Multi-antennary Gal beta1-->4GlcNAc and Gal beta1-->3GalNAc clusters as important ligands for a lectin isolated from the sponge Geodia cydonium.
The affinity of a lectin from the sponge Geodia cydonium (GCL-I) for multi-antennary Gal beta1-->4GlcNAc and Gal beta1-->3GalNAc ligands was studied by both the biotin/avidin-based microtiter plate lectin binding assay and the inhibition of lectin-glycoform interaction. Among the glycoforms tested for binding, GCL-I reacted strongly with three multi-antennary Gal beta1-->4GlcNAc clusters containing glycoproteins (asialo human and bovine alpha1-acid gps and asialo fetuin), T (Gal beta1-->3GalNAc) rich glycoprotein from porcine salivary gland, asialo bird nest gp, and human blood group A active cyst gp, while human and bovine alpha1-acid gps, fetuin, and Tn containing gps were inactive. Among the haptens tested for inhibition, tri-antennary Gal beta1-->4GlcNAc (Tri-II) was about 1500, 72, and 72 times more active than GalNAc, Gal beta1-->4GlcNAc (II), and Gal beta1-->3GalNAc (T), respectively. Based on the present and previous results, it is proposed that tri-antennary Gal beta1-->4GlcNAc and Gal beta1-->3GalNAc clusters, in addition to GalNAc alpha1-->3GalNAc and GalNAc alpha1-->3Gal, are also important ligands for binding; and sialic acid of glycoprotein does interfere with binding.
Wu
J H
JH
Glyco-Immunochemistry Research Laboratory, Institute of Molecular and Cellular Biology, Chang-Gung Medical College, Tao-yuan, Taiwan.
Song
S C
SC
Chen
Y Y
YY
Tsai
M C
MC
Kabat
E A
EA
Wu
A M
AM
D000818:Animals; D002417:Cattle; D004187:Disaccharides / Q000378:metabolism; D006801:Humans; D037102:Lectins / Q000302:isolation & purification / Q000378:metabolism*; D008024:Ligands; D011161:Porifera / Q000378:metabolism*; D014312:Trisaccharides / Q000378:metabolism
D004187:Disaccharides; D037102:Lectins; D008024:Ligands; D014312:Trisaccharides