吉林大学学报(医学版) ›› 2025, Vol. 51 ›› Issue (4): 921-928.doi: 10.13481/j.1671-587X.20250408

• 基础研究 • 上一篇    下一篇

多重耐药铜绿假单胞菌群体感应相关基因表达及其对生物膜形成和耐药性的影响

刘岩1,潘蓓珍1,杨继飞1,张先宇1,丁文博1,宋伶俐2,赵云冬1()   

  1. 1.北华大学医学技术学院临床生化及分子生物学检验教研室,吉林 吉林 132013
    2.北华大学附属 医院检验科微生物室,吉林 吉林 132001
  • 收稿日期:2024-09-20 接受日期:2024-11-19 出版日期:2025-07-28 发布日期:2025-08-25
  • 通讯作者: 赵云冬 E-mail:18604498530@163.com
  • 作者简介:刘 岩(1999-),女,吉林省长春市人,在读硕士研究生,主要从事细菌耐药性方面的研究。
  • 基金资助:
    吉林省科技厅科技发展计划项目(20230202059NC);吉林省科技厅科技发展计划项目(20230204085YY);北华大学研究生创新计划项目(研创合字〔2023〕022)

Expression of quorum sensing related genes in multidrug-resistant Pseudomonas aeruginosa and its effects on biofilm formation and drug resistance

Yan LIU1,Beizhen PAN1,Jifei YANG1,Xianyu ZHANG1,Wenbo DING1,Lingli SONG2,Yundong ZHAO1()   

  1. 1.Department of Clinical Biochemistry and Molecular Biology,School of Medical Technology,Beihua University,Jilin 132013,China
    2.Microbiology Room,Laboratory of Laboratory,Affiliated Hospital,North China University,Jilin 132001,China
  • Received:2024-09-20 Accepted:2024-11-19 Online:2025-07-28 Published:2025-08-25
  • Contact: Yundong ZHAO E-mail:18604498530@163.com

摘要:

目的 探讨临床多重耐药铜绿假单胞菌群体感应相关基因表达对生物膜形成和耐药性的影响,阐明耐药性增加的机制。 方法 收集77株铜绿假单胞菌,根据其耐药性将菌株分为多重耐药组和敏感组,微孔板法构建生物膜筛选最佳形成条件,采用光学显微镜观察2组铜绿假单胞菌生物膜形成情况,结晶紫染色半定量法检测2组铜绿假单胞菌生物膜形成能力,微量肉汤稀释法检测2组铜绿假单胞菌对群体感应抑制剂呋喃酮(C-30)的最低抑菌浓度(MIC)值,试剂盒法提取2组铜绿假单胞菌的RNA,改良TRIzol法提取2组铜绿假单胞菌中多重耐药组浮游态和生物膜态RNA,实时荧光定量PCR(RT-qPCR)法检测2组以及加入C-30抑制剂前后铜绿假单胞菌中lasR/IRhlR/IPqsR/A mRNA表达水平。 结果 77株铜绿假单胞菌标本中有56株多重耐药株(多重耐药组),21株全敏感株(敏感组)。构建生物膜最佳条件,当铜绿假单胞菌浓度为1.5×108 CFU·mL-1、培养时间为48 h时生物膜形成量最多;77株铜绿假单胞菌标本的生物膜阳性率为91%,其中生物膜强阳性、中等阳性、弱阳性和阴性分别占16%、34%、41%及9%,多重耐药株的生物膜阳性率为96%,且多重耐药组的生物膜形成能力高于敏感组(P<0.05)。当群体感应抑制剂C-30的浓度为8 mg·L-1时,可抑制多数铜绿假单胞菌生物膜的形成,且浓度越高,抑制作用越明显;浮游态RNA和生物膜态RNA的吸光度(A)值在1.8~2.0。RT-qPCR法,与浮游态比较,生物膜态的铜绿假单胞菌重群体感应相关基因lasR/IRhlR/IPqsR/A mRNA表达水平升高(P<0.01);与未加抑制剂组比较,加入抑制剂组铜绿假单胞菌中生物膜态的群体感应相关基因lasR/IRhlR/IPqsR/A mRNA表达水平降低(P<0.01)。 结论 多重耐药铜绿假单胞菌的群体感应相关基因高表达会促进生物膜的形成,从而导致耐药性增加。

关键词: 铜绿假单胞菌, 生物膜, 群体感应系统, 实时荧光定量PCR, 耐药性

Abstract:

Objective To discuss the effect of quorum sensing-related gene expression on biofilm formation and drug resistance in clinically multidrug-resistant Pseudomonas aeruginosa, and to clarify the mechanism of enhacing drug resistance. Methods A total of 77 strains of Pseudomonas aeruginosa were collected. Based on drug resistance, the strains were divided into multidrug-resistant group and sensitive group. The optimal biofilm formation conditions were determined using the microtiter plate method; biofilm formations of the stains in both groups was observed under an optical microscope; crystal violet staining was used to semiquantitatively detect biofilm formation ability of P. aeruginosa in both groups; microbroth dilution method was used to determine the minimal inhibitory concentration (MIC) values of the quorum sensing inhibitor (C-30) against Pseudomonas aeruginosa in both groups; RNA was extracted from two groups using a commercial kit, while RNA from planktonic state and biofilm state of multidrug-resistant strains was extracted using modified TRIzol method; real-time fluorescence quantitative PCR (RT-qPCR) method was used to detect the mRNA expression levels of quorum sensing-related genes (lasR/IRhlR/IPqsR/A) of the stains in multidrug-resistant group and sensitive group, as well as before and after adding the quorum sensing inhibitor C-30. Results Among 77 strains of Pseudomonas aeruginosa, 56 were multidrug-resistant (multidrug-resistant group) and 21 were fully sensitive(sensitive group). Optimal biofilm formation occurred at a bacterial concentration of 1.5×108 CFU·mL-1 with 48 h incubation. The biofilm positivity rate was 91%, with strongly positive, moderately positive, weakly positive, and negative biofilms accounting for 16%, 34%, 41%, and 9%, respectively. The biofilm positivity rate in multidrug-resistant strains was 96%, and biofilm formation ability in multidrug-resistant group was higher than that in sensitive group (P<0.05). When the concentration of C-30 was 8 mg·L-1 the biofilm formation in most Pseudomonas aeruginosa was inhibited, with enhanced suppression at higher concentrations. The absorbtion (A) value of both planktonic-state and biofilm-state RNA ranged from 1.8 to 2.0. The RT-qPCR results showed that compared with planktonic state, the expression levels of lasR/IRhlR/I, and PqsR/A mRNA of the stains in biofilm state were significantly increased (P<0.01). Compared with non-inhibitor group, the expression levels of lasR/IRhlR/I, and PqsR/A mRNA in biofilm state of inhibitor-treated group were significantly decreased (P<0.01). Conclusion High expression of quorum sensing-related genes in multidrug-resistant P. aeruginosa promotes biofilm formation, thereby enhancing drug resistance.

Key words: Pseudmonas aeruginosa, Biofilms, Quorum sensing system, Real-time fluorescence quantitative PCR, Drug resistance

中图分类号: 

  • R378.99