Microscope for crystallization trials

我们的实验室感兴趣的是了解细菌如何使用蛋白质来吸收必要和稀缺的营养铁。例如，病原菌需要铁才能在受感染的宿主中生存。如果这些细菌不能从环境中获得足够的铁，它们就会挨饿。为了获得铁，细菌制造称为铁载体的分子，这些分子被分泌到环境中以清除铁。在细菌E.Coli中已经确定了大约12种蛋白质，它们是合成和分泌铁载体所必需的。我们的研究涉及这些蛋白质的特征以及它们如何相互作用。我们认为，他们的行动是以网络状的安排进行协调的，以确保有效地合成和分泌铁载体。我们将描述与铁载体生物合成和分泌有关的蛋白质的三维结构。要做到这一点，我们将提纯蛋白质，并试图使它们结晶。然后，我们可以通过测量X射线如何被晶体衍射来使用X射线来确定蛋白质的结构。由于蛋白质晶体非常小(通常为10-500微米)，我们需要使用强大的显微镜来监控实验室中晶体的生长。我们还需要一种设备，使光在晶体中平面偏振，因为蛋白质晶体在偏振光照射下会变色。这将使我们能够评估我们的蛋白质晶体的质量。最后，数字照片记录系统将使我们能够监测结晶试验的进展。

Our laboratory is interested in learning how bacteria use proteins to uptake the essential and scarce nutrient iron. Pathogenic bacteria, for example, require iron for survival in infected hosts. If these bacteria cannot obtain enough iron from their environment, they will starve. To obtain iron, bacteria make molecules called siderophores, which are secreted into the environment to scavenge iron. About a dozen proteins have been identified in the bacterium E. coli as being necessary to synthesize and secrete siderophores. Our research involves characterizing these proteins and how they interact with each other. We believe that their action is coordinated in a network-like arrangement to make sure that siderophores are efficiently synthesized and secreted. We will characterize the three-dimensional structures of proteins involved in siderophore biosynthesis and secretion. To do this, we will purify the proteins and attempt to crystallize them. We can then use X-rays to determine the structures of the proteins by measuring how the X-rays are diffracted by the crystal. Since protein crystals are very small (generally 10-500 microns in size), we need to use a powerful microscope to monitor the growth of our crystals in the laboratory. We also need a device that will plane-polarize light through the crystal since protein crystals change colour when exposed to polarized light. This will allow us to assess the qualities of our protein crystals. Finally, a digital photodocumentation system will allow us to monitor the progress of our crystallization trials.