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Assena MW, Pfannstiel J, Rasche F. Inhibitory activity of bacterial lipopeptides against Fusarium oxysporum f.sp. Strigae. BMC Microbiol 2024; 24:227. [PMID: 38937715 PMCID: PMC11212183 DOI: 10.1186/s12866-024-03386-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 06/18/2024] [Indexed: 06/29/2024] Open
Abstract
This study investigated the influence of bacterial cyclic lipopeptides (LP; surfactins, iturins, fengycins) on microbial interactions. The objective was to investigate whether the presence of bacteria inhibits fungal growth and whether this inhibition is due to the release of bacterial metabolites, particularly LP. Selected endophytic bacterial strains with known plant-growth promoting potential were cultured in the presence of Fusarium oxysporum f.sp. strigae (Fos), which was applied as model fungal organism. The extracellular metabolome of tested bacteria, with a focus on LP, was characterized, and the inhibitory effect of bacterial LP on fungal growth was investigated. The results showed that Bacillus velezensis GB03 and FZB42, as well as B. subtilis BSn5 exhibited the strongest antagonism against Fos. Paraburkholderia phytofirmans PsJN, on the other hand, tended to have a slight, though non-significant growth promotion effect. Crude LP from strains GB03 and FZB42 had the strongest inhibitory effect on Fos, with a significant inhibition of spore germination and damage of the hyphal structure. Liquid chromatography tandem mass spectrometry revealed the production of several variants of iturin, fengycin, and surfactin LP families from strains GB03, FZB42, and BSn5, with varying intensity. Using plate cultures, bacillomycin D fractions were detected in higher abundance in strains GB03, FZB42, and BSn5 in the presence of Fos. Additionally, the presence of Fos in dual plate culture triggered an increase in bacillomycin D production from the Bacillus strains. The study demonstrated the potent antagonistic effect of certain Bacillus strains (i.e., GB03, FZB42, BSn5) on Fos development. Our findings emphasize the crucial role of microbial interactions in shaping the co-existence of microbial assemblages.
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Affiliation(s)
- Mekuria Wolde Assena
- Institute of Agricultural Sciences in the Tropics (Hans-Ruthenberg-Institute), University of Hohenheim, Garbenstr. 13, 70599, Stuttgart, Germany
- Department of Horticulture, Wolkite University, Wolkite, Ethiopia
| | - Jens Pfannstiel
- Core Facility Hohenheim, Mass Spectrometry Unit, University of Hohenheim, Ottilie-Zeller- Weg 2, 70599, Stuttgart, Germany
| | - Frank Rasche
- Institute of Agricultural Sciences in the Tropics (Hans-Ruthenberg-Institute), University of Hohenheim, Garbenstr. 13, 70599, Stuttgart, Germany.
- International Institute of Tropical Agriculture, P.O. Box 30772-00100, Nairobi, Kenya.
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Cao CY, Hou ZJ, Ding MZ, Gao GR, Qiao B, Wei SY, Cheng JS. Integrated Biofilm Modification and Transcriptional Analysis for Improving Fengycin Production in Bacillus amyloliquefaciens. Probiotics Antimicrob Proteins 2024:10.1007/s12602-024-10266-8. [PMID: 38652228 DOI: 10.1007/s12602-024-10266-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/17/2024] [Indexed: 04/25/2024]
Abstract
Although fengycin exhibits broad-spectrum antifungal properties, its application is hindered due to its low biosynthesis level and the co-existence of iturin A and surfactin in Bacillus amyloliquefaciens HM618, a probiotic strain. In this study, transcriptome analysis and gene editing were used to explore the potential mechanisms regulating fengycin production in B. amyloliquefaciens. The fengycin level of B. amyloliquefacien HM-3 (∆itu-ΔsrfAA) was 88.41 mg/L after simultaneously inhibiting the biosyntheses of iturin A and surfactin. The knockout of gene eps associated with biofilm formation significantly increased the fengycin level of the strain HM618, whereas the fengycin level decreased 32.05% after knocking out sinI, a regulator of biofilm formation. Transcriptome analysis revealed that the differentially expressed genes, involved in pathways of amino acid and fatty acid syntheses, were significantly down-regulated in the recombinant strains, which is likely associated with a decrease of fengycin production. The knockout of gene comQXPA and subsequent transcriptome analysis revealed that the ComQXPA quorum sensing system played a positive regulatory role in fengycin production. Through targeted genetic modifications and fermentation optimization, the fengycin production of the engineered strain HM-12 (∆itu-ΔsrfAA-ΔyvbJ) in a 5-L fermenter reached 1.172 g/L, a 12.26-fold increase compared to the fengycin level in the strain HM-3 (∆itu-ΔsrfAA) in the Erlenmeyer flask. Taken together, these results reveal the underlying metabolic mechanisms associated with fengycin synthesis and provide a potential strategy for improving fengycin production in B. amyloliquefaciens.
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Affiliation(s)
- Chun-Yang Cao
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Yaguan Road 135, Tianjin, 300350, People's Republic of China
- Department of Pharmaceutical Engineering, School of Chemical Engineering and Technology, Tianjin University, Yaguan Road 135, Tianjin, 300350, People's Republic of China
| | - Zheng-Jie Hou
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Yaguan Road 135, Tianjin, 300350, People's Republic of China
- Department of Pharmaceutical Engineering, School of Chemical Engineering and Technology, Tianjin University, Yaguan Road 135, Tianjin, 300350, People's Republic of China
| | - Ming-Zhu Ding
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Yaguan Road 135, Tianjin, 300350, People's Republic of China
- Department of Pharmaceutical Engineering, School of Chemical Engineering and Technology, Tianjin University, Yaguan Road 135, Tianjin, 300350, People's Republic of China
| | - Geng-Rong Gao
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Yaguan Road 135, Tianjin, 300350, People's Republic of China
- Department of Pharmaceutical Engineering, School of Chemical Engineering and Technology, Tianjin University, Yaguan Road 135, Tianjin, 300350, People's Republic of China
| | - Bin Qiao
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Yaguan Road 135, Tianjin, 300350, People's Republic of China
| | - Si-Yu Wei
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Yaguan Road 135, Tianjin, 300350, People's Republic of China
- Department of Pharmaceutical Engineering, School of Chemical Engineering and Technology, Tianjin University, Yaguan Road 135, Tianjin, 300350, People's Republic of China
| | - Jing-Sheng Cheng
- Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Yaguan Road 135, Tianjin, 300350, People's Republic of China.
- Department of Pharmaceutical Engineering, School of Chemical Engineering and Technology, Tianjin University, Yaguan Road 135, Tianjin, 300350, People's Republic of China.
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Identification of Bacillus velezensis SBB and Its Antifungal Effects against Verticillium dahliae. J Fungi (Basel) 2022; 8:jof8101021. [PMID: 36294586 PMCID: PMC9604920 DOI: 10.3390/jof8101021] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 09/23/2022] [Accepted: 09/25/2022] [Indexed: 12/02/2022] Open
Abstract
Traditional control methods have drawbacks in controlling Verticillium wilt diseases caused by Verticillium dahliae Kleb.; therefore, an efficient and environmentally friendly strategy for disease control must be identified and the mechanisms determined. In this study, a soil-isolated strain SBB was identified as Bacillus velezensis based on 16S rRNA, gyrA, and gyrB gene sequences. In vitro, strain SBB had excellent inhibitory effects on V. dahliae, with the highest inhibition rate of 70.94%. Moreover, strain SBB inhibited production of the conidia of V. dahliae and suppressed the production of microsclerotia and melanin. Through gas chromatograph–mass spectrometer analysis, nine compounds were detected from the volatile organic compounds produced by SBB, among which 2-nonanol, 2-heptanone, 6-methyl-2-heptanone, and 2-nonanone could completely inhibit V. dahliae growth. Strain SBB produced cellulase, amylase, protease, and siderophore. During inhibitory action on V. dahliae, strain SBB showed upregulated expression of genes encoding non-volatile inhibitory metabolites, including difficidin, bacilysin, and bacillaene, at 1.923-, 1.848-, and 1.448-fold higher, respectively. Thus, our study proved that strain SBB had an efficient antagonistic effect on V. dahliae, suggesting strain SBB can be used as a potential biological control agent against Verticillium wilt.
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Gao XY, Xie W, Liu Y, Ma L, Liu ZP. Alcaligenes ammonioxydans HO-1 antagonizes Bacillus velezensis via hydroxylamine-triggered population response. Front Microbiol 2022; 13:920052. [PMID: 35935184 PMCID: PMC9355588 DOI: 10.3389/fmicb.2022.920052] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Accepted: 07/01/2022] [Indexed: 11/17/2022] Open
Abstract
Antagonism is a common behavior seen between microbes in nature. Alcaligenes ammonioxydans HO-1 converts ammonia to nitrogen under aerobic conditions, which leads to the accumulation of extracellular hydroxylamine (HA), providing pronounced growth advantages against many bacterial genera, including Bacillus velezensis V4. In contrast, a mutant variant of A. ammonioxydans, strain 2-29, that cannot produce HA fails to antagonize other bacteria. In this article, we demonstrate that cell-free supernatants derived from the antagonistic HO-1 strain were sufficient to reproduce the antagonistic behavior and the efficiency of this inhibition correlated strongly with the HA content of the supernatant. Furthermore, reintroducing the capacity to produce HA to the 2-29 strain or supplementing bacterial co-cultures with HA restored antagonistic behavior. The HA-mediated antagonism was dose-dependent and affected by the temperature, but not by pH. HA caused a decline in biomass, cell aggregation, and hydrolysis of the cell wall in exponentially growing B. velezensis bulk cultures. Analysis of differential gene expression identified a series of genes modulating multicellular behavior in B. velezensis. Genes involved in motility, chemotaxis, sporulation, polypeptide synthesis, and non-ribosomal peptide synthesis were all significantly downregulated in the presence of HA, whereas autolysis-related genes showed upregulation. Taken together, these findings indicate that HA affects the population response of coexisting strains and also suggest that A. ammonioxydans HO-1 antagonize other bacteria by producing extracellular HA that, in turn, acts as a signaling molecule.
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Affiliation(s)
- Xi-Yan Gao
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Wei Xie
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- College of Life Science, University of Chinese Academy of Sciences, Beijing, China
| | - Ying Liu
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Lan Ma
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- College of Life Science, University of Chinese Academy of Sciences, Beijing, China
| | - Zhi-Pei Liu
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
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