MarR家族蛋白Orf17在自溶链霉菌格尔德霉素生物合成中的调控作用  

The regulatory role of MarR-family protein Orf17 in the biosynthesis of geldanamycin in Streptomyces autolyticus

作　　者：纪开燕[1] 杨玲 吴姣姣[1] 蒋明星[1] 韩秀林[1] 鲁涛[1] JI Kai-yan;YANG Ling;WU Jiao-jiao;JIANG Ming-xing;HAN Xiu-lin;LU Tao(Yunnan Institute of Microbiology,School of Life Sciences,Yunnan University,Kunming 650091,Yunnan,China)

机构地区：[1]云南大学生命科学学院,云南省微生物研究所,云南昆明650091

出　　处：《云南大学学报（自然科学版）》2021年第4期788-795,共8页Journal of Yunnan University(Natural Sciences Edition)

基　　金：国家自然科学基金(31260018);昆明学院引进人才科研项目(YJL18006).

摘　　要：格尔德霉素是自溶链霉菌产生的具有极强抗肿瘤活性的活性物质,但格尔德霉素生物合成的具体调控机制还不清楚.为了深入解析自溶链霉菌中格尔德霉素生物合成的调控机制,对其合成途径中一个MarR家族调控蛋白Orf17的功能及其调控作用进行了研究.HPLC分析显示,敲除了orf17基因的突变株中格尔德霉素的产量相比野生型降低,表明Orf17对格尔德霉素的生物合成起到了正调控作用;RT-PCR检测表明,在orf17突变株中与格尔德霉素合成相关的基因almAI、almF、almM、almH、almRⅠ、almRⅡ和almRⅢ的表达下降,表明这些基因的表达直接或间接地受到了Orf17的调控.进一步从orf17突变株中分离纯化出3个相比野生型产量升高的化合物,经鉴定为洋橄榄叶素及其衍生物.综上所述,Orf17在格尔德霉素生物合成中起到正调控作用,而对洋橄榄叶素的生物合成可能起到负调控作用.Geldanamycin,a bioactive compound produced by Streptomyces autolyticus,possesses potent antitumor activity.However,the specific regulatory mechanism of the biosynthesis of geldanamycin is yet unclear.To further illustrate the regulatory mechanism of geldanamycin biosynthesis in S.autolyticus,the function and regulatory mechanism of Orf17,a putative MarR family regulator were studied.The HPLC analysis of the fermentation products of the orf17 mutant showed that the production of geldanamycin in the orf17 mutant decreased when compared to that in the wild-type strains,suggesting that orf17 gene might play a positive role in the biosynthesis of geldanamycin.RT-PCR analysis revealed that the expression of genes almAⅠ,almF,almM,almH,almRⅠ,almRⅡ,and almRⅢ that are involved in the geldanamycin biosynthesis decreased in orf17 mutant,implying the expression of these genes was regulated by Orf17,directly or indirectly.Furthermore,three compounds with increased production in the mutant were purified and identified as elaiophylin and its analogues.In summary,Orf17 played a positive role in regulating the biosynthesis of geldanamycin,and a negative role in the biosynthesis of elaiophylin.

关 键 词：格尔德霉素 生物合成 Orf17调控蛋白 调控机制 

分 类 号：Q71[生物学—分子生物学]