A simple and inexpensive nanoliter-volume dispenser for highly viscous materials used in membrane protein crystallization
A simple and inexpensive nanoliter-volume dispenser for highly viscous materials used in membrane protein crystallization
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DOI：
10.1007/s0021889805001640
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发表时间：
2005-04-01
影响因子：
6.1
通讯作者：
Caffrey, M
中科院分区：
文献类型：
--
作者：
Cherezov, V;Caffrey, M
高分子结晶试验涉及大量化学和环境条件的测试。对于每一种，都需要一定量的蛋白质和沉淀剂。在膜蛋白的情况下，洗涤剂和脂质必须包括在筛选中，这增加了所进行的试验的数量。除了极少数的例外，膜蛋白是非常珍贵的。因此，迫切需要缩小筛选过程，以便最有效地利用这些稀缺材料。脂质和清洁剂也可能非常昂贵，小型化也有好处。最近，引入了通过内消旋方法使膜蛋白结晶的玻璃板系统[Cherezov & Caffrey（2003）. J.Appl.Cryst.36，1372 - 1377; Caffrey（2003）. J. Struct.Biol.142，108 - 132]。该方案要求处理小体积的非常粘稠的淀粉/蛋白质分散体。一个积极的位移基于的工具，实现了这些耐火材料混合物的制备和分配。然而，该装置由商业部件组装而成，使用微升大小的样品操作，并且在输送量方面不像它那样经济。为了实现进一步的小型化，从而节省材料，分配器已经以便于用手准确和精确地重复输送纳升体积的液体和高粘度分散体的方式进行了修改。这里描述了可以简单且廉价地对商业上可获得的部件进行的修改以及新配置的分配器的性能特征，其中所述修改沿着
Macromolecular crystallization trials involve the testing of large numbers of chemical and environmental conditions. For each, a certain amount of protein and precipitant is required. In the case of membrane proteins, detergent and lipids must be included in the screen, which adds to the number of trials performed. With rare exceptions, membrane proteins come at a premium. Thus, there is a pressing need to scale down the screening process so as to make most efficient use of these scarce materials. Lipids and detergents can also be very expensive and miniaturization is of benefit here too. Recently, a glass-plate system for crystallizing membrane proteins by the in meso method was introduced [Cherezov & Caffrey ( 2003). J. Appl. Cryst. 36, 1372 - 1377; Caffrey ( 2003). J. Struct. Biol. 142, 108 - 132]. The protocol calls for the handling of small volumes of lipidic/ protein dispersions that are extraordinarily viscous. A positive-displacement syringe-based tool was implemented for the preparation and dispensing of these refractory mixtures. However, the device, assembled from commercial parts, operated with microliter-sized samples and was not as economical as it could be in terms of delivered volumes. To effect further miniaturization, and thus conservation of materials, the dispenser has been modified in a way that facilitates accurate and precise repetitive delivery by hand of nanoliter volumes of liquids and of highly viscous dispersions. Here the modifications, which can be made simply and inexpensively to commercially available parts, along with the performance characteristics of the newly configured dispenser, are described