<?xml version='1.0' encoding='utf-8'?>
<oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
  <dc:contributor>K. Przybyla-Kelly</dc:contributor>
  <dc:contributor>D.A. Shively</dc:contributor>
  <dc:contributor>R.L. Whitman</dc:contributor>
  <dc:creator>M.N. Byappanahalli</dc:creator>
  <dc:date>2008</dc:date>
  <dc:description>The enterococcal surface protein (&lt;i&gt;esp&lt;/i&gt;) gene found in &lt;i&gt;Enterococcus faecalis&lt;/i&gt; and &lt;i&gt;E. faecium&lt;/i&gt; has recently been explored as a marker of sewage pollution in recreational waters but its occurrence and distribution in environmental enterococci has not been well-documented. If the &lt;i&gt;esp&lt;/i&gt; gene is found in environmental samples, there are potential implications for microbial source tracking applications. In the current study, a total of 452 samples (lake water, 100; stream water, 129; nearshore sand, 96; and backshore sand, 71; &lt;i&gt;Cladophora&lt;/i&gt; sp. (Chlorophyta), 41; and periphyton (mostly &lt;i&gt;Bacillariophyceae&lt;/i&gt;), 15) collected from the coastal watersheds of southern Lake Michigan were selectively cultured for enterococci and then analyzed for the &lt;i&gt;esp&lt;/i&gt; gene by PCR, targeting &lt;i&gt;E. faecalis/ E. faecium&lt;/i&gt; (&lt;i&gt;esp&lt;/i&gt;&lt;sub&gt;fs/fm&lt;/sub&gt;) and &lt;i&gt;E. faecium&lt;/i&gt; (&lt;i&gt;esp&lt;/i&gt;&lt;sub&gt;fm&lt;/sub&gt;). Overall relative frequencies for &lt;i&gt;esp&lt;/i&gt;&lt;sub&gt;fs/fm&lt;/sub&gt; and &lt;i&gt;esp&lt;/i&gt;&lt;sub&gt;fm&lt;/sub&gt; were 27.4 and 5.1%. Respective percent frequency for the &lt;i&gt;esp&lt;/i&gt;&lt;sub&gt;fs/fm&lt;/sub&gt; and &lt;i&gt;esp&lt;/i&gt;&lt;sub&gt;fm&lt;/sub&gt; was 36 and 14% in lake water; 38.8 and 2.3% in stream water; 24 and 6.3% in nearshore sand; 0% in backshore sand; 24.4 and 0% in &lt;i&gt;Cladophora&lt;/i&gt; sp.; and 33.3 and 0% in periphyton. The overall occurrence of both &lt;i&gt;esp&lt;/i&gt;&lt;sub&gt;fs/fm&lt;/sub&gt; and &lt;i&gt;esp&lt;/i&gt;&lt;sub&gt;fm&lt;/sub&gt; was significantly related (&lt;i&gt;χ&lt;/i&gt;&lt;sup&gt;2&lt;/sup&gt; = 49, &lt;i&gt;P&lt;/i&gt; &lt; 0.0001). Post-rain incidence of &lt;i&gt;esp&lt;/i&gt;&lt;sub&gt;fs/fm&lt;/sub&gt; increased in lake and stream water and nearshore sand. Further, &lt;i&gt;E. coli&lt;/i&gt; and enterococci cell densities were significant predictors for &lt;i&gt;esp&lt;/i&gt;&lt;sub&gt;fs/fm&lt;/sub&gt; occurrence in post-rain lake water, but &lt;i&gt;esp&lt;/i&gt;&lt;sub&gt;fm&lt;/sub&gt; was not. F&lt;sup&gt;+&lt;/sup&gt; coliphage densities were not significant predictors for &lt;i&gt;esp&lt;/i&gt;&lt;sub&gt;fm&lt;/sub&gt; or &lt;i&gt;esp&lt;/i&gt;&lt;sub&gt;fs/fm&lt;/sub&gt; gene incidence. In summary, the differential occurrence of the &lt;i&gt;esp&lt;/i&gt; gene in the environment suggests that it is not limited to human fecal sources and thus may weaken its use as a reliable tool in discriminating contaminant sources (i.e., human vs nonhuman).</dc:description>
  <dc:format>application/pdf</dc:format>
  <dc:identifier>10.1021/es800481p</dc:identifier>
  <dc:language>en</dc:language>
  <dc:title>Environmental occurrence of the enterococcal surface protein (&lt;i&gt;esp&lt;/i&gt;) gene is an unreliable indicator of human fecal contamination</dc:title>
  <dc:type>article</dc:type>
</oai_dc:dc>