Scholarlink

<p><i>Aeromonas dhakensis</i>, an increasingly prevalent pathogen in tropical areas, presents significant risks to public health and the aquaculture industry. This research evaluates the virulence effects of <i>ugd</i> and <i>pho</i>B gene deletions. The double gene deletion mutant strain Δ<i>ugd</i>Δ<i>phoB</i> was obtained by further knocking out the <i>ugd</i> gene in the previously constructed single mutant strain Δ<i>phoB</i>. Phenotypic analyses under phosphate-deficient conditions showed marked decreases in both growth and motility for the Δ<i>ugd</i> and Δ<i>ugd</i>Δ<i>pho</i>B mutants compared to the wild type. Conversely, under phosphate-rich conditions, growth remained stable, although motility variations were noted. The mutants Δ<i>ugd</i>Δ<i>phoB</i> and Δ<i>ugd</i> exhibited diminished resistance to H<sub>2</sub>O<sub>2</sub>, ECPase activity, and antimicrobial peptide resistance, alongside reduced adherence to EPC cells. However, the Δ<i>ugd</i> mutant displayed enhanced biofilm formation. The immunoprotection experiment showed that the protection rate (relative percent survival, RPS) of the Δ<i>ugd</i> mutant strain was 63.3%, which was significantly higher than the 40.0% of the Δ<i>ugd</i>Δ<i>phoB</i> mutant strain. Consistently, the Δ<i>ugd</i> mutant strain also exhibited a more significant degree of virulence attenuation (median lethal dose, LD₅₀ = 2.87 × 10⁸ CFU/mL); in contrast, the LD₅₀ of the Δ<i>ugd</i>Δ<i>phoB</i> mutant strain was 1.23 × 10⁸ CFU/mL. This indicates that the Δ<i>ugd</i> mutant strain has greater potential as an attenuated live vaccine candidate due to its stronger immunoprotective efficacy and lower residual virulence.</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

Dual deletion of ugd and phoB Attenuates virulence and enhances vaccine potential in Aeromonas dhakensis

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2026年1月5日

查看全文
  • Xuesong Li,
  • Mengqi Wang,
  • Liqing Chen,
  • Haibo Gao,
  • Yanrong Lin,
  • Yukun Wu,
  • Shuai Ye,
  • Aodi Yi,
  • Guiying Guo,
  • Lixia Fan,
  • Nuo Yang,
  • Jifeng Zeng,
  • Jiping Zheng

摘要

Aeromonas dhakensis, an increasingly prevalent pathogen in tropical areas, presents significant risks to public health and the aquaculture industry. This research evaluates the virulence effects of ugd and phoB gene deletions. The double gene deletion mutant strain ΔugdΔphoB was obtained by further knocking out the ugd gene in the previously constructed single mutant strain ΔphoB. Phenotypic analyses under phosphate-deficient conditions showed marked decreases in both growth and motility for the Δugd and ΔugdΔphoB mutants compared to the wild type. Conversely, under phosphate-rich conditions, growth remained stable, although motility variations were noted. The mutants ΔugdΔphoB and Δugd exhibited diminished resistance to H2O2, ECPase activity, and antimicrobial peptide resistance, alongside reduced adherence to EPC cells. However, the Δugd mutant displayed enhanced biofilm formation. The immunoprotection experiment showed that the protection rate (relative percent survival, RPS) of the Δugd mutant strain was 63.3%, which was significantly higher than the 40.0% of the ΔugdΔphoB mutant strain. Consistently, the Δugd mutant strain also exhibited a more significant degree of virulence attenuation (median lethal dose, LD₅₀ = 2.87 × 10⁸ CFU/mL); in contrast, the LD₅₀ of the ΔugdΔphoB mutant strain was 1.23 × 10⁸ CFU/mL. This indicates that the Δugd mutant strain has greater potential as an attenuated live vaccine candidate due to its stronger immunoprotective efficacy and lower residual virulence.