文献类型： 外文期刊

作者： Dong, Dan ¹ ; Li, Maoying ² ; Zhang, Taotao ¹ ; Niu, Zhenfeng ¹ ; Xue, Guoping ³ ; Bai, Hongmei ³ ; Zhao, Wenyu ¹ ; Yu, Jiajia ¹ ; Jiang, Wei ³ ; Wu, Huiling ¹ ;

作者机构： 1.Beijing Acad Agr & Forestry Sci, Key Lab Environm Friendly Management Fruit & Veget, Coconstruct Minist & Prov, Inst Plant Protect,Minist Agr & Rural Affairs, Beijing 100097, Peoples R China

2.Beijing Acad Agr & Forestry Sci, Natl Watermelon & Melon Improvement Ctr, Beijing 100097, Peoples R China

3.Inner Mongolia Acad Agr & Anim Husb Sci, Hohhot 010031, Peoples R China

关键词： biological control; Streptomyces alfalfae; differentially expressed genes; secondary metabolites; RNA-seq

期刊名称：PLANTS-BASEL （ 影响因子：4.5； 五年影响因子：4.8 ）

ISSN：

年卷期： 2023 年 12 卷 22 期

页码：

收录情况： SCI

摘要： Streptomyces alfalfa strain 11F has inhibitory effects on many phytopathogenic fungi and improves the establishment and biomass yield of switchgrass. However, the antagonistic effects of strain 11F on Fusarium wilt of watermelon and its secondary metabolites that contribute to its biocontrol activity are poorly understood. We evaluated the antagonistic and growth-promoting effects of strain 11F and conducted a transcriptome analysis to identify the metabolites contributing to antifungal activity. Strain 11F had marked inhibitory effects on six fungal pathogens. The incidence of Fusarium wilt of watermelon seedlings was decreased by 46.02%, while watermelon seedling growth was promoted, as indicated by plant height (8.7%), fresh weight (23.1%), and dry weight (60.0%). Clean RNA-sequencing data were annotated with 7553 functional genes. The 2582 differentially expressed genes (DEGs) detected in the Control vs. Case 2 comparison were divided into 42 subcategories of the biological process, cellular component, and molecular function Gene Ontology categories. Seven hundred and forty functional genes (55.47% of the DEGs) were assigned to Kyoto Encyclopedia of Genes and Genomes metabolic pathways, reflecting the complexity of the strain 11F metabolic regulatory system. The expression level of the gene phzF, which encodes an enzyme essential for phenazine-1-carboxylic acid (PCA) synthesis, was downregulated 3.7-fold between the 24 h and 48 h fermentation time points, suggesting that strain 11F can produce phenazine compounds. A phenazine compound from 11F was isolated and identified as phenazine-1-carboxamide (PCN), which contributed to the antagonistic activity against Fusarium oxysporum f. sp. niveum. PCA was speculated to be the synthetic precursor of PCN. The downregulation in phzF expression might be associated with the decrease in PCA accumulation and the increase in PCN synthesis in strain 11F from 24 to 48 h. Streptomyces alfalfae 11F protects watermelon seedlings from Fusarium wilt of watermelon and promotes seedling growth. The transcriptome analysis of strain 11F provides insights into the synthesis of PCN, which has antifungal activity against F. oxysporum f. sp. niveum of watermelon.