herboxidiene

• 分子结构分类: 有机化合物 - 脂质和类脂质分子 - 异戊烯醇脂质
• 英文名称: herboxidiene
• 英文别名: 2-[(2R,5S,6S)-6-[(6S)-7-[(2R,3R)-3-[(2R,3R,4R)-4-hydroxy-3-methoxypentan-2-yl]-2-methyloxiran-2-yl]-6-methylhepta-2,4-dien-2-yl]-5-methyloxan-2-yl]acetic acid
• 化学式: C₂₅H₄₂O₆
• 分子量: 438.605
• InChiKey: ISZXEMUWHQLLTC-OSLOXCKMSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  4.36
• 重原子数：
  31.0
• 可旋转键数：
  11.0
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.8
• 拓扑面积：
  88.52
• 氢给体数：
  2.0
• 氢受体数：
  5.0

反应信息

• 作为产物：
  描述：

  18-deoxy-25-demethylherboxidiene 、 S-腺苷-L-蛋氨酸 在 cytochrome P₄₅₀ hydroxylase 、 spinach ferredoxin–NADP reductase 、 还原型辅酶II(NADPH)四钠盐 、 spinach ferredoxin 作用下， 以 aq. buffer 为溶剂， 生成 herboxidiene 、 18-deoxyherboxidiene
  参考文献：
  名称：

  A specific cytochrome P450 hydroxylase in herboxidiene biosynthesis

  摘要：

  The anti-cholesterol natural product herboxidiene is synthesized by a noniterative modular polyketide synthase (HerB, HerC and HerD) and three tailoring enzymes (HerE, HerF and HerG) in Streptomyces chromofuscus A7847. In this work, the putative monooxygenase HerG was expressed in Escherichia coli and the purified enzyme was subjected to biochemical studies. It was identified as a cytochrome P450 enzyme responsible for the stereospecific hydroxylation at C-18. This enzyme is highly substrate-specific as it efficiently hydroxylates 18-deoxy-25-demethyl-herboxidiene, but showed no activity towards 18-deoxy-herboxidiene. The k(cat)/K-m value for the HerG-catalyzed hydroxylation of 18-deoxy-25-demethyl-herboxidiene was determined to be 1669.70 +/- 47.36 M-1 s(-1). In vitro co-reaction of HerG with the methyltransferase HerF and analysis of the product formation in S. chromofuscus A7847 revealed that the biosynthetic intermediate 18-deoxy-25-demethyl-herboxidiene is successively hydroxylated at C-18 by HerG and methylated at 17-OH to yield the final product herboxidiene. The minor metabolite 18-deoxy-hereboxidiene is a byproduct of the biosynthetic pathway. (C) 2014 Elsevier Ltd. All rights reserved.

  DOI：

  10.1016/j.bmcl.2014.07.078