[en] The evolutionary history and geographical isolation of the Antarctic continent have produced a unique environment rich in endemic organisms. In many regions of Antarctica, cyanobacteria are the dominant phototrophs in both aquatic and terrestrial ecosystems. We have used microscopic and molecular approaches to examine the cyanobacterial diversity of biotopes at two inland continental Antarctic sites (80-82°S). These are amongst the most southerly locations where freshwater-related ecosystems are present. Results showed a low cyanobacterial diversity, with only 3-7 Operational Taxonomic Units (OTUs) per sample obtained by a combination of strain isolations, clone libraries and DGGE based on 16S rRNA genes. One OTU was potentially endemic to Antarctica and is present in several regions of the continent. Four OTUs were shared by the samples from Forlidas Pond and the surrounding terrestrial mats. Only one OTU, but no Internal Transcribed Spacer (ITS) sequences, was common to Forlidas Pond and Lundström Lake. The ITS sequences were shown to further discriminate different genotypes within the OTUs. ITS sequences from Antarctic locations appear more closely related to each other than to non-Antarctic sequences. Future research in inland continental Antarctica will shed more light on the geographical distribution and evolutionary isolation of cyanobacteria in these extreme habitats.
Research Center/Unit :
CIP - Centre d'Ingénierie des Protéines - ULiège
Disciplines :
Environmental sciences & ecology Microbiology
Author, co-author :
FERNANDEZ CARAZO, Rafael ; Centre Hospitalier Universitaire de Liège - CHU > Unilab > Laboratoire génétique moléculaire
Hodgson, Dominic
Convey, Pete
Wilmotte, Annick ; Université de Liège - ULiège > Département des sciences de la vie > Physiologie et génétique bactériennes
Language :
English
Title :
Low cyanobacterial diversity in biotopes of the Transantarctic Mountains and Shackleton Range (80-82°S), Antarctica.
Alternative titles :
Faible diversité cyanobactérienne dans les biotopes des Montagnes Transantarctiques et Shackleton Range (80-82°S), Antarctique