scholarly journals Hydrogenimonas thermophila gen. nov., sp. nov., a novel thermophilic, hydrogen-oxidizing chemolithoautotroph within the ε-Proteobacteria, isolated from a black smoker in a Central Indian Ridge hydrothermal field

2004 ◽  
Vol 54 (1) ◽  
pp. 25-32 ◽  
Author(s):  
Ken Takai ◽  
Kenneth H. Nealson ◽  
Koki Horikoshi
Keyword(s):  
Thermophilic Bacterium ◽  
Black Smoker ◽  
Central Indian Ridge ◽  
Rdna Sequences ◽  
16S Rdna Sequences ◽  
Group A ◽  
The Indian Ocean ◽  
Bacterium Strain ◽  
Indian Ridge

A novel thermophilic bacterium, strain EP1-55-1%T, was isolated from an in-situ colonization system deployed in a superheated, deep-sea, hydrothermal vent emission at the Kairei Field on the Central Indian Ridge in the Indian Ocean. The cells were highly motile rods, each possessing a single polar flagellum. Growth was observed between 35 and 65 °C (optimum temperature, 55 °C; 70 min doubling time) and between pH 4·9 and 7·2 (optimum, pH 5·9). The isolate was a microaerobic-to-anaerobic chemolithoautotroph capable of using molecular hydrogen as the sole energy source and carbon dioxide as the sole carbon source. Molecular oxygen, nitrate or elemental sulfur (S0) could serve as electron acceptors to support growth. The G+C content of the genomic DNA was 34·6 mol%. Phylogenetic analysis based on 16S rDNA sequences indicated that strain EP1-55-1%T represents the first strain for which taxonomic properties have been characterized within the previously uncultivated phylogroup classified as belonging to the uncultivated ε-Proteobacteria group A; the name Hydrogenimonas thermophila gen. nov., sp. nov. is proposed, with strain EP1-55-1%T (=JCM 11971T=ATCC BAA-737T) as the type strain.

Segmentation of the Central Indian Ridge between 12°12′ S and the Indian Ocean Triple Junction

1993 ◽  
Vol 15 (4) ◽  
pp. 265-282 ◽  
Author(s):  
Lindsay M. Parson ◽  
Philippe Patriat ◽  
Roger C. Searle ◽  
Anne R. Briais
Keyword(s):  
Indian Ocean ◽  
Triple Junction ◽  
Central Indian Ridge ◽  
The Indian Ocean ◽  
Indian Ridge

scholarly journals Coexistence of Wolbachia with Buchnera aphidicola and a Secondary Symbiont in the Aphid Cinara cedri

2004 ◽  
Vol 186 (19) ◽  
pp. 6626-6633 ◽  
Author(s):  
Laura Gómez-Valero ◽  
Mario Soriano-Navarro ◽  
Vicente Pérez-Brocal ◽  
Abdelaziz Heddi ◽  
Andrés Moya ◽  
...  
Keyword(s):  
Bacterial Genome ◽  
Pcr Amplification ◽  
Bacterial Cells ◽  
Buchnera Aphidicola ◽  
Rdna Genes ◽  
16S Ribosomal Dna ◽  
Secondary Symbiont ◽  
Rdna Sequences ◽  
16S Rdna Sequences

ABSTRACT Intracellular symbiosis is very common in the insect world. For the aphid Cinara cedri, we have identified by electron microscopy three symbiotic bacteria that can be characterized by their different sizes, morphologies, and electrodensities. PCR amplification and sequencing of the 16S ribosomal DNA (rDNA) genes showed that, in addition to harboring Buchnera aphidicola, the primary endosymbiont of aphids, C. cedri harbors a secondary symbiont (S symbiont) that was previously found to be associated with aphids (PASS, or R type) and an α-proteobacterium that belongs to the Wolbachia genus. Using in situ hybridization with specific bacterial probes designed for symbiont 16S rDNA sequences, we have shown that Wolbachia was represented by only a few minute bacteria surrounding the S symbionts. Moreover, the observed B. aphidicola and the S symbionts had similar sizes and were housed in separate specific bacterial cells, the bacteriocytes. Interestingly, in contrast to the case for all aphids examined thus far, the S symbionts were shown to occupy a similarly sized or even larger bacteriocyte space than B. aphidicola. These findings, along with the facts that C. cedri harbors the B. aphidicola strain with the smallest bacterial genome and that the S symbionts infect all Cinara spp. analyzed so far, suggest the possibility of bacterial replacement in these species.

Thermodesulfatator indicus gen. nov., sp. nov., a novel thermophilic chemolithoautotrophic sulfate-reducing bacterium isolated from the Central Indian Ridge

2004 ◽  
Vol 54 (1) ◽  
pp. 227-233 ◽  
Author(s):  
H. Moussard ◽  
S. L'Haridon ◽  
B. J. Tindall ◽  
A. Banta ◽  
P. Schumann ◽  
...  
Keyword(s):  
Type Species ◽  
Phylogenetic Analyses ◽  
Rrna Gene ◽  
Central Indian Ridge ◽  
Sulfate Reducing ◽  
The Family ◽  
Fermentative Growth ◽  
Bacterium Strain ◽  
Indian Ridge ◽  
Ph Range

A thermophilic, marine, anaerobic, chemolithoautotrophic, sulfate-reducing bacterium, strain CIR29812T, was isolated from a deep-sea hydrothermal vent site at the Kairei vent field on the Central Indian Ridge. Cells were Gram-negative motile rods that did not form spores. The temperature range for growth was 55–80 °C, with an optimum at 70 °C. The NaCl concentration range for growth was 10–35 g l−1, with an optimum at 25 g l−1. The pH range for growth was 6–6·7, with an optimum at approximately pH 6·25. H2 and CO2 were the only electron donor and carbon source found to support growth of the strain. However, several organic compounds were stimulatory for growth. Sulfate was used as electron acceptor, whereas elemental sulfur, thiosulfate, sulfite, cystine, nitrate and fumarate were not. No fermentative growth was observed with malate, pyruvate or lactate. The phenotypic characteristics of strain CIR29812T were similar to those of Thermodesulfobacterium hydrogeniphilum, a recently described thermophilic, chemolithoautotrophic sulfate-reducer. However, phylogenetic analyses of the 16S rRNA gene sequences showed that the new isolate was distantly related to members of the family Thermodesulfobacteriaceae (similarity values of less than 90 %). The chemotaxonomic data (fatty acids and polar lipids composition) also indicated that strain CIR29812T could be distinguished from Thermodesulfobacterium commune, the type species of the type genus of the family Thermodesulfobacteriaceae. Finally, the G+C content of the genomic DNA of strain CIR29812T (46·0 mol%) was not in the range of values obtained for members of this family. On the basis of phenotypic, chemotaxonomic and genomic features, it is proposed that strain CIR29812T represents a novel species of a new genus, Thermodesulfatator, of which Thermodesulfatator indicus is the type species. The type strain is CIR29812T (=DSM 15286T=JCM 11887T).

scholarly journals Niche-Partitioning of ProchlorococcusPopulations in a Stratified Water Column in the Eastern North Atlantic Ocean

1999 ◽  
Vol 65 (6) ◽  
pp. 2585-2591 ◽  
Author(s):  
Nyree J. West ◽  
David J. Scanlan
Keyword(s):  
Water Column ◽  
16S Rdna ◽  
North Atlantic ◽  
North Atlantic Ocean ◽  
Niche Partitioning ◽  
Rdna Sequences ◽  
16S Rdna Sequences ◽  
Eastern North Atlantic ◽  
Eastern North Atlantic Ocean

ABSTRACT The in situ community structure of Prochlorococcuspopulations in the eastern North Atlantic Ocean was examined by analysis of Prochlorococcus 16S rDNA sequences with three independent approaches: cloning and sequencing, hybridization to specific oligonucleotide probes, and denaturing gradient gel electrophoresis (DGGE). The hybridization of high-light (HL) and low-light (LL) Prochlorococcus genotype-specific probes to two depth profiles of PCR-amplified 16S rDNA sequences revealed that in these two stratified water columns, an obvious niche-partitioning ofProchlorococcus genotypes occurred. In each water column a shift from the HL to the LL genotype was observed, a transition correlating with the depth of the surface mixed layer (SML). Only the HL genotype was found in the SML in each water column, whereas the LL genotype was distributed below the SML. The range of in situ irradiance to which each genotype was subjected within these distinct niches was consistent with growth irradiance studies of cultured HL- and LL-adapted Prochlorococcus strains. DGGE analysis and the sequencing of Prochlorococcus 16S rDNA clones were in full agreement with the genotype-specific oligonucleotide probe hybridization data. These observations of a partitioning ofProchlorococcus genotypes in a stratified water column provide a genetic basis for the dim and brightProchlorococcus populations observed in flow cytometric signatures in several oceanic provinces.

scholarly journals Citromicrobium bathyomarinum, a Novel Aerobic Bacterium Isolated from Deep-Sea Hydrothermal Vent Plume Waters That Contains Photosynthetic Pigment-Protein Complexes

1999 ◽  
Vol 181 (15) ◽  
pp. 4517-4525 ◽  
Author(s):  
Vladimir V. Yurkov ◽  
Steven Krieger ◽  
Erko Stackebrandt ◽  
J. Thomas Beatty
Keyword(s):  
Deep Sea ◽  
Hydrothermal Vents ◽  
Protein Complexes ◽  
Photosynthetic Pigment ◽  
Aerobic Bacterium ◽  
Black Smoker ◽  
Rdna Sequences ◽  
16S Rdna Sequences ◽  
Juan De Fuca ◽  
Pigment Protein Complexes

ABSTRACT We have taxonomically and phylogenetically characterized a new aerobic bacterial strain (JF-1) that contains photosynthetic pigment-protein complexes and which was recently isolated from black smoker plume waters of the Juan de Fuca Ridge. Strain JF-1 is a gram-negative, yellow-pigmented, motile bacterium that is salt-, pH-, and thermotolerant. These properties are consistent with an oligotrophic adaptation to varied environmental conditions thought to exist around deep-sea hydrothermal vents. The analysis of 16S rDNA sequences revealed that strain JF-1 forms a separate phylogenetic branch between the genus Erythromonas and theErythromicrobium-Porphyrobacter-Erythrobacter cluster within the α subclass of the Proteobacteria. The taxonomic name Citromicrobium bathyomarinum (gen. nov., sp. nov.) is proposed for strain JF-1.

scholarly journals Methanotorris formicicus sp. nov., a novel extremely thermophilic, methane-producing archaeon isolated from a black smoker chimney in the Central Indian Ridge

2004 ◽  
Vol 54 (4) ◽  
pp. 1095-1100 ◽  
Author(s):  
Ken Takai ◽  
Ken H. Nealson ◽  
Koki Horikoshi
Keyword(s):  
Dna Hybridization ◽  
Alternative Energy ◽  
Carbon Sources ◽  
Rrna Gene ◽  
Strictly Anaerobic ◽  
Black Smoker ◽  
Central Indian Ridge ◽  
Physiological Properties ◽  
Indian Ridge ◽  
C 30

A novel extremely thermophilic, methane-producing archaeon was isolated from a black smoker chimney at the Kairei field in the Central Indian Ridge. Cells of this isolate were irregular cocci with several flagella; motility was not observed. Growth was observed between 55 and 83 °C (optimum of 75 °C; 30 min doubling time) and between pH 6·0 and 8·5 (optimum of pH 6·7). The isolate was a strictly anaerobic, methanogenic autotroph capable of using hydrogen and carbon dioxide as sole energy and carbon sources. Formate was utilized as an alternative energy source. The G+C content of the genomic DNA was 33·3 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the isolate was most closely related to Methanotorris igneus strain Kol 5T. The isolate, however, could be genetically differentiated from this species by DNA–DNA hybridization analysis and on the basis of its physiological properties. The name Methanotorris formicicus sp. nov. is proposed for this isolate; the type strain is Mc-S-70T (=JCM 11930T=ATCC BAA-687T).

Sign in / Sign up

Export Citation Format

Share Document