PURIFICATION OF A LECTIN IN HIGH-YIELD FROM THE INDIAN LABLAB BEANS ON GOAT IGM SEPHAROSE AND BY IMMUNOAFFINITY CHROMATOGRAPHY - EVIDENCE FOR THE PRESENCE OF ENDOGENOUS LECTIN RECEPTORS

Seeds of the Dolichos lab lab var. typicus (Indian lablab beans) conta in a glucose/mannose specific lectin that has been affinity purified o n Sepharose-mannose columns (1). We report here on the affinity purifi cation of this lectin in high yields using alternate methods i) goat I gM Sepharose., and ii) Immuno-affinity chromatography (Lectin specific IgG coupled to Affi-gel-10). The molecular size and subunit pattern o f the lectin purified by both methods was similar to that reported ear lier. In addition the purified lectin could be quantitatively bound to Sepharose divinyl sulfone methyl alpha-mannopyranoside gel. Purified lectin was also found to be mitogenic to murine lymphocytes. Additiona lly Lectin-affinity chromatography (Lectin coupled to Affigel-10) indi cated the presence of endogenous lectin receptors that specifically in teract with the lectin without the involvement of the sugar binding si te.