The effects of the bcsE gene and BcsE protein on bacterial physiology and pathogenicity in SalmonellaTyphimurium and Salmonella Group C1 were investigated. It was observed that biofilm and pellicle formation did not occur in the bcsE gene mutants of wild-type strains. Besides, the ‘rdar’ (red, dry, rough) biofilm morphotype in wild-type strains changed significantly in the mutants. In terms of the bcsE gene, the swimming and swarming motility in mutant strains showed a dramatic increase compared to the wild-type strains. The Salmonella bcsE gene was cloned into Escherichia coli BL21, and the his-tagged protein produced in this strain was purified to obtain polyclonal antibodies in BALB/c mice. The antibodies were showed labeled antigen specificity to the BscE protein. As a result of immunization and systemic persistence tests carried out with BALB/c mice, BscE protein was determined to trigger high levels of humoral and cellular responses (Th1 cytokine production, IgG2a/IgG1 > 1). Systemic persistence in the liver and spleen samples decreased by 99.99% and 100% in the bcsE mutant strains. Finally, invasion abilities on HT-29 epithelial cells of wild-type strains were utterly disappeared in their bcsE gene mutant strains.

中文翻译：

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bcsE基因在沙门氏菌致病中的作用

研究了bcsE基因和BcsE蛋白对鼠伤寒沙门氏菌和沙门氏菌C1组细菌生理学和致病性的影响。观察到在野生型菌株的 bcsE 基因突变体中没有发生生物膜和表膜的形成。此外，野生型菌株中的“rdar”（红色、干燥、粗糙）生物膜形态型在突变体中发生了显着变化。在bcsE基因方面，突变株的游动和集群运动与野生株相比显着增加。将沙门氏菌bcsE基因克隆到大肠杆菌BL21中，对该菌株产生的his标签蛋白进行纯化，得到BALB/c小鼠的多克隆抗体。抗体显示出对 BscE 蛋白的标记抗原特异性。作为对 BALB/c 小鼠进行的免疫和全身持久性测试的结果，确定 BscE 蛋白引发高水平的体液和细胞反应（Th1 细胞因子产生，IgG2a/IgG1 > 1）。在 bcsE 突变株中，肝脏和脾脏样本中的系统持久性分别下降了 99.99% 和 100%。最后，野生型菌株对HT-29上皮细胞的侵袭能力在其bcsE基因突变菌株中完全消失。