应用RNAⅢ抑制肽(RIP)抑制葡萄球菌毒素产生的实验研究

The Experimental Study of RIP Inhibiting Staphylococcus Aureus Producing Toxins in Vitro

通过体外实验研究RNAⅢ抑制肽(RIP)抑制葡萄球菌产生肠毒素和溶血素的效果。将200μL浓度为2.5%的二甲基亚砜(DMSO,对照组)和1mg/mL的R IP分别加入到200μL浓度1×108/mL的TECRA菌液,培养3h后,定量检测两组菌液中SEB的含量。将分别含有0.75% DMSO、100μg左氧氟沙星、40μg RIP和40μg RIP+100μg左氧氟沙星的菌液与50μL含有4%家兔红细胞的PBS液共同培养1h后,用酶标仪检测各组上清液中血红蛋白的含量。在ELLISA反应的5、10、30min三个时间点,RIP组菌液中SEB含量均明显低于DMSO组,两组数据具有极显著性差异(p<0.001);RIP组和左氧组菌液中的溶血素的含量明显低于空白组(p<0.05,p<0.01),联合用药组菌液中的溶血素含量明显低于空白组和RIP组,与左氧组相比差别不显著。说明RIP可以有效抑制金葡菌肠毒素和溶血素的产生,与抗生素联用有一定的协同功效。

To investigate the inhibiting roll of RNAⅢ inhibiting peptide（RIP） on staphylococcus aureus producing toxins（SEB and hemolysin）,adding 200 μL DMSO（2.5%,control group）and RIP（1 mg/mL,RIP group） to 200 μL TECRA_medium（1×108/cells·mL）.three hours later,SEB in the medium of two group was quantitively detected;Incubating 50 μL PBS（containing 4% rabbit erythrocytes）with 0.75% DMSO,40 μg RIP,100ug levofloxacin and 40 μg RIP＋100 μg levofloxacin for 1hr respectively.Then,the amount of hemoglobin released to the supernatants was detected.On the three time point（5,10,30 min） of the ELLISA reaction,all the density of,SEB of RIP group was lower than control group（p0.001）.The level of hemolysin of RIP group and Levofloxacin group was obviously lower than control group（p0.05,p0.01）,otherwise,RIP＋Levofloxacin group was more lower than control group and RIP group（p0.05）,there was no significant difference between Levofloxacin group（p0.05）.It is conclused that RIP can effectively inhibit staphylococcus aureus producing SEB and hemolysin,it has cooperation antibiotics.