ValC, a new type of C7-cyclitol kinase involved in the biosynthesis of the antifungal agent validamycin A
ValC, a new type of C7-cyclitol kinase involved in the biosynthesis of the antifungal agent validamycin A
复制标题
ValC 是一种新型 C7-环醇激酶，参与抗真菌剂井冈霉素 A 的生物合成。
DOI：
10.1002/cbic.200600528
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发表时间：
2007-04-16
期刊：
影响因子：
3.2
通讯作者：
Mahmud, Taifo
中科院分区：
文献类型：
--
作者：
Minagawa, Kazuyuki;Zhang, Yirong;Mahmud, Taifo
valC 基因编码与阿卡波糖生物合成途径的 2-epi-5-epi-valiolone 激酶 (AcbM) 同源的酶，在井冈霉素 A 生物合成基因簇中被鉴定。 valC 失活导致突变体缺乏产生井冈霉素 A 的能力。使用含有全长 valC 的复制质粒进行的互补实验恢复了井冈霉素 A 的产生，从而表明 valC 在井冈霉素生物合成中的关键功能。 ValC 的体外表征揭示了一种新型 C7-cyclitol 激酶，它磷酸化 valienone 和 validone（但不是 2-epi-5-epi-valiolone、5-epi-valiolone 或葡萄糖）以提供其 7-磷酸衍生物。这些结果为该酶的活性提供了新的见解，并证实了产生某些终产物的两种不同途径的存在：acorbose 和validamycin A 共有的volienamine 部分。
The gene valC, which encodes an enzyme homologous to the 2-epi-5-epi-valiolone kinase (AcbM) of the acarbose biosynthetic pathway, was identified in the validamycin A biosynthetic gene cluster. Inactivation of valC resulted in mutants that lack the ability to produce validamycin A. Complementation experiments with a replicating plasmid harboring full-length valC restored the production of validamycin A, thus suggesting a critical function of valC in validamycin biosynthesis. In vitro characterization of ValC revealed a new type of C7-cyclitol kinase, which phosphorylates valienone and validone-but not 2-epi-5-epi-valiolone, 5-epi-valiolone, or glucose-to afford their 7-phosphate derivatives. The results provide new insights into the activity of this enzyme and also confirm the existence of two different pathways leading to the some end-product: the volienamine moiety common to acorbose and validamycin A.