Physical properties of glycosyl diacylglycerols. 2. X-ray diffraction studies of a homologous series of 1,2-Di-O-acyl-3-O-(alpha-D-glucopyranosyl)-sn-glycerols.
Physical properties of glycosyl diacylglycerols. 2. X-ray diffraction studies of a homologous series of 1,2-Di-O-acyl-3-O-(alpha-D-glucopyranosyl)-sn-glycerols.
复制标题
糖基二酰基甘油的物理性质。
DOI：
10.1021/bi00486a004
复制
发表时间：
1990
期刊：
影响因子：
2.9
通讯作者：
McElhaney,RN
中科院分区：
文献类型：
--
作者：
Sen,A;Hui,SW;Mannock,DA;Lewis,RN;McElhaney,RN
材料和方法 X 射线衍射样品的制备。将冻干的脂质转移至1.5毫米玻璃毛细管中并添加水（脂质重量的四倍）。然后将毛细管中的内容物与不锈钢丝充分混合，用有机硅密封剂（陶氏化学公司，米德兰，密歇根州）密封，并在 85°C 和室温之间循环以确保样品完全水合。在进行 X 射线衍射测量之前，将样品离心以沉淀水合脂质，并在 DSC 检测到的各种相形成所需的条件下预孵育 [参见 Mannock 等人 (1990a)]。 X 射线衍射测量。衍射实验是使用在 40 kV 和 25 mA 下运行的旋转阳极 X 射线发生器（Rigaku Rotaflex，型号 RU-200B）和配备热电温控样品架的 Frank 型相机进行的。用胶片（柯达，X 射线胶片 DEF-5）和位置敏感正比计数器（TEC Model 25，诺克斯维尔，田纳西州）记录衍射图案。该计数器与装有脉冲高度分析仪附加板的 IBM PCAT 个人计算机相连。典型的衍射测量涉及胶片记录的 2-3 小时曝光和计数器的 15-30 分钟曝光。使用 Joyce-Loebl 密度计测量胶片上记录的条带强度。
Materials and MethodsPreparation of Samples for X-ray Diffraction. The lyo-philized lipids were transferred to 1.5-mm glass capillaries and water (four times the weight of the lipids) was added. The contents of the capillaries were then thoroughly mixed with a stainless steel wire, sealed with a silicone sealant (Dow Chemicals Corp., Midland, MI), and cycled between 85 C and room temperature to ensure full hydration of the samples. Prior to the X-ray diffraction measurements, the samples were centrifuged to pellet the hydrated lipids and preincubated under the conditions needed for the formation of the various phases detected by DSC [see Mannock et al.(1990a)]. X-ray Diffraction Measurements. The diffraction experiments were performed with a rotating-anode X-ray generator (Rigaku Rotaflex, Model RU-200B) operating at 40 kV and 25 mA and a Frank’s-type camera fitted with a thermoelectric temperature-controlled sample holder. Diffraction patterns were recorded with film (Kodak, X-ray film DEF-5) and with a position-sensitive proportional counter (TEC Model 25, Knoxville, TN). The counter was interfaced to an IBM PCAT personal computer fitted with a pulse height analyzer add-on board. Typical diffraction measurements involved 2-3-h exposures for film recordings and 15-30-min exposures for thecounter. A Joyce-Loebl densitometer was used for the measurement of the intensities of the bands recorded on film.