MECHANISM OF CYTOCHROME OXIDASE

SIR提供d-[1 N]氨基乙酰丙酸HC I; 7.07g L-[环_2] Hd酪氨酸; 0.5g D，L-[环- N2]组氨酸; 0.5g本项目的目的是 利用FTIR差谱法鉴别特定氨基酸 在质子泵的机制中起着重要作用， 血红素铜呼吸氧化酶 这是一个酶的大家族， 包括细胞色素氧化酶，它们利用 从氧气还原为水， 和跨生物膜的pH梯度。 的不同状态 在催化循环中作为重要中间体的酶可以 在实验室中产生，FTIR差谱可以 检测这些状态之间的差异。 手法十分 敏感，因此，质子化或去质子化的一个单一的氨基 蛋白质中的酸可以作为FTIR差异的变化来检测 江西篇章 确定蛋白质中的氨基酸 负责观察到的FTIR光谱变化需要使用 稳定同位素的结合。 质量变化 导致振动吸收带中可解释的位移 通过FTIR监测。 标记的组氨酸和酪氨酸已被 掺入细菌血红素-铜氧化酶，细胞色素B 0 3， E.杆菌 目前，我们正在研究纯化的酶， 同位素标记的氨基酸，使用FTIR光谱， 与集成光谱实验室的小组合作 在LANL。

The SIR provided d-["N]Aminolevulinic Acid.HC I; 7.07g L-[ring_2 HdTyrosine; 0.5g D,L-[ring- N2]Histidine; 0.5g The purpose of this project is to utilize FTIR difference spectroscopy to identify specific amino acids that have important roles in the mechanism of proton pumping of the heme-copper respiratory oxidases. This is a large family of enzymes, including cytochrome oxidase, that utilize the free energy made available from the reduction of dioxygen to water to make a voltage and pH gradients across the biological membrane. Different states of the enzyme that are important intermediates in the catalytic cycle can be generated in the laboratory, and FTIR difference spectroscopy can detect differences between these states. The technique is very sensitive, so that the protonation or deprotonation of a single amino acid in the protein can be detected as a change in the FTIR difference spectrum. Identifying the amino acids in the protein that are responsible for observed changes in the FTIR spectrum requires the use of stable isotopes incorporated in the enzyme. The change in mass results in interpretable shifts in the vibrational absorption bands monitored by FTIR. The labeled histidine and tyrosine have been incorporated into a bacterial heme-copper oxidase, cytochrome bo3 from E. coli. Currently, we are examining the purified enzymes containing the isotopically labeled amino acids using FTIR spectroscopy in collaboration with the group at the Integrated Spectroscopy Laboratory at LANL.