中国畜牧兽医 ›› 2023, Vol. 50 ›› Issue (4): 1340-1351.doi: 10.16431/j.cnki.1671-7236.2023.04.006

• 生物技术 • 上一篇    下一篇

LIPI-4 EⅡC调控单增李斯特菌关键毒力因子转录的研究

刘彩霞, 史唯地, 寇丽君, 马勋, 王静, 高盛杰, 吕双飞, 陈旭珂, 曾东东, 孔翠莲, 任慧杰   

  1. 石河子大学动物科技学院, 石河子 832000
  • 发布日期:2023-04-06
  • 通讯作者: 马勋, 王静 E-mail:maxun779@126.com;wjtry100@163.com
  • 作者简介:刘彩霞,E-mail:2806870964@qq.com。
  • 基金资助:
    国家自然科学基金(32160834、32160833、31860712);省部共建绵羊遗传改良与健康养殖国家重点实验室开放课题(MYSKLKF201905);动物疾病防控兵团重点实验室开放课题(2020BTDJ05)

Regulation of Transcription of Key Virulence Factors of Listeria monocytogenes by LIPI-4 EⅡC

LIU Caixia, SHI Weidi, KOU Lijun, MA Xun, WANG Jing, GAO Shengjie, LYU Shuangfei, CHEN Xuke, ZENG Dongdong, KONG Cuilian, REN Huijie   

  1. College of Animal Science and Technology, Shihezi University, Shihezi 832000, China
  • Published:2023-04-06

摘要: 【目的】探究单增李斯特菌(LM)毒力岛4(LIPI-4)中膜透性酶ⅡC (EⅡC)对LM关键毒力基因表达的影响。【方法】构建分离株LM928 EC基因缺失株LM928ΔEC和回补菌株CLM928ΔEC,测定各菌株的生长曲线和对不同糖的发酵情况,测定侵染人脑微血管内皮细胞(HCMEC/D3)后的黏附、侵袭和胞内增殖能力,利用实时荧光定量PCR方法检测在脑心浸液(BHI)培养条件下和侵染HCMEC/D3后各菌株毒力基因的转录水平。【结果】成功构建LM928 EC基因缺失株LM928ΔEC和回补菌株CLM928ΔEC。EC基因的缺失不影响LM928的生长和对葡萄糖、纤维二糖、果糖、鼠李糖、七叶苷和水杨苷的发酵。EC基因缺失后,LM928对HCMEC/D3的侵袭率极显著下降(P<0.01),黏附能力无显著变化(P>0.05)。LM928ΔEC胞内增殖菌量在2~4 h时显著低于LM928和CLM928ΔEC(P<0.05),但在8~12 h时均显著高于LM928和CLM928ΔEC(P<0.05)。在BHI培养条件下,LM928ΔEC毒力基因hly、prfA、actAplcB、inlA、inlBinlCmpl转录水平极显著下调(P<0.01),毒力基因plcA转录水平极显著上调(P<0.01);在侵染HCMEC/D3后,LM928ΔEC毒力基因hly、prfAinlBinlCmpl转录水平相对于LM928和CLM928ΔEC显著或极显著上调(P<0.05;P<0.01),毒力基因plcAinlA相比于CLM928ΔEC极显著下调(P<0.01),毒力基因actAplcB转录水平无显著差异(P>0.05)。【结论】LIPI-4中EⅡC不参与LM928的生长及其对部分糖的发酵,能调控LM中重要的侵袭相关基因和毒力相关基因。本试验结果为进一步探究EⅡC在LM和LIPI-4中的作用奠定基础。

关键词: 单增李斯特菌; 毒力岛4; 膜透性酶ⅡC; 毒力基因

Abstract: 【Objective】 This study was aimed to investigate the effect of membrane permease ⅡC(EⅡC) gene in Listeria monocytogenes (LM) pathogenicity island 4 (LIPI-4) on the key virulence factor genes expression.【Method】 The EC gene deletion strain LM928ΔEC and complementary strain CLM928ΔEC of isolate LM928 were constructed.The growth curve of each strain and the fermentation of different sugars were determined.The adhesion,invasion and intracellular proliferation of each strain to human brain microvascular endothelial cells (HCMEC/D3) were determined.The transcript levels of virulence genes of each strain were detected using Real-time quantitative PCR under BHI medium and HCMEC/D3.【Result】 LM928 EC gene deletion strain LM928ΔEC and complementary strain CLM928ΔEC were successfully constructed.Compared with the LM928,the LM928ΔEC strain showed consistent growth curves and fermentability to glucose,cellobiose,fructose,rhamnose,esculin and salicin.The invasive ability of LM928ΔEC decreased extremely significantly (P<0.01), but the adhesion ability was not change significantly (P>0.05).The amount of intracellular proliferation of LM928ΔEC was significantly lower than that of LM928 and CLM928ΔEC from 2 to 4 h post-infection (P<0.05),but it was significantly higher than that of LM928 and CLM928ΔEC from 8 to 12 h post-infection (P<0.05).Compared with LM928 and CLM928ΔEC,in BHI medium,the transcriptional levels of hly,prfA,actA,plcB, inlA,inlB,inlC and mpl genes of LM928ΔEC were extremely significantly down-regulated (P<0.01),the transcriptional level of plcA gene was extremely significantly up-regulated (P<0.01).While in HCMEC/D3 cell,the transcriptional levels of hly,prfA,inlB,inlC and mpl genes of LM928ΔEC were significant or extremely significantly up-regulated (P<0.05 or P<0.01),the transcriptional levels of plcA and inlA genes were extremely significant down-regulated (P<0.01),and there was no significant difference between the transcriptional levels of actA and plcB genes.【Conclusion】 EⅡC in LIPI-4 did not affect the growth and partial sugar fermentation of LM928,could regulate important invasion-related genes and virulence-related genes in LM,which laid a foundation for further exploration of the role of EⅡC in LM and LIPI-4.

Key words: Listeria monocytogenes; pathogenicity island 4; membrane permease ⅡC; virulence gene

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