Read by QxMD icon Read

Extremophiles: Life Under Extreme Conditions

Anke Westphal, Florian Eichinger, Lorenz Eichinger, Hilke Würdemann
Geothermal plants are often affected by corrosion caused by microbial metabolites such as H2 S. In the Bad Blumau (Austria) geothermal system, an increase in microbially produced H2 S was observed in the hot (107 °C) and scaling inhibitor-amended saline fluids and in fluids that had cooled down (45 °C). Genetic fingerprinting and quantification revealed the dominance, increasing abundance and diversity of sulfate reducers such as Desulfotomaculum spp. that accompanied the cooling and processing of the geothermal fluids...
February 18, 2019: Extremophiles: Life Under Extreme Conditions
Marcel Suleiman, Barbara Klippel, Philip Busch, Christian Schäfers, Cyril Moccand, Rachid Bel-Rhlid, Stefan Palzer, Garabed Antranikian
DGGE analysis combined with a metagenomic approach was used to get insights into heterotrophic anoxic enrichment cultures of four hot springs of Vale das Furnas, Portugal, using the recalcitrant substrate spent coffee ground (SCG). Parallel enrichment cultures were performed using the major components of spent coffee ground, namely arabinogalactan, galactomannan, cellulose, and proteins. DGGE revealed that heterotrophic thermophilic bacteria are highly abundant in the hydrothermal springs and significant differences in community composition depending on the substrate were observed...
February 11, 2019: Extremophiles: Life Under Extreme Conditions
Elcia Margareth Souza Brito, Víctor Manuel Romero-Núñez, César Augusto Caretta, Pierre Bertin, Julio César Valerdi-Negreros, Rémy Guyoneaud, Marisol Goñi-Urriza
Vapor steam vents are prevailing structures on geothermal sites in which local geochemical conditions allow the development of extremophilic microorganisms. We describe the structure of the prokaryotic community able to grow on the walls and rocks of such microecosystems in two terrestrial Mexican volcanoes: Paricutín (PI and PII samples) and its satellite Sapichu (S sample). The investigated samples showed similar diversity indices, with few dominant OTUs (abundance > 1%): 21, 16 and 23, respectively for PI, PII and S...
February 2, 2019: Extremophiles: Life Under Extreme Conditions
Asako Suka, Hiroya Oki, Yuki Kato, Kazuki Kawahara, Tadayasu Ohkubo, Takahiro Maruno, Yuji Kobayashi, Sotaro Fujii, Satoshi Wakai, Lisa Lisdiana, Yoshihiro Sambongi
The stability of dimeric cytochrome c' from a thermophile, as compared with that of a homologous mesophilic counterpart, is attributed to strengthened interactions around the heme and at the subunit-subunit interface, both of which are molecular interior regions. Here, we showed that interactions in the equivalent interior regions of homologous cytochromes c' from two psychrophiles, Shewanella benthica and Shewanella violacea (SBCP and SVCP, respectively) were similarly weakened as compared with those of the counterparts of psychrophilic Shewanella livingstonensis and mesophilic Shewanella amazonensis (SLCP and SACP, respectively), and consistently the stability of SVCP, SLCP, and SACP increased in that order...
January 28, 2019: Extremophiles: Life Under Extreme Conditions
Geraldy L S Liman, Tyler Hulko, Hallie P Febvre, Aaron C Brachfeld, Thomas J Santangelo
The sole unifying feature of Archaea is the use of isoprenoid-based glycerol lipid ethers to compose cellular membranes. The branched hydrocarbon tails of archaeal lipids are synthesized via the polymerization of isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP), but many questions still surround the pathway(s) that result in production of IPP and DMAPP in archaeal species. Isotopic-labeling strategies argue for multiple biological routes for production of mevalonate, but biochemical and bioinformatic studies support only a linear pathway for mevalonate production...
January 23, 2019: Extremophiles: Life Under Extreme Conditions
Jan Strejc, Lucie Kyselova, Anna Cadkova, Tomas Potocar, Tomas Branyik
Acidothermophilic bacteria of the genus Alicyclobacillus are frequent contaminants of fruit-based products. This study is the first attempt to characterize the physico-chemical surface properties of two Alicyclobacillus sp. and quantify their adhesion disposition to model materials [diethylaminoethyl (DEAE), carboxyl- and octyl-modified magnetic beads] representing materials with different surface properties used in the food industry. An insight into the mechanism of adhesion was gained through comparison of experimental adhesion intensities with predictions of a colloidal interaction model (XDLVO)...
January 17, 2019: Extremophiles: Life Under Extreme Conditions
Zach A DiLoreto, Tomaso R R Bontognali, Zulfa A Al Disi, Hamad Al Saad Al-Kuwari, Kenneth H Williford, Christian J Strohmenger, Fadhil Sadooni, Christine Palermo, John M Rivers, Judith A McKenzie, Michael Tuite, Maria Dittrich
The Khor Al-Adaid sabkha in Qatar is among the rare extreme environments on Earth where it is possible to study the formation of dolomite-a carbonate mineral whose origin remains unclear and has been hypothetically linked to microbial activity. By combining geochemical measurements with microbiological analysis, we have investigated the microbial mats colonizing the intertidal areas of sabhka. The main aim of this study was to identify communities and conditions that are favorable for dolomite formation. We inspected and sampled two locations...
January 7, 2019: Extremophiles: Life Under Extreme Conditions
Alejandro Arce-Rodríguez, Fernando Puente-Sánchez, Roberto Avendaño, María Martínez-Cruz, J Maarten de Moor, Dietmar H Pieper, Max Chavarría
Here we report the chemical and microbial characterization of the surface water of a CO2 -rich hydrothermal vent known in Costa Rica as Borbollones, located at Tenorio Volcano National Park. The Borbollones showed a temperature surrounding 60 °C, a pH of 2.4 and the gas released has a composition of ~ 97% CO2 , ~ 0.07% H2 S, ~ 2.3% N2 and ~ 0.12% CH4 . Other chemical species such as sulfate and iron were found at high levels with respect to typical fresh water bodies. Analysis by 16S rRNA gene metabarcoding revealed that in Borbollones predominates an archaeon from the order Thermoplasmatales and one bacterium from the genus Sulfurimonas...
January 1, 2019: Extremophiles: Life Under Extreme Conditions
Vitaly V Kadnikov, Andrey V Mardanov, Alexey V Beletsky, Olga V Karnachuk, Nikolai V Ravin
Bacteria of candidate phylum OP8 (Aminicenantes) have been identified in various terrestrial and marine ecosystems as a result of molecular analysis of microbial communities. So far, none of the representatives of Aminicenantes have been isolated in a pure culture. We assembled the near-complete genome of a member of Aminicenantes from the metagenome of the 2-km-deep subsurface thermal aquifer in Western Siberia and used genomic data to analyze the metabolic pathways of this bacterium and its ecological role...
January 1, 2019: Extremophiles: Life Under Extreme Conditions
Regina L Wilpiszeski, Zhidan Zhang, Christopher H House
Built systems such as water heaters can harbor extremophiles similar to those residing in natural hot springs, but the extent of colonization is not well understood. To address this, we conducted a survey of thermophilic microorganisms in household water heaters across the United States. Filter samples and inoculated cultures were collected by citizen-scientists from 101 homes. Draft genomes were assembled from cultured isolates and 16S rRNA genes were sequenced from filter samples. 28% of households harbored communities with unambiguous DNA signatures of thermophilic organisms, 36% of households provided viable inocula, and 21% of households had both...
December 8, 2018: Extremophiles: Life Under Extreme Conditions
Natsuki Takashima, Sonoko Ishino, Keisuke Oki, Mika Takafuji, Takeshi Yamagami, Ryotaro Matsuo, Kouta Mayanagi, Yoshizumi Ishino
DNA polymerase D (PolD), originally discovered in Pyrococcus furiosus, has no sequence homology with any other DNA polymerase family. Genes encoding PolD are found in most of archaea, except for those archaea in the Crenarchaeota phylum. PolD is composed of two proteins: DP1 and DP2. To date, the 3D structure of the PolD heteromeric complex is yet to be determined. In this study, we established a method that prepared highly purified PolD from Thermococcus kodakarensis, and purified DP1 and DP2 proteins formed a stable complex in solution...
November 30, 2018: Extremophiles: Life Under Extreme Conditions
Olga V Golyshina, Rafael Bargiela, Peter N Golyshin
Recently, the order Thermoplasmatales was expanded through the cultivation and description of species Cuniculiplasma divulgatum and corresponding family Cuniculiplasmataceae. Initially isolated from acidic streamers, signatures of these archaea were ubiquitously found in various low-pH settings. Eight genomes with various levels of completeness are currently available, all of which exhibit very high sequence identities and genomic conservation. Co-existence of Cuniculiplasmataceae with archaeal Richmond Mine acidophilic nanoorganisms ('ARMAN')-related archaea representing an intriguing group within the "microbial dark matter" suggests their common fundamental environmental strategy and metabolic networking...
November 29, 2018: Extremophiles: Life Under Extreme Conditions
Eskálath Morganna Silva Ferreira, Francisca Maria Pinheiro de Sousa, Luiz Henrique Rosa, Raphael Sanzio Pimenta
The interest in the diversity of yeasts in the Antarctic environment has increased in recent years, mainly because Antarctic microbiology is a recent science, and little is known about the biodiversity and genetic resources of the microorganisms that inhabit this ecosystem. This study aimed to determine the diversity of epiphytic yeasts in samples of Deschampsia antarctica, Colobanthus quitensis, and bryophytes, as well yeasts present in biofilms collected from Antarctic meltwater. Samples were collected in the summer of 2014 and 2015 during expeditions organized by the Brazilian Antarctic Program...
November 29, 2018: Extremophiles: Life Under Extreme Conditions
C Jeganathan, K Thamaraiselvi, T C Sabari Girisun
Enhanced production and growth of Halobacterium salinarum are achieved by direct supplement of essential amino acids in the modified nutrient culture medium. As arginine (R) and aspartate (D) are the main amino acid sources for producing bacteriorhodopsin efficiently from Halobacterium salinarum, both individual and combined effects of these two amino acids (in different compositions) in the basal medium were studied. The BR production is enhanced by 83% on the eighth day (saturated) for all individual and combined amino acid supplements...
November 26, 2018: Extremophiles: Life Under Extreme Conditions
A Gorlas, R Catchpole, E Marguet, P Forterre
Diverse DNA repair mechanisms are essential to all living organisms. Some of the most widespread repair systems allow recovery of genome integrity in the face of UV radiation. Here, we show that the hyperthermophilic archaeon Thermococcus nautili possesses a remarkable ability to recovery from extreme chromosomal damage. Immediately following UV irradiation, chromosomal DNA of T. nautili is fragmented beyond recognition. However, the extensive UV-induced double-stranded breaks (DSB) are repaired over the course of several hours, allowing restoration of growth...
November 22, 2018: Extremophiles: Life Under Extreme Conditions
Ana M Esteves, Gonçalo Graça, Lindsay Peyriga, Inês M Torcato, Nuno Borges, Jean-Charles Portais, Helena Santos
Pyrococcus furiosus is a remarkable archaeon able to grow at temperatures around 100 °C. To gain insight into how this model hyperthermophile copes with heat stress, we compared transcriptomic and metabolomic data of cells subjected to a temperature shift from 90 °C to 97 °C. In this study, we used RNA-sequencing to characterize the global variation in gene expression levels, while nuclear magnetic resonance (NMR) and targeted ion exchange liquid chromatography-mass spectrometry (LC-MS) were used to determine changes in metabolite levels...
November 14, 2018: Extremophiles: Life Under Extreme Conditions
En-Min Zhou, Wen-Dong Xian, Chrisabelle C Mefferd, Scott C Thomas, Arinola L Adegboruwa, Nathan Williams, Senthil K Murugapiran, Jeremy A Dodsworth, Rakesh Ganji, Meng-Meng Li, Yi-Ping Ding, Lan Liu, Tanja Woyke, Wen-Jun Li, Brian P Hedlund
Thermus species are widespread in natural and artificial thermal environments. Two new yellow-pigmented strains, L198T and L423, isolated from Little Hot Creek, a geothermal spring in eastern California, were identified as novel organisms belonging to the genus Thermus. Cells are Gram-negative, rod-shaped, and non-motile. Growth was observed at temperatures from 45 to 75 °C and at salinities of 0-2.0% added NaCl. Both strains grow heterotrophically or chemolithotrophically by oxidation of thiosulfate to sulfate...
November 2018: Extremophiles: Life Under Extreme Conditions
Scott Wushke, Brian Fristensky, Xiang Li Zhang, Vic Spicer, Oleg V Krokhin, David B Levin, Matthew B Stott, Richard Sparling
A metabolic, genomic and proteomic assessment of Fervidobacterium pennivorans strains was undertaken to clarify the metabolic and genetic capabilities of this Thermotogales species. The type strain Ven5 originally isolated from a hot mud spa in Italy, and a newly isolated strain (DYC) from a hot spring at Ngatamariki, New Zealand, were compared for metabolic and genomic differences. The fermentation profiles of both strains on cellobiose generated similar major end products (acetate, alanine, glutamate, H2 , and CO2 )...
November 2018: Extremophiles: Life Under Extreme Conditions
Chunli Zheng, Li Zhang, Minjie Chen, Xue Qiang Zhao, Yizhuo Duan, Ye Meng, Xuefeng Zhang, Ren Fang Shen
The glutathione synthetase system (GSS) is an important pathway of glutathione synthesis and plays a key role in heavy metal resistance. In this work, the response of Acidithiobacillus ferrooxidans to extracellular Cd2+ was investigated, and the interplay between Cd2+ resistance and the expression of GSS related-genes was analyzed by reverse-transcription quantitative PCR (RT-PCR). During growth in the presence of 5, 15 and 30 mM Cd2+ , the transcript levels of eight GSS pathway genes were affected between 0...
November 2018: Extremophiles: Life Under Extreme Conditions
Angela Casillo, Marcello Ziaco, Buko Lindner, Ermenegilda Parrilli, Dominik Schwudke, Aurora Holgado, Rudi Beyaert, Rosa Lanzetta, Maria Luisa Tutino, Maria Michela Corsaro
Psychrobacter arcticus 273-4 is a Gram-negative bacterium isolated from a 20,000-to-30,000-year-old continuously frozen permafrost in the Kolyma region in Siberia. The survival strategies adopted to live at subzero temperatures include all the outer membrane molecules. A strategic involvement in the well-known enhancement of cellular membrane fluidity is attributable to the lipopolysaccharides (LPSs). These molecules covering about the 75% of cellular surface contribute to cold adaptation through structural modifications in their portions...
November 2018: Extremophiles: Life Under Extreme Conditions
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"