Genetic diversity of eukaryotic picoplankton in Astan (Roscoff) by SSU rRNA gene cloning and sequencing

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Genetic diversity of eukaryotic picoplankton in
Astan (Roscoff) by SSU rRNA gene cloning and
sequencing

• Khadidja Romari, Fabrice Not Daniel Vaulot
• Station biologique de Roscoff

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Environmental sample (pre-filtration and
filtration)
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Librarie clones screening
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(No Transcript)
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Neighbor-joining dendrogram of the picoeukaryote
groups found in the four libraries
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Distribution of the picoeukaryote groups during
the four seasons
Ex RA000412 station of the cruise, year,
month, day
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April 2000
December 2000
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Neighbor-joining dendrogram of the picoeukaryote
groups found in the four libraries clones
?
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Part of tree extracted from ARB indicating a
position of the He000427.214 group
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SSU rDNA phylogenetic relationshipps (Parcimony
ML tree) between 13 clones of He000427.214 group
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Neighbor-joining dendrogram of the picoeukaryote
groups found in the four libraries clones
?
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Part of tree extracted from ARB indicating a
position of the LKM 74 group
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SSU rDNA phylogenetic relationshipps (Parcimony
ML tree) between 13 clones of LKM 74 group
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Neighbor-joining dendrogram of the picoeukaryote
groups found in the four libraries clones
?
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Part of tree extracted from ARB, indicating a
position of the clone RA000609.30
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Conclusion

• The phylogenetic diversity in each library was
  rather large

• Low redundancy

• Of a total of 224 eukaryal clones, 85 affiliated
  with algal class and 79
• clones are affiliated with clearly heterotrophic
  group

• The spring clone library is largely dominated by
  the phototrophic
• group Prasinophyte and chryptophyceae

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Conclusion

• Some sequences are found identical in both
  Helgoland and Roscoff
• clone libraries

• Two novel group appeared
• He000427.214 (13 clones)
• LKM 74 (9 clones)