The description of microorganisms inhabiting drinking water distribution systems has commonly
been performed using techniques that are biased towards easy to culture bacterial populations. As
most environmental microorganisms cannot be grown on artificial media, the understanding of
the microbial community structure of drinking water is very limited. To circumvent some of the
problems associated with culture-based techniques, sequence analysis of 16S rRNA gene clone
libraries was used in this study. Genomic DNA was extracted from bulk phase water from
sampling sites within the distribution systems (WDS), and used to develop 16S rRNA gene
clone libraries. Water samples were collected from areas within the distribution system fed by
two distinct raw water sources. Over 2300 16S rDNA clones were analyzed in this study from a
total of 31 different sites. Phylogenetic analyses showed that a-Proteobacteria and Actinobacteria
represented more than 90% of the total clones examined. In general, similar bacterial groups
were observed in sites receiving groundwater and surface water sources suggesting that
chlorination is an important selective force in shaping up the overall microbial community
structure. While the communities were similar at the general bacterial group, there were some
differences at finer phylogenetic levels. This is important as it suggests that differences in the
sources and treatment technologies could select for different populations. Since more than half of
the clones were associated with yet to be cultured bacteria, and in many cases with novel
bacterial groups, the results further substantiate the need for the development of culture-independent methods to better identify drinking water and to study their in situ spatial temporal dynamics. Includes 36 references, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 1.1 MB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 12 |
| Published : | 11/01/2009 |
