波赛链霉菌dnrK基因中断突变株代谢产物鉴定

Identification of the metabolite produced by dnrK-disrupted Streptomyces peucetius

目的鉴定波赛链霉菌HS062(柔红霉素工业菌株)dnr K基因中断突变株新次级代谢产物。方法将dnr K基因中插入了阿泊拉霉素抗性基因及"海正"标记片段的中断载体p BSSP-KA导入波赛链霉菌HS062,筛选获得dnr K插入失活的突变株DK55,通过HPLC-MS和NMR对DK55菌株产生的新代谢产物进行结构鉴定。结果 dnr K中断突变株DK55产生了一个新的蒽环类代谢产物,该化合物经结构鉴定为histomodulin,并且其效价远远高于原产物柔红霉素。结论本研究通过基因工程手段获得高产histomodulin菌株,为该化合物的应用研究打下了基础;同时,探讨了工业菌株中dnr K基因敲除后菌株代谢产物变化原因,为进一步提高柔红霉素及其衍生物的产量提供了新的思路。

Objective To identify the new secondary metabolites from the dnrK gene disrupted strain of Streptomyces peucetius. Methods The gene disruption vector was constructed by inserting a 1.6-kb fragment containing apramycin resistance gene and Hisun Marker sequence into the BamHI site. The vector was introduced into an industrial daunorubicin-producing strain, Streptomyces peucetius HS062. The novel product from the double cross-over strain DK55 was analyzed by HPLC-MS and NMR. Results The new compound produced by the mutant strain DK55 was identified as histomodulin by IH-NMR and 13C-NMR analysis. The yield of histomodulin was more than 2 fold higher than that of daunorubicin in the original strain HS062. Conclusion The high yield histomodulin producing strain derived via genetic engineering paved the way for the future study in the field of antineoplasmic activity. In addition, present data provide an insight for improving the yields of daunorubicin as well as the derivatives in the industrial strain HS062.