文献类型：期刊文献

中文题名：Study on a two-component signal transduction system RimA1A2 that negatively regulates oxytetracycline biosynthesis in Streptomyces rimosus M4018

作者：Hui Ni[1];Zhiqiang Xiong[2];Ali Mohsin[1];Meijin Guo[1];Hrvoje Petkovic[3];Ju Chu[1];Yingping Zhuang[1]

机构：[1]State Key Laboratory of Bioreactor Engineering,East China University of Science and Technology,P.O.box 329#,130 Meilong Rd,Shanghai,200237,People’s Republic of China;[2]Shanghai Engineering Research Center of Food Microbiology,School of Medical Instrument and Food Engineering,University of Shanghai for Science and Technology,Shanghai,200093,China;[3]Biotechnical Faculty,University of Ljubljana,Jamnikarjeva 101,1000,Ljubljana,Slovenia

年份：2019

卷号：6

期号：1

起止页码：578

中文期刊名：Bioresources and Bioprocessing

外文期刊名：生物资源与生物加工(英文)

基金：supported by the Fundamental Research Funds for the Central Universities(No.22221818014)to MG;This work as also supported by Slovenian Research Agency ARRS(Nos.J4-7637 and J4-8226)to HP.

语种：英文

中文关键词：RimA1A2;Oxytetracycline biosynthesis;Two-component regulatory system;Environmental stress;Streptomyces rimosus;Negative regulation

摘要：Biosynthesis of secondary metabolites in actinobacteria is regulated by complex regulatory mechanisms on responding environmental changes.In this study,we have identified a two-component system(TCS)designated as RimA1A2 in the genome of Streptomyces rimosus M4018,with high homology to the TCS RapA1A2 from Streptomyces coelicolor,known for its positive regulatory function towards actinorhodin(ACT)biosynthesis.Using RT-PCR analysis,we demonstrate that rimA1 encodes response regulator(RR)and rimA2 encoding histidine kinase(HK)from S.rimosus that are co-transcribed as a single-polycistronic mRNA.When S.rimosus was cultivated on standard media,no significant difference in culture growth or morphological properties was observed between the rimA1-disrupted mutant and parent strain M4018.However,the rimA1-disrupted strain displayed significant increase in oxytetracycline(OTC)titer when cultivated in minimal medium(MM)containing glycine as sole nitrogen source,and the transcription of selected genes involved in OTC biosynthesis was increased,supporting the hypothesis that RimA1A2 has a negative regulatory role in OTC biosynthesis via global regulation.We observed an increased resistance of the rimA1-disrupted mutant strain to selected antibiotics.Interestingly,in the rimA1-disrupted strain,OTC biosynthesis was affected under different environmental stress conditions such as osmotic and oxidative stress.Accordingly,this phenotype was observed in a medium-dependent manner.Considering complexity of regulatory networks in antibiotic-producing organisms,this study demonstrates the importance of cultivation conditions,which is often neglected.