3-[(8R,13R)-18-(2-carboxylatoethyl)-8,13-bis(carboxylatomethyl)-3,8,13,17-tetramethyl-7,12-dioxoporphyrin-21,23-diid-2-yl]propanoate;iron(2+)

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 四吡咯及其衍生物
• 英文名称: 3-[(8R,13R)-18-(2-carboxylatoethyl)-8,13-bis(carboxylatomethyl)-3,8,13,17-tetramethyl-7,12-dioxoporphyrin-21,23-diid-2-yl]propanoate;iron(2+)
• 化学式: C34H28FeN4O10-4
• 分子量: 708.5
• InChiKey: XLQCGNUTSJTZNF-YDXXJHAFSA-H

计算性质

• 辛醇/水分配系数(LogP)：
  -1.69
• 重原子数：
  49
• 可旋转键数：
  6
• 环数：
  5.0
• sp3杂化的碳原子比例：
  0.35
• 拓扑面积：
  221
• 氢给体数：
  0
• 氢受体数：
  14

反应信息

• 作为反应物：
  描述：

  A 、 3-[(8R,13R)-18-(2-carboxylatoethyl)-8,13-bis(carboxylatomethyl)-3,8,13,17-tetramethyl-7,12-dioxoporphyrin-21,23-diid-2-yl]propanoate;iron(2+) 生成 AH₂ 、 Ferroheme d1(4-)
  参考文献：
  名称：

  分子劫持 siroheme 合成血红素和 d1 血红素。

  摘要：

  叶绿素、血红素、西罗血红素、维生素 B(12)、辅酶 F(430) 和血红素 d(1) 等改性四吡咯在生命的所有领域都具有广泛的基本生物学功能，因此令人惊讶的是其中许多生命色素仍然知之甚少。众所周知，修饰四吡咯的中心分子框架的构建是通过共同的核心途径介导的。在本文中，在反硝化和硫酸盐还原细菌以及古细菌中描述了修饰的四吡咯生物合成途径的另一个分支。这个过程需要劫持亚硫酸盐和亚硝酸盐还原酶的辅基 siroheme，并将其加工成血红素和 d(1) 血红素。这些转化的初始步骤包括将西罗血红素脱羧生成双脱羧基西罗血红素。对于 d(1) 血红素合成，该中间体必须用氧官能团替换两个丙酸侧链，并将双键引入另一个外围侧链。对于血红素合成，二脱羧基血红素通过两个乙酸侧链的氧化损失转化为 Fe-粪卟啉。Fe-粪卟啉然后通过两个丙酸侧链的氧化脱羧转化为血红素。讨论了这些反应的机制，并检查了西罗红素的另一个作用的进

  DOI：

  10.1073/pnas.1108228108

文献信息

• NirN Protein from Pseudomonas aeruginosa is a Novel Electron-bifurcating Dehydrogenase Catalyzing the Last Step of Heme d1 Biosynthesis
  作者：Julia Adamczack、Martin Hoffmann、Ulrich Papke、Kristin Haufschildt、Tristan Nicke、Martin Bröring、Murat Sezer、Rebecca Weimar、Uwe Kuhlmann、Peter Hildebrandt、Gunhild Layer

  DOI：10.1074/jbc.m114.603886

  日期：2014.10

  Heme d(1) plays an important role in denitrification as the essential cofactor of the cytochrome cd(1) nitrite reductase NirS. At present, the biosynthesis of heme d(1) is only partially understood. The last step of heme d(1) biosynthesis requires a so far unknown enzyme that catalyzes the introduction of a double bond into one of the propionate side chains of the tetrapyrrole yielding the corresponding acrylate side chain. In this study, we show that a Pseudomonas aeruginosa PAO1 strain lacking the NirN protein does not produce heme d(1). Instead, the NirS purified from this strain contains the heme d(1) precursor dihydro-heme d(1) lacking the acrylic double bond, as indicated by UV-visible absorption spectroscopy and resonance Raman spectroscopy. Furthermore, the dihydro-heme d(1) was extracted from purified NirS and characterized by UV-visible absorption spectroscopy and finally identified by high-resolution electrospray ionization mass spectrometry. Moreover, we show that purified NirN from P. aeruginosa binds the dihydro-heme d(1) and catalyzes the introduction of the acrylic double bond in vitro. Strikingly, NirN uses an electron bifurcation mechanism for the two-electron oxidation reaction, during which one electron ends up on its heme c cofactor and the second electron reduces the substrate/product from the ferric to the ferrous state. On the basis of our results, we propose novel roles for the proteins NirN and NirF during the biosynthesis of heme d(1).