|Picoplankton diversity in the Arctic Ocean and surrounding seas|
|Lovejoy, C.; Galand, P.E.; Kirchmann, D.L. (2011). Picoplankton diversity in the Arctic Ocean and surrounding seas. Mar. Biodiv. Spec. Issue 41(1): 5-12|
|In: Marine Biodiversity. Springer: Berlin. ISSN 1867-1616, more|
Archaea; Bacteria; Biodiversity; Genes; Sequencing; Marine
Microbes, which are organisms that are visible only with a microscope, drive global biogeochemical cycling and CO2-fixing forms are the base of the marine arctic food web. Two of the three domains of life, Bacteria and Archaea, are exclusively microbial, and microbes account for the majority of diversity within the third domain, Eucarya. Although morphological diversity among the smallest microbes is limited, phylogenetic diversity among microbes is vast. With each of several major technological advances, estimates of global microbial diversity increase by orders of magnitude. The Arctic is no exception, with most major groups of marine microbes having been found in arctic marine waters using molecular biological techniques. Here we provide a brief overview of microbial diversity revealed by environmental surveys of the small subunit rRNA gene (SS rRNA), which is the most widely used marker for identifying microbes. Similar to larger phytoplankton identified morphologically, small heterotrophic prokaryotes and photosynthetic eukaryotes in the Arctic are a mixture of uniquely arctic taxa and more cosmopolitan species. Among Bacteria, Proteobacteria are predominant in surface and deep waters as with other oceans. However, the recent massively parallel sequencing of the SS rRNA gene has revealed that at finer taxonomic scales arctic bacterial and archaeal communities also differ from their temperate counterparts, suggesting endemicity as well.