NMR & FTIR SPEAR OF SELECTIVELY LAB TYROSINE & ASPARTIC ACID HEMOGLOBIN

SIR提供L-天冬氨酸（4- 13 C），HOO* CCH_2CH（NH_2）COOH; 500 mg L-酪氨酸（苯酚-3，5-13 C），HOC 6 H4 CH 2CH（NH 2）COOH; 500 mg L-[RING-“C6]酪氨酸; 500 mg血红蛋白是一种a2/b2四聚体， 协同结合氧，进行结构重排， 过程 它在两种状态之间的变构转变已经被证明是 广泛接受，但血红蛋白行为的许多方面仍然存在 一个谜 在这些未知数中，有一个是玻尔的具体机制， 在酸性条件下促进氧气释放的作用。 该提案描述了同位素标记、NMR和 目的：探讨A. 特定的氢键，已被认为具有显着的 在血红蛋白的R到T转变中起作用，并可能有助于 玻尔效应。 Tyra 42和Asp b 99之间的氢键位于ALB 2 接口被认为是稳定的T状态的关键， 从几个试验田的数据。 基于紫外共振拉曼 未标记蛋白质的FIIR分析表明，Aspb 99可能是 氢键供体的对，因此，可能涉及玻尔效应。 对策略性标记的血红蛋白的实验应该允许精确的 H键的组成有待确定。 一旦确定这一点， 可以进行pH依赖性研究以研究 特定残留物对酸度变化的反应。 其他

The SIR provided L-Aspartic Acid (4- 13C) , HOO*CCH2CH(NH2)COOH; 500mg L-Tyrosine (phenol-3,5- 13C) , HOC6H4CH2CH(NH2)COOH; 500mg L-[RING-"C6]Tyrosine; 500mg Hemoglobin is an a2/b2 tetramer that cooperatively binds oxygen, undergoing a structural rearrangement in the process. Its allosteric transition between two states has been widely accepted, but many aspects of hemoglobin behavior still remain a mystery. Among the unknowns is the specific mechanism of the Bohr effect which promotes the release of oxygen under acidic conditions. This proposal describes the application of istopic labeling, NMR, and IR to investigate the biochemical significance and character of a specific hydrogen bond which has been suggested to have a significant role in the R to T transition in hemoglobin and may contribute to the Bohr effect. This H-bond between Tyra42 and Asp b99 at the alb2 interface is thought to be critical in stabilizing the T state based on data from several experimental fields. Based on UV resonance Raman and FIIR of unlabeled protein, it appears that Asp b99 may be the H-bond donor of the pair and thus, may be involved in the Bohr effect. Experiments on strategically labeled hemoglobin should allow the exact composition of the H-bond to be determined. Once this is determined, pH dependent studies could be conducted to investigate the behavior of specific residues in response to changes in acidity. Other