The Key Laboratory of Water and Sediment Sciences, Ministry of Education, State Environmental Protection Key Laboratory of All Material Fluxes in River Ecosystems, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, P. R. China.
Biomedical Pioneering Innovation Center, School of Life Sciences, Peking University, Beijing 100871, P. R. China.
Environ Sci Technol. 2021 Apr 20;55(8):4964-4973. doi: 10.1021/acs.est.0c08712. Epub 2021 Mar 26.
The effects of flagella and their properties on bacterial transport and deposition behaviors were examined by using four types of () with or without flagella, as well as with normal or sticky flagella. Packed column, quartz crystal microbalance with dissipation, visible parallel-plate flow chamber system, and visible flow chamber packed with porous media system were employed to investigate the deposition mechanisms of bacteria with different properties of flagella. We found that the presence of flagella favored deposition onto quartz sand/silica surfaces. Moreover, by changing the porous media porosity and directly observing the bacterial deposition process, local sites with high roughness, narrow flow channels, and grain-to-grain contacts were found to be the major sites for bacterial deposition. Particularly, flagella could help bacteria swim near and then deposit at these sites. In addition, we found that due to the stronger adhesive forces, sticky flagella could further enhance bacterial deposition onto quartz sand/silica surfaces. Elution experiments indicated that flagella could help bacteria attach onto sand surfaces more irreversibly. Clearly, flagella and their properties would have obvious impacts on the transport/deposition behaviors of bacteria in porous media.
利用带有或不带有鞭毛且具有正常或粘性鞭毛的四种类型的 ()，研究了鞭毛及其特性对细菌输运和沉积行为的影响。采用填充柱、石英晶体微天平耗散、可见平行板流动室系统和多孔介质填充可见流动室系统研究了具有不同鞭毛特性的细菌的沉积机制。我们发现鞭毛的存在有利于细菌在石英砂/二氧化硅表面的沉积。此外，通过改变多孔介质的孔隙率并直接观察细菌的沉积过程，发现具有高粗糙度、狭窄流道和颗粒间接触的局部位置是细菌沉积的主要位置。特别是，鞭毛可以帮助细菌游近这些位置，然后在这些位置沉积。此外，我们发现由于粘性鞭毛具有更强的粘附力，因此可以进一步增强细菌在石英砂/二氧化硅表面的沉积。洗脱实验表明，鞭毛可以帮助细菌更不可逆地附着在砂表面上。显然，鞭毛及其特性会对细菌在多孔介质中的输运/沉积行为产生明显影响。
