TY - JOUR
T1 - Opportunistic Cyanobacteria in benthic microbial mats of a tropical lagoon, Tikehau Atoll, Tuamotu Archipelago
T2 - Minor in natural populations, major in cultures
AU - Palińska, Katarzyna A.
AU - Abed, Raeid M.M.
AU - Wendt, Katja
AU - Charpy, Loic
AU - Łotocka, Maria
AU - Golubic, Stjepko
PY - 2012
Y1 - 2012
N2 - Studies in microbial ecology focus on identifying field dominant microbial populations using culture-independent tools, whereas minor populations are often ignored. We characterized the cyanobacterial populations from the Tikehau Atoll lagoon, Tuamotu Archipelago, which responded to standard culturing media. The cultivation approach recruited cryptic cyanobacterial taxa, which were not observed in the studied mats, as revealed by microscopic comparison. Twelve strains belonging to the unicellular genera (Aphanothece Nägeli, Chlorogloea Wille and Cyanocystis Borzi) and the filamentous cyanobacteria with narrow filaments (Leptolyngbya Anagnostidis et Komárek, Phormidium Küzing ex Gomont and Pseudanabaena Lauterborn) dominated the cultures. The genera Cyanocystis and Chlorogloea were genotypically characterized for the first time. Four strains assigned to Phormidium showed 100% identity using 16S rRNA sequences but additional gene analyses as well as phenotypic distinctions suggest finer differentiation within this group. Eight cyanobacterial strains out of twelve fixed dinitrogen with rates ranging from 3.3 up to 15.8 nmoles N2 μg-1 Chl-a h-1 and their nitrogen fixation ability was further confirmed by molecular detection of nifH gene. Nine strains possessed phycoerythrin, and two performed complementary chromatic adaptation. The present study documented the existence of an autochthonous subdominant cyanobacterial assemblage with variable physiological features that may enable them to replace dominant species in the microbial mats of Tikehau Atoll lagoon. These minor populations may be ecologically important, particularily in case of environmental disturbances.
AB - Studies in microbial ecology focus on identifying field dominant microbial populations using culture-independent tools, whereas minor populations are often ignored. We characterized the cyanobacterial populations from the Tikehau Atoll lagoon, Tuamotu Archipelago, which responded to standard culturing media. The cultivation approach recruited cryptic cyanobacterial taxa, which were not observed in the studied mats, as revealed by microscopic comparison. Twelve strains belonging to the unicellular genera (Aphanothece Nägeli, Chlorogloea Wille and Cyanocystis Borzi) and the filamentous cyanobacteria with narrow filaments (Leptolyngbya Anagnostidis et Komárek, Phormidium Küzing ex Gomont and Pseudanabaena Lauterborn) dominated the cultures. The genera Cyanocystis and Chlorogloea were genotypically characterized for the first time. Four strains assigned to Phormidium showed 100% identity using 16S rRNA sequences but additional gene analyses as well as phenotypic distinctions suggest finer differentiation within this group. Eight cyanobacterial strains out of twelve fixed dinitrogen with rates ranging from 3.3 up to 15.8 nmoles N2 μg-1 Chl-a h-1 and their nitrogen fixation ability was further confirmed by molecular detection of nifH gene. Nine strains possessed phycoerythrin, and two performed complementary chromatic adaptation. The present study documented the existence of an autochthonous subdominant cyanobacterial assemblage with variable physiological features that may enable them to replace dominant species in the microbial mats of Tikehau Atoll lagoon. These minor populations may be ecologically important, particularily in case of environmental disturbances.
KW - 16S rRNA
KW - Autochthonous
KW - Benthos
KW - Cyanobacteria
KW - NifH
KW - Polyphasic approach
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U2 - 10.5507/fot.2012.010
DO - 10.5507/fot.2012.010
M3 - Article
AN - SCOPUS:84856746107
SN - 1802-5439
VL - 12
SP - 127
EP - 140
JO - Fottea
JF - Fottea
IS - 1
ER -