摘要
为了研究腺苷三磷酸结合盒转运蛋白LmrC是否参与林可霉素的生物合成,通过同源重组在林可霉素高产菌株LC-G中构建了lmrC的缺失突变株XJJ7.高效液相色谱(HPLC)分析和抗性检测显示,相比出发菌株LC-G,XJJ7的林可霉素产量下降了55%,而且耐受林可霉素的最高质量浓度降低了50%.进一步实时荧光定量聚合酶链反应(PCR)分析发现,突变株XJJ7中林可霉素生物合成基因lmbA和lmbR的转录明显低于LC-G,但调控基因lmbU的转录不变.在LC-G中lmrC的过表达不能进一步提高产量,也不影响lmbA、lmbR和lmbU基因的转录,但过表达菌株对林可霉素的抗性显著增强.结果表明,lmrC可以通过影响生物合成基因的转录来调节林可霉素的产生,并赋予产生菌一定的抗性.
To investigate the role of lincomycin transporter LmrC in lincomycin biosynthesis, lmrC was deleted in a lincomycin high-yielding strain LC-G by homologous recombination. HPLC analysis and resistance assay indicated that lincomycin production and self-resistance in XJJ7, and the lmrC mutant were decreased by 55% and 500/00, respectively. Quantitative real-time polymerase chain reaction（PCR） analysis showed that the transcriptional levels of structure genes lmbA and lmbR were drastically reduced, whereas the expression of a regulatory gene lmbU did not change in XJJ7. Moreover, overexpression of lrnrC in LC- G could not increase the lincornycin yield and the expression of hnbA, lrnbR and lrnbU as well. However, the resistance to lincomycin was improved in the lrnrC-overexpressed strain. Therefore, lrnrC was proved to be involved in lincomycin biosynthesis by affecting the transcription of structure genes and confer linco mycin resistance to Streptomyces lincolnensis.
出处
《上海交通大学学报》
EI
CAS
CSCD
北大核心
2014年第2期159-163,共5页
Journal of Shanghai Jiaotong University
基金
国家自然科学基金(31300081)
安徽大学博士科研启动经费
微生物代谢国家重点实验室开放课题(MMLKF13-05)资助项目
关键词
林可链霉菌
林可霉素
腺苷三磷酸结合盒转运蛋白
抗性
Streptomyces lincolnensis
lincomycin
ATP-binding cassette （ABC） transporter
resistance
