模拟微重力对肺炎克雷伯菌生物学特性的影响  

Effect of simulated microgravity on biological characteristics of Klebsiella pneumoniae

作　　者：王甲[1] 王萍[1] 朱敏立[2] 徐冰心[2] 张军[2] 贾莉萍[2] 陈杨[2] 

机构地区：[1]安徽医科大学解放军306医院临床学院,北京100101 [2]解放军306医院,北京100101

出　　处：《军事医学》2015年第2期92-96,共5页Military Medical Sciences

基　　金：全军医学科研"十二五"重点项目(BWS11J051)

摘　　要：目的研究模拟微重力对肺炎克雷伯菌(KPN)生长、形态、蛋白表达以及4种毒力基因表达的影响。方法实验分为微重力组和对照组,采用回转器模拟微重力模型处理微重力组菌株,检测KPN微重力下的生长情况,电镜观察细菌形态,表面增强激光解吸电离飞行时间质谱技术(SELDI-TOF-MS)检测蛋白质表达及采用实时(real-time,RT)PCR检测ureA、wabG、uge、fimH 4种毒力基因的表达。结果微重力组与对照组相比,KPN的生长加快,最终菌量增加;扫描电镜见部分菌体形态发生变化,细长的菌体增多,透射电镜见细胞质内颗粒状物质增多;质谱分析结果有18个蛋白峰表达发生变化,表达上调和下调各9个,经蛋白库共检索出21个与其相对分子质量(Mr)相近蛋白,其中13个功能已知的蛋白与细菌的生命活动密切相关;RT-PCR结果表明,4种毒力基因表达均下调。结论微重力使KPN生长加快、繁殖能力增强,菌体形态、蛋白表达以及4种毒力基因表达均发生变化,微重力使KPN的生物学特性发生改变。Objective To investigate the effect of simulated microgravity on growth,morphology,protein expression and virulence gene expression of Klebsiella pneumoniae（ KPN）. Methods KPN was divided into simulated microgravity group and control group in the experiment. The former group was in the ambient of simulated microgravity in a clinostat. The bacterial growth curves,morphologyical changes in electron microscopy,and protein expression were detected by SELDITOF-MS,and the expression of 4 virulence genes（ ureA,wabG,uge and fimH） by real-time fluorescence quantitative PCR（ RT-PCR） in both groups. Results Compared with the control group,the growth of KPN under simulated microgravity was accelerated,and the total bacterial count increased in microgravity group. The bacterial morphology in microgravity group was changed under scanning electron microscopy（ SEM）,and thinner and longer bacteria were increased. The transmission electron microscopy（ TEM） analysis revealed increase in cytoplasmic granular substance in microgravity group. Proteome analysis showed that the expression of 18 proteins was changed,half of which up-regulated and the rest were down-regulated. Those 18 proteins were searched in the protein library. And 21 proteins of a similar molecular mass were retrieved,13 of which,proteins with known functions,were closely related to bacterial life activities. RT-PCR results showed that four virulence genes of KPN were down-regulated. Conclusion Upon exposure to simulated microgravity,the growth and reproduction of KPN are accelerated and enhanced. The bacterial morphology is changed. The strain＇ s protein expression and four virulence genes expressionare also changed. Therefore,microgravity can change the characteristics of KPN.

关 键 词：失重模拟 肺炎克雷伯菌 蛋白 基因 

分 类 号：R852.22[医药卫生—航空、航天与航海医学]