Isolation and characterization of an antifungal peptide with antiproliferative activity from seeds of Phaseolus vulgaris cv. 'Spotted Bean'

• Published in: Applied microbiology and biotechnology 2007-02, Vol.74 (1), p.125-130
• Main Authors: Wang, H. X, Ng, T. B
• Format: Article
• Language: English
• Subjects: Antifungal Agents - chemistry; Antifungal Agents - isolation & purification; Antifungal Agents - pharmacology; Antineoplastic Agents - pharmacology; Ascomycota - drug effects; Beans; Biological and medical sciences; Biotechnology; Cell Line, Tumor; Cell Proliferation - drug effects; Cellulose; Chromatography; Fundamental and applied biological sciences. Psychology; Fusarium - drug effects; Fusarium oxysporum; Human immunodeficiency virus 1; Humans; Ion exchange; Leukemia; Liquid chromatography; Microbial Sensitivity Tests; Mycosphaerella arachidicola; Peptides; Peptides - chemistry; Peptides - isolation & purification; Peptides - pharmacology; Phaseolus - chemistry; Phaseolus - growth & development; Phaseolus vulgaris; Plant Proteins - chemistry; Plant Proteins - isolation & purification; Plant Proteins - pharmacology; Seeds - chemistry
• ISSN: 0175-7598; 1432-0614
• DOI: 10.1007/s00253-006-0650-9

A 7.3-kDa antifungal peptide with an N-terminal sequence exhibiting remarkable homology to defensins from other leguminous plants was isolated from Phaseolus vulgaris cv. 'Spotted Bean'. The isolation procedure involved ion exchange chromatography on O-diethylaminoethyl (DEAE) cellulose, affinity chromatography on Affi-gel blue gel, ion exchange chromatography on SP-Sepharose, and gel filtration by fast protein liquid chromatography on Superdex 75. The peptide was unadsorbed on DEAE-cellulose and adsorbed on Affi-gel blue gel and SP-Sepharose. It exerted an antifungal action on Fusarium oxysporum and Mycosphaerella arachidicola. It inhibited mycelial growth in F. oxysporum with an IC₅₀ value of 1.8 μM. It suppressed [methyl-³H]-thymidine incorporation by leukemia L1210 cells and MBL2 cells with an IC₅₀ value of 4.0 and 9.0 μM, respectively. There was no effect on HIV-1 reverse transcriptase activity when the peptide was tested up to 0.1 mM.