Marine lipids
Exceptional lipids and fatty acids
in the marine pteropod Clione limacina
Gerhard Kattner (1) , Martin Graeve (1) , Wilhelm Hagen (2)
(1) Alfred Wegener Institute für Polar und Meeresforschung, PO Box 120161,
27515 Bremerhaven, Germany,
(2) Universität Kiel, Institut für Polarökologie, Wischhofstraβe 1-3, Gebäude 12,
24148 Kiel, Germany
The outstanding features of Clione limacina from the polar oceans are
the extraordinary lipid and fatty acid compositions. Up to 40.6% of
the total lipids consist of 1-O-alkyldiacylglycerol ethers (DAGE), a very
unusual depot lipid in the marine zooplankton. In addition, the various
lipid classes of C. limacina exhibit unique fatty acid compositions, due
to high percentages of odd-chain length components, up to one third
of total fatty acids. The dominant odd-chain fatty acid is 17:1 (n-8)
reaching 18% , followed by 15:0 and 17:0, with 17:1 (n-8) enriched in
the diacylglycerol ethers. In Limacina helicina, the only prey of C. limacina, neither diacylglycerol ethers nor odd-chain fatty acids could be cletected, indicating that these atypical lipids are not ingested with the prey.
De novo biosynthesis is therefore suggested. Propionate, the precursor
of the odd-chain fatty acids, may originate from dimethyl-|5-propiothetin (DMPT), which has been described to be accumulated by L. helicina via phytoplankton uptake. These odd-chain fatty acids may serve
as chemical defense agents, as indicated by their antifungal effect, a
possible advantage in these shell-less pteropods, together with the
production of terpenoid antifeedants.
106
Exceptional lipids and fatty acids
in the marine pteropod Clione limacina
Gerhard Kattner (1) , Martin Graeve (1) , Wilhelm Hagen (2)
(1) Alfred Wegener Institute für Polar und Meeresforschung, PO Box 120161,
27515 Bremerhaven, Germany,
(2) Universität Kiel, Institut für Polarökologie, Wischhofstraβe 1-3, Gebäude 12,
24148 Kiel, Germany
The outstanding features of Clione limacina from the polar oceans are
the extraordinary lipid and fatty acid compositions. Up to 40.6% of
the total lipids consist of 1-O-alkyldiacylglycerol ethers (DAGE), a very
unusual depot lipid in the marine zooplankton. In addition, the various
lipid classes of C. limacina exhibit unique fatty acid compositions, due
to high percentages of odd-chain length components, up to one third
of total fatty acids. The dominant odd-chain fatty acid is 17:1 (n-8)
reaching 18% , followed by 15:0 and 17:0, with 17:1 (n-8) enriched in
the diacylglycerol ethers. In Limacina helicina, the only prey of C. limacina, neither diacylglycerol ethers nor odd-chain fatty acids could be cletected, indicating that these atypical lipids are not ingested with the prey.
De novo biosynthesis is therefore suggested. Propionate, the precursor
of the odd-chain fatty acids, may originate from dimethyl-|5-propiothetin (DMPT), which has been described to be accumulated by L. helicina via phytoplankton uptake. These odd-chain fatty acids may serve
as chemical defense agents, as indicated by their antifungal effect, a
possible advantage in these shell-less pteropods, together with the
production of terpenoid antifeedants.
106