Scholarlink

<p>Foodborne pathogenic microorganisms and the escalating crisis of antibiotic resistance present significant threats to global public health and food safety. This necessitates the urgent development of sustainable, green, and safe antibiotic alternatives. Lipopeptides, a class of emerging natural antimicrobial agents, offer considerable promise due to their low toxicity, broad-spectrum antibacterial activity, and environmental compatibility. <i>Bacillus smithii</i>, a facultative anaerobic thermophilic bacterium, exhibits probiotic properties, including antibacterial and anti-inflammatory effects. However, research on its antimicrobial components, particularly their isolation, purification, and mechanistic understanding, remains limited. This study focused on strains of <i>B. smithii</i> XY1 and <i>B. smithii</i> DSM4216<sup>T</sup>. Comparative analysis of their secondary metabolite biosynthetic gene clusters revealed high similarity to the fengycin cluster, suggesting both strains possess the potential for efficient expression of analogous lipopeptide antimicrobials. Lipopeptides were successfully isolated and purified using an ammonium sulfate-ethanol extraction method. <i>In vitro</i> assays demonstrated that these lipopeptides possess broad-spectrum inhibitory activity, effectively suppressing the growth, biofilm formation, and swarming motility of pathogenic bacteria. The minimum inhibitory concentration (MIC) for all pathogenic bacteria tested was less than 62.5&#xa0;μg/mL. Furthermore, the lipopeptides alleviated bacterial infection in a zebrafish model. Mechanistically, the lipopeptides inhibited the quorum sensing (QS) system of <i>Burkholderia cenocepacia</i> H111, specifically targeting the <i>Burkholderia</i> diffusible signal factor (BDSF) associated signaling pathway. This interference resulted in the suppression of the pathogen’s group behaviors and virulence factor expression. This work establishes a theoretical foundation for developing <i>B. smithii</i>-derived lipopeptides as novel natural antimicrobial agents. The strategy of targeting QS inhibition demonstrates significant potential for future antimicrobial interventions.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Broad-Spectrum Antibacterial Action of Lipopeptides Derived from Bacillus smithii by Targeting Quorum Sensing

  • 期刊论文

  • 发表日期：

    2025年10月6日

查看全文
  • Nan Zhao,
  • Xinyue Fan,
  • Muhammad Naveed Sheas,
  • Ting Yu,
  • Fujie Yan

摘要

Foodborne pathogenic microorganisms and the escalating crisis of antibiotic resistance present significant threats to global public health and food safety. This necessitates the urgent development of sustainable, green, and safe antibiotic alternatives. Lipopeptides, a class of emerging natural antimicrobial agents, offer considerable promise due to their low toxicity, broad-spectrum antibacterial activity, and environmental compatibility. Bacillus smithii, a facultative anaerobic thermophilic bacterium, exhibits probiotic properties, including antibacterial and anti-inflammatory effects. However, research on its antimicrobial components, particularly their isolation, purification, and mechanistic understanding, remains limited. This study focused on strains of B. smithii XY1 and B. smithii DSM4216T. Comparative analysis of their secondary metabolite biosynthetic gene clusters revealed high similarity to the fengycin cluster, suggesting both strains possess the potential for efficient expression of analogous lipopeptide antimicrobials. Lipopeptides were successfully isolated and purified using an ammonium sulfate-ethanol extraction method. In vitro assays demonstrated that these lipopeptides possess broad-spectrum inhibitory activity, effectively suppressing the growth, biofilm formation, and swarming motility of pathogenic bacteria. The minimum inhibitory concentration (MIC) for all pathogenic bacteria tested was less than 62.5 μg/mL. Furthermore, the lipopeptides alleviated bacterial infection in a zebrafish model. Mechanistically, the lipopeptides inhibited the quorum sensing (QS) system of Burkholderia cenocepacia H111, specifically targeting the Burkholderia diffusible signal factor (BDSF) associated signaling pathway. This interference resulted in the suppression of the pathogen’s group behaviors and virulence factor expression. This work establishes a theoretical foundation for developing B. smithii-derived lipopeptides as novel natural antimicrobial agents. The strategy of targeting QS inhibition demonstrates significant potential for future antimicrobial interventions.