Thermophiles

2022 ◽  
pp. 65-93
Author(s):  
Amitsinh Vijaysinh Mangrola ◽  
Rajesh Kanjibhai Patel ◽  
Pravin Dudhagara ◽  
Himani Gandhi ◽  
Anjana Ghelani ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
High Temperature ◽  
Elevated Temperature ◽  
Hot Springs ◽  
Cellular Functions ◽  
Living Things ◽  
Comprehensive Information ◽  
Metabolism Enzymes ◽  
Shock Proteins ◽  
Physiological Variations

Microorganisms are the diverse living things present on the Earth. India has numerous unique thermal habitats that comprise several diversity hotspots, such as hot springs, deep oceanic hydrothermal openings, anaerobic biodigesters. The existence of life at high temperatures is quite attractive. At both ends of the temperature range suited with life, only microorganisms can grow and survive. Thermophiles are a typical extremophilic microbes capable of existence in high temperature environments. At such high temperature, the ordinary cellular functions adversely affected for mesophiles. The thermophiles effectively manage instability of the plasma membrane, inactivation of enzymes instability of DNA, as well as other hostile physiological variations at such an elevated temperature. Heat shock proteins (Hsps) have established the most attention in thermophiles under stress condition, which is well described in this chapter. This chapter offers comprehensive information about thermophiles, physiology, metabolism, enzymes of metabolic pathways, and various adaptation mechanisms.

Induction of gene expression by heat shock versus osmotic stress

1994 ◽  
Vol 267 (1) ◽  
pp. F28-F34 ◽  
Author(s):  
D. Sheikh-Hamad ◽  
A. Garcia-Perez ◽  
J. D. Ferraris ◽  
E. M. Peters ◽  
M. B. Burg
Keyword(s):  
High Temperature ◽  
Elevated Temperature ◽  
Heat Shock ◽  
Mdck Cells ◽  
Organic Osmolytes ◽  
Hsp 70 ◽  
Expression Of Genes ◽  
High Concentrations ◽  
Shock Proteins ◽  
Darby Canine Kidney

Elevated temperature rapidly increases expression of genes for heat shock proteins (HSP), including HSP-70. The response is presumably triggered by denaturation of cell proteins and helps in their renaturation. Hypertonicity may also denature proteins, but the protective response, which is accumulation of compatible organic osmolytes [including betaine and inositol in Madin-Darby canine kidney (MDCK) cells], apparently differs and is slow. Recently, hypertonicity was found also to increase expression of HSP-70 in MDCK cells, a response proposed to provide protection until organic osmolytes can accumulate. Our purpose was to examine whether 1) a gene involved in accumulation of organic osmolytes also responds to heat stress and 2) whether accumulation of organic osmolytes affects expression of HSP-70. We find that 1) the betaine transporter mRNA, which is greatly increased by hypertonicity (515 vs. 315 mosmol), is unaffected by high temperature (42 degrees C vs. 37 degrees C); 2) hypertonicity-induced increases in HSP-70 and betaine transporter mRNA are much greater when the medium (and cell) contain no betaine and no inositol than when high concentrations of these are present; and 3) high betaine greatly inhibits the increase in HSP-70 mRNA at high temperature. We conclude the following. 1) Although heat shock and betaine transporter genes both respond to hypertonicity, the betaine transporter is not a HSP. 2) Accumulation of organic osmolytes attenuates the HSP-70 response to hypertonicity, as it might if the HSP-70 expression were a temporizing response. 3) Betaine inhibits HSP-70 response to elevated temperature, presumably by its known effect of stabilizing proteins.

Microstructural characterization of a rapidly solidified Al-Fe-V-Si alloy for elevated temperature applications

1988 ◽  
Vol 46 ◽  
pp. 550-551
Author(s):  
R. E. Franck ◽  
J. A. Hawk ◽  
G. J. Shiflet
Keyword(s):  
High Temperature ◽  
Elevated Temperature ◽  
Grain Growth ◽  
Volume Fraction ◽  
Microstructural Characterization ◽  
Second Phase ◽  
Microstructural Stability ◽  
Elevated Temperature Strength ◽  
Temperature Applications

Rapid solidification processing (RSP) is one method of producing high strength aluminum alloys for elevated temperature applications. Allied-Signal, Inc. has produced an Al-12.4 Fe-1.2 V-2.3 Si (composition in wt pct) alloy which possesses good microstructural stability up to 425°C. This alloy contains a high volume fraction (37 v/o) of fine nearly spherical, α-Al12(Fe, V)3Si dispersoids. The improved elevated temperature strength and stability of this alloy is due to the slower dispersoid coarsening rate of the silicide particles. Additionally, the high v/o of second phase particles should inhibit recrystallization and grain growth, and thus reduce any loss in strength due to long term, high temperature annealing.The focus of this research is to investigate microstructural changes induced by long term, high temperature static annealing heat-treatments. Annealing treatments for up to 1000 hours were carried out on this alloy at 500°C, 550°C and 600°C. Particle coarsening and/or recrystallization and grain growth would be accelerated in these temperature regimes.

UDIMET 41

Alloy Digest ◽  
1964 ◽  
Vol 13 (6) ◽  
Keyword(s):  
High Temperature ◽  
Elevated Temperature ◽  
Physical Properties ◽  
Precipitation Hardening ◽  
Base Alloy ◽  
Heat Treating ◽  
Nickel Base Alloy ◽  
Temperature Performance ◽  
Nickel Base ◽  
Corrosion And Oxidation

Abstract UDIMET 41 is a vacuum induction melted precipitation hardening nickel-base alloy having outstanding room and elevated temperature properties. It possesses excellent corrosion and oxidation resistance. It is designed for highly stressed components operating in the 1400-1700 deg F temperature range. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as creep. It also includes information on low and high temperature performance as well as forming, heat treating, machining, and joining. Filing Code: Ni-92. Producer or source: Special Metals Inc..

MO-RE 40MA

Alloy Digest ◽  
1998 ◽  
Vol 47 (12) ◽  
Keyword(s):  
High Temperature ◽  
Elevated Temperature ◽  
Physical Properties ◽  
Tensile Properties ◽  
Oxidation Resistance ◽  
Creep Strength ◽  
Heat Resistant Alloy ◽  
Resistant Alloy ◽  
Heat Resistant ◽  
Temperature Performance

Abstract MO-RE 40MA is a fully austenitic heat-resistant alloy for elevated temperature applications. The alloy is microalloyed for creep strength and oxidation resistance. This datasheet provides information on composition, physical properties, and tensile properties as well as creep. It also includes information on high temperature performance. Filing Code: Ni-548. Producer or source: Duraloy Technologies Inc.

UDDEHOLM QRO 80 MICRODIZED

Alloy Digest ◽  
1987 ◽  
Vol 36 (12) ◽  
Keyword(s):  
Fracture Toughness ◽  
High Temperature ◽  
Elevated Temperature ◽  
Physical Properties ◽  
Tensile Properties ◽  
Tool Steel ◽  
Die Casting ◽  
Heat Treating ◽  
Temperature Performance ◽  
Improved Performance

Abstract UHB QRO 80 MICRODIZED is a chromium-molybdenum-vanadium tool steel with improved performance for tooling used at elevated temperature as in forging, extrusion and die casting. It is electro-slag refined. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fracture toughness. It also includes information on high temperature performance as well as forming, heat treating, machining, and joining. Filing Code: TS-486. Producer or source: Uddeholm Aktiebolag.

J&L TYPE 309

Alloy Digest ◽  
2003 ◽  
Vol 52 (12) ◽  
Keyword(s):  
Stainless Steel ◽  
Corrosion Resistance ◽  
High Temperature ◽  
Elevated Temperature ◽  
Physical Properties ◽  
Heat Treating ◽  
Good Combination ◽  
Resistance To Oxidation ◽  
Cold Worked ◽  
Specialty Steel

Abstract Type 309 (UNS S30900) is an austenitic chromium-nickel stainless steel widely used for elevated-temperature services. It has a good combination of oxidation resistance and corrosion-resisting properties. The alloy is essentially nonmagnetic when annealed and become slightly magnetic when cold worked. It is intended primarily for high-temperature applications at 816 deg C (1500 deg F) or higher where resistance to oxidation and/or corrosion is required. This datasheet provides information on composition, physical properties, hardness, and tensile properties as well as creep. It also includes information on corrosion resistance as well as forming, heat treating, and joining. Filing Code: SS-896. Producer or source: J & L Specialty Steel Inc.

Analysis of Protein-Protein Interaction Networks through Computational Approaches

2020 ◽  
Vol 27 (4) ◽  
pp. 265-278 ◽  
Author(s):  
Ying Han ◽  
Liang Cheng ◽  
Weiju Sun
Keyword(s):  
Protein Interaction ◽  
Biological Networks ◽  
Interaction Networks ◽  
Computational Techniques ◽  
Cellular Functions ◽  
Protein Protein Interaction ◽  
Comprehensive Information ◽  
Protein Interaction Prediction ◽  
Or Gene ◽  
Experimental Findings

The interactions among proteins and genes are extremely important for cellular functions. Molecular interactions at protein or gene levels can be used to construct interaction networks in which the interacting species are categorized based on direct interactions or functional similarities. Compared with the limited experimental techniques, various computational tools make it possible to analyze, filter, and combine the interaction data to get comprehensive information about the biological pathways. By the efficient way of integrating experimental findings in discovering PPIs and computational techniques for prediction, the researchers have been able to gain many valuable data on PPIs, including some advanced databases. Moreover, many useful tools and visualization programs enable the researchers to establish, annotate, and analyze biological networks. We here review and list the computational methods, databases, and tools for protein−protein interaction prediction.

Microstructure of high-temperature (>73 °C) siliceous sinter deposited around hot springs and geysers, Yellowstone National Park: the role of biological and abiological processes in sedimentation

2003 ◽  
Vol 40 (11) ◽  
pp. 1611-1642 ◽  
Author(s):  
Donald R Lowe ◽  
Deena Braunstein
Keyword(s):  
High Temperature ◽  
Yellowstone National Park ◽  
National Park ◽  
Hot Springs ◽  
Strain Effect ◽  
Temperature Sinter ◽  
Architectural Features ◽  
Siliceous Sinter ◽  
High Temperature Sinter

Slightly alkaline hot springs and geysers in Yellowstone National Park exhibit distinctive assemblages of high-temperature (>73 °C) siliceous sinter reflecting local hydrodynamic conditions. The main depositional zones include subaqueous pool and channel bottoms and intermittently wetted subaerial splash, surge, and overflow areas. Subaqueous deposits include particulate siliceous sediment and dendritic and microbial silica framework. Silica framework forms thin, porous, microbe-rich films coating subaqueous surfaces. Spicules with intervening narrow crevices dominate in splash zones. Surge and overflow deposits include pool and channel rims, columns, and knobs. In thin section, subaerial sinter is composed of (i) dark brown, nearly opaque laminated sinter deposited on surfaces that evaporate to dryness; (ii) clear translucent silica deposited subaqueously through precipitation driven by supersaturation; (iii) heterogeneous silica representing silica-encrusted microbial filaments and detritus; and (iv) sinter debris. Brownish laminations form the framework of most sinter deposited in surge and overflow zones. Pits and cavities are common architectural features of subaerial sinter and show concave-upward pseudo-cross-laminations and micro-unconformities developed through migration. Marked birefringence of silica deposited on surfaces that evaporate to dryness is probably a strain effect. Repeated wetting and evaporation, often to dryness, and capillary effects control the deposition, morphology, and microstructure of most high-temperature sinter outside of the fully subaqueous zone. Microbial filaments are abundant on and within high-temperature sinter but do not provide the main controls on morphology or structuring except in biofilms developed on subaqueous surfaces. Millimetre-scale lamination cyclicity in much high-temperature sinter represents annual layering and regular seasonal fluctuations in silica sedimentation.

scholarly journals Carbon Source Preference in Chemosynthetic Hot Spring Communities

2015 ◽  
Vol 81 (11) ◽  
pp. 3834-3847 ◽  
Author(s):  
Matthew R. Urschel ◽  
Michael D. Kubo ◽  
Tori M. Hoehler ◽  
John W. Peters ◽  
Eric S. Boyd
Keyword(s):  
High Temperature ◽  
National Park ◽  
Hot Springs ◽  
Dissolved Inorganic Carbon ◽  
Hot Spring ◽  
Affinity Constant ◽  
Rrna Gene ◽  
Organic Substrates ◽  
Short Term ◽  
Acetate Assimilation

ABSTRACTRates of dissolved inorganic carbon (DIC), formate, and acetate mineralization and/or assimilation were determined in 13 high-temperature (>73°C) hot springs in Yellowstone National Park (YNP), Wyoming, in order to evaluate the relative importance of these substrates in supporting microbial metabolism. While 9 of the hot spring communities exhibited rates of DIC assimilation that were greater than those of formate and acetate assimilation, 2 exhibited rates of formate and/or acetate assimilation that exceeded those of DIC assimilation. Overall rates of DIC, formate, and acetate mineralization and assimilation were positively correlated with spring pH but showed little correlation with temperature. Communities sampled from hot springs with similar geochemistries generally exhibited similar rates of substrate transformation, as well as similar community compositions, as revealed by 16S rRNA gene-tagged sequencing. Amendment of microcosms with small (micromolar) amounts of formate suppressed DIC assimilation in short-term (<45-min) incubations, despite the presence of native DIC concentrations that exceeded those of added formate by 2 to 3 orders of magnitude. The concentration of added formate required to suppress DIC assimilation was similar to the affinity constant (Km) for formate transformation, as determined by community kinetic assays. These results suggest that dominant chemoautotrophs in high-temperature communities are facultatively autotrophic or mixotrophic, are adapted to fluctuating nutrient availabilities, and are capable of taking advantage of energy-rich organic substrates when they become available.

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