Colling Lisa, Carter Richard N, Essmann Michael, Larsen Bryan
Infectious Disease Research Laboratory, Des Moines University, IA 50312, USA.
Infect Dis Obstet Gynecol. 2005 Mar;13(1):43-8. doi: 10.1080/10647440400028169.
To develop an efficient method for evaluating cell surface hydrophobicity and to apply the method to demonstrate the effects of fungal growth conditions on cell surface properties.
Yeast isolates were suspended in phosphate-buffered saline and mixed with deep blue-dyed polystyrene microspheres. Flow cytometry was used to detect the degree of microsphere binding to yeast cells. Different strains of yeast were compared for intrinsic microsphere binding activity and changes in growth conditions were invoked to modify the relative surface hydrophobicity.
Commercially available blue-dyed polystyrene microspheres showed strong fluorescence in the FL3 channel, whereas yeast cells did not show appreciable FL3 fluorescence. Microspheres and yeast were generally distinguishable on the basis of size revealed by forward light scatter. This method showed a wide variation in intrinsic cell surface hydrophobicity among Candida albicans strains. Likewise, variation in hydrophobicity of non-albicans yeast species was observed. Growth on solid media, incubation at 25 degrees C, or 250 mg/dl glucose concentration increased hydrophobicity compared with growth in liquid media, incubation at 37 degrees C, or 50 mg/dl glucose, respectively. Growth in 1 x 10(-9) M estradiol had no appreciable effect on hydrophobicity.
Stained latex microspheres fluoresced in the FL3 channel of the flow cytometer and bound to yeast cells to an extent related to the surface hydrophobicity of the yeast. Binding detected by flow cytometry showed that clinical yeast isolates varied in intrinsic binding capacity and this binding ability was altered by different growth conditions. The implications for virulence regulation among yeast isolates are discussed.
开发一种评估细胞表面疏水性的有效方法，并应用该方法证明真菌生长条件对细胞表面特性的影响。
将酵母分离株悬浮于磷酸盐缓冲盐水中，并与深蓝色染色的聚苯乙烯微球混合。使用流式细胞术检测微球与酵母细胞的结合程度。比较不同酵母菌株的固有微球结合活性，并通过改变生长条件来改变相对表面疏水性。
市售的蓝色染色聚苯乙烯微球在FL3通道中显示出强烈的荧光，而酵母细胞未显示出明显的FL3荧光。根据前向光散射显示的大小，微球和酵母通常是可区分的。该方法显示白色念珠菌菌株之间的固有细胞表面疏水性存在很大差异。同样，观察到非白色念珠菌酵母种类的疏水性变化。与在液体培养基中生长、在37℃孵育或50mg/dl葡萄糖浓度下相比，在固体培养基上生长、在25℃孵育或250mg/dl葡萄糖浓度下生长分别增加了疏水性。在1×10(-9)M雌二醇中生长对疏水性没有明显影响。
染色的乳胶微球在流式细胞仪的FL3通道中发出荧光，并与酵母细胞结合，其结合程度与酵母的表面疏水性有关。通过流式细胞术检测到的结合表明，临床酵母分离株的固有结合能力不同，并且这种结合能力因不同的生长条件而改变。讨论了酵母分离株中致病性调节的意义。
