comparative study on the purification of the Amaranthus leucocarpus syn. hypocondriacus lectin

• Published in: Preparative biochemistry & biotechnology Vol. 29; no. 3; pp. 219 - 234
• Main Authors: Hernandez, P, Bacilio, M, Porras, F, Juarez, S, Debray, H, Zenteno, E, Ortiz, B
• Format: Journal Article
• Language: English
• Published: England Taylor & Francis Group 01.01.1999
• Subjects: Amaranthus leucocarpus hypocondriacus; Amino Acid Sequence - genetics; Animals; Antigens, Tumor-Associated, Carbohydrate - chemistry; Antigens, Tumor-Associated, Carbohydrate - metabolism; Antigens, Viral, Tumor - chemistry; Antigens, Viral, Tumor - metabolism; binding; Carbohydrates - pharmacology; Chromatography - methods; Electrophoresis, Polyacrylamide Gel; Erythrocyte Membrane - chemistry; Erythrocyte Membrane - metabolism; Glycoproteins - genetics; Glycoproteins - isolation & purification; Glycoproteins - metabolism; Glycoproteins - pharmacology; Glycosylation; Hemagglutination - drug effects; Humans; inhibition; lectins; Lectins - isolation & purification; Lectins - pharmacology; Molecular Sequence Data; Mucins - analysis; Plant Lectins; Polysaccharides - pharmacology; Protein Conformation; purification; Rabbits; Seeds - chemistry; sugar specificity
• ISSN: 1082-6068; 1532-2297
• DOI: 10.1080/10826069908544925

Amaranthus leucocarpus lectin is a homodimeric glycoprotein of 35 kDa per sub-unit, which interacts specifically with N-acetyl-galactosamine. In this work, we compared different glycoproteins that contain Galß1-3 GalNAcα1-3 Ser/Thr or GalNAcα1-3 Ser/Thr in their structure as ligands to purify the A. leucocarpus lectin. From the glycoproteins tested, fetuin was the most potent inhibitor of the hemagglutinating activity and the better ligand for lectin purification; however, the use of desialylated stroma from erythrocytes represented the cheapest method of purify this lectin. O-linked glycans released from the glycoproteins used as affinity matrix and those from different erythrocytes were less inhibitory than parental glycoproteins. The NH 2 -terminal of the lectin is blocked; moreover, this is the only example of a lectin isolated from this genus to be a glycoprotein. Analysis of the glycoprotein sequences with inhibitory activity for the lectin, showed a different pattern in the O-glycosylation, which confirms that A. leucocarpus lectin recognizes conformation and, probably, distances among O-linked glycans moieties.