Pyrosequencing Analysis of the Bacterial Community in Drinking Water Wells

Abstract

Wells used for drinking water often have a large biomass and a high bacterial diversity. Current technologies are not always able to reduce the bacterial population, and the threat of pathogen proliferation in drinking water sources is omnipresent. The environmental conditions that shape the microbial communities in drinking water sources have to be elucidated, so that pathogen proliferation can be foreseen. In this work, the bacterial community in nine water wells of a groundwater aquifer in Northern Mexico were characterized and correlated to environmental characteristics that might control them. Although a large variation was observed between the water samples, temperature and iron concentration were the characteristics that affected the bacterial community structure and composition in groundwater wells. Small increases in the concentration of iron in water modified the bacterial communities and promoted the growth of the iron-oxidizing bacteria Acidovorax. The abundance of the genera Flavobacterium and Duganella was correlated positively with temperature and the Acidobacteria Gp4 and Gp1, and the genus Acidovorax with iron concentrations in the well water. Large percentages of Flavobacterium and Pseudomonas bacteria were found, and this is of special concern as bacteria belonging to both genera are often biofilm developers, where pathogens survival increases.

Large Fractions of CO 2 -Fixing Microorganisms in Pristine Limestone Aquifers Appear To Be Involved in the Oxidation of Reduced Sulfur and Nitrogen Compounds

“…Members of the Betaproteobacteria and Cytophagales-Flavobacteria-Bacteroidetes group dominated the metabolically active communities in the upper aquifer. The dominance of Betaproteobacteria in groundwater agrees with data from previous reports (29,(55)(56)(57). Sequences related to facultative or obligate anaerobes, e.g., the genera Albidiferax, Limnohabitans, and Opitutus, together represented 26.2 to 30.5% of the sequences reads in the total active community in the upper aquifer, which reflects the oxygen-deficient conditions of this aquifer.…”

“…Recent studies addressing the microbial diversity in aquifers or drinking water wells by 16S rRNA gene-targeted pyrosequencing allowed comprehensive insight into the composition of microbial communities (14,(27)(28)(29). However, those studies were DNA based and did not allow characterization of active aquifer microbial community members, providing only limited insight into the physiologic strategies that are dominant under the given environmental conditions.…”

Pyrosequencing analysis of roof-harvested rainwater and river water used for domestic purposes in Luthengele village in the Eastern Cape Province of South Africa

“…At the genus taxonomic level the presence of large proportions of phylotypes belonging to the genera Acidovorax, Curvibacter and Gemmata, and the family Commamonadaceae in our study was similar to other findings in fresh water samples from around the world (Pinto et al 2012;Lautenschlager et al 2013;Navarro-noya et al 2013). …”

Bacteria in drinking water sources of a First Nation reserve in Canada

“…Several studies have used high-throughput sequencing technologies to investigate bacterial community diversity in water distribution systems locations or components (Kwon, 2011;Pinto et al, 2012;Douterelo et al, 2013;Navarro-Noya et al, 2013). In a recent study, we highlight the importance for such investigations in First Nations communities in Canada (Fernando et al, 2016).…”