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<front>
<journal-meta>
<journal-id journal-id-type="publisher">BG</journal-id>
<journal-title-group>
<journal-title>Biogeosciences</journal-title>
<abbrev-journal-title abbrev-type="publisher">BG</abbrev-journal-title>
<abbrev-journal-title abbrev-type="nlm-ta">Biogeosciences</abbrev-journal-title>
</journal-title-group>
<issn pub-type="epub">1726-4189</issn>
<publisher><publisher-name>Copernicus Publications</publisher-name>
<publisher-loc>Göttingen, Germany</publisher-loc>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.5194/bg-8-2547-2011</article-id>
<title-group>
<article-title>A laboratory experiment of intact polar lipid degradation in sandy sediments</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Logemann</surname>
<given-names>J.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Graue</surname>
<given-names>J.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Köster</surname>
<given-names>J.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Engelen</surname>
<given-names>B.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Rullkötter</surname>
<given-names>J.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Cypionka</surname>
<given-names>H.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Institute for Chemistry and Biology of the Marine Environment (ICBM), Carl von Ossietzky University of Oldenburg, P.O. Box 2503, 26111 Oldenburg, Germany</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>These authors contributed equally to this work.</addr-line>
</aff>
<pub-date pub-type="epub">
<day>13</day>
<month>09</month>
<year>2011</year>
</pub-date>
<volume>8</volume>
<issue>9</issue>
<fpage>2547</fpage>
<lpage>2560</lpage>
<permissions>
<copyright-statement>Copyright: &#x000a9; 2011 J. Logemann et al.</copyright-statement>
<copyright-year>2011</copyright-year>
<license license-type="open-access">
<license-p>This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit <ext-link ext-link-type="uri"  xlink:href="https://creativecommons.org/licenses/by/3.0/">https://creativecommons.org/licenses/by/3.0/</ext-link></license-p>
</license>
</permissions>
<self-uri xlink:href="https://bg.copernicus.org/articles/8/2547/2011/bg-8-2547-2011.html">This article is available from https://bg.copernicus.org/articles/8/2547/2011/bg-8-2547-2011.html</self-uri>
<self-uri xlink:href="https://bg.copernicus.org/articles/8/2547/2011/bg-8-2547-2011.pdf">The full text article is available as a PDF file from https://bg.copernicus.org/articles/8/2547/2011/bg-8-2547-2011.pdf</self-uri>
<abstract>
<p>Intact polar lipids (IPLs) are considered biomarkers for living biomass.
Their degradation in marine sediments, however, is poorly understood and
complicates interpretation of their occurrence in geological samples. To
investigate the turnover of IPLs, a degradation experiment with anoxic sandy
sediments from the North Sea was conducted. Intact cells of two organisms
that do not naturally occur in North Sea sediments were chosen as IPL
sources: (i) &lt;i&gt;Saccharomyces cerevisiae&lt;/i&gt;, representative for ester-bound acyl lipids that also occur in
&lt;i&gt;Bacteria&lt;/i&gt;, and (ii) the archaeon &lt;i&gt;Haloferax volcanii&lt;/i&gt;, representative for ether-bound isoprenoid lipids.
Surprisingly, IPLs with phosphoester-bound head groups showed approximately
the same degradation rate as IPLs with glycosidic head groups. Furthermore,
the results indicate a relatively fast degradation of &lt;i&gt;S. cerevisiae&lt;/i&gt; IPLs with ester-bound
moieties (analogs of bacterial membrane lipids) and no significant
degradation of archaeal IPLs with ether-bound moieties. Pore water and 16S
rRNA-based DGGE analysis showed only a minor influence of the IPL source on
microbial metabolism and community profiles. Due to our results, the
IPL-based quantification of &lt;i&gt;Archaea&lt;/i&gt; and &lt;i&gt;Bacteria&lt;/i&gt; should be interpreted with caution.</p>
</abstract>
<counts><page-count count="14"/></counts>
</article-meta>
</front>
<body/>
<back>
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