Vadillo-Rodríguez Virginia, Busscher Henk J, Norde Willem, de Vries Joop, van der Mei Henny C
Department of Biomedical Engineering, University of Groningen, Antonius Deusinglaan 1, 9713 AV Groningen, The Netherlands.
J Colloid Interface Sci. 2004 Oct 1;278(1):251-4. doi: 10.1016/j.jcis.2004.05.045.
Initial bacterial adhesion is considered to be reversible, but over time the adhesive bond between a bacterium and a substratum surface may strengthen, turning the process into an irreversible state. Microbial desorption has been studied in situ in controlled flow devices as a function of the organisms resident time on the surface (J. Colloid Interface Sci. 164 (1994) 355). It appeared that desorption of Streptococcus thermophilus decreased strongly within approximately 50 s after initial adhesion due to bond aging. In this paper, bond aging between the S. thermophilus cell surface and the silicon nitride tip of an AFM (atomic force microscope) is corroborated microscopically and related to the macroscopic, residence time-dependent desorption of the organism under flow. AFM indicated bond strengthening between the tip and the cell surface within 100 s of contact, which is on the same order of magnitude as bond aging inferred from residence time-dependent desorption. Comparison of the interaction energies derived from AFM and macroscopic desorption indicate that bond strengthening arises as a result of multiple attachments of extracellular polymeric substances to a substratum surface.
初始细菌黏附被认为是可逆的，但随着时间的推移，细菌与基质表面之间的黏附键可能会增强，从而使该过程转变为不可逆状态。微生物解吸已在可控流动装置中进行原位研究，作为生物体在表面停留时间的函数（《胶体与界面科学杂志》164 (1994) 355）。结果表明，由于键老化，嗜热链球菌在初始黏附后约50秒内解吸强烈下降。在本文中，嗜热链球菌细胞表面与原子力显微镜（AFM）的氮化硅尖端之间的键老化通过显微镜得到证实，并与该生物体在流动条件下宏观的、依赖停留时间的解吸相关。原子力显微镜显示，在接触100秒内，尖端与细胞表面之间的键增强，这与从依赖停留时间的解吸推断出的键老化处于同一数量级。从原子力显微镜和宏观解吸得出的相互作用能的比较表明，键增强是细胞外聚合物多次附着到基质表面的结果。
