tailieunhanh - Báo cáo " Tinh chế và mô tả sơ bộ đặc tính của những lectin từ ba dòng màu của tảo đỏ Kappaphycus alvarezii (Doty) Doty ex silva "

Tinh chế và mô tả sơ bộ đặc tính của những lectin từ ba dòng màu của tảo đỏ Kappaphycus alvarezii (Doty) Doty ex silva | Tạp chỉ Công nghệ Sinh học 5 4 453-461 2007 PURIFICATION AND PRELIMINARY CHARACTERIZATION OF LECTINS FROM THREE COLOR STRAINS OF THE RED MARINE ALGA KAPPAPHYCUS ALVAREZII DOTY DOTY EX SILVA Le Dinh Hung1 2 Kanji Hori2 lNhatrang Institute of Technology Research and Application Vietnam 2Graduate School of Biosphere Science Hiroshima University Japan SUMMARY The three lectins named KAA-1 KAA-2 and KAA-3 after the specific name of alga were isolated from each color strains of the red marine alga Kappaphycus alvarezii by combination of gel filtration and ion exchange chromatography from the 80 cold ethanol precipitates. The highest yield of KAAs was fresh tissue for the red strain next was fresh tissue for the green strains and the lowest was 1 fresh tissue for brown strains. The lectins had a molecular mass of 28000 500 Da on SDS-PAGE in both non-reducing and reducing condition respectively. Biochemical studies revealed that KAA-1 and KAA-2 are monomeric proteins without a carbohydrate moiety and had almost identical 20 N-terminal amino acid sequence to each other and only differed in the isoelectric point indicating that they are isolectins to each other. The hemagglutination activities of KAAs were inhibited strongly by glycoproteins bearing high mannose type N-glycan as porcine thyroglobulin and yeast mannan so far as tested. The activities of KA As were not affected by either the presence of EDTA or addition of divalent cations was stable in a wide pH range from 3 to 10 and was not changed by incubation at 50 C for 30 min. Keywords Carbohydrate-binding specificity hemagglutinins Kappaphycus alvarezii lectins N-terminal amino acid sequence three color strains INTRODUCTION Lectins are carbohydrate-binding proteins other than immunoglobulins and are a highly diverse group of proteins found in most organisms ranging from viruses and bacteria to plants and animals Gabius 1997 Sahron Lis 2003 . The occurrence of hemagglutinins in extracts .