磁场对酿酒酵母微观结构及膜脂流动性的影响  

Effect of Magnetic Field on Microscopic Structure and Cell Membrane Fluidity of Saccharomyces cerevisiae

作　　者：王山杉[1] 李琳[1] 李冰[1] 

机构地区：[1]华南理工大学轻工与食品学院,广东广州510640

出　　处：《华南理工大学学报（自然科学版）》2008年第4期138-143,共6页Journal of South China University of Technology(Natural Science Edition)

基　　金：国家自然科学基金重点项目(20436020);国家自然科学基金青年基金资助项目(20306007);广东省自然科学基金重点项目(04105934)

摘　　要：以磁场为外加物理场,采用恒定磁场及循环磁处理方式对酿酒酵母进行处理,研究酿酒酵母微观结构及细胞膜流动性的变化.通过透射电子显微镜观察不同磁感应强度恒定磁场处理后酿酒酵母的微观结构.研究发现恒定磁场可以促进酵母细胞的生长,群体中以具有中央大液泡为特征的成熟细胞所占比率增大,同时线粒体呈现适应性膨大、增生.利用原子力显微镜观察循环磁处理下酵母细胞的三维结构,发现细胞壁表面出现皱缩、穿孔,胞质外流.用荧光偏振法对两种处理方式下细胞的膜脂流动性进行测定,发现不同强度恒定磁场处理后,膜脂各向异性下降,流动性增强,0.05T磁感应强度下各向异性值下降3.57%,而循环磁处理后各向异性值比对照提高了8.46%,膜脂流动减慢,证实细胞膜为受到磁场作用的亚细胞结构.In order to reveal the changes in the microscopic structure and the cell membrane fluidity of Saccharomyces cerevisiae （S. cerervisiae） , magnetic fields were taken as the external physical fields to treat S. cerervisiae in two modes, namely, the static magnetic field （SMF） treatment and the magnetic cycling treatment. According to the TEM results of microscopic structure of the cells treated by SMF with different magnetic flux intensities, it is found that SMF stimulates the growth of S. cerevisiae cells, and that the ratio of mature cells with large central vacuoles in the colony increases. Swell and hyperplasia of mitochondria are also observed after the stimuli for their adaptability. From the atomic force microscopy （AFM） photographs that exhibit the 3D structures of yeast cells with magnetic cycling treatment, it is found that the surface of the cell wall wrinkles, the magnetoporation appears, and the cytosol leaks. The results of fluorescence polarization show that, after the SMF treatment at different magnetic flux intensities, the anisotropism of the cell membrane decreases while the membrane fluidity increases, and that the r-value decreases by 3.57% at 0.05T. However, after the magnetic cycling treatment, the r-value increases by 8.46% while the membrane fluidity decreases, which means that the cell membrane is a subcellular fraction influenced by magnetic fields.

关 键 词：磁场 酿酒酵母 微观结构 膜流动性 

分 类 号：Q64[生物学—生物物理学]