Prokaryotic diversity of arctic ice shelf microbial mats

• Main Authors: Eric M. Bottos, Warwick F. Vincent, Charles W. Greer, Lyle G. Whyte, Département De Biologie
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Arctic; Markham; Ward Hunt Ice Shelf; Ice Shelf; Ice Shelves; Markham Ice Shelf
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.517.4407; http://www.cen.ulaval.ca/warwickvincent/PDFfiles/222.pdf

The prokaryotic diversity and respiratory activity of microbial mat communities on the Markham Ice Shelf and Ward Hunt Ice Shelf in the Canadian high Arctic were analysed. All heterotrophic isolates and> 95% of bacterial 16S rRNA gene clone library sequences from both ice shelves grouped within the phyla Bacteroidetes, Proteobacteria and Actinobacteria. Clone library analyses showed that the bacterial communities were diverse and varied significantly between the two ice shelves, with the Markham library having a higher estimated diversity (Chao1 = 243; 105 operational taxonomic units observed in 189 clones) than the Ward Hunt library (Chao1 = 106; 52 opera-tional taxonomic units observed in 128 clones). Archaeal 16S rRNA gene clone libraries from both ice shelves were dominated by a single Euryarchaeota sequence, which appears to represent a novel phylotype. Analyses of community activity by radio-respiration assays detected metabolism in mat samples from both ice shelves at temperatures as low as-10°C. These findings provide the first insight into the prokaryotic biodiversity of Arctic ice shelf com-munities and underscore the importance of these cryo-ecosystems as a rich source of microbiota that are adapted to extreme cold.