10-23脱氧核酶抑制细菌β-内酰胺酶基因表达的实验研究

10-23 deoxyribozymes inhibit the expression of bacterial β-lactamase gene

目的:观察10-23脱氧核酶对细菌β-内酰胺酶基因表达的抑制作用。方法:设计并合成针对细菌β-内酰胺酶SHV-5基因的10-23脱氧核酶、反义寡核苷酸和无关对照寡核苷酸,采用电穿孔法将其分别导入表达β-内酰胺酶SHV-5的大肠杆菌中,观察耐药菌在导入脱氧核酶后,在含β-内酰胺类抗菌素培养基中的生长活力及β-内酰胺酶表达量的变化。结果:10-23脱氧核酶导入表达blaSHV-5的大肠杆菌后,在含头孢他啶的培养基中大肠杆菌的生长活力明显低于反义寡核苷酸和无关对照DNA转化的大肠杆菌,导入脱氧核酶的大肠杆菌其β-内酰胺酶表达量也明显低于反义寡核苷酸和无关对照DNA转化的大肠杆菌。结论:10-23脱氧核酶能特异性地抑制细菌β-内酰胺酶基因表达。

AIM： To study the inhibitory effects of 10 - 23 dcoxyribozyme （ 10 - 23 DRz） on Escherichia coli β-- lactamase gene expression. METHODS： According to the gene sequence of Escherichia coli β- lactamase gene blashv- 5, 10- 23 DRz and antisense oligonuclcotides （As- ODN） were designed and synthesized. 10- 23 DRz, As- ODN or control oligonucleotides were respectively introduced into Escherichia coli by the method of electroporation. Following dectroporation, bacterial viability in liquid medium contained ceftazidime was detected, bacterial β- lactamase expression was analysed by using IEF- PAGE and the β - lactamase band was measured with gel documentation - analyzing system. RESULTS： A600 in 10 - 23 DRz transfected Escherichia coli was lower compared with that in As- ODN transfected Escherichia coli （ P 〈 0.05）. Bacterial β- lactamase expression in 10- 23 DRz transfected Escherichia coli was also lower compared with that in As - ODN tmasfected Escheruichia coli （ P 〈 0.01）. CONCLUSION： 10- 23 DRz specifidy inhibits bacterial β- lactamase gene expression.