Identification of bacterial populations in drinking water using 16S rRNA-based sequence analyses

Area of Science:

• Microbiology
• Environmental Science
• Molecular Biology

Background:

• Intracellular RNA is unstable, making RNA-based methods suitable for studying active microbial fractions in environmental samples.
• Previous studies suggest RNA-based approaches for analyzing microbial communities in various matrices.

Purpose of the Study:

• To identify bacterial populations in drinking water using 16S ribosomal RNA (rRNA)-based clone libraries.
• To understand the molecular diversity and temporal dynamics of bacterial communities in drinking water.

Main Methods:

• Concentration of bacterial communities from tap water using hollow-fiber ultrafiltration.
• Extraction of total RNA and development of 16S rRNA-based clone libraries.
• Phylogenetic and diversity analyses of 1231 partial 16S rRNA gene sequences.

Main Results:

• Difficult-to-classify bacterial sequences were predominant (57.6%), often related to previous drinking water studies.
• Proteobacteria, cyanobacteria, Actinobacteria, Bacteroidetes, and Planctomycetes were also identified.
• Bacterial membership changed over time, although overall diversity remained consistent across months.

Conclusions:

• The identified bacterial groups, including unclassified sequences, are potentially active members of drinking water microbial communities.
• The study enhances understanding of drinking water microbial diversity and population dynamics.
• Findings provide a sequence foundation for developing molecular assays targeting active drinking water bacteria.