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Development of DNA, RNA Relating Enzyme-Inhibitory Polysaccharides, Analysis of Their Inhibition Mechanism and the Application

DNA、RNA相关酶抑制多糖的研制及其抑制机制分析及应用

基本信息

批准号：
63860014
负责人：
OISHI Kunio
金额：
$ 4.1万
依托单位：
Nihon University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Developmental Scientific Research (B).
财政年份：
1988
资助国家：
日本
起止时间：
1988 至 1990
项目状态：
已结题

项目摘要

Inhibitory activity of polysaccharides on 5 restriction enzymes, 2 DNA ligases, and 3 reverse transcriptases was investigated. All the saccharides inhibitory to these enzymes were the ones sulfated. The inhibition was derived from the binding of these polysaccharides to enzyme proteins, but not from the binding to the substrate DNA and RNA. Therefore the level of inhibition was enzyme-dependent. Reverse transcriptases from mammal pathogens were more sensitive to polysaccharides than those from avian pathogens and DNA ligases were far more resistant to polysaccharides than reverse transcriptases.Hot water extracts of seaweeds were good sources of DNA, RNA relating enzyme-inhibitory polysaccharides. Effective constituents in these extracts were fucan sulfates in the cases of brown algae and carrageenans in the cases of red algae. Sulfur contents of these seaweed saccharide preparations were lower than those of heparin and other mucopolysaccharides of animal origin, but their inhibitory a … More ctivity was much higher than the polysaccharides from animals. These facts indicate that, in addition to the level of sulfation of saccharides, structure of the saccharide chains and the positions of sulfate in saccharide moieties have an important role for the inhibitory activity.Effective constituents in the extracts of herbs and spices were identified to be flavonoids and tannins, but glycosylation of these substances appears to be essential for the inhibitory activity.Carrageenans form gels when their hot solutions were poured into CaCl_2 solution or just cooled and, in addition, they can bind to a number of restriction enzymes with different affinities. Beads and filaments of carrageenans were regarded as good affinity gels for the purification of restriction enzymes.Crude preparations of fucan sulfate from Eisenia arborea and of clove extracts were highly inhibitory to the reverse transcriptases from M-MuLV and HIV, and the infection of HIV to MT-4 cells was completely inhibited by these preparations at the concentrations of as low as 0.15 mug/ml and 10-100 mug/ml, respectively. Less

研究了多糖对5种限制性内切酶、2种DNA连接酶和3种逆转录酶的抑制活性。所有抑制这些酶的糖类都是硫酸盐酸化的。抑制作用来源于这些多糖与酶蛋白的结合，而不是与底物DNA和RNA的结合。因此，抑制水平是酶依赖性的。来自哺乳动物病原体的逆转录酶比来自禽类病原体的逆转录酶对多糖更敏感，DNA连接酶对多糖的抗性远高于逆转录酶。海藻热水提取物是DNA、RNA相关酶抑制多糖的良好来源。这些提取物的有效成分分别是褐藻中的岩藻聚糖硫酸盐和红藻中的角叉菜胶。这些海藻糖制剂的硫含量低于肝素和其他动物源性粘多糖，但其抑菌活性远高于动物源性多糖。这些事实表明，除了糖的磺化程度外，糖链的结构和硫酸根在糖基中的位置对抑制活性也有重要作用。草药和香料提取物中的有效成分被确定为黄酮类化合物和单宁，但这些物质的糖基化似乎是抑制活性所必需的。当将其热溶液倒入氯化钙溶液中或冷却时，卡拉胶形成凝胶，此外，它们可以与许多不同亲和力的限制性内切酶结合。角叉菜胶珠和细丝被认为是纯化限制性内切酶的良好亲和凝胶。紫杉树和丁香提取物的硫酸富聚糖粗制剂对M-MuLV和HIV的逆转录酶具有较强的抑制作用，浓度分别为0.15和10-100马克/毫升时，可完全抑制HIV对MT-4细胞的感染。少