Mucin binding mitogenic lectin from freshwater Indian gastropod Belamyia bengalensis: purification and molecular characterization.
A lectin was purified from the hemolymph of the freshwater Indian gastropod Belamyia bengalensis. The purification involved successive ion-exchange chromatography on Resource Q and gel filtration on Superose 12 column in FPLC system. Homogeneity of the protein was confirmed by polyacrylamide gel electrophoresis. Belamyia bengalensis lectin (BBL) was a monomeric protein with a molecular weight of 33 kDa as demonstrated by gel filtration and SDS-PAGE. It is a glycoprotein containing 6% total sugar and its activity is highly dependent on Ca(2+). BBL agglutinated human erythrocytes and is a blood group non-specific lectin. It agglutinated animal erythrocytes also. Hapten inhibition studies indicated that BBL shows binding specificity only for N-acetyl-D-glucosamine and N-acetyl-D-galactosamine at a high concentration among the mono- and oligosaccharides tested. Among the glycoproteins used for hemagglutination-inhibition assay, porcine submaxillary mucin was found to be the best inhibitor. Chemical modification studies indicated that Lys, Arg, and Trp are essential for the sugar-binding activity of BBL. Circular dichroism spectra revealed high content of alpha-helical structure in the lectin. BBL is a potent mitogen as it stimulated the T-lymphocyte proliferation, specifically the Th1 subset.
Banerjee
S
S
Department of Biological Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India.
Chaki
S
S
Bhowal
J
J
Chatterjee
B P
BP
D000596:Amino Acids / Q000737:chemistry / Q000378:metabolism; D000818:Animals; D015153:Blotting, Western; D002413:Cations, Divalent / Q000494:pharmacology; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D005688:Galactosamine / Q000031:analogs & derivatives / Q000378:metabolism / Q000494:pharmacology; D005944:Glucosamine / Q000031:analogs & derivatives / Q000378:metabolism / Q000494:pharmacology; D006023:Glycoproteins / Q000378:metabolism / Q000494:pharmacology; D006384:Hemagglutination / Q000187:drug effects / Q000502:physiology; D006458:Hemolymph / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D037102:Lectins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism* / Q000494:pharmacology*; D051379:Mice; D008934:Mitogens / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology*; D009077:Mucins / Q000378:metabolism*; D011485:Protein Binding; D017433:Protein Structure, Secondary; D012908:Snails / Q000737:chemistry*; D013379:Substrate Specificity
D000596:Amino Acids; D002413:Cations, Divalent; D006023:Glycoproteins; D037102:Lectins; D008934:Mitogens; D009077:Mucins; D005688:Galactosamine; D005944:Glucosamine