FUNCTIONAL STUDIES OF ABNORMAL HUMAN HEMOGLOBINS

这项研究的长期目标是研究功能性 通过测定异常人血红蛋白的氧结合来研究其性质 在各种控制条件下的平衡，pH，有机磷酸盐， 和其他离子条件。结果将用于两个目的。 首先，我们将尝试将函数属性与 结构变化，以便更好地了解 血红蛋白中特定氨基酸残基对其氧转运的影响 功能。其次，将尝试解释是否存在 临床异常，如红细胞增多症或具有特异性的贫血 功能改变的异常血红蛋白。 具体目标包括：1)细化和完善程序和制度 用于分离电泳性沉默的异常血红蛋白和 平衡反应中氧-血红蛋白的测定。2)屏幕 以前没有研究过的和所有新的异常血红蛋白 适用于氧结合的一般参数(P50，协作性，玻尔 阴离子的效应和变构效应)，以便识别或 改变后的残基不会影响正常的氧结合。3)检查 详细说明任何发现的改变氧结合的异常血红蛋白 使用自动记录系统的物业，该系统能够 氧合反应四个Adair常数的有序估算 以尽可能准确地确定总体反应的哪一部分 氧气和血红蛋白的含量因突变而改变。4) 氧平衡反应的变化与蛋白质变化的相关性 结构，以便更好地了解正常的反应机理，以及 5)评估突变体氧结合特性的变化程度 血红蛋白可以与其他血液学指标相关联，例如 红细胞2，3DPG，红细胞压积和血红蛋白浓度。 使用的主要方法将是测量氧平衡。 由IMAAI自动记录系统测量的曲线 同时测定血红蛋白功能饱和度和氧分压 在低于1.0%的饱和度到99.9%以上的饱和度范围内 一例正常血红蛋白A的数据和微电脑在线存储 根据Adair分析和随后的结果计算 将使用其他反应模型进行解释。

The long-term objective of this research is to study the functional properties of abnormal human hemoglobins by measuring their oxygen binding equilibria under various controlled conditions of pH, organic phosphates, and other ion conditions. The results will be used for two purposes. First, attempts will be made to correlate functional properties with structural alterations in order to better understanding of contributions of specific amino acid residues in hemoglobin to its oxygen transport function. Second, attempts will be made to explain the presence or lack of clinical abnormalities such as erythrocytosis or anemia with specific abnormal hemoglobins with altered function. The specific aims include: 1) Refine and improve procedures and systems for isolating electrophoretically silent abnormal hemoglobins and for measuring oxygen-hemoglobin in the equilibrium reaction. 2) Screen previously unstudied and all new abnormal hemoglobins as they become available for general parameters of O2 binding (P50, cooperativity, Bohr effect and allosteric effects of anions) in order to identify whether or not the altered residue influences normal oxygen binding. 3) Examine in detail any abnormal hemoglobin found to have altered oxygen binding properties using an automatic recording system which is capable of estimating the four Adair constants for the oxygenation reaction in order to determine as precisely as possible which part of the over-all reaction of oxygen and hemoglobin has been altered by the mutational change. 4) Correlate changes in oxygen equilibrium reactions with altered protein structure in order to better understand the normal reaction mechanism, and 5) evaluate to what extent changes in oxygen binding properties of mutant hemoglobins can be correlated with other hematological measurements such as erythrocyte 2,3 DPG, hematocrit, and hemoglobin concentration. The principal method used will be the measurement of oxygen equilibrium curves by the automatic recording system of Imai which measures simultaneously the functional saturation of hemoglobin and oxygen pressure over a range of less than 1.0% saturation to over 99.9% saturation in the case of normal hemoglobin A. On-line microcomputer storage of data and subsequent computation of the results according to the Adair analysis and other reaction models will be employed for interpretation.