A korarchaeal genome reveals insights into the evolution of the Archaea.

@article{citeulike:2873245, abstract = {The candidate division Korarchaeota comprises a group of uncultivated microorganisms that, by their small subunit rRNA phylogeny, may have diverged early from the major archaeal phyla Crenarchaeota and Euryarchaeota. Here, we report the initial characterization of a member of the Korarchaeota with the proposed name, "Candidatus Korarchaeum cryptofilum," which exhibits an ultrathin filamentous morphology. To investigate possible ancestral relationships between deep-branching Korarchaeota and other phyla, we used whole-genome shotgun sequencing to construct a complete composite korarchaeal genome from enriched cells. The genome was assembled into a single contig 1.59 Mb in length with a G + C content of 49\%. Of the 1,617 predicted protein-coding genes, 1,382 (85\%) could be assigned to a revised set of archaeal Clusters of Orthologous Groups (COGs). The predicted gene functions suggest that the organism relies on a simple mode of peptide fermentation for carbon and energy and lacks the ability to synthesize de novo purines, CoA, and several other cofactors. Phylogenetic analyses based on conserved single genes and concatenated protein sequences positioned the korarchaeote as a deep archaeal lineage with an apparent affinity to the Crenarchaeota. However, the predicted gene content revealed that several conserved cellular systems, such as cell division, DNA replication, and tRNA maturation, resemble the counterparts in the Euryarchaeota. In light of the known composition of archaeal genomes, the Korarchaeota might have retained a set of cellular features that represents the ancestral archaeal form.}, address = {Lehrstuhl f\"{u}r Mikrobiologie und Archaeenzentrum, Universit\"{a}t Regensburg, D-93053 Regensburg, Germany;}, author = {Elkins, James G G. and Podar, Mircea and Graham, David E E. and Makarova, Kira S S. and Wolf, Yuri and Randau, Lennart and Hedlund, Brian P P. and Brochier-Armanet, C\'{e}line and Kunin, Victor and Anderson, Iain and Lapidus, Alla and Goltsman, Eugene and Barry, Kerrie and Koonin, Eugene V V. and Hugenholtz, Phil and Kyrpides, Nikos and Wanner, Gerhard and Richardson, Paul and Keller, Martin and Stetter, Karl O O. }, citeulike-article-id = {2873245}, doi = {http://dx.doi.org/10.1073/pnas.0801980105}, issn = {1091-6490}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, keywords = {archaea, evolution, genome, koryarchaeota, koryarchaeum}, month = {June}, posted-at = {2008-06-08 08:54:30}, priority = {2}, title = {A korarchaeal genome reveals insights into the evolution of the Archaea.}, url = {http://dx.doi.org/10.1073/pnas.0801980105}, year = {2008} }

TY - JOUR ID - citeulike:2873245 L3 - citeulike-article-id:2873245 TI - A korarchaeal genome reveals insights into the evolution of the Archaea. JF - Proceedings of the National Academy of Sciences of the United States of America AD - Lehrstuhl für Mikrobiologie und Archaeenzentrum, Universität Regensburg, D-93053 Regensburg, Germany; SN - 1091-6490 N2 - The candidate division Korarchaeota comprises a group of uncultivated microorganisms that, by their small subunit rRNA phylogeny, may have diverged early from the major archaeal phyla Crenarchaeota and Euryarchaeota. Here, we report the initial characterization of a member of the Korarchaeota with the proposed name, "Candidatus Korarchaeum cryptofilum," which exhibits an ultrathin filamentous morphology. To investigate possible ancestral relationships between deep-branching Korarchaeota and other phyla, we used whole-genome shotgun sequencing to construct a complete composite korarchaeal genome from enriched cells. The genome was assembled into a single contig 1.59 Mb in length with a G + C content of 49%. Of the 1,617 predicted protein-coding genes, 1,382 (85%) could be assigned to a revised set of archaeal Clusters of Orthologous Groups (COGs). The predicted gene functions suggest that the organism relies on a simple mode of peptide fermentation for carbon and energy and lacks the ability to synthesize de novo purines, CoA, and several other cofactors. Phylogenetic analyses based on conserved single genes and concatenated protein sequences positioned the korarchaeote as a deep archaeal lineage with an apparent affinity to the Crenarchaeota. However, the predicted gene content revealed that several conserved cellular systems, such as cell division, DNA replication, and tRNA maturation, resemble the counterparts in the Euryarchaeota. In light of the known composition of archaeal genomes, the Korarchaeota might have retained a set of cellular features that represents the ancestral archaeal form. KW - archaea KW - evolution KW - genome KW - koryarchaeota KW - koryarchaeum AU - Elkins, James G AU - Podar, Mircea AU - Graham, David E AU - Makarova, Kira S AU - Wolf, Yuri AU - Randau, Lennart AU - Hedlund, Brian P AU - Brochier-Armanet, Céline AU - Kunin, Victor AU - Anderson, Iain AU - Lapidus, Alla AU - Goltsman, Eugene AU - Barry, Kerrie AU - Koonin, Eugene V AU - Hugenholtz, Phil AU - Kyrpides, Nikos AU - Wanner, Gerhard AU - Richardson, Paul AU - Keller, Martin AU - Stetter, Karl O PY - 2008/06/05/ UR - http://dx.doi.org/10.1073/pnas.0801980105 ER -