title: Amino acid sequence and some properties of lectin-D from the roots of pokeweed (Phytolacca americana).
abstract: Two pokeweed lectins, designated PL-D1 and PL-D2, have been isolated from the roots of pokeweed (Phytolacca americana) using chitin affinity column chromatography followed by gel filtration on a Sephacryl S-200 column and fast protein liquid chromatography on a Mono-Q column, and their amino acid sequences have been analyzed. PL-D1 consists of 84 amino acid residues and has a molecular mass of 9317, while PL-D2 has an identical sequence with PL-D1 except lack of the C-terminal Leu-Thr. PL-D is composed of two chitin-binding domains, A and B, with 50% homology with each other. Both PL-Ds did not agglutinate native rabbit erythrocytes, but showed about 0.1% of the agglutinating activity of wheat germ agglutinin toward trypsin-treated erythrocytes. In the presence of beta (1-->4) linked oligomers of N-acetyl-D-glucosamine, which inhibit the hemagglutination, PL-D1 had an ultraviolet-difference spectrum with maxima at 292-294 nm and 284-285 nm, attributed to the red shift of the tryptophan residue, suggesting the location of tryptophan residue(s) at or near saccharide-binding site of PL-D1.
authors.affiliation: Laboratory of Protein Chemistry and Engineering, Faculty of Agriculture, Kyushu University, Fukuoka, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Yamaguchi
authors.forename: A
authors.initials: A
authors.lastname: Mori
authors.forename: G
authors.initials: G
authors.lastname: Funatsu
mesh_terms: D000117:Acetylglucosamine / Q000737:chemistry; D000595:Amino Acid Sequence; D000818:Animals; D002236:Carbohydrate Conformation; D002352:Carrier Proteins / Q000737:chemistry*; D002686:Chitin / Q000737:chemistry*; D004912:Erythrocytes / Q000187:drug effects; D006386:Hemagglutination Tests; D008969:Molecular Sequence Data; D037121:Plant Lectins; D018517:Plant Roots / Q000737:chemistry*; D011043:Pokeweed Mitogens / Q000737:chemistry*; D017434:Protein Structure, Tertiary; D011817:Rabbits; D054788:Ribosome Inactivating Proteins; D017386:Sequence Homology, Amino Acid
chemical_list: D002352:Carrier Proteins; D037121:Plant Lectins; D011043:Pokeweed Mitogens; D002686:Chitin; C104076:pokeweed lectin D; D054788:Ribosome Inactivating Proteins; D000117:Acetylglucosamine