Department of Infection and Host Defense, Tohoku Pharmaceutical University, 4-4-1 Komatsushima, Aoba-ku, Sendai, Miyagi 981-8558, Japan.
Carbohydr Res. 2009 Nov 2;344(16):2195-200. doi: 10.1016/j.carres.2009.08.002. Epub 2009 Aug 8.
In this study, we investigated the structural changes in the cell wall mannan of Candida albicans serotype A strain cells cultured under various stress conditions, that is, oxidative stress of 3.5 mM H(2)O(2), osmotic stress of 1.5M NaCl, and heat stress at 37 degrees C, compared with the normal condition of 30 degrees C in yeast extract-added Sabouraud liquid medium (YSLM). Based on the (1)H nuclear magnetic resonance (NMR) and fluorophore-assisted carbohydrate electrophoresis (FACE) analyses of the mannans, we showed that the proportion of the terminal beta-1,2-linked mannose side chain unit in the mannan increased in the cell proliferation process under both the normal condition and the oxidative stress condition. The osmotic stress induced a slight decrease in the proportion of the beta-1,2-linked mannose unit in the acid-labile fraction. The heat stress induced a significant decrease in the proportions of the beta-1,2-linked mannose unit in both the acid-labile and acid-stable fractions. Based on these results, we propose that C. albicans significantly changes the mannan structures under various stress conditions and that sufficient attention to the cultural conditions is needed to perform an accurate diagnosis of candidiasis.
在这项研究中，我们研究了在不同应激条件下培养的白念珠菌 A 型菌株细胞细胞壁甘露聚糖的结构变化，即 3.5 mM H₂O₂的氧化应激、1.5 M NaCl 的渗透应激和 37°C 的热应激，与酵母提取物添加萨布罗琼脂液体培养基（YSLM）中的正常条件（30°C）相比。基于甘露聚糖的（1）H 核磁共振（NMR）和荧光辅助碳水化合物电泳（FACE）分析，我们表明在正常条件和氧化应激条件下，甘露聚糖中末端β-1,2-连接的甘露糖侧链单元的比例在细胞增殖过程中增加。渗透应激导致酸性不稳定部分中β-1,2-连接的甘露糖单元的比例略有下降。热应激导致酸性不稳定和稳定部分中β-1,2-连接的甘露糖单元的比例显著下降。基于这些结果，我们提出白念珠菌在各种应激条件下显著改变甘露聚糖结构，并且需要充分注意培养条件，以进行准确的念珠菌病诊断。
