Limits...
Genome analysis of the anaerobic thermohalophilic bacterium Halothermothrix orenii.

Mavromatis K, Ivanova N, Anderson I, Lykidis A, Hooper SD, Sun H, Kunin V, Lapidus A, Hugenholtz P, Patel B, Kyrpides NC - PLoS ONE (2009)

Bottom Line: This is the first genome sequence of an organism belonging to the Haloanaerobiales.Protein sequence analyses and metabolic reconstruction reveal a unique combination of strategies for thermophilic and halophilic adaptation.H. orenii can serve as a model organism for the study of the evolution of the Gram negative phenotype as well as the adaptation under thermohalophilic conditions and the development of biotechnological applications under conditions that require high temperatures and high salt concentrations.

View Article: PubMed Central - PubMed

Affiliation: DOE- Joint Genome Institute, Walnut Creek, California, United States of America. KMavrommatis@lbl.gov

ABSTRACT
Halothermothirx orenii is a strictly anaerobic thermohalophilic bacterium isolated from sediment of a Tunisian salt lake. It belongs to the order Halanaerobiales in the phylum Firmicutes. The complete sequence revealed that the genome consists of one circular chromosome of 2578146 bps encoding 2451 predicted genes. This is the first genome sequence of an organism belonging to the Haloanaerobiales. Features of both Gram positive and Gram negative bacteria were identified with the presence of both a sporulating mechanism typical of Firmicutes and a characteristic Gram negative lipopolysaccharide being the most prominent. Protein sequence analyses and metabolic reconstruction reveal a unique combination of strategies for thermophilic and halophilic adaptation. H. orenii can serve as a model organism for the study of the evolution of the Gram negative phenotype as well as the adaptation under thermohalophilic conditions and the development of biotechnological applications under conditions that require high temperatures and high salt concentrations.

Show MeSH
H.orenii phylogeny.Maximum likelihood tree of 22 single copy genes from H.orenii and 49 reference genomes.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC2626281&req=5

pone-0004192-g002: H.orenii phylogeny.Maximum likelihood tree of 22 single copy genes from H.orenii and 49 reference genomes.

Mentions: H. orenii is currently classified as a member of the order Halanaerobiales in the class Clostridia of the Firmicutes (low G+C Gram positive) phylum on the basis of comparative 16S rRNA sequence analysis [3]. However, the Halanaerobiales is a basal Firmicutes lineage that has been proposed may represent an independent phylum [5]. This suggestion was based on inconsistent support of Firmicutes monophyly when all of its lineages are included in 16S rRNA gene trees either reflecting real polyphyly or the limit of resolution of the single gene (16S) phylogeny. To resolve this question we constructed a maximum likelihood tree of 22 concatenated conserved protein coding genes from H. orenii and 49 reference organisms with completed genome sequences. This analysis confirms that H. orenii is monophyletic with the other representatives of the Firmicutes (100% bootstrap support), but does not confirm a specific association with the class Clostridia (Fig. 2). Additional representatives of the Halanaerobiales will likely reveal if this order has a specific affiliation to the Clostridia.


Genome analysis of the anaerobic thermohalophilic bacterium Halothermothrix orenii.

Mavromatis K, Ivanova N, Anderson I, Lykidis A, Hooper SD, Sun H, Kunin V, Lapidus A, Hugenholtz P, Patel B, Kyrpides NC - PLoS ONE (2009)

H.orenii phylogeny.Maximum likelihood tree of 22 single copy genes from H.orenii and 49 reference genomes.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2626281&req=5

pone-0004192-g002: H.orenii phylogeny.Maximum likelihood tree of 22 single copy genes from H.orenii and 49 reference genomes.
Mentions: H. orenii is currently classified as a member of the order Halanaerobiales in the class Clostridia of the Firmicutes (low G+C Gram positive) phylum on the basis of comparative 16S rRNA sequence analysis [3]. However, the Halanaerobiales is a basal Firmicutes lineage that has been proposed may represent an independent phylum [5]. This suggestion was based on inconsistent support of Firmicutes monophyly when all of its lineages are included in 16S rRNA gene trees either reflecting real polyphyly or the limit of resolution of the single gene (16S) phylogeny. To resolve this question we constructed a maximum likelihood tree of 22 concatenated conserved protein coding genes from H. orenii and 49 reference organisms with completed genome sequences. This analysis confirms that H. orenii is monophyletic with the other representatives of the Firmicutes (100% bootstrap support), but does not confirm a specific association with the class Clostridia (Fig. 2). Additional representatives of the Halanaerobiales will likely reveal if this order has a specific affiliation to the Clostridia.

Bottom Line: This is the first genome sequence of an organism belonging to the Haloanaerobiales.Protein sequence analyses and metabolic reconstruction reveal a unique combination of strategies for thermophilic and halophilic adaptation.H. orenii can serve as a model organism for the study of the evolution of the Gram negative phenotype as well as the adaptation under thermohalophilic conditions and the development of biotechnological applications under conditions that require high temperatures and high salt concentrations.

View Article: PubMed Central - PubMed

Affiliation: DOE- Joint Genome Institute, Walnut Creek, California, United States of America. KMavrommatis@lbl.gov

ABSTRACT
Halothermothirx orenii is a strictly anaerobic thermohalophilic bacterium isolated from sediment of a Tunisian salt lake. It belongs to the order Halanaerobiales in the phylum Firmicutes. The complete sequence revealed that the genome consists of one circular chromosome of 2578146 bps encoding 2451 predicted genes. This is the first genome sequence of an organism belonging to the Haloanaerobiales. Features of both Gram positive and Gram negative bacteria were identified with the presence of both a sporulating mechanism typical of Firmicutes and a characteristic Gram negative lipopolysaccharide being the most prominent. Protein sequence analyses and metabolic reconstruction reveal a unique combination of strategies for thermophilic and halophilic adaptation. H. orenii can serve as a model organism for the study of the evolution of the Gram negative phenotype as well as the adaptation under thermohalophilic conditions and the development of biotechnological applications under conditions that require high temperatures and high salt concentrations.

Show MeSH