Machado M Cecilia, López Claudia S, Heras Horacio, Rivas Emilio A
Instituto de Biología Celular y Neurociencias "Dr. E De Robertis," Facultad de Medicina Universidad de Buenos Aires, Paraguay 2155, Buenos Aires, Argentina.
Arch Biochem Biophys. 2004 Feb 1;422(1):61-70. doi: 10.1016/j.abb.2003.11.001.
The biochemical and biophysical properties of the membrane and some general characteristics of the response of Lactobacillus casei ATCC 393 (reclassified Lactobacillus zeae) to hyperosmotic conditions were studied. Under hypertonic conditions, the hydrophobicity and the bile salt sensitivity of the cultures were increased. The glycolipid AcylH3DG is only present in membranes of NaCl containing medium, whereas, H4DG undergoes a significant increment and H2DG a significant decrease. The fluidity of both the purified membranes and the total lipid vesicles, as determined with the fluorescent probe DPH, did not change in conditions of high salinity. This was coincident with changes in the fatty acid (FA) composition where an increase in the saturated/unsaturated FA ratio was compensated by a rise in the fluidifying 11,12-methyleneoctadecanoic FA (cyc 19:0). Under osmotic stress conditions, Laurdan and acridine orange in total lipid vesicles showed increased lateral lipid packing and proton permeability, respectively.
研究了干酪乳杆菌ATCC 393（重新分类为玉米乳杆菌）细胞膜的生化和生物物理特性以及其对高渗条件的一些一般响应特征。在高渗条件下，培养物的疏水性和胆盐敏感性增加。糖脂酰基H3DG仅存在于含NaCl培养基的细胞膜中，而H4DG显著增加，H2DG显著减少。用荧光探针DPH测定的纯化细胞膜和总脂质囊泡的流动性在高盐度条件下没有变化。这与脂肪酸（FA）组成的变化一致，其中饱和/不饱和FA比率的增加被流动性增强的11,12-亚甲基十八烷酸FA（环19:0）的增加所补偿。在渗透胁迫条件下，总脂质囊泡中的劳丹和吖啶橙分别显示出侧向脂质堆积增加和质子渗透性增加。
