Purification, characterization, and molecular cloning of lectin from winter buds of Lysichiton camtschatcensis (L.) Schott.
A novel lectin was purified to homogeneity from winter buds of Lysichiton camtschatcensis (L.) Schott of the Araceae family. It was a tetramer composed of two non-covalently associated polypeptides with small subunits (11 kDa) and large subunits (12 kDa). Sequencing of both subunits yielded unique N-terminal sequences. A cDNA encoding the lectin was cloned. The isolated cDNA contained an open reading frame that encoded 267 amino acids. It encoded both subunits, indicating that the lectin is synthesized as a single precursor protein that is post-translationally processed into two different subunits with 45% sequence identity. Each subunit contained a mannose-binding motif known to be conserved in monocot mannose-binding lectins, but its activity was not inhibited by monosaccharides, including methyl α-mannoside. Asialofetuin and yeast invertase were potent inhibitors. Lectin activity was detected in the buds formed during the winter season but not in the expanded leaves.
Department of Bioproduction, Faculty of Bioindustry, Tokyo University of Agriculture, Abashiri, Hokkaido, Japan.
Yuichiro
Y
Nakagawa
Hikaru
H
Sakamoto
Hiroaki
H
Tateno
Jun
J
Hirabayashi
Suguru
S
Oguri
D000595:Amino Acid Sequence; D029064:Araceae / Q000235:genetics* / Q000254:growth & development; D001483:Base Sequence; D050260:Carbohydrate Metabolism; D003001:Cloning, Molecular; D008969:Molecular Sequence Data; D037121:Plant Lectins / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification* / Q000378:metabolism; D018520:Plant Shoots / Q000235:genetics* / Q000254:growth & development; D012621:Seasons; D013379:Substrate Specificity
D037121:Plant Lectins