血链球菌细菌素对牙龈卟啉单胞菌形貌及力学性质的影响

Effect of Streptococcus Sanguis Bacteriocin on Morphology and Mechanical Properties of Porphyromonas Gingivalis

目的:研究血链球菌细菌素(简称血链素)对牙龈卟啉单胞菌(Porphyromonas gingivalis,P.g)形貌特征及力学性质的影响。方法:1)复苏、传代并鉴定血链球菌标准菌株ATCC10556、牙龈卟啉单胞菌标准菌株ATCC33277。2)将血链球菌低温高速离心、细胞破碎等方法提取血链素,使之作用于P.g,于37℃厌氧培养48h。3)采用原子力显微镜(AFM)的接触模式,观察血链素作用前后P.g菌体的形貌变化。4)利用AFM测定血链素作用前后P.g的力-距离曲线,并计算黏附力及杨氏模量。结果:1)通过AFM的观察:P.g在血链素的作用下,菌体直径缩小、平均粗糙度及平均峰高度增加(P<0.05)。2)通过AFM的观察:血链素作用后,P.g的黏附力、杨氏模量显著降低(P<0.001)。正常P.g的黏附力平均值为(0.70±0.10)nN、杨氏模量平均值为(5.54±0.16)MPa;经血链素作用后P.g的黏附力平均值为(0.50±0.10)nN、杨氏模量平均值为(3.97±0.64)MPa。结论:1)血链素可引起牙龈卟啉单胞菌形貌特征发生改变。2)血链素可导致牙龈卟啉单胞菌的黏附力及杨氏模量降低。

Objective：To study the effects of streptococcus sanguis bacteriocins on the surface morphology and the mechanical properties of porphyromonas gingivalis（P.g）.Methods：Standard strains ATCC10556 and ATCC33277were recovered and extended.Streptococcus sanguis bacteriocins was extracted by low temperature high-speed centrifugation and ultrasonic broken.Streptococcus sanguis bacteriocins was affected with P.g at 37℃ and anaerobic cultured for 48 h.Atomic force microscope（AFM）was used to observe the microstructure of Streptococcus sanguis bacteriocins on P.g.Through the force-distance curve,the Young＇s modulus and adhesion of Streptococcus sanguis bacteriocins on P.g were calculated.Results：AFM showed that Streptococcus sanguis bacteriocins could reduce the diameter of P.g,rise the average roughness and average peak height（P〈0.05）.After Streptococcus sanguis bacteriocins on P.g,the adhesion and the Young＇s modulus of P.g reduced significantly（P〈0.001）.The adhesion and the Young＇s modulus of P.g were（0.7±0.1）nN and（5.54±0.16）Mpa.After Streptococcus sanguis bacteriocins on P.g,the adhesion and the Young＇s modulus of P.g were 0.50±0.1nN and 3.97±0.64 Mpa.Conclusion：Streptococcus sanguis bacteriocins can change the morphology of P.g and reduce the adhesion and the Young＇s modulus of P.g.