| the effects of temperature, ph and sulphide on the community structure of hyperthermophilic streamers in hot springs of northern thailand. | hyperthermophilic community diversity was assessed in hot-spring streamers along gradients of temperature, ph and sulphide in northern thailand. a hierarchical sampling design was employed to obtain biomass for culture-independent estimates of 16s rrna gene-defined prokaryotic diversity. all springs supported several archaeal and bacterial phylotypes, including novel phylotypes that expand the known phylogenetic diversity of terrestrial hyperthermophiles. diversity appeared significantly greater ... | 2007 | 17386034 |
| prokaryotic diversity in one of the largest hypersaline coastal lagoons in the world. | araruama lagoon is an environment characterized by high salt concentrations. the low raining and high evaporation rates in this region favored the development of many salty ponds around the lagoon. in order to reveal the microbial composition of this system, we performed a 16s rrna gene survey. among archaea, most clones were related to uncultured environmental euryarchaeota. in lagoon water, we found some clones related to methanomicrobia and methanothermococcus groups, while in the saline pond ... | 2008 | 18427718 |
| microbial community in black rust exposed to hot ridge flank crustal fluids. | during integrated ocean drilling program expedition 301, we obtained a sample of black rust from a circulation obviation retrofit kit (cork) observatory at a borehole on the eastern flank of juan de fuca ridge. due to overpressure, the cork had failed to seal the borehole. hot fluids from oceanic crust had discharged to the overlying bottom seawater and resulted in the formation of black rust analogous to a hydrothermal chimney deposit. both culture-dependent and culture-independent analyses ind ... | 2006 | 17021232 |
| methanococcus aeolicus sp. nov., a mesophilic, methanogenic archaeon from shallow and deep marine sediments. | three strains of co(2)-reducing methanogens were isolated from marine sediments. strain pl-15/h(p) was isolated from marine sediments of the lipari islands, near sicily and the other two strains, nankai-2 and nankai-3(t), were isolated from deep marine sediments of the nankai trough, about 50 km from the coast of japan. analysis of the cellular proteins and 16s rrna gene sequences indicated that these three strains represented a single novel species that formed a deep branch of the mesophilic me ... | 2006 | 16825624 |
| an expanding family of archaeal transcriptional activators. | transcriptional regulation in the archaea involves a mosaic of dna-binding proteins frequently (although not exclusively) of bacterial type, modulating a eukaryal-type core transcription apparatus. methanocaldococcus jannaschii (mja) ptr2, a homologue of the lrp/asnc family of bacterial transcription regulators that are among the most widely disseminated archaeal dna-binding proteins, has been shown to activate transcription by its conjugate hyperthermophilic rna polymerase. here, two in vitro s ... | 2005 | 16230629 |
| archaeal peptidyl prolyl cis-trans isomerases (ppiases) update 2004. | ppiases are ubiquitous in living organisms. while three families of ppiases, cyclophilin (cyp), fk506 binding protein (fkbp) and parvulin (pvn), have been studied in detail in eukarya and bacteria (eubacteria), little is known about archaeal ppiases. among 13 cyclophilins found in archaea, only halobacterium cyclophilin (hbscyp19) has been characterized. this is a cyclosporin a (csa) sensitive cyp with a molecular weight of 19.4 kda. the ppiase activity and csa sensitivity of hbscyp19 is higher ... | 2004 | 14977579 |
| methanothermococcus okinawensis sp. nov., a thermophilic, methane-producing archaeon isolated from a western pacific deep-sea hydrothermal vent system. | a novel thermophilic, methane-producing archaeon was isolated from a deep-sea hydrothermal vent chimney at the iheya ridge, in the okinawa trough, japan. the cells were highly motile, irregular cocci, with a polar bundle of flagella. growth was observed between 40 and 75 degrees c (optimum 60-65 degrees c; 30 min doubling time) and between ph 4.5 and 8.5 (optimum ph 6.7). the isolate was a strictly anaerobic autotroph capable of using hydrogen and carbon dioxide as sole sources of energy and car ... | 2002 | 12148612 |