(+)-7-Isojasmonate

• 分子结构分类: 有机化合物 - 脂质和类脂质分子 - 脂肪酰基
• 英文名称: (+)-7-Isojasmonate
• 英文别名: 2-[(1R,2S)-3-oxo-2-[(Z)-pent-2-enyl]cyclopentyl]acetate
• 化学式: C12H17O3-
• 分子量: 209.26
• InChiKey: ZNJFBWYDHIGLCU-QKMQQOOLSA-M

计算性质

• 辛醇/水分配系数(LogP)：
  2.2
• 重原子数：
  15
• 可旋转键数：
  4
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.67
• 拓扑面积：
  57.2
• 氢给体数：
  0
• 氢受体数：
  3

反应信息

• 作为反应物：
  描述：

  (+)-7-Isojasmonate 、 adenosine 5'-triphosphate 、 L-异亮氨酸 生成 adenosine 5'-monophosphate 、 pyrophosphoric acid 、 氢(+1)阳离子 、 (+)-7-iso-JA-L-Ile
  参考文献：
  名称：

  The Oxylipin Signal Jasmonic Acid Is Activated by an Enzyme That Conjugates It to Isoleucine in Arabidopsis[W]

  摘要：

  尽管茉莉酸（JA）在多种植物防御反应中很重要，但我们对其在生化水平上的功能的理解有限。测试了几种JA的氨基酸结合物，以评估它们是否能够补充JA不敏感的拟南芥突变体jar1-1。与游离的JA不同，JA-Ile在jar1-1中抑制根生长的程度与野生型相同，而JA-Val、JA-Leu和JA-Phe在两种基因型中均无效。通过薄层色谱和气相色谱-质谱（GC-MS）分析，重组JAR1在体外产生的产物表明，该酶与几种氨基酸形成JA酰胺结合物，包括JA-Ile。通过GC-MS在拟南芥幼苗中量化了JA-Val、-Leu、-Ile和-Phe。在野生型中，JA-Ile在每克鲜重（FW）中的含量为29.6皮摩尔，但在两个jar1等位基因中降低了七倍以上。在两种基因型中，JA-Leu、-Val和-Phe的含量都很低。在转基因jar1-1植物中表达野生型JAR1可恢复对JA的敏感性，并将JA-Ile提升到与野生型相同的水平。在植物组织中，乙烯前体1-氨基环丙烷-1-羧酸（ACC）结合到JA的含量为18.4皮摩尔/g FW。JA-ACC被确定为不是有效的茉莉酸根抑制剂，并且令人惊讶的是，在突变体中的含量是野生型的两倍。这表明在拟南芥中存在另一种JA结合酶。JA-ACC的合成可能提供了一种机制，用于共调节JA和ACC的可用性，以转化为活性激素JA-Ile和乙烯。我们得出结论，JAR1是一种JA-氨基合成酶，在拟南芥中需要激活JA以实现最佳信号传递。以氨基酸结合物激活植物激素和参与其形成的酶以前是未知的。

  DOI：

  10.1105/tpc.104.023549
• 作为产物：
  描述：

  水 、 (+)-7-iso-JA-L-Ile 生成 (+)-7-Isojasmonate 、 L-异亮氨酸
  参考文献：
  名称：

  The Amidohydrolases IAR3 and ILL6 Contribute to Jasmonoyl-Isoleucine Hormone Turnover and Generate 12-Hydroxyjasmonic Acid Upon Wounding in Arabidopsis Leaves

  摘要：

  Jasmonates (JAs) are a class of signaling compounds that mediate complex developmental and adaptative responses in plants. JAs derive from jasmonic acid (JA) through various enzymatic modifications, including conjugation to amino acids or oxidation, yielding an array of derivatives. The main hormonal signal, jasmonoyl-L-isoleucine (JA-Ile), has been found recently to undergo catabolic inactivation by cytochrome P450-mediated oxidation. We characterize here two amidohydrolases, IAR3 and ILL6, that define a second pathway for JA-Ile turnover during the wound response in Arabidopsis leaves. Biochemical and genetic evidence indicates that these two enzymes cleave the JA-Ile signal, but act also on the 12OH-JA-Ile conjugate. We also show that unexpectedly, the abundant accumulation of tuberonic acid (12OH-JA) after wounding originates partly through a sequential pathway involving (i) conjugation of JA to Ile, (ii) oxidation of the JA-Ile conjugate, and (iii) cleavage under the action of the amidohydrolases. The coordinated actions of oxidative and hydrolytic branches in the jasmonate pathway highlight novel mechanisms of JA-Ile hormone turnover and redefine the dynamic metabolic grid of jasmonate conversion in the wound response.

  DOI：

  10.1074/jbc.m113.499228

文献信息

• The Amidohydrolases IAR3 and ILL6 Contribute to Jasmonoyl-Isoleucine Hormone Turnover and Generate 12-Hydroxyjasmonic Acid Upon Wounding in Arabidopsis Leaves
  作者：Emilie Widemann、Laurence Miesch、Raphaël Lugan、Emilie Holder、Clément Heinrich、Yann Aubert、Michel Miesch、Franck Pinot、Thierry Heitz

  DOI：10.1074/jbc.m113.499228

  日期：2013.11

  Jasmonates (JAs) are a class of signaling compounds that mediate complex developmental and adaptative responses in plants. JAs derive from jasmonic acid (JA) through various enzymatic modifications, including conjugation to amino acids or oxidation, yielding an array of derivatives. The main hormonal signal, jasmonoyl-L-isoleucine (JA-Ile), has been found recently to undergo catabolic inactivation by cytochrome P450-mediated oxidation. We characterize here two amidohydrolases, IAR3 and ILL6, that define a second pathway for JA-Ile turnover during the wound response in Arabidopsis leaves. Biochemical and genetic evidence indicates that these two enzymes cleave the JA-Ile signal, but act also on the 12OH-JA-Ile conjugate. We also show that unexpectedly, the abundant accumulation of tuberonic acid (12OH-JA) after wounding originates partly through a sequential pathway involving (i) conjugation of JA to Ile, (ii) oxidation of the JA-Ile conjugate, and (iii) cleavage under the action of the amidohydrolases. The coordinated actions of oxidative and hydrolytic branches in the jasmonate pathway highlight novel mechanisms of JA-Ile hormone turnover and redefine the dynamic metabolic grid of jasmonate conversion in the wound response.
• The Oxylipin Signal Jasmonic Acid Is Activated by an Enzyme That Conjugates It to Isoleucine in Arabidopsis[W]
  作者：Paul E. Staswick、Iskender Tiryaki

  DOI：10.1105/tpc.104.023549

  日期：2004.8.4

  Despite its importance in a variety of plant defense responses, our understanding of how jasmonic acid (JA) functions at the biochemical level is limited. Several amino acid conjugates of JA were tested for their ability to complement the JA-insensitive Arabidopsis thaliana mutant jar1-1. Unlike free JA, JA-Ile inhibited root growth in jar1-1 to the same extent as in the wild type, whereas JA-Val, JA-Leu, and JA-Phe were ineffective inhibitors in both genotypes. Thin-layer chromatography and gas chromatography–mass spectrometry (GC-MS) analysis of products produced in vitro by recombinant JAR1 demonstrated that this enzyme forms JA-amido conjugates with several amino acids, including JA-Ile. JA-Val, -Leu, -Ile, and -Phe were each quantified in Arabidopsis seedlings by GC-MS. JA-Ile was found at 29.6 pmole g−1 fresh weight (FW) in the wild type but was more than sevenfold lower in two jar1 alleles. JA-Leu, -Val, and -Phe were present at only low levels in both genotypes. Expression of wild-type JAR1 in transgenic jar1-1 plants restored sensitivity to JA and elevated JA-Ile to the same level as in the wild type. The ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC) conjugated to JA was also found in plant tissue at 18.4 pmole g−1 FW. JA-ACC was determined not be an effective jasmonate root inhibitor, and surprisingly, was twofold higher in the mutants than in the wild type. This suggests that another JA-conjugating enzyme(s) is present in Arabidopsis. Synthesis of JA-ACC might provide a mechanism to coregulate the availability of JA and ACC for conversion to the active hormones JA-Ile and ethylene, respectively. We conclude that JAR1 is a JA-amino synthetase that is required to activate JA for optimal signaling in Arabidopsis. Plant hormone activation by conjugation to amino acids and the enzymes involved in their formation were previously unknown.

  尽管茉莉酸（JA）在多种植物防御反应中很重要，但我们对其在生化水平上的功能的理解有限。测试了几种JA的氨基酸结合物，以评估它们是否能够补充JA不敏感的拟南芥突变体jar1-1。与游离的JA不同，JA-Ile在jar1-1中抑制根生长的程度与野生型相同，而JA-Val、JA-Leu和JA-Phe在两种基因型中均无效。通过薄层色谱和气相色谱-质谱（GC-MS）分析，重组JAR1在体外产生的产物表明，该酶与几种氨基酸形成JA酰胺结合物，包括JA-Ile。通过GC-MS在拟南芥幼苗中量化了JA-Val、-Leu、-Ile和-Phe。在野生型中，JA-Ile在每克鲜重（FW）中的含量为29.6皮摩尔，但在两个jar1等位基因中降低了七倍以上。在两种基因型中，JA-Leu、-Val和-Phe的含量都很低。在转基因jar1-1植物中表达野生型JAR1可恢复对JA的敏感性，并将JA-Ile提升到与野生型相同的水平。在植物组织中，乙烯前体1-氨基环丙烷-1-羧酸（ACC）结合到JA的含量为18.4皮摩尔/g FW。JA-ACC被确定为不是有效的茉莉酸根抑制剂，并且令人惊讶的是，在突变体中的含量是野生型的两倍。这表明在拟南芥中存在另一种JA结合酶。JA-ACC的合成可能提供了一种机制，用于共调节JA和ACC的可用性，以转化为活性激素JA-Ile和乙烯。我们得出结论，JAR1是一种JA-氨基合成酶，在拟南芥中需要激活JA以实现最佳信号传递。以氨基酸结合物激活植物激素和参与其形成的酶以前是未知的。