摘要
目的研究表皮葡萄球菌icaA和icaR基因与生物被膜形成的相关性。方法收集湘雅三医院机械通气患者分离表皮葡萄球菌26株,按生物被膜成膜能力分成生物被膜阳性菌组和生物被膜阴性菌组各13株。采用RT-PCR分别对2组细菌icaA和icaR基因灰度比进行检测;采用real-time PCR分别检测2组细菌icaA和icaR基因的表达,并通过2-△△Ct方法进行相对定量。结果 RT-PCR结果显示icaA基因在生物被膜阳性组中的灰度比为0.96~1.38,在生物被膜阴性组中为0.89~1.56,表达差异无统计学意义(T=10.65,P=0.057);同理,icaR基因在生物被膜阳性组中的灰度比为0.79~1.24,在生物被膜阴性组中则为0.80~1.36,表达差异亦无统计学意义(T=14.62,P=0.479)。但icaA基因在生物被膜阳性组中的平均秩(16.35)明显高于生物被膜阴性菌组(10.65),而icaR基因生物被膜阳性组的平均秩(12.38)明显小于生物被膜阴性菌组(14.62)。real-time PCR检测发现表皮葡萄球菌生物被膜阳性组icaA基因的表达量(△CT=4.86)是生物被膜阴性组(△CT=13.57)的418.8倍(t=61.890,P<0.01),而icaR基因的表达量(△CT=19.03)仅为生物被膜阴性组(△CT=11.85)的1/145(t=21.330,P<0.01)。结论 icaA基因与表皮葡萄球菌生物被膜的形成呈正相关,而icaR基因与表皮葡萄球菌生物被膜的形成呈负相关。
Objective To study the correlations between icaA and icaR genes with biofilm formation of Staphylococcusepidermidis （S. epidermidis） . Methods 26 strains of S. epidermidis isolated from tracheal catheter of patients with mechanicalventilation in ICU of the Third Xiangya Hospital were collected and divided into biofilm positive group （13 strains） andbiofilm negative group （13 strains） according to biofilm formation ability. The gray scale ratios of icaA and icaR genes intwo groups were determined by reverse transcription PCR. The expressions of icaA and icaR genes in two groups were detected byreal time PCR, the relative quantification was measured by using2^-△△Cr Ctmethod. Results The RT-PCR showed that the gray scaleratios of icaA in positive group and negative group of biofilm-forming were 0.96-1.38 and 0.89-1.56, respectively, the difference was not statistically significant （T=10.65, P=0.057）. The gray scale ratios of icaR genes in positive group and negative group ofbiofilm-forming were 0.79-1.24 and 0.80-1.36, respectively, the expression between the two groups were not statistically significant（T=14.62, P=0.479） . The mean rank and sum of ranks of icaA gene in biofilm positive bacteria group （16.35） were significantly higherthan those in biofilm negative group （10.65）, but the mean rank and sum of ranks of icaR gene in biofilm positive bacteria group（12.38） were significantly lower than those in biofilm negative bacteria group （14.62）. Real-time PCR showed that the expression oficaA gene in S. epidermidis in biofilm positive group（△CT=4.86） was 418.8 times of that in biofilm negative bacteria group（△CT=13.57） （t=61.890, P〈0.01）, while the expression of icaR gene in biofilm positive group （△CT=19.03） was only 1/145 of thatin negative group （△CT=11.85） （t=21.330, P〈0.01）. Conclusion icaA gene is positively related to the formation of biofilm in S.epidermidis, while icaR gene is negatively related to the formation of biofilm in S. epi
作者
朱娟
陈丽华
佘鹏飞
谭芮辰
王妍乐
伍勇
ZHU Juan;CHEN Lihua;SHE Pengfei;TAN Ruichen;WANG Yanle;WU Yong(Department of Laboratory Medicine,the Third Xiangya Hospital of Central South University,Changsha,Hunan 410013,Hunan,China)
出处
《湖南中医药大学学报》
CAS
2018年第6期619-623,共5页
Journal of Hunan University of Chinese Medicine
基金
湖南省自然科学基金(2015JJ2188
2015JJ3165)
