解淀粉芽孢杆菌中非编码RNA FenS对丰原素合成酶基因表达调控的研究

丰原素是一类由解淀粉芽孢杆菌代谢产生，对丝状真菌具有显著抑菌活性的生物源抗菌肽，在食品防腐等领域具有潜在的应用价值。目前，丰原素产量较低，国内外对丰原素合成的分子调控机理不甚了解，由非编码RNA参与的基因转录后调控更是未见报道。由于缺乏对丰原素合成酶基因表达调控机制的了解，限制了研究人员在分子水平上改造菌株，提高丰原素产量的可行性。针对这一科学问题，本项目以解淀粉芽孢杆菌为研究菌株，对非编码RNA FenS参与丰原素合成酶基因的转录后调控机制进行探讨。通过敲除和过表达与丰原素合成酶基因存在靶向调控关系的非编码RNA FenS，探索FenS对丰原素合成的影响；结合蛋白组学分析及定点突变技术，分析FenS调控fengycin合成的分子机理，为从分子水平上改造解淀粉芽孢杆菌，提高丰原素产量提供理论依据，同时为生物源食品防腐剂的工业化利用奠定基础。

Fengycin，as a antimicrobial peptide, is produced by Bacillus spp and displays potent antifungal activity against filamentous fungi. Therefore, it exhibits potential application in food preservation and other fields. At present, the production of Fengycin is quite low through fermentation, and the molecular mechanism of fengycin synthesis is still unclear; furthermore, the study about non-coding RNA involved in the post transcriptional regulation of genes has not been reported. Therefore, the feasibility of genetic modification in strain to increase fengycin production is limited due to the lack of the information involved in expression and regulation mechanism of fengycin synthetase gene. In view of this scientific issue, Bacillus amyloliquefaciens is taken as a research object, and the mechanism of interaction between non-coding RNA FenS and gene of fengycin synthetase is going to be investigated in this project. The investigation of the effect of FenS on fengycin synthesis will be performed through knockout and overexpression of FenS gene which is targeting regulatory relations with fengycin synthase gene. Furthermore, the proteomic analysis and site directed mutagenesis will be used to investigate the fengycin synthesis mechanism regulated by sRNA. As a result, the theoretical basis is to be provided for improving fengycin yield by genetic modification of Bacillus amyloliquefaciens.