The purpose of this work is to perform a detailed study of carbohydrate specificity of the new extracellular bacilli lectins which is considered to determine mechanisms of the lectins action. Sources of lectins were b...The purpose of this work is to perform a detailed study of carbohydrate specificity of the new extracellular bacilli lectins which is considered to determine mechanisms of the lectins action. Sources of lectins were bacterial strains from Ukrainian collection of microorganisms. The optimized protocol of bacilli lectins isolation and purification included precipitation with ammonium sulfate with subsequent gel filtration chromatography on Sepharose CL-6B. Hemagglutinating activity of bacilli lectins and their fine carbohydrate specificity to sialic acids and their derivatives as well as sialic asid-containing and asialic glycoconjugates were studied. The ability of extracellular bacilli lectins to discriminate a- and 13-conformation of carbohydrate molecule and the type of connection between the monomers was determined. Studied lectins showed the most affinity to glycoconjugates containing both types of sialic acids (N-acetylneuraminic acid (Neu5Ac) and N-glycolylneuraminic acid (NeuGc)) and it is supposed to be a basis of their diagnostic and analytical potential.展开更多
Semiparasitic plants, mistletoes, distributed in Europe and East-Asia mainly, China, Korea and Japan have long been recognised as therapeutic herbs. Since the 1920s, extracts from European mistletoe (Viscum album L)...Semiparasitic plants, mistletoes, distributed in Europe and East-Asia mainly, China, Korea and Japan have long been recognised as therapeutic herbs. Since the 1920s, extracts from European mistletoe (Viscum album L) have been popular in Europe as an unconventional cancer treatment. These extracts have been used in adjuvant cancer therapy because their immunostimulatory, cytostatic/cytotoxic and DNA stabilising activities. The main biological activities are addressed to sugar binding proteins, the Mistletoe Lectins, and to micro proteins named viscotoxins. The mistletoe lectins are members of the family of toxic lectins and recognize sugars and glycoconjugates containing galactose and/or N-acetyl-galactosamine groups. In vitro and in vivo assays confirm that the mistletoe lectins, isolated from the plant and compared with recombinant forms, play an important role as biologically active principles in mistletoe extracts. Limited experimental evidence indicates that other components like glycosides, polysaccharides, amines etc, may also have anticancer activity. Under discussion in Europe is the principal question of using holo plant extracts or single component lectin preparations: wild type lectins or recombinant ones in cancer therapy. Finally problems of preparation, characterization and standardization of commercial mistletoe preparations and evaluation of biological activities are discussed.展开更多
文摘The purpose of this work is to perform a detailed study of carbohydrate specificity of the new extracellular bacilli lectins which is considered to determine mechanisms of the lectins action. Sources of lectins were bacterial strains from Ukrainian collection of microorganisms. The optimized protocol of bacilli lectins isolation and purification included precipitation with ammonium sulfate with subsequent gel filtration chromatography on Sepharose CL-6B. Hemagglutinating activity of bacilli lectins and their fine carbohydrate specificity to sialic acids and their derivatives as well as sialic asid-containing and asialic glycoconjugates were studied. The ability of extracellular bacilli lectins to discriminate a- and 13-conformation of carbohydrate molecule and the type of connection between the monomers was determined. Studied lectins showed the most affinity to glycoconjugates containing both types of sialic acids (N-acetylneuraminic acid (Neu5Ac) and N-glycolylneuraminic acid (NeuGc)) and it is supposed to be a basis of their diagnostic and analytical potential.
文摘Semiparasitic plants, mistletoes, distributed in Europe and East-Asia mainly, China, Korea and Japan have long been recognised as therapeutic herbs. Since the 1920s, extracts from European mistletoe (Viscum album L) have been popular in Europe as an unconventional cancer treatment. These extracts have been used in adjuvant cancer therapy because their immunostimulatory, cytostatic/cytotoxic and DNA stabilising activities. The main biological activities are addressed to sugar binding proteins, the Mistletoe Lectins, and to micro proteins named viscotoxins. The mistletoe lectins are members of the family of toxic lectins and recognize sugars and glycoconjugates containing galactose and/or N-acetyl-galactosamine groups. In vitro and in vivo assays confirm that the mistletoe lectins, isolated from the plant and compared with recombinant forms, play an important role as biologically active principles in mistletoe extracts. Limited experimental evidence indicates that other components like glycosides, polysaccharides, amines etc, may also have anticancer activity. Under discussion in Europe is the principal question of using holo plant extracts or single component lectin preparations: wild type lectins or recombinant ones in cancer therapy. Finally problems of preparation, characterization and standardization of commercial mistletoe preparations and evaluation of biological activities are discussed.