TY - JOUR
T1 - Diversity and dynamics of Antarctic marine microbial eukaryotes under manipulated environmental UV radiation
AU - Piquet, Anouk M. -T.
AU - Bolhuis, Henk
AU - Davidson, Andrew T.
AU - Thomson, Paul G.
AU - Buma, Anita G. J.
PY - 2008/11
Y1 - 2008/11
N2 - In the light of the predicted global climate change, it is essential that the status and diversity of polar microbial communities is described and understood. In the present study, molecular tools were used to investigate the marine eukaryotic communities of Prydz Bay, Eastern Antarctica, from November 2002 to January 2003. Additionally, we conducted four series of minicosm experiments, where natural Prydz Bay communities were incubated under six different irradiation regimes, in order to investigate the effects of natural UV radiation on marine microbial eukaryotes. Denaturing gradient gel electrophoresis (DGGE) and 18S rRNA gene sequencing revealed a eukaryotic Shannon diversity index averaging 2.26 and 2.12, respectively. Phylogenetic analysis of 472 sequenced clones revealed 47 phylotypes, belonging to the Dinophyceae, Stramenopiles, Choanoflagellidae, Ciliophora, Cercozoa and Metazoa. Throughout the studied period, three communities were distinguished: a postwinter/early spring community comprising dinoflagellates, ciliates, cercozoans, stramenopiles, viridiplantae, haptophytes and metazoans; a dinoflagellate-dominated community; and a diatom-dominated community that developed after sea ice breakup. DGGE analysis showed that size fraction and time had a strong shaping effect on the community composition; however, a significant contribution of natural UV irradiance towards microeukaryotic community composition could not be detected. Overall, dinoflagellates dominated our samples and their diversity suggests that they fulfill an important role in Antarctic coastal marine ecosystems preceding ice breakup as well as between phytoplankton bloom events.
AB - In the light of the predicted global climate change, it is essential that the status and diversity of polar microbial communities is described and understood. In the present study, molecular tools were used to investigate the marine eukaryotic communities of Prydz Bay, Eastern Antarctica, from November 2002 to January 2003. Additionally, we conducted four series of minicosm experiments, where natural Prydz Bay communities were incubated under six different irradiation regimes, in order to investigate the effects of natural UV radiation on marine microbial eukaryotes. Denaturing gradient gel electrophoresis (DGGE) and 18S rRNA gene sequencing revealed a eukaryotic Shannon diversity index averaging 2.26 and 2.12, respectively. Phylogenetic analysis of 472 sequenced clones revealed 47 phylotypes, belonging to the Dinophyceae, Stramenopiles, Choanoflagellidae, Ciliophora, Cercozoa and Metazoa. Throughout the studied period, three communities were distinguished: a postwinter/early spring community comprising dinoflagellates, ciliates, cercozoans, stramenopiles, viridiplantae, haptophytes and metazoans; a dinoflagellate-dominated community; and a diatom-dominated community that developed after sea ice breakup. DGGE analysis showed that size fraction and time had a strong shaping effect on the community composition; however, a significant contribution of natural UV irradiance towards microeukaryotic community composition could not be detected. Overall, dinoflagellates dominated our samples and their diversity suggests that they fulfill an important role in Antarctic coastal marine ecosystems preceding ice breakup as well as between phytoplankton bloom events.
KW - Antarctic
KW - marine micro-eukaryotes
KW - 18S rRNA gene
KW - DGGE
KW - diversity
KW - UV radiation
KW - ULTRAVIOLET-B RADIATION
KW - EVOLUTIONARY GENETICS ANALYSIS
KW - GRADIENT GEL-ELECTROPHORESIS
KW - PHYTOPLANKTON STANDING CROP
KW - SOUTHERN-OCEAN
KW - ROSS SEA
KW - PRIMARY PRODUCTIVITY
KW - CERCOZOA PROTOZOA
KW - WEDDELL SEA
KW - FAST ICE
U2 - 10.1111/j.1574-6941.2008.00588.x
DO - 10.1111/j.1574-6941.2008.00588.x
M3 - Article
SN - 0168-6496
VL - 66
SP - 352
EP - 366
JO - FEMS Microbial Ecology
JF - FEMS Microbial Ecology
IS - 2
ER -