Abstract：In order to explore the effect of Salmonella typhi type 6 secretion system (T6SS) on SopE expression and clarify the molecular mechanism, the wild Salmonella typhi strain (WT-pBAD33), T6SS functional molecule-deficient strain (ΔsciG-pBAD33) and complementing strain (C-ΔsciG) carrying sopE∷3×Flag were constructed by suicide plasmid homologous recombination method. The strains were constructed to infect macrophage THP-1 and cultured in simulated macrophage environment (LPM medium, microaerobic). The effect of T6SS on the expression of SopE was investigated by real-time fluorescence quantitative polymerase chain reaction (qRT-PCR) and Western blot experiments. The β-galactosidase activity test further verified the transcription level of sopE gene promoter, and the T6SS functional protein SciG was purified by Ni column. The regulation effect of SciG protein on the sopE gene promoter was analyzed by electrophoretic mobility shift assay (EMSA). The results demonstrated that the expression level of SopE in ΔsciG-pBAD33 was significantly lower than that in WT-pBAD33; SciG protein could not directly bind to the sopE gene promoter region. It was concluded that Salmonella typhi T6SS affects the expression of SopE, but its functional protein SciG can not directly regulate the expression of sopE gene.
石书娟，刘秀雯，翁轶玮，党娟娟，李泽宇，张盈，黄新祥. 伤寒沙门菌Ⅵ型分泌系统对SopE表达影响的初步研究[J]. 微生物与感染, 2023, 18(1): 21-28.
SHI Shujuan, LIU Xiuwen, WENG Yiwei, DANG Juanjuan, LI Zeyu, ZHANG Ying, HUANG Xinxiang. Preliminary study on the effect of Salmonella typhi type Ⅵ secretion system on the expression of SopE. JOURNAL OF MICROBES AND INFECTIONS, 2023, 18(1): 21-28.
2023, Vol. 18 
