JEFFERSON SHARED CIRCULAR DICHROISM FACILITY

杰斐逊共享圆二色性设施

• 批准号: 6053085
• 负责人: ERIC WICKSTROM
• 金额: $ 9.72万
• 依托单位: THOMAS JEFFERSON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-03-01 至 2001-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6053085
• 关键词: biomedical equipment purchase; circular dichroism

The circular dichroism of proteins and nucleic acids responds strongly to changes in secondary and tertiary structure, and allows initial assignment of unknown structures. Circular dichroic spectra may be measured on a microgram of sample, or less, depending on the sensitivity of the spectrometer. As a result, circular dichroic spectra permit the study of ligand binding to proteins and nucleic acids, and of protein/nucleic acid interactions, at physiological concentrations, using microgram quantities of purified samples. Similarly, model structures may be assigned to unknown macromolecules early in their analysis, before sufficient amounts of pure sample have been obtained for NMR spectroscopy or X- ray crystallography. Based on these capabilities, a sensitive, modern, and reliable circular dichroism spectrometer comprises a vital resource for determining the structure and function of proteins and nucleic acids. The core group of users at Jefferson proposes to replace the unreliable 15-year-old Jasco J-500 spectropolarimeter acquired by the PI under RR01554 with a modern, computer-controlled Jasco J-715 spectropolarimeter. The proposed new spectrometer can measure reliably down to 165 nm, rather than approximately 200 nm, with significantly greater signal-to-noise ratio. Peltier temperature control of multiple samples will allow temperature precision of +/-0.2 degrees, compared with circulating water bath control of single samples at +/-2.0 degrees. A modern computer interface will allow multiple scanning with wavelength precision of +/-0.2 nm, rather than +/-2.0 nm. A structural analysis package will permit facile analysis of spectra and deconvolution into structural components. With a modern spectrometer, the core users will be able to elucidate more rapidly the following questions. 1. How does the backbone of chimeric DNA and PNA derivatives control tetraplex formation by dGGGG motifs? 2. How do transposon Tn7 proteins recognize correct DNA sites for transposition? 3. How do unusual nucleic acid modifications alter the structure and properties of novel c-erbB-2 antisense therapeutics? 4. Do inactivating mutations in oncoproteins TCL-1 and MTCP-1 alter their structures? 5. How do proteoglycans reorganize collagen upon binding? 6. How do zinc finger proteins recognize specific RNA targets? 7. Do small peptide antagonists of receptors active in cancer, HIV infection and immunological diseases adopt structures mimicking the structures of the domains from which they were derived?

蛋白质和核酸的圆二色性对二级和三级结构的变化有强烈的响应，并允许未知结构的初始分配。圆二色性光谱可以在一微克或更少的样品上测量，这取决于光谱仪的灵敏度。因此，圆二色性光谱允许在生理浓度下使用微克量的纯化样品研究配体与蛋白质和核酸的结合以及蛋白质/核酸相互作用。类似地，在已经获得足够量的纯样品用于NMR光谱学或X射线晶体学之前，模型结构可以在其分析的早期被分配给未知的大分子。基于这些能力，灵敏、现代和可靠的圆二色谱光谱仪是确定蛋白质和核酸结构和功能的重要资源。Jefferson的核心用户组建议用现代化的计算机控制的Jasco J-715分光偏振仪取代PI根据RR 01554获得的不可靠的15岁Jasco J-500分光偏振仪。拟议的新光谱仪可以可靠地测量低至165 nm，而不是约200 nm，具有显着更大的信噪比。与单个样本的循环水浴控制+/-2.0度相比，多个样本的Peltier温度控制将允许+/-0.2度的温度精度。现代计算机接口将允许多个扫描，波长精度为+/-0.2 nm，而不是+/-2.0 nm。结构分析软件包将允许光谱的简易分析和结构组分的去卷积。有了现代化的光谱仪，核心用户将能够更快地阐明以下问题。1.嵌合DNA和PNA衍生物的骨架如何通过dGGGG基序控制四链体的形成？2.转座子Tn 7蛋白如何识别转座的正确DNA位点？3.不寻常的核酸修饰如何改变新型c-erbB-2反义疗法的结构和性质？4.癌蛋白TCL-1和MTCP-1的失活突变是否改变了它们的结构？5.蛋白多糖如何在结合后重组胶原蛋白？6.锌指蛋白如何识别特定的RNA靶点？7.在癌症、HIV感染和免疫性疾病中有活性的受体的小肽拮抗剂是否采用了模仿它们所来源的结构域的结构？

项目成果

Effects of hypoxanthine substitution in peptide nucleic acids targeting KRAS2 oncogenic mRNA molecules: theory and experiment.

• DOI: 10.1021/jp4064966
• 发表时间: 2013-10-03
• 期刊: The journal of physical chemistry. B
• 作者: Sanders JM;Wampole ME;Chen CP;Sethi D;Singh A;Dupradeau FY;Wang F;Gray BD;Thakur ML;Wickstrom E
• 通讯作者: Wickstrom E