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

Abstract

The lipopeptides produced by Streptomyces bikiniensis have a significant inhibitory effect on Magnaporthe oryzae, but the low yield limits its application. In this study, the anti-M. oryzae activity of the broth of S. bikiniensis HD-087 co-cultured with M. oryzae Guy11 mycelium has risen by 41.22% compared with pure culture, and under induction conditions of adding Guy11-inducer (cell-free supernatant of M. oryzae Guy11), the activity of strain HD-087 improved 61.76%. The result proved that the enhancement effect of Guy11 on the antimicrobial activity of HD-087 was mainly related to metabolites but mycelium cells. Under optimum induction conditions, NRPS gene expression levels of HD-087 were significantly increased by induction with Guy11-inducer, the biomass of HD-087 had no significant change, but crude extract of lipopeptide (CEL) production was 107.4% higher than pure culture, and TLC result under acid hydrolysis showed that the induced culture has one component more than pure culture. To clarify the regulation mechanism of improving lipopeptide production of HD-087 with Guy11-inducer, transcriptomic analysis was performed using RNAseq to compare the induced culture and pure culture. In the induced culture, 943 genes were up-regulated, while 590 genes were down-regulated in DEGs (differentially expressed genes). KEGG results showed that the expression of genes related to amino acid synthesis, fatty acid metabolism, TCA cycle and pyruvate metabolism pathway were significantly increased. The increased expression of genes related to these metabolic pathways provided sufficient precursors for lipopeptide synthesis. Accordingly, key enzyme genes responsible for the synthesis of lipopeptides Srf and NRPS was significantly increased. Quorum sensing related genes OppA and MppA were significantly up-regulated, and then ComP was activated and promoted lipopeptide synthesis. These results provided a scientific basis for using M. oryzae to induce the increase of the production of Streptomyces lipopeptides, and also laid a foundation for further exploring the co-culture mechanisms among different genera.

Interactions between plant‐beneficial microorganisms in a consortium: Streptomyces microflavus and Trichoderma harzianum

“…In the Trichoderma ‐ Botrytis interaction, sesquiterpenes produced by the pathogen triggered the production of polyketides by T. arundinaceum (Malmierca et al, 2015 ) and polyketides produced by Botrytis cinerea induced the expression of genes involved in sesquiterpene biosynthesis in T. arundinaceum (Malmierca et al, 2016 ). Similarly, in the Streptomyces ‐ Magnaporthe interaction, NRPS gene expression levels and lipopeptide production of S. bikiniensis were significantly augmented in vitro in the presence of M. oryzae (Liu et al, 2022 ).…”

Enhancement of polymyxin B1 production by an artificial microbial consortium of Paenibacillus polymyxa and recombinant Corynebacterium glutamicum producing precursor amino acids

“…When lipopeptide production was enhanced by co-culture or the exogenous addition of nutrients, transcriptome analysis revealed overexpression of genes related to precursor metabolic pathways, which is closely involved in the up-regulated of key enzyme genes responsible for lipopeptide synthesis, and NRPS [ 36 , 37 ]. Particularly, quorum sensing-related genes oppA and mppA had significant up-regulation, and then activated ComP to promote lipopeptide synthesis [ 37 ].…”

Influence of Biological Inductors on the Synthesis and Biological Activity of Microbial Metabolites

“…There is limited information in the literature regarding the impact of supernatant after cultivation of biological inductors on the synthesis and antimicrobial activity of secondary metabolites. Most of the research focuses on the induction of bacteriocin synthesis [4], pigments [24], surfactants [25], antibiotics [21,22,[26][27][28], and other secondary metabolites [29].…”

“…Surfactants. The authors in the study [25] reported a 107.4% increase in In the study [32], it was found that the introduction of live B. subtilis BT-2 cells into the R. erythropolis culture medium with ethanol (2%, v/v) was accompanied by the synthesis of surfactants that were characterized by higher antimicrobial activity than surfactants synthesized in the medium without inductor. The minimum inhibitory concentrations against testcultures of these biosurfactants were 6 μg/ml, which were 8 times lower than the values established for the preparations obtained without the inductor.…”

“…3) the supernatant (filtrate) after cultivation of a competitive microorganism is used as an inductor [4,21,22,[24][25][26][27][28][29].…”