To investigate the chemical structure of cell wall mannan of pathogenic yeast, Candida catenulata IFO 0745 strain, which possess the epitopes of antigenic factors 1, 9, and 34 to genus Candida, we previously performed...To investigate the chemical structure of cell wall mannan of pathogenic yeast, Candida catenulata IFO 0745 strain, which possess the epitopes of antigenic factors 1, 9, and 34 to genus Candida, we previously performed the two-dimensional nuclear magnetic resonance (NMR) analysis of this mannan, Fr. C, without the need for harsh procedures. In this study, three oligosaccharides, biose, triose, and tetraose, and mannose were isolated from Fr. C by acetolysis. The results of NMR analysis indicate that the chemical structures of these oligosaccharides were identified to Manα1-2Man, Manα1-2Manα1-2Man, and Manα1-3Manα1-2Manα1-2Man. The most of resultant mannose seems to be originated from the α-1,6-linked mannan backbone which is recognized by antiserum to factor 9. The inhibition assay of slide agglutination reaction between Fr. C and antigenic antibodies using three oligosaccharides indicate that the Manα1-2Manα1-2Man and Manα1-3Manα1-2Manα1-2Man possess domains corresponding to immunodominants of antigenic factors 1 and 34, respectively.展开更多
To investigate the chemical structure of cell wall mannan obtained from pathogenic yeast, Candida tropicalis NBRC 1400 (former antigenic standard strain, IFO 1400). As a result of two-dimensional NMR analysis, it was ...To investigate the chemical structure of cell wall mannan obtained from pathogenic yeast, Candida tropicalis NBRC 1400 (former antigenic standard strain, IFO 1400). As a result of two-dimensional NMR analysis, it was shown that the mannan of this strain is composed of α-1,6-, α-1,3-, α-1,2- and β-1,2-linked mannose residues. In this research, the mannan was subjected to three degradation procedures, acid-treatment, α-mannosidase, and acetolysis under two conditions in order to determine the chemical structure of the antigenic oligomannosyl side chains in this molecule. The 1H-nuclear magnetic resonance spectra of resultant oligosaccharides, pentaose and hexaose, demonstrated the existence of the oligomannosyl side chains corresponding to Manα1-3Manα1-2Manα1-2Manα1-2Man and Manα1-3Manα1-2Manα1-2Manα1-2Manα1-2Man, respectively, which have previously also been found in Candida albicans serotype A strain mannans. These findings indicate that C. tropicalis and C. albicans serotype A have no significant difference in the chemical structure of these cell wall mannans. Therefore, it can be interpreted that it is extremely difficult to distinguish both species by targeting the antigenic group in these mannans.展开更多
本文利用作者研究的26科56属63种现代花粉的测量统计资料,对醋酸酐的分解作用与花粉形状体积变化的相互关系作了一些初步的探讨。应用小样本的 t 检验方法,对醋酸酐分解前后花粉粒的大小形状差异进行分析,发现:形状变化有趋长倾向,即 P...本文利用作者研究的26科56属63种现代花粉的测量统计资料,对醋酸酐的分解作用与花粉形状体积变化的相互关系作了一些初步的探讨。应用小样本的 t 检验方法,对醋酸酐分解前后花粉粒的大小形状差异进行分析,发现:形状变化有趋长倾向,即 P/E 值增加;体积变化符合伍德豪斯效应(Wodehouse effect),即本身个体小的花粉粒体积变化小,个体大的花粉粒体积变化大。球形具散孔花粉,超长球形个体很小的花粉一般不发生明显的形状和体积的变化。具沟花粉极轴增长明显;扁球形花粉较长球形花粉变化显著。外壁厚的、纹饰粗的花粉变化较大。花粉粒形体变化是醋酸酐分解破坏花粉粒内含物引起外壁张力变化的结果。展开更多
Sulfamic acid has been used as an efficient catalyst and green alternative for conventional acidic materials to promote the acetolysis reaction of THF to produce 1, 4-diacetoxybutane. This method is also applicable in...Sulfamic acid has been used as an efficient catalyst and green alternative for conventional acidic materials to promote the acetolysis reaction of THF to produce 1, 4-diacetoxybutane. This method is also applicable in the acetolysis of other cyclic ethers, such as methyl substituted THF and tetrahydropyran and 1,4-dioxane which is less reactivity.展开更多
文摘To investigate the chemical structure of cell wall mannan of pathogenic yeast, Candida catenulata IFO 0745 strain, which possess the epitopes of antigenic factors 1, 9, and 34 to genus Candida, we previously performed the two-dimensional nuclear magnetic resonance (NMR) analysis of this mannan, Fr. C, without the need for harsh procedures. In this study, three oligosaccharides, biose, triose, and tetraose, and mannose were isolated from Fr. C by acetolysis. The results of NMR analysis indicate that the chemical structures of these oligosaccharides were identified to Manα1-2Man, Manα1-2Manα1-2Man, and Manα1-3Manα1-2Manα1-2Man. The most of resultant mannose seems to be originated from the α-1,6-linked mannan backbone which is recognized by antiserum to factor 9. The inhibition assay of slide agglutination reaction between Fr. C and antigenic antibodies using three oligosaccharides indicate that the Manα1-2Manα1-2Man and Manα1-3Manα1-2Manα1-2Man possess domains corresponding to immunodominants of antigenic factors 1 and 34, respectively.
文摘To investigate the chemical structure of cell wall mannan obtained from pathogenic yeast, Candida tropicalis NBRC 1400 (former antigenic standard strain, IFO 1400). As a result of two-dimensional NMR analysis, it was shown that the mannan of this strain is composed of α-1,6-, α-1,3-, α-1,2- and β-1,2-linked mannose residues. In this research, the mannan was subjected to three degradation procedures, acid-treatment, α-mannosidase, and acetolysis under two conditions in order to determine the chemical structure of the antigenic oligomannosyl side chains in this molecule. The 1H-nuclear magnetic resonance spectra of resultant oligosaccharides, pentaose and hexaose, demonstrated the existence of the oligomannosyl side chains corresponding to Manα1-3Manα1-2Manα1-2Manα1-2Man and Manα1-3Manα1-2Manα1-2Manα1-2Manα1-2Man, respectively, which have previously also been found in Candida albicans serotype A strain mannans. These findings indicate that C. tropicalis and C. albicans serotype A have no significant difference in the chemical structure of these cell wall mannans. Therefore, it can be interpreted that it is extremely difficult to distinguish both species by targeting the antigenic group in these mannans.
文摘Sulfamic acid has been used as an efficient catalyst and green alternative for conventional acidic materials to promote the acetolysis reaction of THF to produce 1, 4-diacetoxybutane. This method is also applicable in the acetolysis of other cyclic ethers, such as methyl substituted THF and tetrahydropyran and 1,4-dioxane which is less reactivity.