Circular dichroism spectrometer for analysis of protein structure and function

蛋白质的功能状态在很大程度上取决于它们的结构，大多数蛋白质在其功能周期过程中都会经历一系列的结构变化。蛋白质特性包括能够关联目标蛋白质的结构状态和功能状态。圆二色谱提供了一种强大而相对简单的工具来评估蛋白质的折叠状态，以及它是否在配体结合、酶周转或与蛋白质结合伙伴相互作用时发生了结构变化。圆二色谱(即CD)测量任何吸收光(即生色团)并具有某些固有结构不对称性的分子中心的固有光学活性。蛋白质分子在紫外可见光谱中具有生色团。在短紫外区，肽键本身吸收光，在近紫外区，如色氨酸等芳香族残基吸收光，在可见光和近红外区有假体基团，如血红素中心吸收光。这些生色团中的每一个都可能产生CD，并且信号的性质对生色团所处的环境很敏感。例如，当肽键处于a-螺旋等二级结构时，它的CD信号被修饰，而当它处于？折叠时，或者如果蛋白质是非结构的，则它是不同的。CD将用于区分我们的研究小组感兴趣的蛋白质的不同构象状态。了解蛋白质结构在其功能周期中的演变是能够预测、控制和调节蛋白质活性的关键组件。他们表示，这里所需的设备将为我们实验室的研究人员(学生、技术人员和博士后研究员)提供机会，利用现代蛋白质结构研究中最广泛使用的方法之一获得宝贵的培训。在这些领域改进对加拿大青年研究人员的培训是发展我们的基本科学和技术基础的一个重要因素。

The functional status of proteins is critically dependent on their structure and most proteins go through a series of structural changes in the course of their functional cycle. Protein characterization involves being able to correlate the protein of interest's structural status and its functional state. Circular dichroism spectroscopy provides a powerful and relatively simple tool to assess a protein for its folded state and whether or not it has undergone a structural change upon ligand binding, enzyme turnover, or interaction with a protein binding partner.     Circular dichroism (i.e., CD) spectroscopy measures the inherent optical activity of any molecular center that absorbs light (i.e., chromophore) and has some inherent structural asymmetry. Protein molecules possess chromophores across the UV-visible spectrum. In the short ultraviolet the peptide linkage itself absorbs light, in the near UV aromatic residues such as tryptophan absorb light and there are prosthetic groups such as heme centers that absorb light in the visible and near infrared regions. Each of these chromophores may give rise to CD, and the nature of the signal is sensitive to the environment in which the chromophore resides. For example, the CD signal of a peptide bond is modified when it is in a secondary structure such as an a-helix and it is different when in a ß-sheet, or if the protein is unstructured. CD will be used to distinguish different conformational states of proteins of interest to our research groups. Understanding the evolution of a protein's structure over its functional cycle is a critical component to being able to predict, control and regulate a protein's activity.       The equipment requested here will provide an opportunity for the research personnel in our laboratories (students, technicians and post-doctoral fellows) to gain valuable training with one of the most widely used approaches in modern protein structure studies. Improving the training of young Canadians researchers in these areas is an important element in the development of our fundamental science and technology base.