Genomic and Biocontrol Potential of the Crude Lipopeptide by Streptomyces bikiniensis HD-087 Against Magnaporthe oryzae

Abstract

Rice blast caused by Magnaporthe oryzae is one of the most destructive plant diseases. The secondary metabolites of Streptomyces have potential as biological control agents against M. oryzae. However, no commercial secondary antimicrobial products of Streptomyces have been found by gene prediction, and, particularly relevant for this study, a biocontrol agent obtained from Streptomyces bikiniensis has yet to be found. In this research, genomic analysis was used to predict the secondary metabolites of Streptomyces, and the ability to develop biocontrol pharmaceuticals rapidly was demonstrated. The complete genome of the S. bikiniensis HD-087 strain was sequenced and revealed a number of key functional gene clusters that contribute to the biosynthesis of active secondary metabolites. The crude extract of lipopeptides (CEL) predicted by NRPS gene clusters was extracted from the fermentation liquid of S. bikiniensis HD-087 by acid precipitation followed by methanol extraction, and surfactins, iturins, and fengycins were identified by liquid chromatography-mass spectrometry (LC–MS). In vitro, the CEL of this strain inhibited spore germination and appressorial formation of M. oryzae by destroying membrane integrity and through the leakage of cellular components. In vivo, this CEL reduced the disease index of rice blast by approximately 76.9% on detached leaves, whereas its control effect on leaf blast during pot experiments was approximately 60%. Thus, the S. bikiniensis CEL appears to be a highly suitable alternative to synthetic chemical fungicides for controlling M. oryzae.

Wheat Seed Coating with Streptomyces sp. Strain DEF39 Spores Protects against Fusarium Head Blight

“…Positive traits such as the resistance of Streptomyces spores to environmental stresses can lead to the development of novel strategies for the organic control and precision agriculture of important plant diseases such as FHB, limiting the interventions in the field [35]. Field studies to verify the fitness and efficacy of the strain in farming conditions as well as genomic studies to decipher the potential mode of action and the molecules involved in the bacteria-plant interaction [36] are warranted.…”

Transcriptome analysis of the production enhancement mechanism of antimicrobial lipopeptides of Streptomyces bikiniensis HD-087 by co-culture with Magnaporthe oryzae Guy11

“…Gauze’s synthetic broth medium No. 1 [ 20 ] was used for strain HD-087 activation, DBY medium [ 19 ] was used for HD-087 fermentation for lipopeptide production, and PDB medium [ 21 ] was used for Guy11 culture.…”

“…Our previous studies have shown that S. bikiniensis HD-087 has antioxidant activity against cucumber Fusarium wilt and F. oxysporum [ 17 ], and its metabolites contain lipopeptide, which significantly inhibit the growth of M. oryzae mycelium and reduce the disease index of M. oryzae ([ 18 , 19 ]. To improve the production of lipopeptides in HD-087, in this study, the co-culture of M. oryzae Guy11 and S. bikiniensis HD-087 enhanced the production of lipopeptides and produced a new peptide compared to pure culture.…”

Recent advances in the use of Trichoderma-containing multicomponent microbial inoculants for pathogen control and plant growth promotion

“…are crucial for their antifungal activities. Terpenes inhibit fungal growth (Adamczyk et al 2023 ) and pyrones interfere with spore germination and mycelial growth (Liu et al 2022a ; Degani and Gordan 2022 ). Others, such as gliotoxin and gliovirin, originally identified as antibiotic substances in some Trichoderma species, can induce oxidative stress and disrupt the intracellular redox homeostasis in fungal cells (Scharf et al 2016 ).…”