Seasonal dynamics of freshwater pathogens as measured by microarray at Lake Sapanca, a drinking water source in the north-eastern part of Turkey

Abstract

Monitoring drinking water quality is an important public health issue. Two objectives from the 4 years, six nations, EU Project μAqua were to develop hierarchically specific probes to detect and quantify pathogens in drinking water using a PCR-free microarray platform and to design a standardised water sampling program from different sources in Europe to obtain sufficient material for downstream analysis. Our phylochip contains barcodes (probes) that specifically identify freshwater pathogens that are human health risks in a taxonomic hierarchical fashion such that if species is present, the entire taxonomic hierarchy (genus, family, order, phylum, kingdom) leading to it must also be present, which avoids false positives. Molecular tools are more rapid, accurate and reliable than traditional methods, which means faster mitigation strategies with less harm to humans and the community. We present microarray results for the presence of freshwater pathogens from a Turkish lake used drinking water and inferred cyanobacterial cell equivalents from samples concentrated from 40 into 1 L in 45 min using hollow fibre filters. In two companion studies from the same samples, cyanobacterial toxins were analysed using chemical methods and those dates with highest toxin values also had highest cell equivalents as inferred from this microarray study.

The microbiome of modern microbialites in Bacalar Lagoon, Mexico

“…In addition, the sites with the lowest diversity that are located at the South-Center region of the lagoon, are the same sites that have been historically used for tourism. These results postulate that the changes in the microbiome of microbialites along Bacalar Lagoon are probably associated to a greater extent, with poor water quality due to high concentrations of ammonium and NOx [80,97]. (Table 1).…”

Application of the μAqua microarray for pathogenic organisms across a marine/freshwater interface

“…In the two sites where lakes were sampled (Turkey and the Netherlands), there is a clear development of cyanobacterial blooms, as would be expected from a water basin. Planktothrix was the dominant bloom former and displayed a clear seasonal pattern in the Turkish lakes being absent in the winter months (Akcaalan et al, 2017). Microcystis signals were also strong but colonies were never encountered and it was presumed that unicells were present as was documented in Medlin et al (2015) and Barra Caracciolo et al (2019) using the microarray validated by FISH and CARDFISH probes for Microcystis.…”

“…Within the μAqua project, the microarray was tested in 6 countries and cyanobacterial results were addressed in two sites above and below Rome in the Tiber River (Marcheggiani et al, 2015), 14 north German coastal fresh and brackish water sites (Baudart et al, 2016), six lakes in the Netherlands (Van Der Waal et al, 2017), one lake from Turkey (Akcaalan et al, 2017), several rivers and lakes in Ireland and one lake in Bulgaria (data never published). In the two sites where lakes were sampled (Turkey and the Netherlands), there is a clear development of cyanobacterial blooms, as would be expected from a water basin.…”

“…The microarray from the μAQUA project and the subsequent MicroCokit project that used the μAQUA phylochip was field tested in 6 countries. Results for four of the monitoring sites have been published: the Tiber River in Italy, (Marcheggiani et al, 2015;Medlin et al, 2017), the north German coastal fresh and brackish water sites (Baudart et al, 2016), six lakes in the Netherlands (Van Der Waal et al, 2017), one lake in Turkey (Akcaalan et al, 2017) and in this paper we present results for three sites in along the Mediterranean coast of south-east France ranging from fresh to brackish to full strength seawater, thus testing the distribution of these pathogens and the applicability of the probes across the marine/freshwater boundary. The results for the cyanobacteria and Protozoa are reported here, whereas the bacterial component will be reported elsewhere (Baudart and Guillebault unpublished).…”

Bacterial Community Composition of Sapanca Lake During a Cyanobacterial Bloom

“…It is a source for drinking water for the cities of Sakarya and Kocaeli, as well as for industrial usage (Akçaalan et al, 2014;Leroy & Albay, 2010), and has been monitored according to the presence of cyanobacteria and cyanotoxin for years to indicate the ecological status of the lake, and it has now a well-established cyanobacteria diversity (Akçaalan et al, 2007;Akçaalan et al, 2014). Moreover, there are some studies in the literature on Lake Sapanca which evaluated the total bacterial counts, pathogenic bacteria and petroleum-resistant bacteria presence by a culture dependent technique (Altuğ et al 2006;Çiftçi Türetken et al, 2018), and seasonal dynamics of pathogens by the microarray method (Akçaalan et al, 2018). So far, there have been no attempts to examine the total bacterial community structure in Lake Sapanca, and it has remained unclear.…”