Using Bacteroidales genetic markers to assess fecal pollution sources in coastal waters

Abstract

Fecal pollution is the leading cause of beach closures in coastal regions of the United States. Identification of fecal pollution sources is necessary to implement effective pollution control strategies. This study sought to determine whether humans and cattle contributed to the fecal contamination at a public beach in Alabama, USA. High levels of enterococci were observed after significant rainfall events, of which 36 samples (35.6%) exceeded USEPA's statistical threshold value of 130 CFU/100 mL. Quantitative polymerase chain reaction (qPCR) assays were used to determine general (AllBac), human-(HF183), and cattle-associated (CowM3) Bacteroidales. There was a positive correlation between the levels of enterococci and AllBac markers. Our results suggest that fecal contamination from cattle was minimal and contamination from humans appeared to originate from diffuse sources. Stormwater runoff has the potential to supply considerable loads of fecal bacteria to coastal waters. Further research is needed to determine the contribution of other animals to fecal contamination in the region. 84 Water and Environment Journal 32 (2018) 84-93 V C 2017 CIWEM. Water and Environment Journal. Print ISSN 1747-6585 J. Xue et al. Fecal pollution sources in coastal waters Fecal pollution sources in coastal waters J. Xue et al.

Evaluation of Host Associated Genetic Markers for Rapid PCR Based Identification of Fecal Contamination Sources in Water

“…Open Access L independent Microbial Source Tracking (MST) methods based on the polymerase chain reaction (PCR) technique that target host specific molecular markers. Combining MST methods with end point PCR and qPCR should provide results that reflect the most recent fecal pollution and identify the sources, thus enabling us to develop better pollution control strategies [7][8][9].…”

Determination of adsorption and desorption of DNA molecules on freshwater and marine sediments

“…; Xue et al . , ). However, PCR is capable of detecting DNA from culturable cells, nonviable intact cells, viable but nonculturable (VBNC) cells, and extracellular free DNA (Rogers et al .…”

“…Genetic markers that target members of the order Bacteroidales are being increasingly used as alternative faecal indicator bacteria (FIB) due to their host specificity, sensitivity and high abundance (Wexler 2007). Compared with cultivation-based methods, the quantitative polymerase chain reaction (qPCR) assays not only detect but also quantify faecal pollution sources in surface waters (Scott et al 2002;Xue et al 2017aXue et al , 2017b. However, PCR is capable of detecting DNA from culturable cells, nonviable intact cells, viable but nonculturable (VBNC) cells, and extracellular free DNA (Rogers et al 2011).…”