变形链球菌生物膜对抗菌剂敏感性的研究

Susceptibility of Streptococcus mutans biofilm to antimicrobial agents

目的用激光共聚焦扫描显微镜(CLSM)观察变形链球菌生物膜对抗菌剂的敏感性。方法在体外形成变形链球菌生物膜,用不同浓度青霉素分别作用于生物膜3h。生物膜进行荧光染色,CLSM扫描观察。结果变形链球菌生物膜在青霉素浓度为2500mg/L时作用3h,未被完全杀死,随着药物浓度增加,生物膜对青霉素的抵抗力逐渐减弱。结论变形链球菌生物膜比浮游状态变形链球菌对青霉素具有更高的抵抗力,提示临床应该以新的思路来研究控制生物膜造成的感染。

Objective To investigate the susceptibility of Streptococcus mutans （S. mutans） biofilms to antimicrobial agent by confocal laser scanning microscopy （CLSM）. Methods S. mutans biofilms formed in vitro on glass slice were acted on with penicillin of different concentrations for 3 h. Then these biofilms were stained by fluorescence and were observed by CLSM. The bacterial density and vitability of biofilms were recorded. Results When S. mutans biofilms were exposed to penicillin of 2 500 mg/L for 3 h, it was not completely killed. The higher the concentration of penicillin was, the weaker the biofilms against penicillin. Conclusions Compared with planktonic S. mutans, S. mutans biofilms produced stronger resistance to penicillin. It suggests that we should find new strategies to control the infection caused by biofilm in clinic.