Isolation and characterization of a lectin with potentially exploitable activities from caper (Capparis spinosa) seeds.
A dimeric 62-kDa lectin exhibiting a novel N-terminal amino acid sequence was purified from caper (Capparis spinosa) seeds. The purification protocol involved anion-exchange chromatography, cation-exchange chromatography and, finally, gel filtration by FPLC on Superdex 75. Approx. 100-fold purification was achieved. The haemagglutinating activity of the lectin, which was stable in the pH range 1-12 and up to 40 degrees C, could be inhibited by D(+) galactose, alpha-lactose, raffinose and rhamnose at 1 mM concentration, by 25 mM L(+)-arabinose and by 100 mM D(+)GlcN (glucosamine). The lectin potently inhibited HIV-1 reverse transcriptase with an IC50 of 0.28 microM and proliferation of both hepatoma HepG2 and breast cancer MCF-7 cells with an IC50 of approx. 2 microM. It induced apoptosis in HepG2 and MCF-7 cells. It manifested a weaker mitogenic activity on mouse splenocytes than ConA (concanavalin A). It inhibited mycelial growth in Valsa mali with an IC50 of 18 microM.
Department of Biochemistry, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, People's Republic of China.
Sze Kwan
SK
Lam
Qi Feng
QF
Han
Tzi Bun
TB
Ng
D000595:Amino Acid Sequence; D000818:Animals; D000935:Antifungal Agents / Q000494:pharmacology; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology; D001943:Breast Neoplasms / Q000188:drug therapy; D031484:Capparis / Q000737:chemistry*; D006528:Carcinoma, Hepatocellular / Q000188:drug therapy; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D003208:Concanavalin A / Q000494:pharmacology; D019281:Dimerization; D005260:Female; D005658:Fungi / Q000187:drug effects; D054303:HIV Reverse Transcriptase / Q000037:antagonists & inhibitors; D006801:Humans; D006863:Hydrogen-Ion Concentration; D020128:Inhibitory Concentration 50; D008113:Liver Neoplasms / Q000188:drug therapy; D051379:Mice; D008938:Mitosis / Q000187:drug effects; D008969:Molecular Sequence Data; D008970:Molecular Weight; D025282:Mycelium / Q000187:drug effects; D037121:Plant Lectins / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism* / Q000494:pharmacology; D055550:Protein Stability; D012639:Seeds / Q000737:chemistry* / Q000378:metabolism*; D013154:Spleen / Q000166:cytology / Q000502:physiology; D013696:Temperature
D000935:Antifungal Agents; D000972:Antineoplastic Agents, Phytogenic; D037121:Plant Lectins; D003208:Concanavalin A; D054303:HIV Reverse Transcriptase