc or Fuc;    l-fucopyranose;    GalNAc;    2-acetamido-2-deoxy-d-galactopyranose;    GlcNAc;    2-acetamido-2-deoxy-d-glucopyranose;    NeuAc;    N-acetylneuraminic acid. Abbreviations of lectins and lectin determinants are given in Table 1. ASG-A;    armadillo submandibular glycoprotein;    fraction A [9] one of the sialic acid containing glycoproteins in armadillo submandibular glands (see text);    ASG-Tn;    the desialylated ASG-A;    HSM;    hamster submaxillary glycoproteins;    the carbohydrate side chains of HSM were mainly of sialyl-Tn sequence;    HSM-Tn;    the desialylated HSM containing only Tn (GalNAcαl→Ser/Thr) residues as carbohydrate side chains [21];   

DOI  :  10.1016/0014-5793(95)00106-J

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Fraction A of the armadillo submandibular glycoprotein (ASG-A) is one of the simplest glycoproteins among mammalian salivary mucins. The carbohydrate side chains of this mucous glycoprotein have one-third of the NeuAcα2→6GalNAc (sialyl-Tn) sequence and two thirds of Tn (GalNAcα→Ser/Thr) residues. Those of the desialylated product (ASG-Tn) are almost exclusively unsubstituted GalNAc residues (Tn determinant). When the binding properties of these glycoproteins were tested by a precipitin assay with Gal, GalNAc and GlcNAc specific lectins, it was found that ASG-Tn reacted strongly with all of the Tn-active lectins and completely precipitated Vicia villosa (VVL both B₄ and mixture of A and B), Maclura pomifera (MPA), and Artocarpus integrifolia (jacalin) lectins. However, it precipitated poorly or negligibly with Ricinus communis (RCA₁); Dolichos biflorus (DBA); Viscum album, ML-1; Arachis hypogaea (PNA), and Triticum vulgaris (WGA). The reactivity of ASG-A (sialyl-Tn) was as active as that of ASG-Tn with MPA and less or slightly less active than that of ASG-Tn with VVL-A+B, VVLB₄, HPA, WFA, and jacalin, as one-third of its Tn was sialylated. These findings indicate that ASG-A and its desialylated product (ASG-Tn) are highly useful reagents for the differentiation of Tn, T (Galβ1→3GalNAc), A (GalNAcα1→3Gal) or Gal specific lectins and monoclonal antibodies against such epitopes.

【 授权许可】

Unknown