细菌共聚合是一种高度特异性的细胞-细胞相互作用,在口腔细菌中有很好的记录,并涉及共聚集菌株的细胞表面的特定特征。然而,对促进水生系统共聚集机制的理解仍然有限。这个差距对于解决至关重要,鉴于共聚合对多物种生物膜形成的广泛影响,水质,工程系统的性能,和多样化的生物技术应用。因此,本研究旨在全面表征共聚集菌株Delftiaacidovorans005P的细胞表面,与饮用水隔离,除了非共聚集菌株之外,D.酸多兰009P。通过分析同一物种的两个菌株,我们的目的是确定导致菌株005P共聚集能力的因素。为了实现这一点,我们采用了物理化学表征的组合,傅里叶变换红外光谱(FTIR),和先进的成像技术[透射电子显微镜和低温电子断层扫描(cryo-ET)]。共聚集应变(005P)表现出较高的表面疏水性,负表面电荷,和细胞表面和共粘附能比非共聚集应变(009P)。通过FTIR对细菌表面的化学表征揭示了细微的差异,特别是在与蛋白质的碳水化合物和磷酸二酯/酰胺III相关的光谱区域(分别为860-930cm-1和1212-1240cm-1)。Cryo-ET强调了菌株之间菌毛结构的显着差异,例如长度的变化,频率,和安排。005P菌株中的菌毛,被鉴定为菌毛样粘附素,作为共同聚集的关键中介。通过整合物理化学分析和高分辨率成像技术,这项研究最终将D.acidovorans005P的共聚集能力与其独特的菌毛特性联系起来,强调它们在水生环境中微生物共聚的关键作用。
Bacterial coaggregation is a highly specific type of cell-cell interaction, well-documented among oral bacteria, and involves specific characteristics of the cell surface of the coaggregating strains. However, the understanding of the mechanisms promoting coaggregation in aquatic systems remains limited. This gap is critical to address, given the broad implications of coaggregation for multispecies biofilm formation, water quality, the performance of engineered systems, and diverse biotechnological applications. Therefore, this study aims to comprehensively characterize the cell surface of the coaggregating strain Delftia acidovorans 005P, isolated from drinking water, alongside a non-coaggregating strain, D. acidovorans 009P. By analyzing two strains of the same species, we aim to identify the factors contributing to the coaggregation ability of strain 005P. To achieve this, we employed a combination of physicochemical characterization, Fourier-transform infrared spectroscopy (FTIR), and advancing imaging techniques [transmission electron microscopy and cryo-electron tomography (cryo-ET)]. The coaggregating strain (005P) exhibited higher surface hydrophobicity, negative surface charge, and cell surface and co-adhesion energies than the non-coaggregating strain (009P). The chemical characterization of bacterial surfaces through FTIR revealed subtle differences, particularly in spectral regions linked to carbohydrates and phosphodiesters/amide III of proteins (860-930 cm-1 and 1212-1240 cm-1, respectively). Cryo-ET highlighted significant differences in pili structures between the strains, such as variations in length, frequency, and arrangement. The pili in the 005P strain, identified as pili-like adhesins, serve as key mediators of coaggregation. By integrating physicochemical analyses and high-resolution imaging techniques, this study conclusively links the coaggregation ability of D. acidovorans 005P to its unique pili characteristics, emphasizing their crucial role in microbial coaggregation in aquatic environments.