Iron ions regulate antifungal HSAF biosynthesis in Lysobacter enzymogenes by manipulating the DNA-binding affinity of the ferric uptake regulator (Fur)

Microbiology Spectrum

卷:11

Research Article

Bao Tang^1,2  Bo Wang¹  Zhizhou Xu^1,3  Rouxian Hou^1,3  Min Zhang¹  Xian Chen¹  Youzhou Liu¹  Fengquan Liu^1,4 

[1] School of Life Sciences, Jiangsu University, Zhengjiang, Jiangsu, China

[2] Jiangsu Key Laboratory for Food Quality and Safety, State Key Laboratory Cultivation Base of Ministry of Science and Technology, Jiangsu Academy of Agricultural Sciences, Institute of Plant Protection, Nanjing, Jiangsu, China

[3] College of Plant Protection, Nanjing Agricultural University, Nanjing, Jiangsu, China

[4] College of Plant Protection, Hainan University, Haikou, China

关键词: Lysobacter enzymogenes;    biological pesticides;    ferric uptake regulator;    heat-stable antifungal factor;   

DOI  :  10.1128/spectrum.00617-23

 received in 2023-02-10, accepted in 2023-07-05,  发布年份 2023

来源: American Society for Microbiology

【 摘 要 】

ABSTRACTHeat-stable antifungal factor (HSAF), produced by Lysobacter enzymogenes OH11, is regarded as a potential biological pesticide due to its broad-spectrum antifungal activity and novel mode of action. However, the current production of HSAF is low and cannot meet the requirements for large-scale production. Herein, we discovered that iron ions greatly promoted HSAF production, and the ferric uptake regulator (Fur) was involved in this regulatory process. Fur was also found to participate in the regulation of iron homeostasis in OH11 via the classic inhibition mechanism of Holo-Fur. Furthermore, Fur was collectively observed to directly bind to the promoter of the HSAF biosynthesis gene, and its DNA-binding affinity was attenuated by the addition of iron ions in vitro and in vivo. Its regulatory mechanism followed the uncommon inhibition mechanism of Apo-Fur. In summary, Fur exhibited a bidirectional regulatory mechanism in OH11. This study reveals a novel regulatory mechanism whereby Fur upregulates the biosynthesis of secondary metabolites. These findings contribute to the improvement of HSAF production and may guide its development into biological pesticides.IMPORTANCEHSAF possesses potent and broad antifungal activity with a novel mode of action. The HSAF yield is critical for fermentation production. In this study, iron ions were found to increase HSAF production, and the specific mechanism was elaborated. These results provide theoretical support for genetic transformation to improve HSAF yield, supporting its development into biological pesticides.

【 授权许可】

CC BY   
Copyright © 2023 Tang et al.

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