Presence of Legionella spp. in cooling towers: the role of microbial diversity, Pseudomonas, and continuous chlorine application

WATER RESEARCH

卷:169

Article

Paranjape, Kiran¹  Bedard, Emilie^1,2  Whyte, Lyle G.¹  Ronholm, Jennifer^3,4  Prevost, Michele²  Faucher, Sebastien P.¹ 

[1] McGill Univ, Fac Agr & Environm Sci, Dept Nat Resource Sci, Ste Anne De Bellevue, PQ, Canada

[2] Polytech Montreal, Dept Civil Engn, Montreal, PQ, Canada

[3] McGill Univ, Fac Agr & Environm Sci, Dept Food Sci & Agr Chem, Ste Anne De Bellevue, PQ, Canada

[4] McGill Univ, Fac Agr & Environm Sci, Dept Anim Sci, Ste Anne De Bellevue, PQ, Canada

关键词: Microbiome;    16S rRNA gene targeted amplicon sequencing;    Cooling towers;    Legionella pneumophila;    Pseudomonas;    Chlorine;   

DOI  :  10.1016/j.watres.2019.115252

来源: Elsevier

【 摘 要 】

Legionnaires' disease (LD) is a severe pneumonia caused by several species of the genus Legionella, most frequently by Legionella pneumophila. Cooling towers are the most common source for large community-associated outbreaks. Colonization, survival, and proliferation of L. pneumophila in cooling towers are necessary for outbreaks to occur. These steps are affected by the chemical and physical parameters of the cooling tower environment. We hypothesize that the bacterial community residing in the cooling tower could also affect the presence of L. pneumophila. A 16S rRNA gene targeted amplicon sequencing approach was used to study the bacterial community of cooling towers and its relationship with the Legionella spp. and L. pneumophila communities. The results indicated that the water source shaped the bacterial community of cooling towers. Several taxa were enriched and positively correlated with Legionella spp. and L. pneumophila. In contrast, Pseudomonas showed a strong negative correlation with Legionella spp. and several other genera. Most importantly, continuous chlorine application reduced microbial diversity and promoted the presence of Pseudomonas creating a non-permissive environment for Legionella spp. This suggests that disinfection strategies as well as the resident microbial population influences the ability of Legionella spp. to colonize cooling towers. (C) 2019 Elsevier Ltd. All rights reserved.

【 授权许可】

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