FUNCTIONAL STUDIES OF ABNORMAL HEMOGLOBIN

本研究的长期目标是研究功能性 通过测量异常人血红蛋白的氧结合特性 在各种控制条件下的pH值，有机磷酸盐， 和其它离子条件。 结果将用于两个目的。 首先，将尝试将功能特性与 结构调整，以便更好地了解 血红蛋白中的特定氨基酸残基对其氧转运的影响 功能 第二，将试图解释是否存在 临床异常，如红细胞增多症或贫血， 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 用于分离免疫学上沉默的异常血红蛋白， 测量平衡反应中的氧血红蛋白。 2)屏幕 所有新的异常血红蛋白，因为他们成为 可用于O2结合的一般参数（P50，协同性，玻尔 效应和变构效应），以确定 改变的残基不影响正常的氧结合。 3)地审查 详细说明任何发现的异常血红蛋白， 使用自动记录系统的性能，该系统能够 估算氧化反应的四个Adair常数， 以尽可能精确地确定整个反应的哪一部分 氧气和血红蛋白的含量都被突变改变了 四、 将氧平衡反应的变化与改变的蛋白质相关联 结构，以便更好地理解正常的反应机制， 5)评估突变体的氧结合特性的变化程度 血红蛋白可以与其它血液学测量结果相关 红细胞2，3 DPG、红细胞压积和血红蛋白浓度。 所用的主要方法是测量氧平衡 曲线的自动记录系统的今井测量 同时血红蛋白和氧分压的功能饱和度 在小于1.0%饱和度至超过99.9%饱和度的范围内， 例血红蛋白A正常。 联机微机存储数据， 根据Adair分析结果的后续计算， 将采用其它反应模型进行解释。

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.