1Laboratory of Microbiology, Wageningen University & Research, Stippeneng 4, 6708 WE Wageningen, The Netherlands.
2Wetsus, European Centre of Excellence for Sustainable Water Technology, Oostergoweg 9, 8911 MA Leeuwarden, The Netherlands.
NPJ Biofilms Microbiomes. 2019 Jan 25;5(1):6. doi: 10.1038/s41522-018-0074-1. eCollection 2019.
Membrane filtration systems are widely applied for the production of clean drinking water. However, the accumulation of particles on synthetic membranes leads to fouling. Biological fouling (i.e., biofouling) of reverse osmosis and nanofiltration membranes is difficult to control by existing cleaning procedures. Improved strategies are therefore needed. The bacterial diversity on fouled membranes has been studied, especially to identify bacteria with specialized functions and to develop targeted approaches against these microbes. Previous studies have shown that are initial membrane colonizers that remain dominant while the biofilm develops. Here, we characterized 21 isolates, obtained from six different fouled membranes, to determine which physiological traits could contribute to colonization of membrane surfaces. Their growth conditions ranged from temperatures between 8 and 42 C, salinity between 0.0 and 5.0% w/v NaCl, pH from 4 and 10, and all isolates were able to metabolize a wide range of substrates. The results presented here show that membrane isolates share many features that are uncommon for other members of the family: all membrane isolates are motile and their tolerance for different temperatures, salt concentrations, and pH is high. Although relative abundance is an indicator of fitness for a whole group, for the it does not reveal the specific physiological traits that are required for membrane colonization. This study, therefore, adds to more fundamental insights in membrane biofouling.
膜过滤系统广泛应用于清洁饮用水的生产。然而，颗粒在合成膜上的积累会导致膜污染。反渗透和纳滤膜的生物污染（即生物结垢）很难通过现有的清洗程序来控制。因此，需要改进策略。已经研究了污染膜上的细菌多样性，特别是为了识别具有特殊功能的细菌，并针对这些微生物开发有针对性的方法。以前的研究表明， 是初始的膜定殖者，在生物膜发育过程中保持优势。在这里，我们对 21 个从六个不同污染膜中获得的分离物进行了表征，以确定哪些生理特征可能有助于膜表面的定殖。它们的生长条件范围从 8 到 42°C 的温度、0.0 到 5.0%w/v NaCl 的盐度、4 到 10 的 pH 值，所有分离物都能够代谢广泛的底物。这里呈现的结果表明， 膜分离物具有许多不常见的特征，这些特征对于 家族的其他成员来说并不常见：所有膜分离物都是运动的，它们对不同的温度、盐浓度和 pH 值的耐受性都很高。虽然相对丰度是整个群体适应性的一个指标，但对于 来说，它并不能揭示出膜定殖所需的特定生理特征。因此，这项研究增加了对膜生物污染的更基本的了解。
