Soydam Semra, Has Elif Gamze, Sürkaç Tuba Nur, Akçelik Mustafa, Akçelik Nefise
Vaccine Institute, Department of Vaccine Technology, Hacettepe University, TR-06100, Ankara, Turkey.
Faculty of Science, Department of Biology, Ankara University, TR-06100, Ankara, Turkey.
Arch Microbiol. 2025 Feb 17;207(3):63. doi: 10.1007/s00203-025-04248-9.
In this study, rfaG, luxS, and bcsE gene mutants of S. Typhimurium ATCC 14028 wild-type strain were generated, and their effects on bacterial physiology and pathogenicity were investigated. Biofilm production capacity and mobility of mutant strains were found to be significantly reduced. Immune response stimulation of 6-8 week-old BALB/c mice infected with wild-type and mutants was evaluated on days 0 and 21 for IL-6, IFN-γ, and IgG, and then systemic infection in mice was determined by the amount of Salmonella recovered from the cecum, spleen, and liver organs. The specific IgG antibody level and the expression level of the cytokines IFN-γ and IL-6 were found to be significantly reduced in mice inoculated with mutant strains compared to the control group. The highest level of colonization in the organs was found in the cecum, and the lowest level of colonization was detected in the liver. In the wild-type-infected group, splenomegaly and staining of the liver were detected. In the groups of mice infected with bcsE and luxS mutants, these symptoms were at a low level. In the groups infected with the rfaG mutant, no significant lesions were detected in the organs.
在本研究中，构建了鼠伤寒沙门氏菌ATCC 14028野生型菌株的rfaG、luxS和bcsE基因突变体，并研究了它们对细菌生理学和致病性的影响。发现突变菌株的生物膜形成能力和运动性显著降低。在第0天和第21天评估感染野生型和突变体的6-8周龄BALB/c小鼠的免疫反应刺激情况，检测白细胞介素-6（IL-6）、干扰素-γ（IFN-γ）和免疫球蛋白G（IgG），然后通过从盲肠、脾脏和肝脏器官中回收的沙门氏菌数量来确定小鼠的全身感染情况。与对照组相比，接种突变菌株的小鼠中特异性IgG抗体水平以及细胞因子IFN-γ和IL-6的表达水平显著降低。在器官中定殖水平最高的是盲肠，最低的是肝脏。在野生型感染组中，检测到脾脏肿大和肝脏染色。在感染bcsE和luxS突变体的小鼠组中，这些症状程度较低。在感染rfaG突变体的组中，未在器官中检测到明显病变。
