Isolation of a lectin and a galactoxyloglucan from Mucuna sloanei seeds.
A lectin and a galactoxyloglucan were characterized from Mucuna sloanei seed cotyledons. The galactoxyloglucan, isolated by water extraction and ethanol precipitation, had Glc:Xyl:Gal proportions in a molar ratio of 1.8:1.7:1.0 and a molar mass (M(w)) of 1.6x10(6)g mol(-1). The lectin (sloanin), isolated from the same seed by affinity chromatography on cross-linked Adenanthera pavonina galactomannan, gave two protein bands by SDS-PAGE (36 and 34 kDa) and one peak by gel filtration (63.6 kDa). Its N-terminal sequence indicated approximately 69% identity with soybean agglutinin to leguminous lectins. Circular dichroism (CD) spectra established that sloanin predominantly contains beta-sheet structures. Sloanin has approximately 5.5% carbohydrate and displayed hemagglutinating activity against rabbit and enzyme treated human erythrocytes, inhibited only by D-Gal containing sugars. The interaction between sloanin and storage cell-wall galactoxyloglucan was tested by affinity chromatography and fluorescence spectroscopy.
Laboratório de Lectinas e Glicoconjugados, Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Ceará, Caixa Postal 6020, CEP 60451-980 Fortaleza, CE, Brazil. d_teixeira@uece.br
Daniele M A
DM
Teixeira-Sá
Fany
F
Reicher
Renata C
RC
Braga
Leila Maria
LM
Beltramini
Renato
R
de Azevedo Moreira
D000595:Amino Acid Sequence; D000818:Animals; D002241:Carbohydrates; D002846:Chromatography, Affinity; D002942:Circular Dichroism; D004591:Electrophoresis, Polyacrylamide Gel; D004912:Erythrocytes / Q000187:drug effects; D005690:Galactose / Q000031:analogs & derivatives; D005936:Glucans / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D006388:Hemagglutinins / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D006801:Humans; D008351:Mannans; D015394:Molecular Structure; D031299:Mucuna / Q000737:chemistry*; D037121:Plant Lectins / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism / Q000494:pharmacology; D011817:Rabbits; D012639:Seeds / Q000737:chemistry; D017385:Sequence Homology
D002241:Carbohydrates; D005936:Glucans; D006388:Hemagglutinins; D008351:Mannans; D037121:Plant Lectins; C012990:galactomannan; D005690:Galactose