Department of Applied Sciences, University of the West of England, Coldharbour Lane, Frenchay, Bristol BS16 1QY, United Kingdom.
Antimicrob Agents Chemother. 2011 Nov;55(11):5214-20. doi: 10.1128/AAC.00489-11. Epub 2011 Aug 29.
Traditional microbiological techniques are used to provide reliable data on the rate and extent of kill for a range of biocides. However, such techniques provide very limited data regarding the initial rate of kill of fast-acting biocides over very short time domains. This study describes the application of a recombinant strain of Escherichia coli expressing the Photorhabdus luminescens lux operon as a whole-cell biosensor. Light emission is linked directly to bacterial metabolism; therefore, by monitoring light output, the impact of fast-acting biocides can be assessed. Electrochemically activated solutions (ECASs), bleach, Virkon, and ethanol were assessed at three concentrations (1%, 10%, 80%) in the presence of organic soiling. Over a 2-s time course, 80% ECAS produced the greatest reduction in light output in the absence of organic load but was strongly inhibited by its presence. Eighty percent ethanol outperformed all tested biocides in the presence of organic soil. Bleach and Virkon produced similar reductions in bioluminescence at matched concentrations within the time course of the assay. It was also demonstrated that the assay can be used to rapidly assess the impact of organic soiling. The use of bioluminescent bacteria as whole-cell bioreporters allows assessment of the relative efficacies of fast-acting biocides within milliseconds of application. The assay can be used to investigate activity over short or extended time domains to confirm complete metabolic inhibition of the bioreporter. Moreover, the assay may enable further elucidation of their mechanism of action by allowing the investigation of activity over time domains precluded by traditional microbiology.
传统的微生物学技术用于为一系列杀生物剂的杀灭速率和范围提供可靠的数据。然而，此类技术对于快速作用的杀生物剂在非常短的时间域内的初始杀灭速率仅提供非常有限的数据。本研究描述了表达 Photorhabdus luminescens lux 操纵子的重组大肠杆菌菌株作为全细胞生物传感器的应用。光发射与细菌代谢直接相关；因此，通过监测光输出，可以评估快速作用的杀生物剂的影响。电化学激活溶液 (ECAS)、漂白剂、Virkon 和乙醇在存在有机污垢的情况下，在三个浓度（1%、10%、80%）下进行了评估。在 2 秒的时间过程中，在没有有机负荷的情况下，80%的 ECAS 产生了最大的光输出减少，但强烈受到其存在的抑制。在存在有机土壤的情况下，80%的乙醇在所有测试的杀生物剂中表现最佳。在检测时间范围内，漂白剂和 Virkon 在匹配浓度下产生了相似的生物发光减少。还证明该测定法可用于快速评估有机污垢的影响。使用发光细菌作为全细胞生物报告器可以在杀生物剂施加后的几毫秒内评估快速作用的杀生物剂的相对功效。该测定法可用于在短时间或长时间内研究活性，以确认生物报告器的完全代谢抑制。此外，该测定法可以通过允许在传统微生物学排除的时间段内研究活性来进一步阐明其作用机制。
