title: Purification and characterization of three galactose specific lectins from mulberry seeds (Morus sp.).
abstract: Three lectins were extracted and purified from mulberry seeds by gel filtration of 100% ammonium sulfate saturated crude protein extract followed by ion-exchange chromatography on DEAE and CM-cellulose. The lectins were found to be homogeneous as judged by polyacrylamide disc gel electrophoresis. The molecular masses of the lectins as determined by gel filtration were 175 000 for MSL-1, 120 000 for MSL-2 and 89 500 for MSL-3. MSL-1 is dimer in nature, with the two monomers held together by disulfide bond(s), while MSL-2 and MSL-3 contain four nonidentical subunits that are held together by nonionic hydrophobic interactions. The lectins agglutinated rat red blood cells and this agglutination was inhibited specifically by galactose, methyl-alpha-d-galactopyranoside, methyl-beta-d-galactopyranoside, lactose and raffinose. The lectins MSL-1, MSL-2 and MSL-3 contained 5.7, 5.4 and 4.5% neutral sugars, respectively, and the sugar composition of the lectins was glucose and mannose for MSL-1 and galactose for both MSL-2 and MSL-3. The lectins exhibited strong cytotoxic effect in brine shrimp lethality bioassay.
authors.affiliation: Department of Biochemistry, University of Rajshahi, Rajshahi-6205, Bangladesh. rajucc@citechco.net
authors.forename: T
authors.initials: T
authors.lastname: Yeasmin
authors.forename: M A
authors.initials: MA
authors.lastname: Tang
authors.forename: A
authors.initials: A
authors.lastname: Razzaque
authors.forename: N
authors.initials: N
authors.lastname: Absar
mesh_terms: D000818:Animals; D001156:Artemia / Q000187:drug effects; D002241:Carbohydrates / Q000032:analysis; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D019281:Dimerization; D005260:Female; D005690:Galactose / Q000494:pharmacology; D006384:Hemagglutination / Q000187:drug effects; D066298:In Vitro Techniques; D037102:Lectins / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology / Q000633:toxicity; D008970:Molecular Weight; D010063:Ovum / Q000187:drug effects; D037121:Plant Lectins; D021122:Protein Subunits; D051381:Rats; D019685:Rosales / Q000737:chemistry*; D012639:Seeds / Q000737:chemistry
chemical_list: D002241:Carbohydrates; D037102:Lectins; D037121:Plant Lectins; D021122:Protein Subunits; D005690:Galactose