生物技术进展 ›› 2026, Vol. 16 ›› Issue (2): 388-394.DOI: 10.19586/j.2095-2341.2025.0090

• 研究论文 • 上一篇    

pSLT质粒的转移及其对肠道细胞凋亡的影响

洪甜1(), 赵璐璐1, 杜一凡2, 李静雯1, 陈尔凝1, 杜美红1()   

  1. 1.北京市科学技术研究院分析测试研究所(北京市理化分析测试中心),北京  100094
    2.北京城市学院生物医药学部,北京  100094
  • 收稿日期:2025-07-29 接受日期:2025-12-25 出版日期:2026-03-25 发布日期:2026-04-27
  • 通讯作者: 杜美红
  • 作者简介:洪甜 E-mail: htian1025@163.com
  • 基金资助:
    北京市科学技术研究院创新工程项目(25CA011)

Transfer of the pSLT Plasmid and its Impact on Intestinal Cell Apoptosis

Tian HONG1(), Lulu ZHAO1, Yifan DU2, Jingwen LI1, Erning CHEN1, Meihong DU1()   

  1. 1.Institute of Analysis and Testing,Beijing Academy of Science and Technology (Beijing Center for Physical & Chemical Analysis),Bejing 100094,China
    2.School of Biomedicine,Beijing City University,Beijing 100094,China
  • Received:2025-07-29 Accepted:2025-12-25 Online:2026-03-25 Published:2026-04-27
  • Contact: Meihong DU

摘要:

pSLT质粒是主要存在于鼠伤寒沙门氏菌株中的一种特异性毒力质粒,探讨了沙门氏菌pSLT毒力质粒水平基因转移(horizontal gene transfer,HGT)的可行性,及其对细胞坏死和凋亡的影响。采用λRed同源重组技术,将pKD46质粒来源的Kana抗性基因整合插入沙门氏菌的pSLT质粒中;以沙门氏菌(ATCC 14028)为供体菌,大肠杆菌(ATCC 25922)为受体菌,通过M9培养基平板接合法进行接合转移,获得的接合菌在含有卡那霉素的麦康凯液体培养基中进行产酸产气培养验证,划线培养取单菌落进行菌液PCR鉴定和测序鉴定比对;以人结肠癌细胞HCT116为肠道代表菌,将接合菌以感染复数(multiplicity of infection,MOI)100进行作用,通过流式细胞术检测细胞坏死和凋亡情况。结果发现,含有卡那霉素的营养琼脂平板上有单菌落生长,Kana抗性基因片段成功重组插入pSLT;接合菌在含有卡那霉素的麦康凯液体培养基中有产酸产气现象,pSLTKana质粒接合转移至大肠杆菌;与对照组相比,ATCC 25922处理组未造成Annexin V/PI双阳性细胞比例的显著变化(P>0.05),ATCC 25922 pSLT和ATCC 14028处理组均表现出显著降于Annexin V/PI双阳性细胞比例(P<0.01)。通过构建ATCC 14028 pSLTKana重组菌株,证实了沙门氏菌携带的pSLT毒力质粒向大肠杆菌进行水平基因转移的可行性,ATCC 25922 pSLTKana对肠道细胞的坏死和凋亡存在潜在的抑制作用,为临床治疗和公共卫生安全监管提供了重要的科学数据和思路。

关键词: 沙门氏菌, pSLT, 大肠杆菌, 接合转移

Abstract:

The pSLT plasmid is a specific virulence plasmid primarily found in Salmonella enterica serovar Typhimurium strains. This study aimed to explore the feasibility of horizontal gene transfer (HGT) of the Salmonella pSLT virulence plasmid and investigate its effects on cell necrosis and apoptosis. The Kanamycin resistance gene derived from plasmid pKD46 was integrated into the Salmonella pSLT plasmid using λRed homologous recombination technology. Salmonella enterica serovar Typhimurium (ATCC 14028) served as the donor strain, and Escherichia coli (ATCC 25922) as the recipient strain. Conjugation was performed using the M9 minimal medium plate mating method. The obtained transconjugants were cultured in Kanamycin-supplemented MacConkey broth to verify acid and gas production. Single colonies were isolated, followed by confirmatory PCR and sequencing for the inserted Kana gene. Human colon carcinoma cells (HCT116), representing intestinal cells, were infected with transconjugants at a multiplicity of infection (MOI) of 100. Cell necrosis and apoptosis were assessed using flow cytometry (Annexin V/PI staining). The results showed that single colonies grew on nutrient agar plates containing Kanamycin, confirming successful recombination and insertion of the Kana gene fragment into pSLT (creating pSLTKana). Transconjugants exhibited acid and gas production in Kanamycin-supplemented MacConkey broth, demonstrating the successful conjugative transfer of the pSLTKana plasmid to Escherichia coli. Compared to the control group, the ATCC 25922 (wild-type E. coli) treatment group did not cause a significant change (P>0.05) in the proportion of Annexin V/PI double-positive cells (indicating late apoptosis/necrosis). In contrast, both the ATCC 25922 pSLTKanaE. coli harboring pSLT) and ATCC 14028 (Salmonella with native pSLT) treatment groups showed a significant reduction (P<0.01) in the proportion of Annexin V/PI double-positive cells. By constructing the ATCC 14028 pSLTKana recombinant strain, this study confirmed the feasibility of HGT of the pSLT virulence plasmid from Salmonella to E. coli. The ATCC 25922 pSLTKana strain exhibited a potential inhibitory effect on necrosis and apoptosis in intestinal cells. These findings provide crucial scientific data and insights for clinical treatment strategies and public health safety oversight.

Key words: Salmonella, pSLT, Escherichia coli, conjugation transfer

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