ULTRASENSITIVE CALORIMETRY SYSTEM FOR BIOMOLECULES

建议为伊利诺伊大学芝加哥分校（UIC）购买一套完整的最先进的超灵敏微热测量系统，用于研究蛋白质-配体相互作用和蛋白质结构域的组织和稳定性。该设备由一个超灵敏等温滴定量热仪（ITC）单元和一个超灵敏差示扫描量热仪（DSC）单元组成。DSC装置将取代一个更老的装置，该装置的灵敏度只有替代装置的百分之一，而ITC装置则代表了该大学目前没有的新能力。这两种组件都代表了超灵敏量热计的最新技术，灵敏度和基线稳定性比上一代大大提高。这将使目前由于缺乏适当的仪器或足够的材料而无法解决的关键问题得到解答。这反过来又将大大提高利用该仪器进行研究的意义和竞争力。由于等温滴定量热法在一次滴定中提供了δ tah和δ tag值，因此也提供了δ tas，因此它给出了结合的完整热力学分析，因此比任何其他方法都要优越和直接得多。DSC提供了蛋白质稳定性、结构域组织和天然和未折叠状态下的热容量的信息。UIC的四个由美国国立卫生研究院资助的研究小组将是该设备的主要用户，并将共同使用80-90%的可用时间。这些是博士。医学院的盖金斯和廖博士。牙科学院的奥尔森和帕顿。剩余时间将提供给所有其他研究人员，优先考虑nih资助的研究人员。ITC或DSC将检查的系统包括(i)配体（包括伴侣蛋白RAP）与LDL受体相关蛋白（LRP）的结合，（ii）钙与LRP的配体结合结构域的结合，(iii) β -淀粉样肽与α - 2巨球蛋白的结合，（iv） LRP和LRP-蛋白配体复合物中的结构域-结构域相互作用，(v)钙缺失和存在时LRP结构域的稳定性，（vi）肝素与抗凝血酶变体的结合，（vii）抗凝血酶和其他蛇形蛋白与靶蛋白酶的相互作用，（viii）天然蛇形蛋白和裂解蛇形蛋白的稳定性，（viii）激素与甲状腺素结合球蛋白的结合，（ix） DNA与螺旋翼转录因子的结合，(x)涉及Ubll的蛋白-蛋白相互作用。

It is proposed to purchase a complete state-of-the-art ultrasensitive microcalorimetry system for the University of Illinois at Chicago (UIC), to be used for the study of protein-ligand interactions and protein domain organization and stability. The equipment consists of an ultrasensitive isothermal titration calorimetry (ITC) unit and an ultrasensitive differential scanning calorimetry (DSC) unit. The DSC unit will replace a much older unit that has only one hundredth the sensitivity of the replacement, while the ITC unit represents a new capability that is not presently available at the university. Both components represent the latest technology in ultrasensitive calorimeters, with sensitivities and baseline stabilities greatly improved over the previous generation. This will allow critical questions to be answered that can not currently be addressed for lack of appropriate instrumentation or sufficient material. This in turn will greatly enhance the significance and competitiveness of the research that will make use of the instrumentation. Since isothermal titration calorimetry provides, in a single titration, both deltaH and deltaG values, and hence deltaS as well, it gives a complete thermodynamic analysis of binding and is therefore greatly superior and more direct than any other approach. DSC provides information on protein stability, domain organization and heat capacity in native and unfolded states. Four NIH-funded research groups at UIC will be the primary users of the equipment and will together use 80-90% of available time. These are Drs. Gettins and Liao in the College of Medicine and Drs. Olson and Patston in the College of Dentistry. Remaining time will be available to all other investigators, with preference given to NIH-funded researchers at this institution. Systems that will be examined by ITC or DSC include (i) The binding of ligands, including the chaperone protein RAP, to the LDL receptor-related protein (LRP), (ii) calcium binding to ligand-binding domains of LRP, (iii) binding of beta-amyloid peptide to alpha2-macroglobulin, (iv) domain-domain interactions in LRP and in LRP-protein ligand complexes, (v) stability of LRP domains in the absence and presence of calcium, (vi) heparin binding to antithrombin variants, (vii) interaction of antithrombin and other serpins with target proteinases, (viii) stability of native and cleaved serpins, (viii) binding of hormone to thyroxine binding globulin, (ix) DNA binding to winged helix transcription factors, (x) protein-protein interactions involving Ubll.