Crull Suzanne, Hammer Emlyn, Mann Allison E, O'Connell Lauren M, Soule Ashlyn, Griffith Elizabeth, Blouin Thomas, Brigmon Robin L, Richards Vincent P
Department of Biological Sciences, Clemson University, Clemson, South Carolina, USA.
Department of Anthropology, University of Wyoming, Laramie, Wyoming, USA.
Environ Microbiol Rep. 2025 Aug;17(4):e70132. doi: 10.1111/1758-2229.70132.
Legionella is a genus of environmental bacteria containing pathogenic species such as Legionella pneumophila that are responsible for Legionnaires' disease, a potentially fatal respiratory infection. Disease aetiology can involve Legionella replication intracellularly within protists and this study aimed to characterise the Legionella-protist relationship to develop novel outbreak prevention targets. Water and sediment samples were collected from a water-cooling tower in South Carolina over a 6-month period. Concomitantly, multiple environmental parameters were recorded. Bacterial and eukaryotic communities were characterised using 16S rRNA gene V4 region and a 252 bp fragment of 18S rRNA gene, respectively. Co-occurrence network analyses were performed to elucidate Legionella-protist correlations through time. We found that Legionella correlated with different protists as the seasons progressed. Acanthamoeba correlated with Legionella in early spring followed by Vannella and Korotnevella in late spring and early summer, and were joined by Echinamoeba in mid-summer. Vannella and Acanthamoeba are known potential hosts for Legionella, while Korotnevella is a potential undocumented host. Of the environmental parameters, temperature showed strong correlation with protists genera, suggesting that Legionella abundance was driven by temperature-dependent protist availability. Our results highlight ecological shifts that are associated with elevated Legionella levels, which offers potential targets to help predict and prevent disease outbreaks.
军团菌是一类环境细菌，包含诸如嗜肺军团菌等致病物种，这些物种可引发军团病，这是一种可能致命的呼吸道感染。疾病病因可能涉及军团菌在原生生物细胞内的复制，本研究旨在表征军团菌与原生生物的关系，以开发新的疫情预防靶点。在6个月的时间里，从南卡罗来纳州的一个水冷塔采集了水和沉积物样本。同时，记录了多个环境参数。分别使用16S rRNA基因V4区域和18S rRNA基因的252bp片段对细菌和真核生物群落进行了表征。通过共现网络分析来阐明军团菌与原生生物随时间的相关性。我们发现，随着季节的推移，军团菌与不同的原生生物相关。早春时棘阿米巴与军团菌相关，晚春和初夏时分别是梵内拉属和科罗特涅夫氏菌属，仲夏时棘阿米巴与它们一起出现。梵内拉属和棘阿米巴是已知的军团菌潜在宿主，而科罗特涅夫氏菌属是一个潜在的未被记录的宿主。在环境参数中，温度与原生生物属显示出强烈的相关性，这表明军团菌的丰度受温度依赖的原生生物可利用性驱动。我们的结果突出了与军团菌水平升高相关的生态变化，这为帮助预测和预防疾病爆发提供了潜在靶点。
