Extraction and Analysis of Extracellular Polymeric Substances: Comparison of Methods and Extracellular Polymeric Substance Levels in Salmonella pullorum SA 1685
Extraction and Analysis of Extracellular Polymeric Substances: Comparison of Methods and Extracellular Polymeric Substance Levels in Salmonella pullorum SA 1685
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DOI：
10.1089/ees.2008.0398
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发表时间：
2009-10-01
影响因子：
1.8
通讯作者：
Walker, Sharon L.
中科院分区：
文献类型：
--
作者：
Gong, Amy S.;Bolster, Carl H.;Walker, Sharon L.
利用冻干法、乙醇法和超声法提取鸡白痢沙门氏菌胞外聚合物（EPS），研究了其在人工地下水（AGW）中的产生和组成。进行了实验，以评估三种EPS提取方法的鲁棒性和每种方法对溶液离子强度（IS）和暴露持续时间的细微变化的敏感性。在含有10（-2.5）、10（-2）和10（-1.5）M IS的AGW中孵育0、6、12、18和24 h后，分别使用苯酚硫酸和Lowry方法通过糖和蛋白质分析进行EPS提取和分析。冻干和乙醇方法导致提取的EPS量大于超声处理方法（EPS质量/细胞），但这些方法在各种测试条件下提取的EPS的总量或水平波动较大。在各种实验条件之间进行了系统的比较和广泛的统计分析。据我们所知，这是第一次系统地比较利用沙门氏菌的EPS提取技术的研究。当我们研究了沙门氏菌SA 1685在模拟地下水条件下的相对EPS含量时，我们的结果提供了对每种方法用于检测模拟或真实的地下水生系统中悬浮的细菌的环境诱导变化的适用性的见解。
Extracellular polymeric substances (EPS) production and composition for Salmonella pullorum SA 1685 exposed to artificial groundwater (AGW) has been examined utilizing three EPS extraction methods: lyophilization, ethanol, and sonication. Experiments were carried out to evaluate the robustness of three EPS extraction methods and the sensitivity of each to subtle changes in solution ionic strength (IS) and duration of exposure. EPS extraction and analysis was conducted via sugar and protein analyses using the phenol sulfuric acid and Lowry methods, respectively, after 0-, 6-, 12-, 18-, and 24-h incubation times in AGW with 10(-2.5), 10(-2), and 10(-1.5) M IS. Lyophilization and ethanol methods resulted in a greater amount of EPS extracted than the sonication method (mass of EPS/cell), yet these methods fluctuated to a greater extent in the total amount-or level-of EPS extracted under the various test conditions. Systematic comparisons and extensive statistical analyses were conducted between the various experimental conditions. To our knowledge, this is the first study systematically comparing EPS extraction techniques utilizing Salmonella. As we investigated the relative EPS content in Salmonella SA1685 under conditions simulating groundwater, our results provide insight into the suitability of each method for detection of environmentally induced changes in bacteria suspended in simulated or real subsurface aquatic systems.