Characterization and sugar-binding properties of arcelin-1, an insecticidal lectin-like protein isolated from kidney bean (Phaseolus vulgaris L. cv. RAZ-2) seeds

Abstract

Arcelin-1 is a lectin-like protein found in the seeds of wild varieties of the kidney bean (Phaseolus vulgaris). This protein displays insecticidal properties, but the mechanism of action is as yet unknown. In the present study we investigated the biochemical and biophysical properties of arcelin-1 from Phaseolus vulgaris cv. RAZ-2. Native arcelin-1 is a dimeric glycoprotein of 60 kDa, built from the non-covalent association of two identical monomers. This dimer resists dissociation by chaotropic agents and is highly resistant to proteolytic enzymes. Each subunit contains 10% (w/w) neutral sugars which belong to the high-mannose and complex-type glycans attached to three glycosylation sites. No interaction of the protein with simple sugars could be detected, but arcelin-1 displays an intrinsic specificity in binding complex glycans. Arcelin-1 therefore differs from the closely related phytohaemagglutinin lectins and alpha-amylase inhibitor in several respects: oligomerization states, sugar-binding affinities and the type and number of glycan chains. These features may be related to the toxicity of arcelin-1.

Purification and cDNA cloning of a lectin and a lectin-like protein from Apios americana Medikus tubers

“…18) Both proteins have insecticidal activity toward bean weevils, and their amino acid sequences are very similar (50-60% identity) to that of PHA-L, a lectin occurring in the same seed. Although some of the arcelins show lectin activity, 23,24) the α-amylase inhibitor has none. AALP also showed high sequence identity to various legume lectins (38-58%) though it has no hemagglutinating activity, but AALP did not inhibit α-amylases from A. oryzae or porcine pancreas.…”

Localization and in vitro binding studies suggest that the cytoplasmic/nuclear tobacco lectin can interact in situ with high‐mannose and complex N‐glycans

“…To test the validity of this approach the same experiments were done with arcelin-1, a glycoprotein from kidney bean (Phaseolus vulgaris L. cv. RAZ-2) seeds that was previously shown to interact with Nictaba [6] and is known to contain two high-mannose and one complex N-glycan per subunit [13,14]. As shown in Fig.…”

Structural basis for the unusual carbohydrate-binding specificity of jacalin towards galactose and mannose

“…According to the change in SPR response caused by immobilization on the carboxymethylated-dextran layer covering the sensor chip, an estimated surface concentration of 10 ng of immobilized protein\ mm# of dextran was obtained. Arcelin-1 contains mainly highmannose-type N-glycans [16], whereas asialofetuin contains a mixture of N-and O-linked glycans with terminal galactose residues [17,18]. Both proteins possess glycans with a more or less exposed trimannoside core, Manα1-6(Manα1-3)Man, which is known to interact specifically with the extended carbohydratebinding site of many lectins, such as concanavalin A [19].…”

“…Asialofetuin, simple and complex sugars, and other chemicals were purchased from Sigma. Arcelin-1 was purified from kidney bean seeds (Phaseolus ulgaris L. cv RAZ-2) according to [16]. Seeds were a gift from Dr C. Cardona (Centro Internacional de Agricultura Tropical, Cali, Columbia).…”