Effect of temperature conditions on the growth of Legionella species in complex biological systems for wastewater treatment

温度条件对废水处理复杂生物系统中军团菌生长的影响

• 批准号: 520464014
• 负责人: Professorin Dr. Regina Maria de Oliveira Barros Nogueira
• 金额: --
• 依托单位: Institut für Siedlungswasserwirtschaft und Abfalltechnik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/520464014?language=en
• 关键词: Effect; temperature; conditions; growth; Legionella

Pathogenic Legionella spp., like Legionella pneumophila, can cause Legionnaire’s disease, a severe lung infection with a mortality of 5-10%. It is transmitted by the inhalation of contaminated aerosols from man-made water systems, such as wastewater treatment plants. Cases of Legionnaires’ disease increased in Europe by 65 % from 2015 to 2019. Legionnaires’ disease cases originating from wastewater treatment plants are expected to increase due to increased wastewater reuse applications and Climate Change. The latter in particular will increase wastewater temperatures, affecting also the microbial composition of wastewaters. To the best of our knowledge, a solution to prevent the multiplication of Legionella in wastewater treatment plants with warm wastewater temperatures (>23°C) is not available due to the lack of fundamental research. The objective of this proposal is to define the temperature conditions favouring the growth of pathogenic Legionella spp. from wastewater treatment plants, considering constant and dynamic temperature conditions.Isolates obtained from treated wastewater or activated sludge of five different wastewater treatment plants, treating industrial warm wastewaters, will be cultivated at five different temperatures between 20 °C and 40 °C. To test the effect of dynamic temperature conditions the temperature will be increased by 5 °C in a short time in the middle of the exponential growth phase. The Legionella’s growth parameters will be compared before and after the perturbation. A fast temperature increase of 5 °C was chosen according to our experience in monitoring Legionella spp. in wastewater treatment plants. The environmental Legionella isolates will be obtained, using the cultivation method. The affiliation of the environmental isolates and the Legionella spp. diversity in the biological stage will be analysed by genus-specific next-generation sequencing. Isolates for the temperature experiment will be selected covering the core Legionella community, present in all five wastewater treatment plants, and the unique phylotypes, only present in specific wastewater treatments plants.The integration of the results coming from the wastewater/wastewater treatment plant characterisation, the Legionella diversity and the temperature-dependent growth of Legionella environmental isolates from wastewater will advance our understanding of the role of wastewater treatment plants as an ecological niche for the growth of Legionella spp. . Our findings may be used to improve Legionella monitoring in wastewater treatment plants and to support the practitioners in the development of strategies to manage with sudden changes in temperature in wastewater treatment and reclamation facilities.

像嗜肺军团菌一样，致病性军团菌可引起军团病，这是一种严重的肺部感染，死亡率为5%-10%。它通过吸入污水处理厂等人造水系统中受污染的气雾剂传播。从2015年到2019年，欧洲退伍军人症病例增加了65%。由于废水再利用应用的增加和气候变化，来自废水处理厂的退伍军人症病例预计将增加。后者尤其会提高废水温度，还会影响废水中的微生物成分。据我们所知，由于缺乏基础研究，在污水温度较高(&gt；23℃)的污水处理厂中，无法找到防止军团菌繁殖的解决方案。这项建议的目的是确定有利于致病军团菌生长的温度条件。来自污水处理厂，考虑恒温和动态温度条件。从处理工业温暖废水的五个不同污水处理厂的废水或活性污泥中获得的分离株将在20°C到40°C之间的五个不同温度下培养，以测试动态温度条件的影响，在指数生长期中期的短时间内温度将上升5°C。我们将比较扰动前后军团菌的生长参数。根据我们监测军团菌的经验，选择了5℃的快速升温。在污水处理厂。采用这种培养方法，将获得环境中的军团菌。环境菌株与军团菌的联系。生物阶段的多样性将通过特定属的下一代测序进行分析。温度实验的菌株将涵盖所有五个污水处理厂的核心军团菌群落，以及仅存在于特定污水处理厂的独特的种型。综合来自废水/污水处理厂的特征、军团菌多样性和污水中军团菌环境分离株的温度依赖生长的结果，将加深我们对污水处理厂作为军团菌生长的生态位的作用的理解。。我们的研究结果可用于改进污水处理厂的军团菌监测，并支持从业者制定应对污水处理和回收设施温度突然变化的策略。