目的:探讨TrxA在类鼻疽伯克霍尔德菌（Burkholderia pseudomallei，B. pseudomallei）中的生物功能，重点探究TrxA对B. pseudomallei生物活性的影响。 方法:采用同源重组技术构建TrxA基因缺失（ΔTrxA）株，并通过电击转化获得回补（ΔTrxA∷TrxA）株，以野生型（wild type，WT）B. pseudomallei为对照，系统性评估三株菌在生长能力、运动性、生物膜形成、抗药性、氧化应激能力及感染能力几大方面的差异。具体实验包括：生长曲线检测、点板法与面积测量法评估运动性、结晶紫染色法检测生物膜形成、药敏板测定抗药谱、Kirby‑Bauer法评估氧化应激耐受性，以及利用菌落计数与CCK‑8法分析细菌对宿主细胞的黏附和毒性。 结果:与WT和ΔTrxA∷TrxA株相比，ΔTrxA株的生长速度明显减缓、运动能力明显降低（P<0.05）；对宿主细胞感染能力和毒性也明显降低（P<0.05）。在生物膜形成方面，ΔTrxA株在24 h内形成的生物膜较WT增强，但至72 h时三者差异无统计学意义（P>0.05）；ΔTrxA株对部分抗生素的耐受性增强；而三者对过氧化氢的氧化应激能力差异无统计学意义（P>0.05）；上述结果表明TrxA在B. pseudomallei生物活性及对宿主的感染与毒性发挥方面具有重要作用。 结论:TrxA在调控B. pseudomallei的生长、运动性、生物膜形成、感染能力及毒性发挥等方面发挥了关键作用，本研究为进一步阐明B. pseudomallei的致病机制及开发新的治疗靶点提供了理论基础。

Objective:To investigate the biological function of TrxA in Burkholderia pseudomallei （B. pseudomallei）， with a focus on exploring the role of TrxA in regulating B. pseudomallei's biological activities. Methods:A TrxA gene deletion mutant （ΔTrxA） was constructed using homologous recombination， and a complemented strain （ΔTrxA∷TrxA） was obtained via electroporation. Using the wild‑type （WT） B. pseudomallei strain as a control， systematically evaluated differences among the three strains in terms of growth， motility， biofilm formation， antibiotic resistance， oxidative stress tolerance， and infectivity. Specific assays included： growth curve analysis， point plate and area measurement methods were used to evaluate motility， crystal violet staining was used to detect biofilm formation， drug sensitivity plate was used to test antibiotic susceptibility， the Kirby‑Bauer method was used to evaluate oxidative stress tolerance， and colony counting and CCK‑8 assays were used to assess bacterial adhesion and cytotoxicity to the host cells. Results:Compared to the WT and ΔTrxA∷TrxA strains， the ΔTrxA mutant exhibited significantly reduced growth and motility （P<0.05）， as well as significantly decreased infectivity and cytotoxicity toward the host cells （P<0.05）. Regarding biofilm formation， the ΔTrxA strain formed a more robust biofilm than the WT strain at 24 hour. However， by the 72 hour， no statistical significant differences were observed among the three strains （P>0.05）. The ΔTrxA strain showed increased resistance to certain antibiotics， while there were no statistical significant differences in tolerance to oxidative stress induced by hydrogen peroxide among all three strains （P>0.05）. These findings suggested that TrxA plays a critical role in B. pseudomallei's biological activity， as well as infectivity and cytotoxic against the host cells. Conclusion:TrxA plays a key role in regulating the growth， motility， biofilm formation， infectivity， and cytotoxicity of B. pseudomallei. This study provides a theoretical basis for further elucidating the pathogenic mechanisms of B. pseudomallei and developing novel therapeutic targets.

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国家自然科学基金（82060001）；海南医科大学大学生创新创业项目（S202411810006）