Digitally Enhanced Microscope for Crystal Detection

描述(由申请人提供)：蛋白质的结构信息已被证明在药物的发现和开发中至关重要。膜蛋白，如离子通道和G蛋白偶联受体，构成了相当大一部分人类基因，并且是目前市场上大约60%的药物的靶标。膜蛋白三维结构的测定远远落后于可溶性蛋白质结构的测定。最近开发的一种膜蛋白晶体生长技术涉及使用由脂类立方相组成的结晶基质，膜蛋白在类似天然脂双层的微环境中结晶。到目前为止，使用这种方法只有有色膜蛋白被结晶。这在一定程度上是因为在原本无色的背景中很容易检测到有色晶体。虽然光学透明和非双折射，但在这些脂类中检测无色晶体是一个挑战。其原因在于晶体通常较小(有时不足50微米)，对比度较低，以及在结晶实验过程中可能发生的脂质相变造成的光学障碍。该项目的目标是开发一种基于显微镜的成像技术，以缓解这一限制。有人建议构建一种自动的、数字增强的交叉偏振显微镜来检测无色微晶。最终，这种数字对比度增强技术将允许在结晶试验中快速有效地检测非有色膜蛋白晶体。

DESCRIPTION (provided by applicant): Structural information of proteins have shown to be of critical importance in the discovery and development of pharmaceuticals. Membrane proteins such as ion channels and G-protein coupled receptors constitute a sizeable fraction of human genes and are targeted by approximately 60% of drugs that are currently on the market. Determinatinations of the 3-D structures of membrane proteins have lagged far behind the determination of structures of soluble proteins. A recently developed technique for membrane protein crystal growth involves the use of a crystallization matrix that consists of a lipidic cubic phase in which the membrane protein crystallizes in a microenvironment resembling native lipid bilayers. So far only colored membrane proteins have been crystallized using this method. This is partly due to the ease of detection of colored crystals in an otherwise colorless background. Though optically transparent and non-birefringent, the detection of non-colored crystals in these lipidic phases poses a challenge. The reason for this lies in the generally small size of crystals (sometimes less than 50 micrometers), in their low contrast and in optical obstructions caused by lipid phase transitions that may occur during the course of the crystallization experiment. The goal of this project is to develop a microscope-based imaging technology that alleviates this limitation. It is proposed to construct an automated, digitally enhanced cross-polarization microscope for the detection of colorless microcrystals. Ultimately this digital contrast enhancement technology will allow fast and efficient detection of non-colored membrane protein crystals in crystallization trials.