Bacterial Community Structure in the Drinking Water Microbiome Is Governed by Filtration Processes

Department of Civil and Environmental Engineering, University of Michigan, USA.
Environmental Science & Technology (Impact Factor: 5.48). 07/2012; 46(16):8851-9. DOI: 10.1021/es302042t
Source: PubMed

ABSTRACT The bacterial community structure of a drinking water microbiome was characterized over three seasons using 16S rRNA gene based pyrosequencing of samples obtained from source water (a mix of a groundwater and a surface water), different points in a drinking water plant operated to treat this source water, and in the associated drinking water distribution system. Even though the source water was shown to seed the drinking water microbiome, treatment process operations limit the source water's influence on the distribution system bacterial community. Rather, in this plant, filtration by dual media rapid sand filters played a primary role in shaping the distribution system bacterial community over seasonal time scales as the filters harbored a stable bacterial community that seeded the water treatment processes past filtration. Bacterial taxa that colonized the filter and sloughed off in the filter effluent were able to persist in the distribution system despite disinfection of finished water by chloramination and filter backwashing with chloraminated backwash water. Thus, filter colonization presents a possible ecological survival strategy for bacterial communities in drinking water systems, which presents an opportunity to control the drinking water microbiome by manipulating the filter microbial community. Grouping bacterial taxa based on their association with the filter helped to elucidate relationships between the abundance of bacterial groups and water quality parameters and showed that pH was the strongest regulator of the bacterial community in the sampled drinking water system.

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Available from: Lutgarde Raskin, Jun 24, 2014
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    • "It does not require labelled primers/nucleotides or gel electrophoresis and allows a large number of samples to be pooled (Ronaghi, 2001; Fakruddin and Chowdhury, 2012). This technique has recently been applied for the identification of species present in water during treatment (Wakelin et al., 2011; Pinto et al., 2012) and distribution (Henne et al., 2008; Hong et al., 2010; Hwang et al., 2012; Lin et al., 2013; Liu et al., 2013a; Lautenschlager et al., 2013). The studies using pyrosequencing have proved the value of identifying bacterial groups, for the evaluation of e.g. "
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    • "Within Proteobacteria, α-Proteobacteria was the most dominant class in each water sample, followed by β-, γ-and δsubdivisions (Fig. 1), which is consistent with previous study (Kwon et al., 2011) revealing that α-subdivision was the more abundant than other classes of Proteobacteria in drinking water based on pyrosequencing. However, Pinto et al. (2012) showed that β-Proteobacteria (40%) was more abundant than "
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    • "This is particularly relevant for drinking water systems where the water is distributed without final disinfection or residual disinfectants (Lautenschlager et al., 2013; Vital et al., 2012). Until recently, the number of studies addressing the composition of microbial communities and their function within drinking water treatment plants was limited (e.g., Lin et al., 2014; Bai et al., 2013; Pinto et al., 2012; White et al., 2012). With the development of next generation DNA sequencing methods, it is feasible to effectively profile the change of microbial communities throughout a comprehensive water treatment plant and to understand how each treatment step influences the microbial community structure, biomass density and water quality. "
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