A new phylum of Archaea represented by a nanosized hyperthermophilic symbiont

Huber, Harald; Hohn, Michael J.; Rachel, Reinhard; Fuchs, Tanja; Wimmer, Verena C.; Stetter, Karl O.

doi:10.1038/417063a

Cited by 730 publications

(581 citation statements)

References 23 publications

Supporting

Mentioning

555

Contrasting

Unclassified

Order By: Relevance

“…Only a few archaeal groups are diderm (Klingl 2014). The only diderm archaea that has been studied in detail is Ignicoccus hospitalis (Huber et al 2002;Küper et al 2010). The volume of Ignicoccus inter-membrane space can be large (20-1000 nm) and contains numerous vesicles that bud from the inner membrane and fuse with the OM (Näther & Rachel 2004).…”

Section: Emvs In Archaeamentioning

confidence: 99%

See 1 more Smart Citation

Origin of life: LUCA and extracellular membrane vesicles (EMVs)

Gill

Forterre

2015

International Journal of Astrobiology

View full text Add to dashboard Cite

Cells from the three domains of life produce extracellular membrane vesicles (EMVs), suggesting that EMV production is an important aspect of cellular physiology. EMVs have been implicated in many aspects of cellular life in all domains, including stress response, toxicity against competing strains, pathogenicity, detoxification and resistance against viral attack. These EMVs represent an important mode of inter-cellular communication by serving as vehicles for transfer of DNA, RNA, proteins and lipids between cells. Here, we review recent progress in the understanding of EMV biology and their various roles. We focus on the role of membrane vesicles in early cellular evolution and how they would have helped shape the nature of the last universal common ancestor. A membrane-protected microenvironment would have been a key to the survival of spontaneous molecular systems and efficient metabolic reactions. Interestingly, the morphology of EMVs is strongly reminiscent of the morphology of some virions. It is thus tempting to make a link between the origin of the first protocell via the formation of vesicles and the origin of viruses.

show abstract

Section: Emvs In Archaeamentioning

confidence: 99%

“…Ignicoccus hospitalis usually harbours several cells of the tiny archaeon Nanoarchaeum equitans on its surface (Huber et al 2002). N. equitans has the smallest known genome size for an archaeon (0.49 Mb) and cannot synthesize many essential components, including lipids (Waters et al 2003).…”

Section: Emvs In Archaeamentioning

confidence: 99%

Origin of life: LUCA and extracellular membrane vesicles (EMVs)

Gill

Forterre

2015

International Journal of Astrobiology

View full text Add to dashboard Cite

show abstract

“…It was suggested that this organization may correspond to the ancestral form of reverse gyrase, according to the early emergence of N. equitans at the base of the archaeal domain in both SSU rRNA (Huber et al 2002) and concatenated ribosomal protein trees (Waters et al 2003). However, this archaeon emerged as a sister group of Thermococcales in the reverse gyrase tree (BV = 75% and PP = 0.99, Figure 2) in agreement with a revised position of N. equitans based on a recent and more refined phylogenetic analysis of a concatenation of ribosomal proteins (Brochier et al 2005b).…”

Section: Phylogeny Of the Reverse Gyrasementioning

confidence: 99%

Widespread distribution of archaeal reverse gyrase in thermophilic bacteria suggests a complex history of vertical inheritance and lateral gene transfers

Brochier-Armanet

Forterre

2006

Archaea

View full text Add to dashboard Cite

SummaryReverse gyrase, an enzyme of uncertain funtion, is present in all hyperthermophilic archaea and bacteria. Previous phylogenetic studies have suggested that the gene for reverse gyrase has an archaeal origin and was transferred laterally (LGT) to the ancestors of the two bacterial hyperthermophilic phyla, Thermotogales and Aquificales. Here, we performed an in-depth analysis of the evolutionary history of reverse gyrase in light of genomic progress. We found genes coding for reverse gyrase in the genomes of several thermophilic bacteria that belong to phyla other than Aquificales and Thermotogales. Several of these bacteria are not, strictly speaking, hyperthermophiles because their reported optimal growth temperatures are below 80°C. Furthermore, we detected a reverse gyrase gene in the sequence of the large plasmid of Thermus thermophilus strain HB8, suggesting a possible mechanism of transfer to the T. thermophilus strain HB8 involving plasmids and transposases. The archaeal part of the reverse gyrase tree is congruent with recent phylogenies of the archaeal domain based on ribosomal proteins or RNA polymerase subunits. Although poorly resolved, the complete reverse gyrase phylogeny suggests an ancient acquisition of the gene by bacteria via one or two LGT events, followed by its secondary distribution by LGT within bacteria. Finally, several genes of archaeal origin located in proximity to the reverse gyrase gene in bacterial genomes have bacterial homologues mostly in thermophiles or hyperthermophiles, raising the possibility that they were co-transferred with the reverse gyrase gene. Our new analysis of the reverse gyrase history strengthens the hypothesis that the acquisition of reverse gyrase may have been a crucial evolutionary step in the adaptation of bacteria to high-temperature environments. However, it also questions the role of this enzyme in thermophilic bacteria and the selective advantage its presence could provide.

show abstract

“…Carbon-sulfur cycling in a terrestrial mud volcano T-W Cheng et al 16S rRNA gene analysis Genomic DNA for 16S rRNA gene analyses was extracted from 10-g sediments (from 1, 7, 11, 23 and 31 cm of core c3) and the bubbling fluid (ew01), using the UltraClean Mega Soil DNA Isolation Kit (MoBio Laboratories, Carlsbad, CA, USA) according to the manufacturer's instruction, and stored at -20 1C. Nearly complete 16S rRNA gene sequences were amplified on a Robocycler (Stratagene, La Jolla, CA, USA), using a bacterial forward primer B27F and a universal reverse primer U1492R for bacteria (Lane, 1991), and an archaeal forward primer A8F and a universal reverse primer U1513r for archaea (Huber et al, 2002). The PCR protocol and downstream approaches for purification of PCR products, cloning and sequencing were described previously (Lin et al, 2006).…”

Section: Study Site and Sample Collectionmentioning

confidence: 99%

Metabolic stratification driven by surface and subsurface interactions in a terrestrial mud volcano

et al. 2012

View full text Add to dashboard Cite

Terrestrial mud volcanism represents the prominent surface geological feature, where fluids and hydrocarbons are discharged along deeply rooted structures in tectonically active regimes. Terrestrial mud volcanoes (MVs) directly emit the major gas phase, methane, into the atmosphere, making them important sources of greenhouse gases over geological time. Quantification of methane emission would require detailed insights into the capacity and efficiency of microbial metabolisms either consuming or producing methane in the subsurface, and establishment of the linkage between these methane-related metabolisms and other microbial or abiotic processes. Here we conducted geochemical, microbiological and genetic analyses of sediments, gases, and pore and surface fluids to characterize fluid processes, community assemblages, functions and activities in a methane-emitting MV of southwestern Taiwan. Multiple lines of evidence suggest that aerobic/anaerobic methane oxidation, sulfate reduction and methanogenesis are active and compartmentalized into discrete, stratified niches, resembling those in marine settings. Surface evaporation and oxidation of sulfide minerals are required to account for the enhanced levels of sulfate that fuels subsurface sulfate reduction and anaerobic methanotrophy. Methane flux generated by in situ methanogenesis appears to alter the isotopic compositions and abundances of thermogenic methane migrating from deep sources, and to exceed the capacity of microbial consumption. This metabolic stratification is sustained by chemical disequilibria induced by the mixing between upward, anoxic, methane-rich fluids and downward, oxic, sulfate-rich fluids.

show abstract

A new phylum of Archaea represented by a nanosized hyperthermophilic symbiont

Cited by 730 publications

References 23 publications

Origin of life: LUCA and extracellular membrane vesicles (EMVs)

Origin of life: LUCA and extracellular membrane vesicles (EMVs)

Widespread distribution of archaeal reverse gyrase in thermophilic bacteria suggests a complex history of vertical inheritance and lateral gene transfers

Metabolic stratification driven by surface and subsurface interactions in a terrestrial mud volcano

Contact Info

Product

Resources

About