title: Purification and characterization of a lectin from Arisaema tortuosum Schott having in-vitro anticancer activity against human cancer cell lines.
abstract: A lectin with in-vitro anticancer activity against established human cancer cell lines has been purified by affinity chromatography on asialofetuin-linked amino activated silica beads from the tubers of Arisaema tortuosum, popularly known as Himalayan Cobra lily, a monocot plant from the family Araceae. The bound Arisaema tortuosum lectin (ATL) was eluted with glycine-HCl buffer, pH 2.5. ATL was effectively inhibited by asialofetuin, a complex desialylated serum glycoprotein as well as by N-acetyl-D-lactosamine, a disaccharide. It gave a single band corresponding to a subunit molecular weight of 13.5 kDa in SDS-PAGE, pH 8.8 both under reducing and non-reducing conditions. When subjected to gel-filtration on Biogel P-200, it was found to have a molecular weight of 54 kDa, suggesting a homotetramer structure, in which individual polypeptides are not bound to each other with disulfide bonds. ATL is a glycoprotein with 0.9 % carbohydrate content, stable up to 55(o)C and at pH 2 to 10. The lectin had no requirement for divalent metal ions i.e. Ca(2+) and Mn(2+) for its activity. However, as reported for other monocot lectins, ATL gave multiple bands in isoelectric focusing and Native PAGE, pH 8.3. The lectin was found to inhibit in vitro proliferation of human cancer cell lines HT29, SiHa and OVCAR-5.
authors.affiliation: Department of Molecular Biology and Biochemistry, Guru Nanak Dev University, Amritsar.
authors.forename: Vikram
authors.initials: V
authors.lastname: Dhuna
authors.forename: Jagmohan Singh
authors.initials: JS
authors.lastname: Bains
authors.forename: Sukhdev Singh
authors.initials: SS
authors.lastname: Kamboj
authors.forename: Jatinder
authors.initials: J
authors.lastname: Singh
authors.forename: Shanmugavel
authors.initials: S
authors.lastname: Kamboj
authors.forename: Ajit Kumar
authors.initials: AK
authors.lastname: Saxena
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000302:isolation & purification* / Q000378:metabolism* / Q000494:pharmacology; D031057:Arisaema / Q000737:chemistry*; D050260:Carbohydrate Metabolism; D002241:Carbohydrates / Q000737:chemistry; D045744:Cell Line, Tumor / Q000187:drug effects*; D006801:Humans; D007525:Isoelectric Focusing; D008970:Molecular Weight; D037121:Plant Lectins / Q000302:isolation & purification* / Q000378:metabolism* / Q000494:pharmacology
chemical_list: D000970:Antineoplastic Agents; D002241:Carbohydrates; D037121:Plant Lectins