Further characterization of the combining sites of Bandeiraea (Griffonia) simplicifolia lectin-I, isolectin A(4).
Bandeiraea (Griffonia) simplicifolia lectin-I, isolectin A(4)(GS I-A(4)), which is cytotoxic to the human colon cancer cell lines, is one of two lectin families derived from its seed extract. It contains only a homo-oligomer of subunit A, and is most specific for GalNAcalpha1-->. In order to elucidate the GS I-A(4)-glycoconjugate interactions in greater detail, the combining site of this lectin was further characterized by enzyme linked lectino-sorbent assay (ELLSA) and by inhibition of lectin-glycoprotein interactions. This study has demonstrated that the Tn-containing glycoproteins tested, consisting of mammalian salivary glycoproteins (armadillo, asialo-hamster sublingual, asialo-ovine, -bovine, and -porcine submandibular), are bound strongly by GS I-A(4.)Among monovalent inhibitors so far tested, p-NO2-phenylalphaGalNAc is the most potent, suggesting that hydrophobic forces are important in the interaction of this lectin. GS I-A(4)is able to accommodate the monosaccharide GalNAc at the nonreducing end of oligosaccharides. This suggests that the combining site of the lectin is a shallow cavity. Among oligosaccharides and monosaccharides tested as inhibitors of the binding of GS I-A(4), the hierarchy of potencies are: GalNAcalpha1-->3GalNAcbeta1-->3Galalpha1-->4Galbeta 1-->4Glc (Forssman pentasaccharide) > GalNAcalpha1-->3(LFucalpha1-->2)Gal (blood group A)()> GalNAc > Galalpha1-->4Gal > Galalpha1-->3Gal (blood group B-like)> Gal.
Wu
A M
AM
Glyco-Immunochemistry Research Lab, Institute of Molecular and Cellular Biology, Chang-Gung University, Taiwan.
Wu
J H
JH
Chen
Y Y
YY
Song
S C
SC
Kabat
E A
EA
D000818:Animals; D001135:Armadillos; D001789:Blood Group Antigens / Q000378:metabolism; D002240:Carbohydrate Sequence; D006224:Cricetinae; D004443:Echinococcosis / Q000378:metabolism / Q000662:veterinary; D005260:Female; D006023:Glycoproteins / Q000378:metabolism*; D006801:Humans; D037102:Lectins / Q000737:chemistry*; D008024:Ligands; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000378:metabolism; D010048:Ovarian Cysts / Q000378:metabolism; D037121:Plant Lectins; D011485:Protein Binding; D012471:Salivary Proteins and Peptides / Q000378:metabolism; D012756:Sheep; D012757:Sheep Diseases / Q000378:metabolism; D013552:Swine
D001789:Blood Group Antigens; D006023:Glycoproteins; C045475:Griffonia simplicifolia lectins; D037102:Lectins; D008024:Ligands; D009844:Oligosaccharides; D037121:Plant Lectins; D012471:Salivary Proteins and Peptides