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量热计系统，用于研究蛋白质-配体相互作用以及蛋白质结构域的组织和稳定性。该装置由超灵敏等温滴定量热仪(ITC)和超灵敏差示扫描量热仪(DSC)组成。DSC单元将取代一个更老的单元，其灵敏度只有替换单元的百分之一，而ITC单元代表着该大学目前无法提供的一种新能力。这两种组件都代表了超灵敏量热仪的最新技术，其灵敏度和基线稳定性比上一代产品有了很大提高。这将使目前由于缺乏适当的工具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将利用该仪器进行的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deltaH和deltaG值，因此也提供了deltaG值，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更优越和更直接。DSC提供了蛋白质在天然和未折叠状态下的稳定性、结构域组织和热容量的信息。UIC的四个由NIH资助的研究小组将是该设备的主要用户，总共将使用80%-90%的可用时间。这些是医学院的Gettins和廖医生，以及牙科学院的Olson和Patston医生。剩余的时间将提供给所有其他研究人员，优先考虑NIH资助的该机构的研究人员。将由ITC或DSC检查的系统包括(I)包括伴侣蛋白RAP的配体与低密度脂蛋白受体相关蛋白(LRP)的结合，(Ii)与LRP的配体结合结构域的结合，(Iii)β-淀粉样肽与α2-巨球蛋白的结合，(Iv)LRP和LRP-蛋白质配基复合体中的结构域-结构域相互作用，(V)LRP结构域在无钙和存在下的稳定性，(Vi)肝素与抗凝血酶变体的结合，(Vii)抗凝血酶和其他丝氨酸与靶蛋白酶的相互作用，()原生和卵裂蛇类的稳定性，()激素与甲状腺激素结合球蛋白的结合，(Ix)脱氧核糖核酸与有翼螺旋转录因子的结合，(X)涉及Ubl1的蛋白质-蛋白质相互作用。

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.