The lipidome of the pellicle and the role of lipids for the dynamic process of initial biofilm formation in situ.

在口腔内生物粘附过程的第一阶段，发生膜层的形成，最终覆盖口腔的所有表面。膜是口腔生物膜形成的关键决定因素，含有相当比例的脂质。到目前为止，原位膜的脂质组成尚未被详细表征，然而，疏水相互作用对粘附生物膜形成的重要性已得到普遍承认。因此，本临床实验研究旨在研究细胞膜脂质组的组成、分布及其对表面物理化学相互作用的影响。特别的重点将放在通过高效液相色谱质谱/质谱（磷脂，糖脂，甘油三酯，胆固醇）的功能相关的膜组分的定量和表征。此外，还将研究不同疏水漱口剂对原位膜的脂质组成和超微结构的影响。通过透射电子显微镜检查细胞膜的超微结构，通过免疫电子显微镜技术和质谱成像评估细胞膜中的脂质分布。最后，本研究的主要目的是更全面地了解初始生物粘附过程的分子机制，因此，细菌生物膜的形成特别强调亲脂成分和疏水表面相互作用。所获得的结果将揭示关于脂质组分对口腔生物膜形成的定性和定量重要性的新见解，这可能也会转移到一般的生物粘附过程中。

In the first stage of intraoral bioadhesion processes the formation of a pellicle layer occurs, eventually covering all surfaces of the oral cavity. The pellicle is a crucial determinant of oral biofilm formation and contains a considerable proportion of lipids. So far, the lipid composition of the in situ pellicle has not been characterized in detail, however, the importance of hydrophobic interactions for the formation of an adherent biofilm is generally acknowledged. Therefore, the requested clinical experimental study aims to examine the lipidome of the pellicle with respect to its composition, distribution and impact on physicochemical surface interactions. A special focus will be placed on the quantification and characterization of functionally relevant pellicle components by HPLC MS/MS (phospholipids, glycolipids, triglycerides, cholesterol). Furthermore different hydrophobic mouthrinses will be examined for their effect on the lipid composition and the ultrastructure of the in situ pellicle. The ultrastructure of the pellicle will be examined by transmission electron microscopy, the distribution of the lipids in the pellicle will be evaluated by immuno electronmicroscopical techniques and by mass spectrometric imaging. Finally, the primary objective of this study would be to gain a more comprehensive picture of the molecular mechanisms underlying initial bioadhesion processes and, as a result, bacterial biofilm formation with particular emphasis on the lipophilic components and hydrophobic surface interactions. The obtained results will reveal new insights about the qualitative and quantitative importance of the lipid fractions for the oral biofilm formation which, potentially, could also be transferred to bioadhesion processes in general.