Psathyrella velutina Mushroom Lectin Exhibits High Affinity toward Sialoglycoproteins Possessing TerminalN-Acetylneuraminic Acid α2,3-Linked to Penultimate Galactose Residues of Trisialyl N-Glycans

Abstract

A lectin from the fruiting body of the Psathyrella velutina mushroom (PVL) was found to bind specifically to N-acetylneuraminic acid, as well as to GlcNAc (Ueda, H., Kojima, K., Saitoh, T., and Ogawa, H. (1999) FEBS Lett. 448, 75-80). In this study, the glycan sequences that PVL recognizes with high affinity on sialoglycoproteins were revealed. Among sialic acid-specific lectins only PVL could reveal the sialylated N-acetyllactosamine structure of glycoproteins in blotting studies, based on the dual specificity. The affinity of PVL to fetuin was measured by surface plasmon resonance to be 10 7 M ؊1 , which is an order of magnitude higher than those of Sambucus nigra agglutinin and Maackia amurensis mitogen, whereas affinity to asialofetuin was ϳ0 and to asialoagalactofetuin was 10 8 M ؊1 , suggesting that PVL exhibits remarkably high affinities toward glycoproteins possessing trisialo-or GlcNAc-exposed glycans. Transferrin was separated into fractions that correspond to the sialylation states on an immobilized PVL column. Transferrin-possessing trisialoglycans containing ␣2,3-linked N-acetylneuraminic acid on the ␤1,4-linked GlcNAc branch bound to the PVL column and eluted with GlcNAc; those containing only ␣2,6-linked sialic acids were retarded, whereas other transferrin fractions passed through the column. These results indicate that PVL is a lectin with potential for separation and detection of sialoglycoproteins because of its dual specificity toward sialoglycans and GlcNAc exposed glycans.Sialic acids play an important role as ligands in cell sociology. Sialylation of glycoproteins changes under pathological conditions as well as during developmental stages, and altered sialylation often has significant implications in the physiological role of glycoproteins (1-3). Lectins that recognize the linkages or modifications of sialic acid are therefore indispensable as reagents in biochemical research and diagnostic analyses.Among sialic acid-specific lectins purified from plants and other sources, several lectins have been employed as tools for the detection and separation of sialic acid-containing glycoconjugates (3, 4). Lectins that distinguish various linkages of sialic acid are elderberry bark lectin (SNA 1 ; Sambucus nigra agglutinin) (5), Japanese elderberry lectin (SSA; S. sieboldiana agglutinin) (6), and Polyporus squamosus lectin (7) that are specific for NeuAc␣2,6Gal/GalNAc sequences; Maackia amurensis mitogen (MAL) that reacts with greatest affinity to the trisaccharide sequence NeuAc/Gc␣2,3Gal␤1,4GlcNAc/Glc, which is usually present in N-linked oligosaccharides (8), and the hemagglutinin from the same source (MAH) that displays higher affinity for a disialylated tetrasaccharide found in the O-linked oligosaccharide, NeuAc␣2,3Gal␤1,3(NeuAc␣2,6)GalNAc␣ (9). In contrast to these sequence-specific lectins, wheat germ lectin (WGA) and Limax flavus lectin have been used as general tools to bind sialylated glycoconjugates (10, 11). A mushroom lectin from Hericum erinaceum recognizes N-glycolylneuraminic acid...

Preferential reduction of the α-2-6-sialylation from cell surface N-glycans of human diploid fibroblastic cells by in vitro aging

“…4 LCA). A similar result was obtained when the blotted membrane was incubated with PVL, which interacts with oligosaccharides terminated with β-Nacetylglucosamine residue [23] and also with α2-3-sialylated oligosaccharides [24] (Fig. 4 PVL).…”

Entomotoxic and nematotoxic lectins and protease inhibitors from fungal fruiting bodies

“…Homodimer 4 Gal na Entomotoxic (Hamshou et al 2013;Hamshou et al 2010b;Hamshou et al 2012;Skamnaki et al 2013) Bleuler-Martinez et al 2011;Fujihashi et al 2003;Fukumori et al 1990;Kochibe and Furukawa 1980;Olausson et al 2010;Olausson et al 2008;Tateno et al 2009;Wimmerova et al 2003) GlcNAc-β1,4-X na nd (Cioci et al 2006;Ueda et al 1999a;Ueda et al 2002;Ueda et al 1999b;Ueda et al 2003) Entomotoxic (Birck et al 2004;Bleuler-Martinez et al 2011;Damian et al 2005;Francis et al 2003;Jaber et al 2008;Jaber et al 2007;…”

“…The affinity of LbTec2 for these monosaccharides is very low (millimolar range), but, according to a commonly accepted concept in the lectin field (Shinohara et al 1997), when they are displayed on a surface, the avidity to these carbohydrates could be very high due to the oligomerization of the protein. Finally, PVL, whose primary sequence is not related to AAL or LbTec2, sharing 8 and 11 % sequence identity (33 % similarity), respectively, folds into a monomeric, seven-blade β-propeller with a total of six binding sites for terminal GlcNAc or Neu5Ac residues located at the interfaces between the blades (Audfray et al 2015;Cioci et al 2006;Ueda et al 2002).…”

Galactosylation of IgG from rheumatoid arthritis (RA) patients – changes during therapy

“…IgG samples, isolated from the sera of RA patients, were run in SDS-PAGE under reducing conditions, then were transferred onto nitrocellulose and overlayed with three biotinylated lectins: Ricinus communis (RCA-I, specific for the terminal Gal residues [12]); Griffonia simplicifolia (GSL-II) [13] and Psathyrella velutina (PVL) [14]-both lectins recognize the terminal GlcNAc, but PVL is less specific and reacts also with sialic acid residues; the results obtained for six randomly chosen IgG samples are presented (Figure 1). As can be seen, either lectin reacted only with heavy chains of the analysed IgG samples.…”