Download 18S rRNA clone library of phytoplankton in the Columbia River

18S rRNA clone library of
phytoplankton in the
Columbia River and its
coastal zone
By Pete Kahn
Mentors: Lydie Herfort and
Peter Zuber
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http://www.mapwatch.com/news-blog/images/phytoplankton.jpg
Significance of phytoplankton
Major producers:
O2: 90%
CO2=>C3: 50%
 Base of aquatic food
chain

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Interactions with other Domains
Bacterioplankton
Colonization :
Competition
for NO32- and
NH3?
POC=>DOC
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http://www.fossilmuseum.net/Tree_of_Life/Domains_Archaea_Bacteria/Domains_of_life.jpg
Significance: Why is CMOP
interested in Phytoplankton?
Base of aquatic food chain
 Major producers: O2: 90%;
CO2=>C3: 50%
 Interaction with other two
Domains
-Crenarchaeota: “competition”
-Bacterioplankton: colonization
-POC=>DOC

Marine Phytoplankton bloom off
the coast of Argentina
http://www.mapwatch.com/news-blog/images/phytoplankton.jpg
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Traditional Methods
Flow cytometry
Microscopy
 Flow Cytometry
 Chlorophyll a
 Photosynthesis:
O2 production
C14 uptake

Microscopy:
Pediastrium
http://upload.wikimedia.org/wikipedia/commons/c/c7/Pi
coplancton_cytometrie.jpg
http://www.keweenawalgae.mtu.edu/ALGAL_IMAGES/
chlorophyceans/Pediastrium_n16_dollartow3_402_c.jpg
Filtering for
chlorophyll a
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Objectives




18S rRNA clone library for different seasons and
different locations: 0 PSU, 30 PSU for spring and
summer; compare to winter samples
Compare with Bacteria &
Archaea clone libraries from
Dan Murphy
Identify unexpected changes
Monitor health of ecosystem
Pediastrium
http://www.keweenawalgae.mtu.edu/ALGAL_IMAGES/chlorophyceans/Pedia
strium_n16_dollartow3_402_c.jpg
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Understand
Phytoplankton
community in
estuary
Methods Overview
Phylogenetic
analysis
Sequence
analysis w/
BLAST
Yan, Q. Y., Yu, Y. H. & Feng, W. S. (2006). Genetic fingerprinting of plankton community provides new insights into aquatic ecology. Progress in Natural Science
16, 893-898.
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Methods Overview
Water sample => Sterivex on site
Total nucleic acid extraction from sterivex in lab
Amplification through PCR
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Variations in nucleic acid in
environmental samples
Oct 2006
DNA
Feb 2007


Between seasons
Between locations
April Wecoma &
Forerunner: Freshwater
<< Surface Coastal
RNA
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