ASSESSING THE CORE STRUCTURE OF A STABLE PEROXO DIIRON INTERMEDIATE IN THE AMINE

评估胺中稳定的过氧化二铁中间体的核心结构

• 批准号: 8170246
• 负责人: MICHAEL T. GREEN
• 金额: $ 0.27万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-05-01 至 2011-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8170246
• 关键词: 4-Aminobenzoic Acid; Acids; Amines; Antibiotics; Biochemical; Biological; Charge; Computer Retrieval of Information on Scientific Projects Database; Electrons; Enzymes; Exhibits; Funding; Grant; Heme Iron; Institution; Iron; Isomerism; Kinetics; Methane hydroxylase; Optics; Oxygenases; Peroxides; Reaction; Research; Research Personnel; Resources; Source; Structure; Techniques; United States National Institutes of Health; aureothin; member; novel; oxidation

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. AurF, a novel oxygenase from S. thioluteus, catalyzes the unusual 6-electron oxidation of p- aminobenzoic acid (pABA) to p-nitrobenzoic acid (pNBA), an essential structural component of the antibiotic aureothin. We have demonstrated that AurF is a member of dinuclear non-heme- iron enzymes that are involved in numerous biological oxidation reactions (e.g. soluble methane monooxygenase). Using a combination of biochemical, kinetic, and spectroscopic techniques, we have identified a chemically competent peroxo-diiron(III/III) intermediate in this reaction. In the absence of substrate, pABA, this intermediate accumulates to nearly stoichiometric amounts, but it readily oxidizes the substrate. The peroxo-diiron(III/III) intermediate has markedly different spectroscopic parameters compared to other, well characterized peroxo-diiron(III/III) that are believed to have a ?-1,2-peroxo unit. Its optical transition (possibly a peroxide-to-iron charge transfer band) is observed around 500 nm, and it has a M¿ssbauer isomer shift of beta = 0.50 mm/s. ?-1,2-Peroxo-diiron(III/III) intermediates exhibit M¿ssbauer isomer shifts beta > 0.60 mm/s and a LMCT band at ~700 nm.

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 AuRF是一种新的S. thioluteus催化对氨基苯甲酸（pABA）不寻常的6电子氧化为对硝基苯甲酸（pNBA），对硝基苯甲酸是抗生素金噻吩的基本结构组分。 我们已经证明，AURF是双核非血红素铁酶的成员，参与许多生物氧化反应（如可溶性甲烷单加氧酶）。 使用生物化学，动力学和光谱技术相结合，我们已经确定了化学主管过氧二铁（III/III）在这个反应中的中间体。 在没有底物pABA的情况下，该中间体积累到接近化学计量的量，但它容易氧化底物。过氧二铁（III/III）中间体与其他充分表征的过氧二铁（III/III）相比具有明显不同的光谱参数，这些过氧二铁（III/III）被认为具有？1，2-过氧单元。 它的光学跃迁（可能是过氧化物到铁的电荷转移带）在500 nm附近观察到，它的穆斯堡尔同质异能素位移β = 0.50 mm/s。?- 1，2-过氧二铁（III/III）中间体显示穆斯堡尔异构体位移β> 0.60 mm/s，LMCT带在~700 nm处。