A new fluorescent oligonucleotide probe for in situ detection of s-triazine-degrading Rhodococcus wratislaviensis in contaminated groundwater and soil samples

The role of a groundwater bacterial community in the degradation of  the herbicide terbuthylazine

“…Bacterial degradation of s‐ triazines in groundwater has not been observed by other authors (Johnson et al , 2000; Pearson et al , 2006); however, we recently isolated a bacterial strain capable of using s ‐triazines as its sole carbon source in a pure liquid culture (Grenni et al , 2009b). To the best of our knowledge, the results of this study are the first to show that terbuthylazine (at 100 μg L −1 ) can be effectively biodegraded by the autochthonous bacterial community in groundwater microcosms.…”

“…In fact, the recalcitrant behaviour of the herbicide in groundwater could be a result of concentrations that are too low to induce bacterial degradation (Tappe et al , 2002). Biodegradation and mineralization of s ‐triazines have been shown to be carried out by bacterial consortia and by strains isolated from contaminated sites (Aislabie et al , 2005; Grenni et al , 2009b). Most commonly, the bacterial metabolism of s ‐triazines has been reported to occur via two different upper pathways.…”

“…Natural attenuation has been found in contaminated groundwater in situ (Tuxen et al, 2002;Williams et al, 2003) and in laboratory experiments using indigenous bacteria from contaminated sites (Mirigain et al, 1995;Franzmann et al, 2000;Johnson et al, 2000;Pucarevic et al, 2002;Harrison et al, 2003). To date, however, there have been few studies on natural attenuation in s-triazine-contaminated groundwater (Grenni et al, 2009b). The natural attenuation of other herbicides has only been found when the concentrations exceed 40 mg L À1 and when it is associated with acclimated bacterial communities displaying positive degradation of the compound (Johnson et al, 2000;Broholm et al, 2001;Tuxen et al, 2002).…”

Herbicide Contamination of Freshwater Ecosystems: Impact on Microbial Communities

“…This method was used, for example, by Pesce et al (2006), in a study of the effect of the phenylurea herbicide diuron on river microbial communities. However, this method can also be used for the in-situ detection of bacterial strains that are able to degrade herbicides, as for example by Grenni et al (2009). The DNA reassociation kinetics method has been also used to compare the genetic diversity of bacterial communities in more or less polluted soils (Gans et al, 2005), but not so far applied to freshwater ecosystems.…”

Identification of Microorganisms in Hydrocarbon-Contaminated Aquifer Samples by Fluorescence In Situ Hybridization (CARD-FISH)

“…One of the techniques thus affected is fluorescence in situ hybridization (FISH) of rRNA -at large, a widely used cultivation-independent method to investigate population dynamics and interspecies relationships at the single-cell level [19][20][21]. This fact is also reflected in the very low number of published studies using FISH in contaminated aquifer sediments (six in total: [22][23][24][25][26][27]). …”