Isolation and characterization of a novel immunomodulatory α-glucan-protein complex from the mycelium of Tricholoma matsutake in basidiomycetes
Isolation and characterization of a novel immunomodulatory α-glucan-protein complex from the mycelium of Tricholoma matsutake in basidiomycetes
复制标题
DOI：
10.1021/jf0510743
复制
发表时间：
2005-11-16
影响因子：
6.1
通讯作者：
Yasuhara, T
中科院分区：
文献类型：
--
作者：
Hoshi, H;Yagi, Y;Yasuhara, T
松茸（Tricholoma matsutake）是日本的一种高级食用菌，具有良好的生物活性，但其子实体的培养困难，产量有限，限制了其深入研究。我们已经开发了一种在罐中培养的方法，使菌丝体的大量供应成为可能。该制剂（CM 6271）对小鼠和大鼠的免疫功能有调节作用。在这项研究中，CM 6271的氢氧化钠提取物脱脂，然后用离子交换色谱和凝胶过滤的组合进行分级分离，以确定参与活性表达的组分，并用反相色谱法获得单峰级分（MPG-1）。MPG-1是相对分子质量为360 kDa的糖蛋白（糖：蛋白质比，94.3：5.7），糖部分含有约90%的葡萄糖。NMR光谱和甲基化分析表明，α-1，4-键是主要的葡聚糖键，α-1，6-键和α-1，2-键占少数。蛋白质部分的氨基酸组成富含谷氨酰胺、丙氨酸、天冬酰胺、亮氨酸、甘氨酸、缬氨酸、丝氨酸、苏氨酸、异亮氨酸和脯氨酸。MPG-1对淀粉酶或蛋白酶的降解具有抗性。MPG-1的口服给药以剂量依赖的方式促进了因束缚应激负荷而降低的小鼠自然杀伤细胞活性和血清IL-12水平的恢复。表达该作用所需的MPG-1（25 mg/kg）剂量降低至CM 6271（300 mg/kg）的1/12。此外，MPG-1在体外与TGF-β 1形成复合物，通过与其活性形式结合来调节TGF-β 1的生物活性。这些结果表明，松茸菌丝体含有一种新的α-葡聚糖-蛋白质复合物，具有免疫调节活性。
Tricholoma matsutake, a high-class edible mushroom in Japan, has been reported to have excellent biological activities, but difficulty in cultivating the fruit bodies and limited bulk availability have restricted detailed studies. We have developed a method of culturing in tanks, enabling the bulk supply of the mycelia. The preparation (CM6271) exerts modulative effects on the immune competence of mice and rats. In this study, a sodium hydroxide extract of CM6271 was defatted followed by fractionation with a combination of ion exchange chromatography and gel filtration in order to identify the components involved in the expression of the activity, and a single peak fraction (MPG-1) was obtained with reversed phase chromatography. MPG-1 was a glycoprotein (sugar:protein ratio, 94.3:5.7) with a relative molecular mass of 360 kDa, and the sugar moiety contained about 90% glucose. NMR spectra and methylation analysis revealed that the alpha-1,4-linkage was the predominant glucan linkage with alpha-1,6- and alpha-1,2-linkages in the minority. The amino acid composition in the protein moiety was rich in glutamine, alanine, asparagine, leucine, glycine, valine, serine, threonine, isoleucine, and proline. MPG-1 was resistant to degradation with amylase or protease. The oral administration of MPG-1 promoted, in a dose-dependent manner, the recovery of the mouse natural killer cell activity and serum IL-12 level that had been reduced by the loading of restraint stress. The dose of MPG-1 (25 mg/kg) required for the expression of the effect decreases to 1/12 of that of CM6271 (300 mg/kg). Furthermore, MPG-1 formed a complex with TGF-beta 1 in vitro, modulating the biological activity of TGF-beta 1 by binding to its active form. These results indicate that the mycelium of T matsutake contains a novel alpha-glucan-protein complex with immunomodulatory activities.