title: Purification and characterization of a glucosamine-binding antifungal lectin from Phaseolus vulgaris cv. Chinese pinto beans with antiproliferative activity towards nasopharyngeal carcinoma cells.
abstract: A lectin has successfully been isolated from Phaseolus vulgaris cv. Chinese pinto bean using affinity chromatography, ion exchange chromatography, and gel filtration in succession, with a 15.4-fold purification. Investigation of its characteristics revealed that Chinese pinto bean lectin (CPBL) was a 58-kDa dimeric glucosamine-binding protein. Its Mg(2+)-dependent hemagglutinating activity was stable at pH 7-8 and at or below 60 °C. When the purified lectin was tested against six fungal species including Phyllosticta citriasiana, Magnaporthe grisea, Bipolans maydis, Valsa mali, Mycosphaerella arachidicola, and Setosphaeria turcica, only the mycelial growth of V. mali was reduced by 30.6 % by the lectin at 30 μM. The lectin did not exert any discernible antiproliferative effects on breast cancer MCF-7 cells, but was able to suppress proliferation of nasopharyngeal carcinoma HONE-1 cells, with an IC50 of 17.3 μM, as revealed by the MTT assay. Since few plant lectins demonstrate antifungal activity against V. mali, and not many others have inhibitory effects on HONE-1 cells, CPBL is a distinctive lectin which may be exploited for development into an agent against V. mali and HONE-1 cells.
authors.affiliation: Faculty of Science, School of Life Sciences, The Chinese University of Hong Kong, Hong Kong, China.
authors.forename: Andrew Si Wo
authors.initials: AS
authors.lastname: Ang
authors.forename: Randy Chi Fai
authors.initials: RC
authors.lastname: Cheung
authors.forename: Xiuli
authors.initials: X
authors.lastname: Dan
authors.forename: Yau Sang
authors.initials: YS
authors.lastname: Chan
authors.forename: Wenliang
authors.initials: W
authors.lastname: Pan
authors.forename: Tzi Bun
authors.initials: TB
authors.lastname: Ng
mesh_terms: D000818:Animals; D000935:Antifungal Agents / Q000302:isolation & purification* / Q000494:pharmacology*; D000970:Antineoplastic Agents / Q000302:isolation & purification / Q000494:pharmacology; D050260:Carbohydrate Metabolism / Q000187:drug effects; D002277:Carcinoma; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D004354:Drug Screening Assays, Antitumor; D004591:Electrophoresis, Polyacrylamide Gel; D005944:Glucosamine / Q000378:metabolism*; D006384:Hemagglutination / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D007477:Ions; D008670:Metals / Q000494:pharmacology; D008970:Molecular Weight; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000473:pathology*; D027805:Phaseolus / Q000737:chemistry*; D037121:Plant Lectins / Q000302:isolation & purification* / Q000494:pharmacology*; D011817:Rabbits; D013696:Temperature
chemical_list: D000935:Antifungal Agents; D000970:Antineoplastic Agents; D007477:Ions; D008670:Metals; D037121:Plant Lectins; D005944:Glucosamine