[methyl-¹⁴C]-S-adenosyl-L-methionine

• 分子结构分类: 有机化合物 - 核苷、核苷酸和类似物 - 5'-脱氧核糖核苷
• 英文名称: [methyl-¹⁴C]-S-adenosyl-L-methionine
• 英文别名: <(14)CH3>-S-adenosyl-L-methionine；S-[methyl-14C]adenosylmethionine；[(3S)-3-amino-3-carboxypropyl]-[[(2S,3S,4R,5R)-5-(6-aminopurin-9-yl)-3,4-dihydroxyoxolan-2-yl]methyl]-(114C)methylsulfanium
• 化学式: C₁₅H₂₃N₆O₅S
• 分子量: 401.44
• InChiKey: MEFKEPWMEQBLKI-JMJUVHIMSA-O

计算性质

• 辛醇/水分配系数(LogP)：
  -3.5
• 重原子数：
  27
• 可旋转键数：
  7
• 环数：
  3.0
• sp3杂化的碳原子比例：
  0.6
• 拓扑面积：
  184
• 氢给体数：
  5
• 氢受体数：
  10

反应信息

• 作为反应物：
  描述：

  coclaurine 、 [methyl-¹⁴C]-S-adenosyl-L-methionine 在 nicotinamide N-methyltransferase 作用下， 生成 (R,S)--N-methylcoclaurine
  参考文献：
  名称：

  The hydroxylation step in the biosynthetic pathway leading from norcoclaurine to reticuline

  摘要：

  DOI：

  10.1016/0031-9422(90)85264-g
• 作为试剂：
  描述：

  山奈酚 在 O-methyl transferase from cell-free extract of Citrus mitis 、 [methyl-¹⁴C]-S-adenosyl-L-methionine 、 2-巯基乙醇 作用下， 以 水 、 二甲基亚砜 为溶剂， 反应 0.5h， 生成 4-乙烯基氯苄 、 山奈素
  参考文献：
  名称：

  橙子无细胞提取物对黄酮类化合物的 O-甲基化

  摘要：

  摘要 柑桔（Citrus mitis）的无细胞提取物催化了许多类黄酮的几乎所有羟基的O-甲基化，表明柑橘组织中存在邻位、间位、对位和3-O-甲基转移酶。后者，迄今未报道的酶，催化高良姜素和槲皮素的 3-O-甲基醚的形成。许多化合物的逐步 O-甲基化，尤其是槲皮素和槲皮素，往往表明多酶复合物表面上存在协调的 O-甲基化序列。所使用的类黄酮底物的甲基受体能力与它们的羟基取代模式和它们的负电子密度分布有关。

  DOI：

  10.1016/0031-9422(80)85102-8

文献信息

• Capsinoid Is Biosynthesized from Phenylalanine and Valine in a Non-Pungent Pepper,<i>Capsicum annuum</i>L. cv. CH-19 Sweet
  作者：Kouzou SUTOH、Kenji KOBATA、Susumu YAZAWA、Tatsuo WATANABE

  DOI：10.1271/bbb.50665

  日期：2006.6.23

  The biosynthetic pathway of capsinoid in ‘CH-19 Sweet’ was investigated. [3H]Valine and [14C]phenylalanine were injected into the fruits of the intact plant. Both of radioactivities were detected in capsinoid fractions. 14C radioactivity was observed in phenylpropanoid compounds, and in vanillin, vanillylamine, vanillyl alcohol, and vanillic acid. We confirmed that capsinoid is biosynthesized from phenylalanine and valine.

  研究了'CH-19 甜'中辣椒碱的生物合成途径。将[3H]丙氨酸和[14C]苯丙氨酸注入完整植株的果实中。在蒴果苷馏分中检测到了这两种放射性物质。在苯丙类化合物、香兰素、香草醛、香草醇和香草酸中也观察到了 14C 放射性。我们证实蒴果苷是由苯丙氨酸和缬氨酸生物合成的。
• Purification and characterization of three isoforms of S-adenosyl-l-methionine: (R,S)-Tetrahydrobenzylisoquinoline-N-methyltransferase from Berberis koetineana cell cultures
  作者：Thomas Frenzel、Meinhart H. Zenk

  DOI：10.1016/0031-9422(90)85263-f

  日期：1990.1
• Catalytic specificity of pea O-methyltransferases suggests gene duplication for (+)-pisatin biosynthesis
  作者：Tomoyoshi Akashi、Hans D. VanEtten、Yuji Sawada、Catherine C. Wasmann、Hiroshi Uchiyama、Shin-ichi Ayabe

  DOI：10.1016/j.phytochem.2006.09.010

  日期：2006.12

  S-adenosyl-L-methionine: 2-hydroxyisoflavanone 4'-O-methyltransferase (HI4'OMT) methylates 2,7, 4'-trihydroxyisoflavanone to produce formononetin, an essential intermediate in the synthesis of isoflavonoids with methoxy or methylenedioxy groups at carbon 4' (isoflavone numbering). HI4'OMT is highly similar (83% amino acid identity) to (+)-6a-hydroxymaackiain 3-O-methyltransferase (HMM), which catalyzes the last step of (+)-pisatin biosynthesis in pea. Pea contains two linked copies of HMM with 96% amino acid identity. In this report, the catalytic activities of the licorice HI4'OMT protein and of extracts of Escherichia coli containing the pea HMM1 or HMM2 protein are compared on 2,7,4'-trihydroxyisoflavanone and enantiomers of 6a-hydroxymaackiain. All these enzymes produced radiolabelled 2,7-dihydroxy-4'-methoxyisoflavanone or (+)-pisatin from 2,7,4'-trihydroxyisoflavanone or (+)-6a-hydroxymaakiain when incubated with [methyl-C-14]-S-adenosyl-L-methionine. No product was detected when (-)-6a-hydroxymaackiain was used as the substrate. HIWOMT and HMMI showed efficiencies (relative V-max/K-m) for the methylation of 2,7,4'-trihydroxyisoflavanone 20 and 4 times higher than for the methylation of (+)-6a-hydroxymaackiain, respectively. In contrast, HMM2 had a higher V-max and lower K-m on (+)-6a-hydroxymaackiain, and had a 67-fold higher efficiency for the methylation of (+)-6a-hydroxymaackiain than that for 2,7,4'-trihydroxyisoflavanone. Among the 15 sites at which HMMI and HMM2 have different amino acid residues, 11 of the residues in HMM1 are the same as found in HI4'OMTs from three plant species. Modeling of the HMM proteins identified three or four putative active site residues responsible for their different substrate preferences. It is proposed that HMM I is the pea HIWOMT and that HMM2 evolved by the duplication of a gene encoding a general biosynthetic enzyme (HIWOMT). (c) 2006 Elsevier Ltd. All rights reserved.
• The hydroxylation step in the biosynthetic pathway leading from norcoclaurine to reticuline
  作者：Susanne Loeffler、Meinhart H. Zenk

  DOI：10.1016/0031-9422(90)85264-g

  日期：1990.1