Biosynthesis of hibarimicins - II. Elucidation of biosynthetic pathway by cosynthesis using blocked mutants
Biosynthesis of hibarimicins - II. Elucidation of biosynthetic pathway by cosynthesis using blocked mutants
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DOI：
10.7164/antibiotics.55.53
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发表时间：
2002-01-01
影响因子：
3.3
通讯作者：
Oki, T
中科院分区：
文献类型：
--
作者：
Kajiura, T;Furumai, T;Oki, T
根据利用玫瑰微双孢菌阻断突变体获得的实验结果，提出了hibarimicin （HBM）的生物合成途径。HBM生产商hibararia TP-A0121。在其生物合成过程中，芳香烯醛酸单元的氧化偶联产生对称的糖基HMP-Y1 (hibarimicin-mutant product Y1)，该糖基被氧化修饰为hibarimicinone，即HBM糖基。hibarimicinone接下来的糖基化产生HBM复合物。我们发现HMP-Y6（来自阻断突变体的糖基化代谢物）的甲醇分解制备的HMP-Y1是关键的中间体：通过核磁共振测量证实了c -13标记的HMP-Y1向HBM B的转化。突变菌株产生了另一种类型的多糖HMP-P1，其中偶联的聚酮单元通过醚键在分子内桥接。该代谢物也由hibariminone中甲醇分子的自发消除而产生。
The biosynthetic pathway of hibarimicin (HBM) was proposed on the basis of the experimental results obtained by using blocked mutants of Microbispora rosea subsp. hibaria TP-A0121, the HBM producer. In its biosynthesis, the oxidative coupling of the aromatic undecaketide unit generates a symmetrical aglycon HMP-Y1 (hibarimicin-mutant product Y1), which is oxidatively modified to hibarimicinone, the HBM aglycon. The following glycosylation of hibarimicinone gives rise to the HBM complex. We identified that HMP-Y1 prepared by methanolysis of HMP-Y6, a glycosylated metabolite from a blocked mutant, was the key intermediate: transformation of C-13-labeled HMP-Y1 to HBM B was confirmed by NMR measurements. Mutant strain produced another type of aglycon HMP-P1 in which the coupled polyketide units were intramolecularly bridged by the ether bond. This metabolite also arose by the spontaneous elimination of methanol molecule from hibarimicinone.