Tsuboi R, Komatsuzaki H, Ogawa H
Department of Dermatology, Juntendo University School of Medicine, Tokyo, Japan.
Infect Immun. 1996 Aug;64(8):2936-40. doi: 10.1128/iai.64.8.2936-2940.1996.
An extracellular esterase from Candida albicans A-714 was found to be induced in a medium containing 0.7% yeast nitrogen base and 2.5% Tween 80 (polyoxyethylenesorbitan compounds). Enzyme activity, which exists predominantly in the extracellular space, was measured by a colorimetric method using alpha-naphthyl palmitate as a substrate. The induction level of the esterase activity was found to be well correlated with fungal growth and was dependent on the Tween 80 concentration. Such esterase activity was observed only in medium containing Tween 80 or other Tweens as the sole carbon source and therefore was not observed in either peptone-glucose medium or peptone-glucose medium supplemented with Tween 80. The induced esterase was heat labile and had maximum activity at pH 5.5. Enzyme activity was stimulated by the addition of sodium taurocholate, an activator of lipase. Thin-layer chromatography revealed that this enzyme does not hydrolyze triolein and L-alpha-lecithin, suggesting that it is a monoester hydrolase (not a lipase in the strict sense of the word). Esterase activity was examined in 85 clinical isolates of Candida species; C. albicans, C. tropicalis, and C. parapsilosis tended to have higher enzyme activities than C. kefyr, C. krusei, C. glabrata, and C. guilliermondii. Although the physiological properties of this esterase are not clear at present, it was found to be crucial for fungal growth under specific conditions.
白色念珠菌A - 714的一种细胞外酯酶在含有0.7%酵母氮源和2.5%吐温80（聚氧乙烯山梨糖醇酐化合物）的培养基中被诱导产生。主要存在于细胞外空间的酶活性，通过以α - 萘基棕榈酸酯为底物的比色法进行测定。发现酯酶活性的诱导水平与真菌生长密切相关，并且取决于吐温80的浓度。这种酯酶活性仅在以吐温80或其他吐温作为唯一碳源的培养基中观察到，因此在蛋白胨 - 葡萄糖培养基或添加了吐温80的蛋白胨 - 葡萄糖培养基中均未观察到。诱导产生的酯酶对热不稳定，在pH 5.5时具有最大活性。通过添加牛磺胆酸钠（一种脂肪酶激活剂）可刺激酶活性。薄层色谱显示该酶不水解三油酸甘油酯和L-α-卵磷脂，表明它是一种单酯水解酶（严格意义上不是脂肪酶）。对85株念珠菌临床分离株的酯酶活性进行了检测；白色念珠菌、热带念珠菌和近平滑念珠菌的酶活性往往高于克柔念珠菌、克鲁斯念珠菌、光滑念珠菌和季也蒙念珠菌。尽管目前这种酯酶的生理特性尚不清楚，但发现它在特定条件下对真菌生长至关重要。
