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Maria A Longo - One of the best experts on this subject based on the ideXlab platform.
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north western spain hot springs are a source of lipolytic enzyme producing Thermophilic Microorganisms
Bioprocess and Biosystems Engineering, 2013Co-Authors: Francisco J Deive, Maria S Alvarez, Angeles M Sanroman, Maria A LongoAbstract:Several hot springs in Galicia (North Western Spain) have been investigated as potential sources of lipolytic enzyme-producing Thermophilic Microorganisms. After isolating 12 esterase producing strains, 9 of them were assured to be true lipase producers, and consequently grown in submerged cultures, obtaining high extracellular activities by two of them. Furthermore, a preliminary partial characterization of the crude lipase, obtained by ultrafiltration of the cell-free culture supernatant, was carried out at several pH and temperature values. It is outstanding that several enzymes turned out to be multiextremozymes, since they had their optimum temperature and pH at typical values from thermoalkalophiles. The thermal stability in aqueous solution of the crude enzymes was also assayed, and the influence of some potential enzyme stabilizing compounds was tested. Finally, the viability of the selected Microorganisms has been demonstrated at bioreactor scale.
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decolorization of dye reactive black 5 by newly isolated Thermophilic Microorganisms from geothermal sites in galicia spain
Journal of Hazardous Materials, 2010Co-Authors: Francisco J Deive, A Dominguez, T Barrio, Maria A Longo, F Moscoso, Paloma Moran, M A SanromanAbstract:Abstract In this study, Thermophilic microbial strains from thermal spots in northwestern Spain displaying excellent decolorization capability were isolated. The research work tackled: (i) the ability of consortia to degrade a model di-azo dye Reactive Black at different pHs in flask cultures, obtaining that just neutral pHs licensed degradation levels near to 70%, (ii) the isolation of tree of the bacteria, which rendered possible reaching high levels of decolorization (80%) after just 24 h in aerobic conditions, and which were identified through 16S rRNA sequencing to possess high homology (99%) with Anoxybacillus pushchinoensis , Anoxybacillus kamchatkensis and Anoxybacillus flavithermus , and (iii) the cultivation of the isolates in a bench-scale bioreactor, which led to a decolorization rate two-fold higher than that obtained in flask cultures. Therefore, this work makes up the first time that a decolorization process of an azo dye by Thermophilic Microorganisms in aerobic conditions is investigated.
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Evaluation of a novel Bacillus strain from a north-western Spain hot spring as a source of extracellular thermostable lipase
Journal of Chemical Technology & Biotechnology, 2009Co-Authors: Francisco J Deive, M. Ángeles Sanromán, Maria A LongoAbstract:BACKGROUND: Thermophilic Microorganisms are receiving significant attention as a source of useful thermostable enzymes. However, the number of known strains is still limited, and very often their most interesting biocatalysts are intracellular or membrane-bound and produced at low levels. Thus, the isolation and study of novel extracellular enzyme-producing Thermophilic Microorganisms is very interesting. Moreover, the assessment of bioreactor performance is crucial, given the scarce information on the large-scale culture of these strains. RESULTS: The production of a thermostable extracellular lipase in submerged cultures of a Thermophilic microorganism, recently isolated in north-west Spain, was investigated. The strain was identified by 16S rDNA sequencing as belonging to genus Bacillus. The influence of operating variables (i.e. pH, temperature, aeration) on lipase biosynthesis was analysed. Enzyme production at bioreactor scale was investigated, special attention being paid to the effect of aeration and agitation rates. CONCLUSION: The best conditions for the studied process were determined in shake flasks as pH 7.0, 55 ◦ C and high aeration levels. Also, the non-association between lipase production and cell growth was ascertained. The culture of this novel strain was successfully carried out in laboratory-scale bioreactors, thus proving its potential for further applications. c � 2009 Society of Chemical Industry
Francisco J Deive - One of the best experts on this subject based on the ideXlab platform.
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north western spain hot springs are a source of lipolytic enzyme producing Thermophilic Microorganisms
Bioprocess and Biosystems Engineering, 2013Co-Authors: Francisco J Deive, Maria S Alvarez, Angeles M Sanroman, Maria A LongoAbstract:Several hot springs in Galicia (North Western Spain) have been investigated as potential sources of lipolytic enzyme-producing Thermophilic Microorganisms. After isolating 12 esterase producing strains, 9 of them were assured to be true lipase producers, and consequently grown in submerged cultures, obtaining high extracellular activities by two of them. Furthermore, a preliminary partial characterization of the crude lipase, obtained by ultrafiltration of the cell-free culture supernatant, was carried out at several pH and temperature values. It is outstanding that several enzymes turned out to be multiextremozymes, since they had their optimum temperature and pH at typical values from thermoalkalophiles. The thermal stability in aqueous solution of the crude enzymes was also assayed, and the influence of some potential enzyme stabilizing compounds was tested. Finally, the viability of the selected Microorganisms has been demonstrated at bioreactor scale.
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decolorization of dye reactive black 5 by newly isolated Thermophilic Microorganisms from geothermal sites in galicia spain
Journal of Hazardous Materials, 2010Co-Authors: Francisco J Deive, A Dominguez, T Barrio, Maria A Longo, F Moscoso, Paloma Moran, M A SanromanAbstract:Abstract In this study, Thermophilic microbial strains from thermal spots in northwestern Spain displaying excellent decolorization capability were isolated. The research work tackled: (i) the ability of consortia to degrade a model di-azo dye Reactive Black at different pHs in flask cultures, obtaining that just neutral pHs licensed degradation levels near to 70%, (ii) the isolation of tree of the bacteria, which rendered possible reaching high levels of decolorization (80%) after just 24 h in aerobic conditions, and which were identified through 16S rRNA sequencing to possess high homology (99%) with Anoxybacillus pushchinoensis , Anoxybacillus kamchatkensis and Anoxybacillus flavithermus , and (iii) the cultivation of the isolates in a bench-scale bioreactor, which led to a decolorization rate two-fold higher than that obtained in flask cultures. Therefore, this work makes up the first time that a decolorization process of an azo dye by Thermophilic Microorganisms in aerobic conditions is investigated.
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dye decolourization by newly isolated Thermophilic Microorganisms
Chemical engineering transactions, 2010Co-Authors: Francisco J Deive, A Dominguez, T BarrioAbstract:In this work, various northwestern Spain hot springs have been explored as potential sources of dye-degrading Thermophilic Microorganisms. The sites were selected based on their average water temperature, which was in all cases higher than 50oC. Water and mud samples were collected, and strains isolation were carried out by the streak plate method using a medium supplemented with the model reactive dye, Reactive Black 5. First, the capacity of specific isolated strains and consortia of indigenous Microorganisms to degrade this dye was checked on agar plates. Then, the biological process was carried out in shake flasks, and the decolourization degree provided by each strain and consortium was ascertained through spectrophotometric measurements. Very promising degradation values (around 80%) were detected for some of the assayed consortia, at temperatures of 65oC. The results supported the interest of investigating Thermophilic strains as a potential alternative to mesophilic Microorganisms in microbial dye decolourization.
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Evaluation of a novel Bacillus strain from a north-western Spain hot spring as a source of extracellular thermostable lipase
Journal of Chemical Technology & Biotechnology, 2009Co-Authors: Francisco J Deive, M. Ángeles Sanromán, Maria A LongoAbstract:BACKGROUND: Thermophilic Microorganisms are receiving significant attention as a source of useful thermostable enzymes. However, the number of known strains is still limited, and very often their most interesting biocatalysts are intracellular or membrane-bound and produced at low levels. Thus, the isolation and study of novel extracellular enzyme-producing Thermophilic Microorganisms is very interesting. Moreover, the assessment of bioreactor performance is crucial, given the scarce information on the large-scale culture of these strains. RESULTS: The production of a thermostable extracellular lipase in submerged cultures of a Thermophilic microorganism, recently isolated in north-west Spain, was investigated. The strain was identified by 16S rDNA sequencing as belonging to genus Bacillus. The influence of operating variables (i.e. pH, temperature, aeration) on lipase biosynthesis was analysed. Enzyme production at bioreactor scale was investigated, special attention being paid to the effect of aeration and agitation rates. CONCLUSION: The best conditions for the studied process were determined in shake flasks as pH 7.0, 55 ◦ C and high aeration levels. Also, the non-association between lipase production and cell growth was ascertained. The culture of this novel strain was successfully carried out in laboratory-scale bioreactors, thus proving its potential for further applications. c � 2009 Society of Chemical Industry
Robert M Kelly - One of the best experts on this subject based on the ideXlab platform.
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physiological metabolic and biotechnological features of extremely Thermophilic Microorganisms
Wiley Interdisciplinary Reviews: Systems Biology and Medicine, 2017Co-Authors: James A Counts, Benjamin M Zeldes, Christopher T Straub, Michael W W Adams, Robert M KellyAbstract:The current upper thermal limit for life as we know it is approximately 120°C. Microorganisms that grow optimally at temperatures of 75°C and above are usually referred to as ‘extreme thermophiles’ and include both bacteria and archaea. For over a century, there has been great scientific curiosity in the basic tenets that support life in thermal biotopes on earth and potentially on other solar bodies. Extreme thermophiles can be aerobes, anaerobes, autotrophs, heterotrophs, or chemolithotrophs, and are found in diverse environments including shallow marine fissures, deep sea hydrothermal vents, terrestrial hot springs—basically, anywhere there is hot water. Initial efforts to study extreme thermophiles faced challenges with their isolation from difficult to access locales, problems with their cultivation in laboratories, and lack of molecular tools. Fortunately, because of their relatively small genomes, many extreme thermophiles were among the first organisms to be sequenced, thereby opening up the application of systems biology-based methods to probe their unique physiological, metabolic and biotechnological features. The bacterial genera Caldicellulosiruptor, Thermotoga and Thermus, and the archaea belonging to the orders Thermococcales and Sulfolobales, are among the most studied extreme thermophiles to date. The recent emergence of genetic tools for many of these organisms provides the opportunity to move beyond basic discovery and manipulation to biotechnologically relevant applications of metabolic engineering. WIREs Syst Biol Med 2017, 9:e1377. doi: 10.1002/wsbm.1377 For further resources related to this article, please visit the WIREs website.
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The renaissance of life near the boiling point - at last, genetics and metabolic engineering.
Microbial Biotechnology, 2016Co-Authors: Michael W W Adams, Robert M KellyAbstract:We discuss here the prospects for biotechnology of extreme Thermophilic Microorganisms.
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extremely Thermophilic Microorganisms as metabolic engineering platforms for production of fuels and industrial chemicals
Frontiers in Microbiology, 2015Co-Authors: Benjamin M Zeldes, Matthew W Keller, Andrew J Loder, Christopher T Straub, Michael W W Adams, Robert M KellyAbstract:Enzymes from extremely Thermophilic Microorganisms have been of technological interest for some time because of their ability to catalyze reactions of industrial significance at elevated temperatures. Thermophilic enzymes are now routinely produced in recombinant mesophilic hosts for use as discrete biocatalysts. Genome and metagenome sequence data for extreme thermophiles provide useful information for putative biocatalysts for a wide range of biotransformations, albeit involving at most a few enzymatic steps. However, in the past several years, unprecedented progress has been made in establishing molecular genetics tools for extreme thermophiles to the point that the use of these Microorganisms as metabolic engineering platforms has become possible. While in its early days, complex metabolic pathways have been altered or engineered into recombinant extreme thermophiles, such that the production of fuels and chemicals at elevated temperatures has become possible. Not only does this expand the thermal range for industrial biotechnology, it also potentially provides biodiverse options for specific biotransformations unique to these Microorganisms. The list of extreme thermophiles growing optimally between 70 and 100°C with genetic toolkits currently available includes archaea and bacteria, aerobes and anaerobes, coming from genera such as Caldicellulosiruptor, Sulfolobus, Thermotoga, Thermococcus and Pyrococcus. These organisms exhibit unusual and potentially useful native metabolic capabilities, including cellulose degradation, metal solubilization, and RuBisCO-free carbon fixation. Those looking to design a thermal bioprocess now have a host of potential candidates to choose from, each with its own advantages and challenges that will influence its appropriateness for specific applications. Here, the issues and opportunities for extremely Thermophilic metabolic engineering platforms are considered with an eye towards potential technological advantages for high temperature industrial biotechnology.
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part ii defining and quantifying individual and co cultured intracellular proteomes of two Thermophilic Microorganisms by gelc ms2 and spectral counting
Analytical and Bioanalytical Chemistry, 2010Co-Authors: Genna L Andrews, Robert M Kelly, Derrick L Lewis, Jaspreet S Notey, David C MuddimanAbstract:Probing the intracellular proteome of Thermotoga maritima and Caldicellulosiruptor saccharolyticus in pure and co-culture affords a global investigation into the machinery and mechanisms enduring inside the bacterial Thermophilic cell at the time of harvest. The second of a two part study, employing GeLC-MS2 a variety of proteins were confidently identified with <1% false discovery rate, and spectral counts for label-free relative quantification afforded indication of the dynamic proteome as a function of environmental stimuli. Almost 25% of the T. maritima proteome and 10% of the C. saccharolyticus proteome were identified. Through comparison of growth temperatures for T. maritima, a protein associated with chemotaxis was uniquely present in the sample cultivated at the non-optimal growth temperature. It is suspected that movement was induced due to the non-optimal condition as the organism may need to migrate in the culture to locate more nutrients. The inventory of C. saccharolyticus proteins identified in these studies and attributed to spectral counting, demonstrated that two CRISPR-associated proteins had increased expression in the pure culture versus the co-culture. Further focusing on this relationship, a C. saccharolyticus phage-shock protein was identified in the co-culture expanding a scenario that the co-culture had decreased antiviral resistance and accordingly an infection-related protein was present. Alterations in growth conditions of these bacterial Thermophilic Microorganisms offer a glimpse into the intricacy of microbial behavior and interaction.
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extremely Thermophilic Microorganisms for biomass conversion status and prospects
Current Opinion in Biotechnology, 2008Co-Authors: Sara E Blumerschuette, Michael W W Adams, Robert M Kelly, Irina Kataeva, Janet WestphelingAbstract:Many Microorganisms that grow at elevated temperatures are able to utilize a variety of carbohydrates pertinent to the conversion of lignocellulosic biomass to bioenergy. The range of substrates utilized depends on growth temperature optimum and biotope. HyperThermophilic marine archaea (Topt ≥ 80 °C) utilize α- and β-linked glucans, such as starch, barley glucan, laminarin, and chitin, while hyperThermophilic marine bacteria (Topt ≥ 80 °C) utilize the same glucans as well as hemicellulose, such as xylans and mannans. However, none of these organisms are able to efficiently utilize crystalline cellulose. Among the thermophiles, this ability is limited to a few terrestrial bacteria with upper temperature limits for growth near 75 °C. Deconstruction of crystalline cellulose by these extreme thermophiles is achieved by ‘free’ primary cellulases, which are distinct from those typically associated with large multi-enzyme complexes known as cellulosomes. These primary cellulases also differ from the endoglucanases (referred to here as ‘secondary cellulases’) reported from marine hyperthermophiles that show only weak activity toward cellulose. Many extremely Thermophilic enzymes implicated in the deconstruction of lignocellulose can be identified in genome sequences, and many more promising biocatalysts probably remain annotated as ‘hypothetical proteins’. Characterization of these enzymes will require intensive effort but is likely to generate new opportunities for the use of renewable resources as biofuels.
F Gonzalez - One of the best experts on this subject based on the ideXlab platform.
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bioleaching of a chalcopyrite concentrate with moderate Thermophilic Microorganisms in a continuous reactor system
Hydrometallurgy, 2007Co-Authors: L Cancho, María Luisa Blázquez, Antonio Ballester, F Gonzalez, J A MunozAbstract:Abstract The metal extraction efficiency of bioleaching processes can be greatly improved by using stirred-tank reactors. However, owing to the high cost of acquiring and maintaining these, their use is restricted to the treatment of high-grade ores and concentrates. Unlike gold, the copper industry is not far from achieving commercial implementation of stirred processes on an industrial scale. Recent research has focused on the development of continuous bioleaching processes for the treatment of copper flotation concentrates. The aim of the present work was to optimize a process for continuous bioleaching of chalcopyrite concentrates using moderate Thermophilic Microorganisms and silver ions. The best results were obtained using a series of three reactors under the following experimental conditions: 45 °C, 14 days residence time, 2 g Ag/kg of concentrate (silver deposition stage at 35 °C), stirring rate adjusted to 350 rpm, pH between 1.2 and 1.4 and redox potential between 400 and 500 mV vs. Ag/AgCl. The optimized continuous bioleaching system was able to dissolve copper steadily at a concentration higher than 11 g/L.
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silver catalysed bioleaching of a chalcopyrite concentrate with mixed cultures of moderately Thermophilic Microorganisms
Hydrometallurgy, 1999Co-Authors: Eduardo Perez Gomez, María Luisa Blázquez, Antonio Ballester, F GonzalezAbstract:Abstract Bioleaching of a chalcopyrite concentrate was studied using two mixed cultures of moderately Thermophilic Microorganisms, one from the drainage of Rio Tinto mines and the other obtained by raising the growth temperature of a mixed culture of mesophilic bacteria. Both cultures were adapted to different concentrations of silver (0.1–0.5 g of silver/kg of concentrate) to test their leaching capacity in the presence of this catalyst. The results showed the important role of silver in the chalcopyrite leaching process carried out at 45°C. Copper yields increased around 3-fold over the control experiment without silver. At 50°C, however, only one of the cultures remained active and the effect of silver was masked by strong jarosite precipitation, which increased with the amount of silver used. The 9K medium played a key role in this respect, and it was clear that more diluted media should be used to avoid this problem. Despite this drawback, the amount of copper extracted using the catalyst was double than that obtained without it.
M Bomio - One of the best experts on this subject based on the ideXlab platform.
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physiology and performance of Thermophilic Microorganisms in sewage sludge treatment processes
Biodegradation, 1990Co-Authors: B Sonnleitner, M BomioAbstract:A combined treatment of domestic and industrial liquid wastes is preferably used in most industrialized countries. The primary objective of wastewater treatment plants is a high degree of water purification. But relatively little attention is payed to the primary byproduct, sewage sludge. The economical value of sewage sludge is among the lowest of all materials available on earth, but sludge will undoubtedly continue to be produced in very large quantities in the future. Its effective treatment will be one of the most important problems to solve.
