Dissertations / Theses on the topic 'Thermophilic bacteria'
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1
Smith, K. "Enzymes of L -malate metabolism : Malate dehydrogenase from porcine heart, mesophilic bacteria and thermophilic bacteria and malate synthase from thermophilic bacteria." Thesis, University of Manchester, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356707.
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Hotten, P. M. "Cellulolysis mediated by some anaerobic thermophilic bacteria." Thesis, University of Reading, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.354080.
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Cramp, Rebecca Ann. "Novel nitrile degrading enzymes in thermophilic bacteria." Thesis, University College London (University of London), 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.300058.
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Lau, Chui-yim. "Ecology of natural thermophilic communities in the Tibet Autonomous Region (China)." Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B38857789.
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Deveci, Haci. "Bacterial leaching of complex zinc/lead sulphides using mesophilic and thermophilic bacteria." Thesis, University of Exeter, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341175.
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Marshall, Rowena Margaret. "Thermophilic acidophilic bacteria : iron, sulphur and mineral oxidation." Thesis, University of Warwick, 1985. http://wrap.warwick.ac.uk/2613/.
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The aim of this study was to investigate the iron- and sulphur-oxidizing activities of thermophilic bacteria with reference to the possible use of such bacteria in the extraction of metals from mineral sulphides. The initial characterization of a range of isolates was based on growth studies with iron and sulphur substrates and on the comparison of whole cell protein electrophoresis patterns. Three groups of bacteria were isolated and studied: moderately thermophilic iron- and mineral sulphide-oxidizing bacteria, moderately thermophilic sulphur oxidizers and extremely thermophilic Sulfolobus-like organisms. Both moderately and extremely thermophilic acidophiles were isolated from hot spring and coal pile samples. The moderately thermophilic iron-oxidizing bacteria and the extreme thermophiles which were examined were sub-divided into three and four sub-groups respectively. In a comparative study of continuous flow iron-oxidation reactors, moderate thermophiles did not produce higher rates of ferric iron production than the mesophile T. ferrooxidans but iron oxidation was less sensitive to inhibition by chloride in a vessel containing a thermophile than in a vessel operating with the mesophile. Iron oxidation during autotrophic growth of moderately thermophilic acidophiles and the rapid dissolution of mineral sulphides during the autotrophic growth of both the moderate and the extreme thermophiles were demonstated, thus considerably increasing the potential industrial significance of these bacteria. The yield of soluble copper from a chalcopyrite concentrate was shown to increase with temperature from relatively low yields with the mesophile T. ferrooxidans, through moderate yields with the moderately thermophilic bacteria to almost complete mineral solubilization with the newly isolated Sulfolobus strains.
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Sislak, Christine Demko. "Novel Thermophilic Bacteria Isolated from Marine Hydrothermal Vents." PDXScholar, 2013. https://pdxscholar.library.pdx.edu/open_access_etds/1486.
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As part of a large study aimed at searching for patterns of diversity in the genus Persephonella along the north to south geochemical gradient of the ELSC, ten novel strains of Alphaproteobacteria were isolated unexpectedly. Using defined media under microaerophilic conditions to enrich for Persephonella from chimney samples collected at the seven vent fields on the ELSC and the dilution to extinction by serial dilution method to purify cultures, a total of ten strains belonging to the Alphaproteobacteria were isolated. Two of these isolates, designate MN-5 and TC-2 were chosen for further characterization and are proposed as two new species of a novel genus to be namedThermopetrobacter. Both strains are aerobic, capable of chemoautotrophic growth on hydrogen and grow best at 55°C, pH 6 and 3.0% NaCl. Strain MN-5 is capable of heterotrophic growth on pyruvate and malate and TC-2 is only able to grow heterotrophically with pyruvate. The GC content of MN-5 is 69.1 and TC-2 is 67 mol%. GenBank BLAST results from the 16S rRNA gene reveal the most closely related sequence to MN-5 is 90% similar and the most closely related sequence to strain TC-2 is 89% similar.
Sampling at a shallow marine vent on the coast of Vulcano Island, Italy in 2007 led to the isolation of a novel species of Hydrogenothermus, a genus within the Hydrogenothermaceae family. This isolate, designated NV1, represents the secondHydrogenothermusisolated from a shallow marine vent. NV1 cells are rod-shaped, approximately 1.5μm long and 0.7μm wide, motile by means of a polar flagellum and grow singularly or in short chains. Cells grow chemoautotrophically using hydrogen or thiosulfate as electron donors and oxygen as the sole electron acceptor. Growth was observed between 45 and 75°C with an optimum of 65°C (doubling time 140 min), pH 4.0-6.5 and requires NaCl (0.5-6.0% w/v). The G+C content of total DNA is 32 mol%.
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Galada, Ncebakazi. "Exploring diversity and ecology of nonarchaea in hydrothermal biotopes." Thesis, University of the Western Cape, 2005. http://etd.uwc.ac.za/index.php?module=etd&.
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The Nanoarchaeota were proposed as the fourth archaeal sub-division in 2002, and the only fully characterized nanoarchaeon was found to exist in a symbiotic association with the crenarchaeote, Ignicoccus sp. This nanoarchaeote, named Nanoarchaeum equitans could not be detected with &ldquouniversal&rdquo
archaeal 16S PCR primers and could only be amplified using specifically designed primers. In order to identify and access a wide diversity of archaeal phylotypes a new set of &ldquo
universal&rdquo
archaeal primers A571F (5&rsquo
-GCY TAA AGS RIC CGT AGC-3&rsquo
) and UA1204R (5&rsquo
-TTM GGG GCA TRC IKA CCT-3&rsquo
) was designed, that could amplify the 16S rRNA genes of all four archaeal sub-divisions. Using these primers community DNA was amplified from Chinese and New Zealand hydrothermal systems.
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Hetzer, Adrian. "Sequestration of metal and metalloid ions by thermophilic bacteria." The University of Waikato, 2007. http://hdl.handle.net/10289/2642.
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This Ph. D. thesis presents results and conclusions from studies 1) investigating the interaction between metal and metalloid ions and thermophilic bacteria, and 2) characterizing microbial populations in a geothermally active habitat with relatively high concentrations of metalloid ions and compounds. In initial cadmium ion toxicity assays, the minimal inhibition concentration for 46 thermophilic bacteria of the genera Aneurinibacillus, Anoxybacillus, Bacillus, Brevibacillus, Geobacillus, and Thermus were determined. The highest tolerances to cadmium ions (Cd2+) in the range of 400 to 3200 micro;M were observed for species belonging to the genus Geobacillus. The thermophilic Gram-positive bacteria Geobacillus stearothermophilus and G. thermocatenulatus were selected to describe further biosorption reactions between cadmium ions and chemically reactive functional groups (potential ligands) within and onto the bacterial cell walls. Data obtained from electrophoretic mobility, potentiometric titration and cadmium ion adsorption experiments were used to quantify the number and concentrations of ligands and to determine the thermodynamic stability constants for the ligand-cation complexes. The first reported surface complexation models (SCMs) quantifying metal ion adsorption by thermophilic microorganisms predicted cadmium adsorption and desorption by both studied Geobacillus strains over a range of pH values and for different biomasses. The results indicated the functional group, with a deprotonation constant pK value of approximately 3.8, to be more dominant in cation biosorption accounting for 66 and 80% of all titrable groups for G. thermocatenulatus and G. stearothermophilus, respectively. The generated SCMs are different from model parameters obtained from mesophilic species that have been studied to date and might indicate a different biosorption behavior for both studied Geobacillus strains. Another objective of this thesis was to characterize microbial populations in the hot spring Champagne Pool, located in Waiotapu, New Zealand. The thermal spring is approximately 65 m in diameter and discharges water at 75eg; C and pH 5.5, which is oversaturated with arsenic and antimony compounds that precipitate and form orange deposits. Recovered nucleic acids and adenosine 5'-triphosphate (ATP) concentrations obtained for Champagne Pool water samples indicated low microbial density and were in good agreement with relatively low cell numbers of 5.6 plusmn; 0.5 x10^6 cells per ml. Denaturing gradient gel electrophoresis (DGGE) and 16S rRNA gene clone library analyses revealed the abundance of Sulfurihydrogenibium, Sulfolobus and Thermofilum-like populations in Champagne Pool. Two novel bacteria and one novel archaeon were successfully isolated with a distant phylogenetic relationship to Sulfurihydrogenibium, Thermoanaerobacter, and Thermococcus, respectively. Genotypic and metabolic characteristics differentiated isolate CP.B2 from described species of the genus Sulfurihydrogenibium. CP.B2 represents a novel genus within the Aquificales order, for which the name Venenivibrio stagnispumantis gen. nov., sp. nov. is proposed. V. stagnispumantis is a thermophilic, chemolithothrophic bacterium, that utilizes molecular hydrogen as electron donor and oxygen as electron acceptor and displayed growth in the presence of up to 8 mM NaAsO2 (As3+) and more than 20 mM Na2HAsO4.7H2O (As5+). However, growth was not observed when Na2HAsO4.7H2O and NaAsO2 were provided as the sole electron acceptor and donor pair. Arsenic resistance was conferred by the genes arsA and arsB
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Clark, Darren Alan. "The study of acidophilic, moderately thermophilic iron-oxidizing bacteria." Thesis, University of Warwick, 1995. http://wrap.warwick.ac.uk/2544/.
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This study has divided the most frequently isolated types of moderate thermophiles into three groups: isolates of Sulfobacillus thermosulfidooxidans (mol% G + C 47-50), an isolate referred to as strain NAL and other closely related species (mol% G+C 54-57), and the type previously referred to as strain TH3 (mol% G+C 68). An enrichment culture was obtained that could efficiently solubilise a range of mineral sulphides at 48oC under air. Characterisation of this culture indicated the presence of two organisms essential for efficient growth under air: a typical S. thermosulfidooxidans group organism (isolate ICH), and a strain TH3 group organism (isolate ICP). Strain ICP appeared to possess an inducible, high affinity transport system for carbon dioxide during growth under air (unlike any previously studied moderate thermophiles), but extensive oxidation of ferrous iron was not achieved even at enhanced carbon dioxide levels. This lack of oxidation appeared to be the result of autotrophically-growth strain ICP having an apparent higher affinity for the end-product of iron oxidation, ferric iron (Ki 0.4 mM), than the substrate, ferrous iron (Km 0.5 mM). Only when a mixed culture of strain ICP and strain ICH was grown did extensive oxidation occur. A comparative mineral leaching study, with a mesophilic, a moderately thermophilic, and an extremely thermophilic culture indicated that the moderately thermophilic culture was the most robust during the dissolution of a range of minerals. This culture gave consistently better mineral dissolution rates than the mesophilic culture, clearly indicating their immediate commercial potential. In comparison the extremely thermophilic culture often produced faster rates of mineral dissolution than the moderately thermophilic culture, but appeared sensitive to agitation at high mineral pulp densities (10% (w/v)), limiting any present commercial applications of these organisms.
11
Cox, Simon Peter. "Iron oxidation and mineral oxidation by moderately thermophilic bacteria." Thesis, University of Warwick, 1992. http://wrap.warwick.ac.uk/109481/.
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The microbial oxidation of minerals is a commercially important process. Until comparatively recently only one organism capable of mineral oxidation has been extensively studied - Thiobacillus ferrooxidans. Several new, potentially commercially important isolates were studied in comparison with T.ferrooxidans. This was done with regard to their iron and sulphur oxidation systems, which are vital to the process of mineral solubilisation, and their ability to solubilise the minerals pyrite or chalcopyrite. The study of the latter was undertaken with particular reference to mixed culture leaching. The effect of growth substrate history on iron and sulphur oxidation varied between organisms. In particular, strain BC1 lost very little of its iron or sulphur oxidation capacity whether it was grown on either substrate. Conversely, the oxidation systems of T.ferrooxidans were directly influenced by growth substrate. SDS PAGE analysis and optical spectroscopy of T.ferrooxidans and strains BC1, LM2 and TH3 were used to investigate iron and sulphur oxidation systems and principally to indicate target components of these systems for further detailed study. Further study of the iron oxidation system in strain BC1 showed that there was only one major chromophore, a membrane bound cytochrome aa_. This had absorption peaks at 443 nm, 560 nm and 604.5 nm. Spectra run at 77°K indicated a shoulder on the Soret peak at approximately 450 nm. Extensive investigation into the effect on the cytochrome aa_ of various detergents culminated in the solubilisation from the membrane of the terminal oxidase in an intact form. This allowed the mid-point redox potential of this cytochrome to be determined as +524 mV. The mid-point redox potentials of T.ferrooxidans cytochrome £ and fi. were determined as +317 mV and +497 mV respectively. SDS PAGE analysis indicated two proteins that could be involved in growth on ferrous iron, at 27 kD and 31 kD. One or both of these proteins appeared to contain very high levels of iron. High levels of iron were also found in fractions from column chromatography which contained cytochrome aa_. Mineral oxidation studies showed that there was a slight increase in the rate of leaching of chalcopyrite in mixed cultures of strain BC1 and strain BC13 when compared to a pure culture of strain BC1, when the organisms where grown in shake flasks. In airlift reactor leaching of chalcopyrite the addition of strain BC13 to strain BC1 had several major effects. The pH in the mixed culture reactor was kept far more constant. Despite this, the leaching of copper from the mineral was not significantly altered in the mixed culture. However, a notable phenomenon in this mixed culture of strain BC1 and strain BC13 was the apparent reduction of the specific iron oxidation capacity of strain BC1 in comparison with its activity in pure culture.
12
Gardner, Murray Newell. "An investigation into the replicon of a broad host range mobilizable plasmid from the moderately thermophilic bacterium Acidithiobacillus caldus." Thesis, Stellenbosch : Stellenbosch University, 2003. http://hdl.handle.net/10019.1/53273.
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Dissertation (PhD)--University of Stellenbosch, 2003.ENGLISH ABSTRACT: The moderately thermophilic (45 to 50DC), highly acidophilic (pH 1.5 to 2.5), chemolithoautotrophic Acidithiobaci/lus caldus strain "f' was isolated from a biooxidation process used to treat nickel ore concentrates. Trans-Alternating Field Electrophoresis (TAFE) analysis of total DNA from the At. caldus cells revealed two plasmids of approximately 14 and 45-kb. The 14-kb plasmid, designated pTC-F14, was cloned and shown by replacement of the cloning vector with a kanamycin resistance gene to be capable of autonomous replication in Escherichia coli. Autonomous replication was also demonstrated in Pseudomonas putida and Agrobacterium tumefaciens LBA 4404 which suggested that pTC-F14 was a broad host-range plasmid. Sequence analysis of the pTC-F14 replicon region revealed five open-reading frames, and a replicon organization like that of the broad host-range IncQ plasmids. Three of the open-reading frames encoded replication proteins with amino acid sequence identities similar to that of the IncQ-like plasmid pTF-FC2 (RepA, 81%; RepB, 78%; RepC, 74%). This high level of relatedness suggested that the two replicons had evolved from a common ancestor. Since closely related replicons are usually incompatible, the compatible replicons of pTC-F14 and pTFFC2 raised the question of how the replicons of the two sister plasmids had evolved such that they can now co-exist in the same host cell line. Further incompatibility testing with the IncQ-like plasmid pIEll08 and the IncQ prototype plasmid RSF10101R11621R300B determined that pTC-F14 was compatible with pIEI108, but incompatible with the IncQ prototype plasmid. It was found that the RepB and RepA replication proteins ofpTF-FC2 and pIEll08 were able to complement the pTC-FI4 orthologs only ifpTC-F14 RepC was present in trans. The RepC protein ofpTC-F14 was thus plasmid-template specific, while the RepA and RepB proteins were less plasmid-template specific. A five nucleotide possible iteron-discriminating region in the direct repeats of IncQ-like plasmid oriV regions has been identified (Tietze, E. (1998) Plasmid 39: 165-181). The iteron sequence ofpTC-F14 differs from pTF-FC2 and pIE 1108 by three nucleotides in this iteron-discriminating region. It was therefore proposed that co-evolution of the iterons and the RepC protein to a point where the RepC protein no longer recognizes the iteron sequence of a closely related sister plasmid is the mechanism by which replicons evolve to become compatible in the same host cell. The incompatibility determinant of the IncQ prototype plasmid RSFlOlOIR11621R300B was also sought, and subsequently localized to the region encoding the IncQ prototype plasmid's repAC genes. Interference with the initiation of pTC-F14 replication by the IncQ prototype plasmid was demonstrated by growth inhibition of a replication-deficient M13 bacteriophage into which oriVpTC-F14 had been cloned. Secondly, the IncQ prototype derivative pKE462 displaced a ColEloriVpTC- F14 construct in complementation assays, and a construct containing only the pTC-F14 repBAC genes similarly displaced the pKE462 plasmid. As the oriVRSFIOIO region was not incompatible with a pTC-F14 replicon, this suggested that it was not the oriV region which was expressing incompatibility, but the products of the IncQ prototype plasmid repAC genes. It is proposed that incompatibility between pTC-F14 and the IncQ prototype plasmid was the consequence of the repAC gene products binding to the iterons of the related rep licon, and that these products are unable to initiate replication. The compatible phenotypes expressed by members of the IncQ plasmid family indicates the inadequacy of using plasmid incompatibility as a classification system. Alignment of the amino acid sequences of the three replication protein orthologs clearly showed that the IncQ plasmid family was divided into two groups. To account for replication protein relatedness and the incompatibility phenotype expressed, it is now proposed that that members of the IncQ family be classified into subdivisions that reflect the different IncQ-like replicons identified in this study. Investigation of pTC-F14 replicon regulation identified a putative promoter sequence which is believed to regulate the initiation of a 5.l-5.7-kb polycistronic transcript that encodes all the replication proteins of the pTC-F14 replicon and the MobB and MobA proteins of the IncP-type mobilization module. The large polycistronic transcript appears to regulated by the RepB protein of the pTC-F14 replicon, and is not subject to cross-regulation by related IncQ plasmids. This suggested that the RepB primase function was not plasmid specific, but that its regulatory function was replicon specific. A second putative promoter sequence identified upstream of the pTC-F14 pasAB operon was, however, cross-regulated by the closely related pTF-FC2 plasmid. The pTC-F14 pas operon encodes two proteins with high amino acid sequence identity (PasA, 81 %; PasB, 72 %) to the plasmid addiction system ofpTF-FC2. This is the second time a plasmid addiction system of this type has been found on an IncQ-like plasmid.
AFRIKAANSE OPSOMMING: Die matig termofiliese (45 to 50°C), hoogs asidofiliese (pH 1.5 to 2.5), chemolitooutotrofiese Acidithiobaci/lus caldus ras "f' is geïsoleer vanaf 'n biooksiderende proses wat gebruik word om gekonsentreerde nikkel-erts te behandel. Trans- Afwisselende Veld Elektroforese (TAVE) analise van totale DNA vanaf die At. caldus selle, het twee plasmiede van ongeveer 14 en 45-kb. onthul. Die 14-kb plasmied, genaamd pTC-F14, is gekloneer en deur vervanging van die kloneringsvektor met 'n kanamisien weerstandsgeen is daar gewys dat hierdie plasmied in staat is tot outonome replikasie in Escherichia coli. Outonome replikasie is ook gedemonstreer in Pseudomonas putida en Agrobacterium tumefaciens LBA 4404 wat suggereer dat pTC-F14 'n wye gasheer-reeks plasmied is. Volgorde analise van die pTC-F14 replikon area het vyf oop leesrame onthul, en 'n replikon organisasie soortgelyk aan dié van die wye gasheer-reeks IncQ plasmiede. Drie van die oop leesrame kodeer vir replikasie proteïene met aminosuur volgordes ooreenstemmend met dié van die IncQ-tipe plasmied pTF-FC2 (RepA, 81%; RepB, 78%; RepC, 74%). Hierdie hoë vlak van verwantskap stel voor dat die twee replikons vanaf 'n gemeenskaplike voorouer ontwikkel het. Aangesien naby-verwante replikons gewoonlik onverenigbaar is, het die verenigbaarheid van die replikons van pTC-F14 en pTF-FC2 die vraag laat onstaan van hoe die replikons van twee susterplasmiede ontwikkel het, sodat hulle nou gelyktydig in dieselfde gasheer sellyn kan voortbestaan. Verdere onverenigbaarheid toetsing van die IncQ-tipe plasmied pIE1108 en die IncQ prototipe plasmied RSF10101R11621R300B, het bepaal dat pTCF14 verenigbaar is met pIE1108, maar onverenigbaar met die IncQ prototipe plasmied. Daar is gevind dat die RepB en RepA replikasie proteïene van pTF-FC2 en pIE1108 in staat was om die pTC-F14 ortoloë te komplementeer, slegs as pTC-F14 RepC in trans teenwoordig was. Die RepC proteïen van pTC-F14 is dus plasmiedtemplaat spesifiek, terwyl die RepA en RepB proteïene minder plasmied-templaat spesifiek is. 'n Moontlike iteron-onderskeidende vyf-nukleotied area in die direkte herhalings van die IncQ-tipe plasmied oril/ areas, is geïdentifiseer (Tietze, E. (1998) Plasmid 39: 165-181). Die iteron volgorde van pTC-F14 verskil van pTF-FC2 en pIEll08 met drie nukleotiedes in hierdie iteron-onderskeidende area. Om hierdie rede is daar voorgestel dat ko-evolusie van iterons en die RepC proteïen, tot by 'n punt waar die RepC proteïen nie meer die iteron volgorde van 'n naby-verwante susterplasmied herken nie, die meganisme is waardeur replikons ontwikkel om verenigbaar te word in dieselfde gasheersel. Die onverenigbaarheidsbepaler van die IneQ prototipe plasmied RSFIOIOIR11621R300B is ook ondersoek en gelokaliseer tot die area wat kodeer vir die IneQ prototipe plasmied se repAC gene. Inmenging met die inisiasie van pTC-F14 replikasie deur die IneQ prototipe plasmied is gedemonstreer deur groei vertraging van 'n replikasie-gebrekkige M13 bakteriofaag waarin die oriVpTC-F14 gekloneer is. Tweedens is die ColEl-oriVpTc-FI4 konstruk vervang deur die IneQ prototipe-afgeleide pKE462 in komplementasie proewe, en is die pKE462 plasmied op soortgelyke wyse vervang deur 'n konstruk wat slegs die pTC-F14 repBAC gene bevat. Aangesien die oriVRSF1010 area nie verenigbaar was met 'n pTC-F14 replikon nie, stel dit voor dat dit nie die oriV area is wat onverenigbaarheid uitdruk nie, maar die produkte van die IneQ prototipe plasmied se repAC gene. Dit is voorgestel dat onverenigbaarheid tussen pTC-F14 en die IneQ prototipe plasmied die gevolg is van die repAC geenprodukte wat bind aan die iterons van die verwante replikon en dat hierdie produkte nie in staat is om replikasie te inisieer nie. Die verenigbare fenotipes wat deur die lede van die IneQ plasmied familie uitgedruk word, dui aan op die ontoereikendheid van die gebruik van plasmied onverenigbaarheid as 'n klassifikasie sisteem. Vergelyking van die aminosuur volgordes van die drie replikasie proteïen ortoloë wys duidelik daarop dat die IneQ plasmied familie in twee groepe verdeel is. Om verantwoording te doen vir die replikasie proteïen verwantskap en die onverenigbare fenotipe wat uitgedruk is, word daar nou voorgestel dat die lede van die IneQ familie geklassifiseer word in subafdelings wat die verskillende IneQ-tipe replikons geïdentifiseer in hierdie studie, reflekteer. Ondersoek na die pTC-F14 replikon regulering het 'n moontlike promotor volgorde geïdentifiseer. Daar word gemeen dat hierdie promotor die inisiasie van 'n 5.l-5.7-kb polisistroniese transkrip reguleer, wat kodeer vir al die replikasie proteïene van die pTC-F14 replikon en die MobB en Mob A proteïene van die IneP-tipe mobilisasie module. Die groot polisistroniese transkrip blyk om gereguleer te word deur die RepB proteïen van die pTC-F14 replikon, en word nie gekruis-reguleer deur die IneQ plasmiede nie. Dit stel voor dat die RepB primase se funksie nie plasmiedspesifiek is nie, maar dat die reguleerbare funksie replikon-spesifiek is. 'n Tweede moontlike promotor volgorde wat stroom-op van die pTC-F14 pasAB operon geïdentifiseer is, is egter gekruis-reguleer deur die pTF-FC2 plasmied. Die pTC-F14 pas operon kodeer vir twee proteïene met hoë aminosuur volgorde verwantskappe (PasA, 81 %; PasB, 72 %) aan die plasmied-verslaafde sisteem van pTF-FC2. Dit is die tweede keer dat hierdie tipe plasmied-verslaafde sisteem in 'n IncQ-tipe plasmied gevind is.
13
Haas, R. Matthew. "Synthesis and characterization of phosphono-CheY from Thermotoga maritima /." Electronic version (PDF), 2007. http://dl.uncw.edu/etd/2007-1/haasr/rmatthewhaas.html.
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14
Okibe, Naoko. "Moderately thermophilic acidophiles and their use in mineral processing." Thesis, Bangor University, 2002. https://research.bangor.ac.uk/portal/en/theses/moderately-thermophilic-acidophiles-and-their-use-in-mineral-processing(9c8b82ee-27ad-453e-baf6-9afb284c7735).html.
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This research project focused on moderately thermophilic acidophilic microorganisms and their role in the oxidation of pyrite. A major objective of the work was to assess the relative efficiencies of defined combinations of moderate thermophiles in oxidising pyrite under defined conditions. In addition, various aspects of the physiology and phylogeny of moderately thermophilic acidophiles were investigated. Moderately thermophilic acidophiles, including novel acidophiles (a thermotolerant Leptospirillum and a Ferroplasma sp. ), were isolated from a commercial stirred-tank pilot plant. Pyrite oxidation by mixed cultures of different combinations of moderate thermophiles, including the novel isolates, was assessed in preliminary shake flask experiments. Data from these experiments were used to select microbial consortia in later experiments in temperature- and pH-controlled bioreactors. These involved monitoring rates of mineral oxidation, and relative numbers of the different microorganisms included in the original inoculum, using a plating technique in conjunction with a molecular approach (FISH). The results from the pyrite oxidation studies indicated that mixed populations of acidophiles may accentuate or diminish the rates and extent of pyrite oxidation, relative to pure cultures. The thermotolerant Leptospirillum isolate was found to be unable to oxidise a pyrite concentrate when grown in pure culture, though this inhibition was overcome when the iron-oxidiser was grown in mixed cultures with various Grampositive acidophiles. Investigation of the effects of fifteen individual and mixtures of flotation chemicals on moderately thermophilic acidophiles revealed different degrees of toxicities of the different reagents and sensitivities of the microorganisms, with the Leptospirillum isolate generally being the most sensitive of those tested. The phenomenon of pH-related ferric iron toxicity to moderately thermophilic and mesophilic Gram-positive bacteria was also investigated. ARDREA (Amplified Ribosomal DNA Restriction Enzyme Analysis) using the 16S rRNA gene sequences of known acidophilic bacteria, was refined and developed, and applied successfully to identify moderate thermophiles isolated from environmental samples.
15
Heinrich, Hannah Tabea Monika, and n/a. "Acid-base and Cd�⁺ adsorption properties of two thermophilic bacteria." University of Otago. Department of Chemistry, 2007. http://adt.otago.ac.nz./public/adt-NZDU20080107.095128.
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The release of toxic metal species is of concern due to their detrimental effects on the environment and human health. Industrial effluents are a major source of mobilised metal species. Suitable technologies are needed to sequester toxic metal species at the point of source. Biosorption, which is based on the passive adsorption of contaminants onto biological materials, promises to offer an effective alternative or complementary step to existing treatment methods. However, to date there has been no widespread commercialisation of the technique. This is partly due to an insufficient understanding of the complex underlying mechanisms which makes it difficult to select suitable biomass for specific remediation problems and to predict process performance.
This study characterised two gram-positive, thermophilic bacteria, Anoxybacillus flavithermus (BF) and Geobacillus stearothermophilus (BS), harvested at two different growth times, with regard to their acid-base and Cd�⁺ adsorption behaviour. The aim was to investigate the metal cation adsorption properties of thermophilic bacteria which has not been studied previously, and to gain a better understanding of the interactions responsible for bacterial metal cation adsorption. Experimental techniques employed in this study included microscopy to establish cell and cell wall morphology, batch acid-base and Cd�⁺ adsorption experiments to quantify proton active surface functional groups and Cd�⁺ adsorption, electrophoretic mobility measurements to assess the overall surface charge of the bacteria and in situ attenuated total reflection infrared (ATR-IR) spectroscopy to reveal the chemical identities of functional groups. Chemical equilibrium models based on batch acid-base titration and electrophoretic mobility data were developed to quantitatively describe proton active surface functional groups. These groups can also interact with metal cations.
It was found that growth time was an important factor in all experiments with the differences between growth times often being more pronounced than the differences between the two bacterial strains. Microscopy revealed a gram-positive cell wall structure with different widths and staining behaviour for exponential phase cells of BF and BS. Stationary / death phase cells showed disintegrating cell walls. Acid-base titrations indicated that all cells possessed buffering capacity over the whole investigated pH range (pH 2 - 10). From electrophoretic mobility measurements, isoelectric points of ~ 3.2 for BF and < 1.8 and ~ 4.2 for exponential and stationary / death phase cells of BS respectively were estimated. Chemical equilibrium models including a Donnan electrostatic model were derived which described both the batch acid-base titration data and the electrophoretic mobility data reasonably well, although a comparison with IR data suggested room for further improvement. In situ ATR-IR spectroscopy of hydrated bacterial cells at various pH values revealed amide and carboxyl groups and a contribution from phosphate / polysaccharide moieties. Group specific interactions with Cd�⁺ were not detected, however, a partially reversible absorbance increase of all peaks suggested conformational changes in the presence of Cd�⁺. BF and BS adsorbed ~ 70 [mu]mol Cd�⁺ (g dry bacterial)⁻� at pH 5 in 0.01 M NaNO₃. Release of major cations occurred concomitantly with Cd�⁺ adsorption.
The buffering and Cd�⁺-binding capacities of BF and BS were found to be comparable to those of mesophilic bacteria and ion exchange was identified as an important adsorption mechanism.
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Elvin, Mark. "Production and structure of exopolysaccharides from thermophilic lactic acid bacteria." Thesis, University of Huddersfield, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368301.
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Walsh, Sally. "The isolation and starvation-survival of thermophilic sulphate-reducing bacteria." Thesis, University of Exeter, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307293.
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Duvenage, Wineen. "Detection and isolation of thermophilic acidophilic bacteria from fuit juices." Thesis, Stellenbosch : University of Stellenbosch, 2006. http://hdl.handle.net/10019.1/3016.
Full textAbstract:
Thesis (Msc Food Sc (Food Science))--University of Stellenbosch, 2006.Fruit juices were until recently considered to only be susceptible to spoilage by yeasts, mycelial fungi and lactic acid bacteria. Spoilage by these organisms was prevented by the acidic pH of fruit juices and the heat-treatment applied during the hot-fill-hold process. Despite these control measures, an increasing number of spoilage cases of fruit juices, fruit juice products and acidic vegetables due to contamination by thermophilic acidophilic bacteria (TAB) have been reported. The genus Alicyclobacillus, containing TAB were first classified as Bacillus, but were reclassified in 1992. Species of Alicyclobacillus are Gram-positive, rod-shaped, endospore-forming bacteria. The unique characteristic of these organisms is the presence of ω-alicyclic fatty acids, such as ω-cyclohexane and ω-cycloheptane, as the major components of the cellular membrane. This organism has been shown to survive pasteurisation conditions of 95°C for 2 min and grows within a pH range of 2.5 to 6.0 and temperatures between 25° and 60°C. The genus currently consists of 11 species, with A. acidoterrestris, A. acidocaldarius and A. pomorum being the only species associated with the spoilage of fruit juices and fruit juice products. The aim of this study was to evaluate culture-dependent and culture-independent approaches for the detection and isolation of Alicyclobacillus spp. from pasteurised South African fruit juices and concentrates. The culture-dependent approach was evaluated by comparing five different growth media, for growth and recovery of A. acidoterrestris, A. acidocaldarius and A. pomorum at different incubation temperatures, from sterile saline solution (SSS) (0.85% (m/v) NaCl), diluted and undiluted fruit juice concentrates. The five media evaluated included potato dextrose agar (PDA), orange serum agar (OSA), K-agar, yeast extract (YSG)-agar and Bacillus acidocaldarius medium (BAM). The culture-independent approach was used to identify the micro-organisms present in fruit juices and concentrates from different South African manufacturers before and after pasteurisation, using polymerase chain reaction (PCR)-based denaturing gradient gel electrophoresis (DGGE) and DNA sequencing. Spread plates of PDA at pH 3.7 and incubation temperature of 50°C for 3 days was found to be the best isolation media for species of Alicyclobacillus from fruit juice and fruit juice concentrate. With the inclusion of a heat shock treatment at 80°C for 10 min the growth media of preference for spores of Alicyclobacillus from fruit juice concentrates was OSA at pH 5.5 and an incubation temperature of 50°C for 3 days. The culture-dependent approach could detect cells or endospores at a minimum concentration of 104 cfu.ml-1 in SSS and diluted fruit juices. PCR-based DGGE analysis was more sensitive and detected cells of Alicyclobacillus spp. from fruit juices and concentrates at a minimum concentration of 103 cfu.ml-1. Alicyclobacillus acidoterrestris was found to be present in South African apple juice, pear juice, white grape juice and aloe vera juice. White grape juice was also found to contain A. pomorum. Other organisms present in the orange, apple, mango and pear juices were two uncultured bacteria that were identified as members of the genus Bacillus, and one uncultured bacterium closely related to Alcaligenus faecalis. This study confirmed the presence of TAB in pasteurised South African fruit juices and concentrates and emphasises the need for the rapid and accurate detection of TAB in food products.
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Ястремська, Лариса Сергіївна, and Катерина Миколаївна Яблонська. "Wastewater treatment and energy carier producing by thermophilic anaerobic association." Thesis, National Aviation Universitty, 2013. http://er.nau.edu.ua/handle/NAU/38606.
Full textAbstract:
With sewage сardboard-рaper enterprise Kyiv isolated of technologically promising thermophilic (60 oC) anaerobic microbe association that consists of cellulolytic and methanogenic bacteria. Within 4-5 days association completely destroys the cellulose and synthesizes the first hydrogen and later methane. Besides methane is also formed ethanol, acetate, propionate, butyrate. When using anaerobic аssociation in wastewater cleaning сardboard - рaper enterprise, chemical consumption oxygen decreases by three times
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Mackay, Dale Tara. "Characterisation of Sulfolobus solfataricus Ard1, a promiscuous N-acetyltransferase." Thesis, St Andrews, 2008. http://hdl.handle.net/10023/468.
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Mavengere, William Nyasha. "The structure, function and engineering of a thermostable nitrile hydratase." Thesis, University of the Western Cape, 2008. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_4827_1271013260.
Full textAbstract:
Nitrile hydratases (NHases) are enzymes that catalyse the conversion of organocyanides to amides via a non-hydrolytic hydration reaction. They are industrially relevant enzymes, currently used in the manufacture of nicotinamide and acrylamide. The target of this study belongs to the thermophilic bacteria Geobacillus pallidus.
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Rahman, Thahira J. "The diversity and distribution of thermophilic bacteria in cool soil environments." Thesis, University of Ulster, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.422883.
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Patel, Sejal. "A novel thermostable restriction modification system." Thesis, University College London (University of London), 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321773.
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Summit, Melanie. "Ecology, physiology, and phylogeny of subseafloor thermophiles from mid-ocean ridge environments /." Thesis, Connect to this title online; UW restricted, 2000. http://hdl.handle.net/1773/11020.
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Deutschman, William A. "Structural and thermodynamic basis of the thermostability of CheY from the extreme thermophile Thermotoga maritima /." view abstract or download file of text, 2001. http://wwwlib.umi.com/cr/uoregon/fullcit?p3018362.
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Thesis (Ph. D.)--University of Oregon, 2001.Typescript. Includes vita and abstract. Includes bibliographical references (leaves 147-155). Also available for download via the World Wide Web; free to University of Oregon users.
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Khandekar, Sanjay S. "Purification and characterization of fumarate reductase from Methanobacterium thermoautotrophicum." PDXScholar, 1986. https://pdxscholar.library.pdx.edu/open_access_etds/490.
Full textAbstract:
Anaerobic fermentation has been an established technology ever since man started treating sewage. Recently this process has received increased attention because of its inherent ability to produce methane gas, which apart from solar energy, is the cleanest, most non-polluting source of energy. Methanobacterium thermoautotrophicum, a thermophilic bacterium, grows on CO(,2) as a source of carbon as well as electron acceptor, using hydrogen as an electron donor. Labeling studies carried out with ('14)C have shown a presence of partial reductive TCA cycle. In this work, the enzyme fumarate reductase, which belongs to this cycle, has been purified to homogeneity using various separation techniques. In keeping with the thermophilic character of the organism, fumarate reductase is extremely heat resistant. Incubation at 75(DEGREES)C for 24 hours led to an increase in purification. In contrast, the enzyme was found to be very sensitive to oxygen. The crude extract, when exposed to air, lost half of its activity within 20 minutes. Reducing agents were helpful in protecting against loss of enzymatic activity provided that a strict anaerobic atmosphere was maintained. For this reason, the entire purification was performed inside a Freter-type anaerobic chamber using reducing agents. The molecular weight of the native fumarate reductase, as determined by Sephacryl S-300 gel exclusion chromatography, was found to be approximately 80,000. SDS polyacrylamide gel electrophoresis data suggested that the enzyme is a tetramer. Treatment with sulfhydyl reagents as well as Cu('++) caused loss in fumarate reductase activity, indicating that the enzyme contains at least one sulfhydryl group which is important to its activity. The UV/Visible spectrum of fumarate reductase did not reveal the presence of a flavin moiety as a cofactor. Both UV/Visible and fluorescence spectra of fumarate reductase from M. thermoautotrophicum instead, indicated the presence of an unusual cofactor, which could be similar to either tetrahydromethanopterin or F(,420).
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Yavuz, Elif Yenidünya Ali Fazıl. "Genotypic characterization of extracellular enzyme producing thermophilic bacteria in Balçova geothermal region/." [s.l.]: [s.n.], 2003. http://library.iyte.edu.tr/tezler/master/biyoteknoloji/T000270.pdf.
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Alonaizi, Thnayan. "Heavy Metal Bioremediation by Anaerobic-Thermophilic Bacteria from the Great Artesian Basin." Thesis, Griffith University, 2019. http://hdl.handle.net/10072/386067.
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Bioremediation is considered an effective environmental remedial strategy when compared with physical and chemical techniques. Microorganisms can remove and detoxify pollutants by transforming or degrading them. A large portion of these toxic pollutants are heavy metals that are present naturally or due to anthropogenic activities. Bacteria inhabiting areas that have high levels of heavy metals have adapted to resist and reduce these pollutants. In the current, study heavy metal transforming bacteria have been isolated, characterised and investigated for bioremediation and biodegradation capabilities.
The Great Artesian Basin (GAB) in Australia is a unique thermal site that harbours diverse microbial communities. Anaerobic and facultative anaerobic, thermophilic and thermotolerant bacteria were isolated from groundwaters and run-off waters from the GAB region. A total of 6 bacteria were isolated and identified as belonging to Anoxybacillus, Thermobrachium, Caloramator, and Virgibacillus genera using the 16S rRNA.
Heavy metal reduction capacity was tested on all of the isolates. Strain VY was best at reducing vanadium(V), up to 10mM. Strain COY reduced up to 8 mM of cobalt(III). Strain SEY showed the most significant reduction of selenium(III). Strain FEY had the highest extent of iron(III) reduction. Strains CRG and CRL could reduce chromium(VI) most efficiently. Additional tests were done to fortify the selection of an optimal candidate for heavy metal bioremediation. These tests included biosurfactant production, for which all strains exhibited at least a 32% reduction in surface tension after 24 hours. The second test was biofilm formation where strains SEY and CRG performed best forming a medium rated biofilm under aerobic conditions but a poor biofilm under anaerobic conditions. A third test was to measure the chemotactic ability of the strains and strain SEY demonstrated the ability to possess a chemical attraction towards iron(III).
From the characterisation tests and regarding bioremediation potential, strain SEY, an Anoxybacillus sp., was the most promising. This isolate had improved vanadium(V) and iron(III) reduction rates of over 50% in co-cultivation symbiosis tests with strains CRL and FEY, respectively.Thesis (Masters)
Master of Science (MSc)
School of Environment and Sc
Science, Environment, Engineering and Technology
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Chung, Wai-chung Denis. "Comparison of performance of thermophilic and mesophilic UASB reactors treating protein-rich wastewater /." Hong Kong : University of Hong Kong, 1997. http://sunzi.lib.hku.hk/hkuto/record.jsp?B20665738.
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Grassia, Gino Sebastian, and n/a. "The isolation, growth and survival of thermophilic bacteria from high temperature petroleum reservoirs." University of Canberra. Applied Science, 1995. http://erl.canberra.edu.au./public/adt-AUC20060712.131412.
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The microbial ecology of 45 high temperature (> 50 ° C) petroleum reservoirs was
investigated by isolating and characterizing bacteria that were present in their produced
fluids. Initial work was aimed at selecting a suitable high temperature petroleum
reservoir for the study of natural microbial populations. Experimental work then
focussed on establishing the physico-chemical conditions that prevail in the selected
reservoir and on developing media and enrichment conditions for the isolation of
microorganisms indigenous to the reservoir. The ability of reservoir bacteria to grow
and survive under the physical and chemical conditions found in the selected reservoir
was used to assess the likelihood of an indigenous origin for these bacteria.
The petroleum reservoir selected for study was the Alton petroleum reservoir (SW
Queensland, Australia). It was established that most of the physico-chemical conditions
in the Alton reservoir had remained unchanged since oil recovery began. The stability
of redox conditions (90 mV) in the reservoir over its operating life was identified as an
important factor in the coexistence of strict aerobic and strict anaerobic bacterial
populations within the reservoir. An important change that has occurred in the Alton
reservoir over its operating life because of oil recovery was an increase in water pH
from 6.41 to 8.42 as a result of carbon dioxide loss (1.36 atm to 0.0134 atm) from the
reservoir.
Development of novel enrichment procedures that simulated Alton reservoir conditions
led to the isolation of previously unreported aerobic and anaerobic populations of
thermophilic bacteria. The aerobic bacteria isolated were identified as either endosporeforming
heterotrophic bacteria from the genus Bacillus or nonspore-forming
heterotrophic bacteria resembling members of the genus Thermoleophilum. All aerobes
grew on carbon sources such as acetate and n-heptadecane that are normal constituents
of the reservoir. The anaerobic bacteria isolated were characterized as sheathed
fermentative bacteria from the order Thermotogales or non-sheathed fermentative
bacteria. In parallel studies, the natural microbial populations in other reservoirs were
investigated and I concluded that fermentative microorganisms were common
inhabitants of high temperature petroleum reservoirs. The isolation of fermentative
bacteria from these high temperature petroleum reservoirs established that fermentative
bacteria are a fourth major microbial group, together with hydrocarbon-oxidizers,
sulphate-reducers and methanogens, to be reported in petroleum reservoirs. The
fermentative bacteria use organic nutrients and carbohydrates, but not contemporary
crude oil as the principal nutrient source within reservoir waters.
The thermophilic bacteria isolated from Alton petroleum reservoir demonstrated growth
characteristics such as temperature (optima 50-70 ° C and range 37-85 ° C), pH (optima
6.0-9.0 and range 5.0-9.0 and salinity (optima 0-15 g per litre and range 0-30 g per
litre), that were consistent with conditions encountered in the Alton reservoir
(temperature 75 � C, pH 8.5 and TDS 2.7 g per litre). The isolated bacteria also
demonstrated a number of characteristics that might enable them to survive adverse
conditions that could be encountered in a petroleum reservoir environment. The
characteristics that contribute to aerobic bacteria surviving in and overcoming periods
of oxygen limitation include well-documented processes such as sporulation, by
Bacillus spp., and microaerophily. The characteristics that contribute to fermentative
bacteria surviving were: (1) a natural tolerance to reservoir physico-chemical
fluctuations, (2) an ability to remain viable when metabolic activity was suppressed to
very low rates by the growth-limiting conditions imposed, and (3) possible formation of
viable ultramicrobacteria (UMB). Formation of UMB (bacteria smaller than 0.3 |im) by
thermophilic bacteria has not been reported previously.
The recovery of thermophilic UMB by filtration from the Alton reservoir water
indicates that these bacteria occur in natural habitats. This study found the formation of
thermophilic UMB and their survival characteristics differed considerably from that
reported for the mesophilic, marine bacterium Vibrio sp. DWI. Unlike mesophilic
marine bacteria, thermophilic bacteria did not always respond to nutrient deprivation by
forming UMB and that these UMB did not show any increased ability to survive in the
face of adverse conditions. Although the formation of UMB as part of routine cell
growth and division was not demonstrated directly in this study, circumstantial
evidence suggests that they form part of a natural life cycle. The exact conditions that
result in UMB formation and their role in survival remain unresolved.
The capacity of nonspore-forming indigenous populations from Alton to survive sudden
shifts in environmental conditions that might result from common oilfield operations
was poor. Such operations were demonstrated to be inhibitory or lethal to Alton
reservoir bacteria. It also was concluded that such oilfield operations suppress
indigenous microbiota. However, the impacts of most oilfield operations within a
reservoir are likely to be confined to the immediate area surrounding injection and
producing wells. Minimizing the localized effects of oilfield practices on indigenous
reservoir populations will lead to the better management of undesirable microbial
activity in reservoirs such as H2S formation (souring) and facilitate development of
better microbially mediated oil recovery process. This study showed that selected
reservoir isolates possess characteristics which are suitable for in situ biotechnological
applications such as microbially enhanced oil recovery (MEOR). Characteristics
favourable for enhanced oil recovery include a capability for UMB formation, which
would enable better dispersion, and resistance to high concentrations of reservoir
components such as calcium, magnesium, strontium, heavy metals and hydrocarbons.
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Munaka, Matshaya. "Characterisation of a lignocellulosic degrading bacillus strain isolated from thermophilic compost." University of the Western Cape, 2011. http://hdl.handle.net/11394/5373.
Full textAbstract:
>Magister Scientiae - MScThe negative environmental impact of fossil fuels and growing concerns about petroleum supplies has driven the search for alternative, renewable transportation fuels. An 'ideal' fuel replacement would be a biofuel produced from lignocellulosic biomass. Unfortunately, the presence of lignin in plant cell walls impedes the breakdown of cell wall polysaccharides into simple sugars and the subsequent conversion of these sugars into useable fuels. One of the most common fates of lignin in nature is to be metabolized by lignin peroxidases (LiPs), predominantly of microbial origin. This study aims to isolate and characterise microorganism(s) involved in the degradation of lignocellulose. Thermophilic bacteria were isolated from straw-based compost and screened for lignin peroxidase activity. One isolate, CP11, showed significant lignin peroxidase activity and based on 16S rRNA gene sequence analysis, the isolate was found to be most closely related to Bacillus thermoamylovorans. Morphological, physiological and biochemical characterisation was conducted to determine whether the isolate was a novel species. Morphologically, CP11 was characterised as an endospore-forming, Gram positive rod. In addition, the isolate was found to be a facultative anaerobe, catalase positive and capable of utilising a range of carbon sources including glucose, sucrose and arabinose. Isolate CP11 was moderately thermotolerant and grew between 37°C and 55°C, with an optimum growth temperature of 45°C. Based on its phenotypic characteristics CP11 could be clearly distinguished from its closest phylogenetic neighbours. Preliminary characterisation of the lignin peroxidase was conducted using crude enzyme extract and Azure B dye as the substrate. Activity was detected in the supernatant only and a growth curve was constructed to determine the growth phase of lignin peroxidase production. In order to identify the gene encoding the lignin peroxidase a small insert library was constructed and screened for ligninase activity using Azure B as the substrate.
National Research Foundation
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鍾偉聰 and Wai-chung Denis Chung. "Comparison of performance of thermophilic and mesophilic UASB reactorstreating protein-rich wastewater." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1997. http://hub.hku.hk/bib/B31215221.
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Janosch, Claudia [Verfasser], Wolfgang [Akademischer Betreuer] Sand, and Bettina [Akademischer Betreuer] Siebers. "Sulfur oxidation in moderately thermophilic leaching bacteria / Claudia Janosch. Gutachter: Bettina Siebers. Betreuer: Wolfgang Sand." Duisburg, 2013. http://d-nb.info/1042934614/34.
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Garip, Sebnem. "The Characterization Of Bacteria With Fourier Transform Infrared(ftir) Spectroscopy." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606673/index.pdf.
Full textAbstract:
New and rapid techniques for the characterization and identification of
bacteria would have an important role in clinical microbiology and in food
analysis because of an increasing prevalence of infectious diseases and
In this work we carried out two approaches. In the first study the
characterization and differentiation of mesophilic and thermophilic
bacteria were investigated by using Fourier Transform Infrared (FTIR)
Spectroscopic technique. In the second study, we investigated the
characterization and identification of 3 Bacillus and Micrococcus species
Our results from first approach show that there was a dramatic
difference between mesophilic and thermophilic bacteria. The protein
concentration was high, lipid concentration, the level of triglycerides and the unsaturated acyl chains decreased in thermophilic bacteria. We
found that in thermophilic bacteria PO-
2 groups become hydrogen
bounded. In addition, our results suggest that the cellular DNA content
was low in thermophilic bacteria.
Moreover there were characteristic peaks for both mesophilic and
thermophilic bacteria and these peaks can be used for the differentiation
of these two bacteria group. There were also some specific peaks that
can be used for the differentiation of Escherichia coli and Lactobacillus
plantarum at species level.
In the second approach, our results show that there were significant
spectral differences between Bacillus and Micrococcus species such as
the proportion of unsaturated acyl chains in triglycerides were higher in
Micrococcus species. Moreover we observed different bands that may
be explained by an acetate oxidation via the tricarboxylic acid cycle and
an exopolymer formation in Micrococcus species. In addition to that
another band similar to glycogen, may be explained by a glycogen-like
storage material in Micrococcus species. Also there are characteristic
peaks that can be used for identification of Micrococcus spp.
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Lau, Chui-yim, and 劉翠艷. "Ecology of natural thermophilic communities in the Tibet Autonomous Region (China)." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B38857789.
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Wright, Mitchell Henry. "Physiological and Molecular Investigations of Manganese Transforming Bacteria." Thesis, Griffith University, 2014. http://hdl.handle.net/10072/368137.
Full textAbstract:
Bacteria plays a critical role in the geochemical cycling of manganese in aquatic environments. They are readily able to transform manganese through oxidative and reductive processes. In natural environments, it is well known that some bacteria are able to oxidise Mn(II) to Mn(IV) under aerobic conditions, while others reduce Mn(IV) to Mn(II) under anaerobic conditions. In the current project, manganese transforming bacteria were investigated on both a physiological and molecular basis to further understand bacterial transformation.
Paralana hot springs (PHS), an aqueous environment rich in heavy metals, was used as a model environment in the study. The diversity of microorganisms in PHS was initially investigated using both culture dependent and independent techniques. Metagenomic 16S rRNA screening revealed bacteria belonging to 24 different phyla, 11 of which have been previously determined to contain manganese oxidisers. Mesophilic and thermophilic bacteria were detected and isolated, with many able to oxidise and/or reduce manganese as well as other metals (including iron, arsenic, cobalt, manganese, molybdenum, selenium, uranium and vanadium). Subsequent 16S rRNA analysis of obtained isolates revealed a number of novel bacteria, including the manganese transforming bacteria; Bacillus sp. DLH-1207, Bacillus sp. PMO and Paenibacillus sp. AEM-1106.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Biomolecular and Physical Sciences
Science, Environment, Engineering and Technology
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Soo, Rochelle. "Microbial Biodiversity of Thermophilic Communities in Hot Mineral Soils of Tramway Ridge, Mt. Erebus, Antarctica." The University of Waikato, 2007. http://hdl.handle.net/10289/2441.
Full textAbstract:
Only a few studies have looked at microbial biogeography in soils and whether microorganisms are endemic to an area is still debatable. Tramway Ridge, a geothermal area on Mount Erebus, Antarctica, provides a unique opportunity due to its isolation and extreme conditions to explore the possibilities of microbial endemism and to identify novel Bacteria and Archaea. This site was chosen for a culture-independent study with a preliminary culturing survey for bacterial communities along three temperature gradients (65 C - 2.5'C). In addition, a physico-chemical analysis was undertaken to identify which environmental factors were driving the different diversity along the transects. An automated rRNA intergenic spacer analysis (ARISA) was used to assess the diversity across the transects using Bacteria and Cyanobacteria-specific primers and results showed that temperature and pH were the main drivers for these communities. Due to its unique physico-chemical and ARISA profile, a hot temperature site (T-3A, 65'C) was chosen for further investigation by bacterial and archaeal 16S rDNA clone libraries. Unique rDNA types among the 78 bacterial and 83 archaeal clones were identified by restriction fragment length polymophisms and 18 bacterial and 5 archaeal operational taxonomic units (gt97% identity) were observed. All of the bacterial sequences were deeply branching and loosely affiliated with other recognised bacterial divisions, with 40% of the sequences not affiliated to any genus. The archaeal clones were found to be deep-branching and sequences clustered together within the Crenarcaheota. In addition, two strains of Bacilli were isolated. The novel microorganisms show that the Tramway Ridge communities are unique from organisms found in other environments and show that quotEverything is (not) everywherequot.
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Habgood, Robert. "Investigating the potential of producing alkanes and other fatty acid-derived biofuels using the thermophilic chassis Geobacillus thermoglucosidasius." Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/50494/.
Full textAbstract:
Diminishing fossil fuel reserves and the drawbacks of conventional crop-based biofuels has catalysed recent research into the microbial conversion of lignocellulosic biomass into liquid biofuel. Fatty acids represent the most abundant form of reduced carbon chain in nature, and represent the basic building blocks for the creation of a wide-range of advanced biofuels; such as alkanes, fatty alcohols, and fatty acid methyl- and ethyl-esters. It is hoped that the use of a thermophilic platform strain, that is capable of producing fatty acid-derived biofuels at elevated temperatures, will circumvent some of the challenges faced by established mesophilic organisms such as Escherichia coli or Saccharomyces cerevisiae. Here we describe the heterologous expression of an alkane biosynthesis pathway from the thermophilic cyanobacteria Thermosynechococcus elongatus BP-1 in both E. coli and the thermophilic production organism Geobacillus thermoglucosidasius. Alkane biosynthesis in T. elongatus BP-1 is facilitated by two enzymes: fatty acyl-ACP reductase (AAR) and aldehyde deformylating oxygenase (ADO): both of which were found to demonstrate a level of activity in vivo at mesophilic and thermophilic temperatures (30 - 52°C). Expression of an alkane biosynthesis operon in G. thermoglucosidasius NCIMB 11955 resulted in the production of ~100 mg OD-1 L-1 fatty alcohols, and an inconsistent formation of minute amounts of heptadecane. Improved titres of alkane may be achievable through the identification and elimination of competing pathways, and a better understanding of n-alkane biodegradation in G. thermoglucosidasius. However, we recommend the continued pursuit of fatty alcohol production using G. thermoglucosidasius as a host. Elimination of several fatty acid degradation (fad) genes in G. thermoglucosidasius was undertaken with the hope of showing an ability to manipulate the cellular pool of fatty acyl-ACP substrates available to the alkane biosynthesis pathway. The combined elimination of two long-chain-fatty-acid—CoA ligase genes (fadD1 and fadD2) resulted in increased levels of pentadecanoic- and heptadecanoic acid. The heterologous expression of a fatty acyl-ACP thioesterase (FAT) from Clostridium thermocellum and from the Aminicenantes candidate phylum (OP-8) was also undertaken in an attempt to manipulate levels of cellular FFAs, although we postulate that observation of a differential phenotype requires the development of a strain completely defunct of long-chain-fatty-acid—CoA ligase activity. Fatty acid metabolism in G. thermoglucosidasius represents a complex myriad of multiple genes that are subject to strong homeostasis. Nevertheless, we present evidence that genetic manipulations of G. thermoglucosidasius are sufficient to bring about changes in the fatty acid profile of cells, and encourage the further genetic characterization of fatty acid metabolism in the organism through targeted gene deletions, with the hope of producing an improved platform strain for fatty alcohol and alkane biosynthesis at thermophilic temperatures.
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Holden, James Francis. "Ecology, diversity, and temperature-pressure adaptation of the deep-sea hyperthermophilic Archaea Thermococcales /." Thesis, Connect to this title online; UW restricted, 1996. http://hdl.handle.net/1773/11044.
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St, John Emily Joyce. "Symbiosis in Archaea: Functional and Phylogenetic Diversity of Marine and Terrestrial Nanoarchaeota and their Hosts." PDXScholar, 2019. https://pdxscholar.library.pdx.edu/open_access_etds/4939.
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The Nanoarchaeota are an enigmatic lineage of Archaea found in deep-sea hydrothermal vents and geothermal springs across the globe. These small (~100-400 nm) hyperthermophiles live ectosymbiotically with diverse hosts from the Crenarchaeota. Despite their broad distribution in high-temperature environments, very few Nanoarchaeota have been successfully isolated in co-culture with their hosts and nanoarchaeote genomes are poorly represented in public databases. However, the Nanoarchaeota provide unique insights into the structure and function of symbiosis in the archaeal domain. This study describes novel nanoarchaeotes from multiple geothermal habitats, using a combination of direct cultivation techniques and genomic analysis. A new nanoarchaeote from a New Zealand hot spring, Candidatus Nanoclepta minutus, was isolated in co-culture with its host. Like other terrestrial Nanoarchaeota, Cand. Ncl. minutus harbors genes for gluconeogenesis and archaeal flagella. Zestosphaera tikiterensis, the New Zealand host, was also isolated in pure culture and characterized. Phylogenetic analysis showed that both Cand. Ncl. minutus and Z. tikiterensis are new genera in the Nanoarchaeota and Crenarchaeota, respectively. Metagenome-assembled genomes (MAGs) from the Nanoarchaeota were also recovered from deep-sea hydrothermal vent sites. These MAGs capture a wide range of diversity in the Nanoarchaeota, representing three new species and two novel genera. Key nanoarchaeotal features were identified in the MAGs, including marker genes for archaeal flagella, gluconeogenesis and CRISPR-Cas regions. These studies greatly contribute to our understanding of nanoarchaeotal ecophysiology and provide key insights into the coding potential and diversity of Nanoarchaeota and their hosts.
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Ewart, D. Keith. "Studies on a moderately thermophilic mixed culture of bacteria and its application to the biooxidation of gold-bearing minerals." Thesis, King's College London (University of London), 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389882.
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Ikrényiová, Terézia. "Komplementární analýza prokaryotických buněk pomocí elektronové mikroskopie a Ramanovy spektroskopie." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2021. http://www.nusl.cz/ntk/nusl-445147.
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This master thesis deals with conventional methods of bacterial cell analysis, polyhydroxyalkanoates, Raman spectroscopy and electron microscopy in the theoretical part. The production of polyhydroxybutyrate by selected thermophilic bacteria and their analysis by gas chromatography, cryogenic scanning electron microscopy and Raman spectroscopy is described in the experimental part. The chosen sample was analyzed by a transmission electron microscope. Comparing the results from previous mentioned methods it was found that the bacteria Schlegelella thermodepolymerans accumulated the highest amount of PHB. The lowest amount of PHB was obtained by bacteria Rubrobacter xylanophilus. The assumption that the PHB granules formed so-called needle-like plastic deformations during freeze-fracturing was affirmed by cryo-SEM photos analysis. Moreover, it was found that the bacterial cell characterization deduced from microscopic observation of samples corresponded to the description in the literature. TEM provided better resolution photos and in consequence the cells and PHB are more visible. The thesis is also focused on chemical fingerprint analysis of cells by Raman spectroscopy. Several biomolecules were identified by measured Raman spectra for the particular samples.
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Varmužová, Tamara. "Biodegradace s využitím termofilních mikroorganismů." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2009. http://www.nusl.cz/ntk/nusl-216455.
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This thesis is focused on study of biodegradability of modified polyurethane elastomeric films in synthetic medium with minerals and vitamins on tempered shaker by mixed thermophilic aerobic bacterial culture Bacillus and Thermus genera. In most cases addition of all used fillers (carboxymethyl cellulose, hydroxyethyl cellulose, acetylated cellulose, acetylated starch and glutein) led to increased biodegradability of elastomeric films with modifying agent in comparison with elastomeric films without modifying agent (referential). The growth of cultures was strongly increased in presence of elastomeric films modified by 10 % acetylated cellulose and 10 % carboxymethyl cellulose. Elastomeric film biodegradation mechanism included probably two stages: abiotic destruction of elastomeric films and consequent utilization of degradation products by bacterial culture.
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Aldosary, Huda A. KH. "Polycyclic Aromatic Hydrocarbon Degradation by Anaerobic Bacteria from the Great Artesian Basin." Thesis, Griffith University, 2020. http://hdl.handle.net/10072/393639.
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The Great Artesian Basin (GAB) is a vast subterranean thermal aquifer system underlying over 20% of the Australian continent. Substantial reserves of oil, gas and minerals exist within the GAB and combined with industrial activities can often contaminate the groundwaters. The current study investigated the bacterial ecology of bore waters that were in or close to oil deposits. Three sites were selected, two in the Quilpie/Eromanga region of Queensland (Naretha bore registered number 4022 and Adavale bore registered number 305), and the other in the Moomba oil field of South Australia (Moomba bore 9). A wide diversity of bacteria was detected across all of the samples collectively, including members of 32 bacterial phyla. There was greater diversity in the water samples from bores 4022 and 305 compared with Moomba 9, which was likely due to its closer association with oil. The most dominant bacterial taxa were similar in bores 4022 and 305, families Rhodobacteraceae, and Xanthomonadaceae and the order Bacillales. In contrast, the dominant taxa from Moomba 9 were the family Oxalobacteriaceae and the genus Agrococcus. Three different water samples were tested from bore 4022, from the source, 100 m and 250 m downstream in the runoff channel water. The bacterial diversity increased the further away the water flowed from the bore, due to the cooler water and contamination from the surrounding environment.
A comprehensive anaerobic thermophilic enrichment program revealed that bacteria grew on a wide variety of organic substrates and a range of heavy metals as terminal electron acceptors. Isolation yielded 164 bacteria capable of using substrates from sugars and extracts through to polycyclic aromatic hydrocarbons (PAH) and reducing the metals iron(III), vanadium(V), cobalt(III) and manganese(IV). Seven pure iron(III) reducing polycyclic aromatic hydrocarbon (PAH) degrading bacteria, designated strains RN40AT, RN40BT, RN40CT, RN40DT, RN305AT, RN305BT and MBA9BT, were selected for further studies. The rates of degradation Polycyclic Aromatic Hydrocarbon Degradation by Anaerobic Bacteria from the Great Artesian Basin and PAH preference varied significantly between the isolates. Strain MBA9BT showed the highest extent (97.6%) of anthracene degradation while strain RN305BT was the lowest (9.7%). Again, strain MBA9BT also showed the highest extent (91.2%) of pyrene degradation and strain RN40DT showed the lowest (16.1%). Phenanthrene degradation was highest in strain RN40BT and the lowest in strain MBA9BT (2%). PAH degradation in all the isolates showed a direct dependence on Fe(III) reduction. A measurable decrease in the surface tension of the medium suggested the production of biosurfactants by all isolates when grown with PAHs as substrates.
Genomic analysis of the isolates revealed subsystems of different pathways that are commonly found in metal acquisition, transport and utilisation as well as those for aromatic hydrocarbon degradation. Strain RN40DT had the highest number of genes involved in the metabolism of PAHs, though all of the isolates had genes for the metabolism of central aromatic intermediates, especially those related to catechol, salicylate and homogentisate degradation. The isolates had varying levels of genes involved in the metabolism and resistance to iron, copper, chromium, zinc, molybdenum, manganese and mercury. Strains RN40AT, RN305AT RN305BT, RN40BT and RN40DT contained the most genes for iron acquisition and metabolism including those for siderophores, hemin transporters and ferric ABC transport systems.
The results in the current study have built upon our understanding of bacterial diversity in the GAB, particularly with insights into waters associated with oil deposits. Bacteria that degrade polycyclic aromatic hydrocarbons with the simultaneous reduction of Fe(III) under anaerobic conditions were isolated for the first time and may have significant potential in bioremediation of contaminated groundwaters.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environment and Sc
Science, Environment, Engineering and Technology
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Pernicová, Iva. "Identifikace a izolace PHA produkujících bakterií." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2021. http://www.nusl.cz/ntk/nusl-438296.
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Polyhydroxyalkanoates (PHA) are microbial storage polyesters that represent a renewable and environmentally friendly alternative to petrochemical plastics. However, their production and use are severely disadvantaged by the high production cost. The use of extremophilic PHA producers is one of the ways to reduce the cost of PHA production. Extremophiles bring numerous advantages resulting from the high robustness of the process against microbial contamination. In this doctoral thesis, attention was focused on the study of PHA production using selected halophilic and thermophilic microorganisms. Representatives of the genus Halomonas were mainly from public collections of microorganisms. Two promising PHA producers on waste frying oil were identified, namely Halomonas hydrothermalis and Halomonas neptunia. Both strains achieved good PHA yields in flask experiments. With the addition of suitable structural precursors, they were also able to produce copolymers with interesting material properties. However, in the proposed thesis, the main emphasis was placed on the study of PHA production using thermophilic microorganisms. As a part of the work, the isolation of thermophilic PHA producers from various thermophilic consortia (active sludge, compost, etc.) was performed. During isolations experiments, an original isolation procedure was designed using changes in osmotic pressure, the so-called osmoselection. Dozens of promising thermophilic PHA producers were obtained thanks to this original approach. They were taxonomically classified using 16S rRNA and tested for production potential. The most promising PHA producer was the isolate which was classified as Aneurinibacillus sp. H1. This bacterium is able to utilize a variety of substrates, including waste glycerol, to produce PHA. Even more important is the capability of synthesizing copolymers with a high content of 4-hydroxybutyrate. The monomer composition of the PHA copolymer and thus the material properties of the prepared copolymer can be controlled by suitable adjustment of the cultivation conditions. The prepared copolymer P(3HB-co-4HB) has unique properties and the great application potential in numerous high-end applications, for example in the field of health care, food industry or cosmetics.
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Dunn, Helen Diane. "Characterisation of exopolysaccharides from thermophilic strains of lactic acid bacteria and their relationship to the texture of fermented milk." Thesis, University of Huddersfield, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.247393.
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Kirumira, Abdullah K. "Direct microbiological conversion of cellulosic biomass to fuel ethanol by a simultaneous saccharification/fermentation process using thermophilic anaerobic bacteria." Thesis, Kirumira, Abdullah K. (1989) Direct microbiological conversion of cellulosic biomass to fuel ethanol by a simultaneous saccharification/fermentation process using thermophilic anaerobic bacteria. PhD thesis, Murdoch University, 1989. https://researchrepository.murdoch.edu.au/id/eprint/52689/.
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The major objective of this thesis was to investigate and improve a direct microbial fermentation process, using the thermophilic anaerobic bacteria Clostridium thermocellum and Clostridium thermohvdrosulfuricum for the production of fuel ethanol in economically significant concentrations, from cellulose and hemicellulose contained in renewable biomass. Two model substrates representative of readily available lignocellulosic materials were selected for this study. These were wheat straw, which is the largest single biomass resource available in Australia, and waste paper, which is a major component of municipal solid wastes.
At the onset of the research, proximate analyses of the composition of the two substrates were carried out to assess the potential yield of ethanol. Based on the total carbohydrate (hexose as well as pentose sugars) content of the materials, a theoretical potential yield of ethanol over 500 litres per dry tonne of biomass was estimated for both substrates. The feasibility of effecting biomass conversion to ethanol by direct fermentation of the substrates was then examined.
Fermentation characteristics of 9 strains of the potent cellulolytic anaerobe, C. thermocelIum and 5 strains of the saccharolytic ethanoloaen. C. thermohvdrosulfuricum. were investigated on a range of sugars. Cellulose hydrolysis and fermentation by C. thermocellum strains were also studied with alpha-cellulose and the two model substrates. Variations in growth characteristics, extent and rates of substrate utilization, as well as in the stoichiometry of product formation were noted, not only between the two species, but also among the different strains. A stable coculture comprising the most potent strains of the two species could be established, and this culture efficiently fermented crystalline and native cellulosic substrates to produce ethanol at substantially higher yields than could be achieved with cultures of C. thermocellum alone. At 1% (w/v) concentration of wheat straw and newspaper, ethanol yield amounting to 70% of theoretical was obtained with the coculture, compared to 25% of theoretical yield exhibited bv C. thermocellum. The metabolic basis for the enhanced fermentation effectiveness of the coculture system has been discussed.
The feasibility of attaining higher ethanol concentrations in the fermentations was investigated next by employing increased substrate concentrations in batch as well as fed-batch mode of operation. The bioconversion efficiency was observed to systematically decrease with increased substrate concentration, and a limiting ethanol concentration for the cocultures appeared to be around 10-12g/l. At the highest substrate loadings used, the yield of ethanol was only 25% of theoretical. Lignaceous components of biomass and inhibition of bacterial growth by products of fermentation, as well as the physical nature of the substrates were determined to be the major factors limiting the effectiveness of the fermentation.
The above observations led to further studies involving a comparative evaluation of range of substrate delignification treatments and a systematic program of strain improvement with respect to increased ethanol tolerance and end product selectivity. A selective solvent extraction procedure using an alkaline ethanol solvent yielded the best delignification performance of all the alternatives examined. Up to 70% lignin removal with a loss of less than 10% of the available carbohydrates was obtained with this method. Coculture fermentation of wheatstraw and newspaper pretreated by this procedure showed a four-fold increase in the maximum volumetric degradation rate as well as nearly 100% increase in the overall extent of substrate utilization, compared to untreated material.
Studies aimed at improving the fermentation efficacy were undertaken on both species of organisms. Improved ethanol tolerance was achieved through progressive adaptation of parent strains to higher ethanol concentrations in the growth medium. The strains isolated in this work however tended to have a significantly higher yield of the acid products concomitant with their enhanced ethanol productivity. A separate program of mutation and selective isolation of low acid producing cultures eventually resulted in strains which in coculture, fed batch fermentations were able to produce ethanol at concentrations of up to 30g/l at a net ethanol yield exceeding 60% of theoretical, when grown on pretreated wheat straw and newspaper.
A relatively reduced yield of ethanol however, was noted on real biomass compared to similar fermentations using pure substrates. This coincided with increased production of acetate with the crude substrates. An analysis of fermentation kinetics for the various experiments revealed that the ethanol/acetate ratio for deregulated strains of C. thermocellum and C. thermohvdrosulfuricum was strongly dependent on the specific growth rate the organisms achieve during fermentation, which, in turn is determined by the substrate hydrolysis and/or consumption rates. The implications of this to future process improvement studies has been briefly discussed.
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França, Lucas Vagueiro de. "Macroalgae as feedstock for cultivation of marine bacteria." Master's thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/14921.
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Mestrado em Biotecnologia - Biotecnologia Industrial e AmbientalAlginate, laminarin and mannitol amount up to 60% of dry weight in brown macroalgae. The presence of alginate and laminarin-degrading enzymes and mannitol metabolic machinery have been confirmed by Matís, a partner in European BlueGenics project. Thus, in a biorefinery perspective, R. marinus can potentially perform the saccharification and fermentation of brown macroalgae carbohydrates to yield commercial valuable biocompounds, as thermostable enzymes and glycosidic carotenoids. Rhodothermus marinus is a moderate thermophilic (65ºC) and slight halophilic (1.0% NaCl) marine bacterium. Therefore, one of the objectives of this project was to decrease the NaCl concentration in the fermentation medium, since chloride leads to a lower equipment lifetime due to stainless steel corrosion of bioreactors. The main objective of this work was the study of the bacterium R. marinus pattern of growth when cultivated in the main brown macroalgal carbohydrates. This work was performed with five R. marinus strains, two of which were successfully acclimatized to cultivation in Medium 166, cryopreserved in glycerol and recultivated in liquid media, being subject of study in the assays with different carbon and sodium sources in shake flask. The growth studies with different carbon sources suggested that (i) strain 5 presented higher glucose consumption and growth, even though none of the strains consumed all the glucose available in the media; (ii) although none of strains consumed mannitol, strain 5 seemed to be more robust to its presence; and (iii) the growth differences between the controls and the assays with alginate and pretreated alginate were not significant enough to infer if any alginate consumption occurred. It was tested a partial and total substitution of NaCl by Na2SO4. The process was not successful, since Na2SO4 seem to represent a stress factor to both R. marinus strains. Interestingly, the strain 5, when cultivated in Medium 166 containing only a half of NaCl standard concentration, presented a similar growth pattern to control. In the operational conditions imposed in shake flask cultivations containing two tested brown macroalgae (orginial and pretreated) as feedstock for growth, mannitol was not consumed. It was not possible to monitor the alginate and laminarin saccharification and fermentation. Although, the results showed that brown macroalgae are a potential feedstock under the biorefinery concept, since some R. marinus growth was observed. The more promising result to BlueGenics project was obtained from shake flask cultivations of strain 5 in Medium 166 with 0.500% NaCl and 10.0 g.L-1 glucose, since the growth with low chloride content determinates the feasibility of the scale-up of the process to bioreactor . Because of that, the assay was validated in 3L controlled bioreactor. The process presented a μmax of 0.208 h-1, a maximum biomass concentration of 8.75 gX.L-1, a volumetric biomass production rate of 0.295 g.L-1.h-1 and a volumetric glucose uptake rate of 0.293 g.L-1.h-1. Some feeding strategies were tested but further assays have to be performed in order to optimize the bioprocess.
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Krukenberg, Viola Verfasser], Gunter [Akademischer Betreuer] Wegener, Antje [Gutachter] [Boetius, and Ulrich [Gutachter] Fischer. "Physiological and genomic characterization of thermophilic methanotrophic archaea and their partner-bacteria / Viola Krukenberg. Betreuer: Gunter Wegener. Gutachter: Antje Boetius ; Ulrich Fischer." Bremen : Staats- und Universitätsbibliothek Bremen, 2015. http://d-nb.info/1103623257/34.
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Mupondi, Lushian Tapiwa. "Improving sanitization and fertiliser value of dairy manure and waste paper mixtures enriched with rock phosphate through combined thermophilic composting and vermicomposting." Thesis, University of Fort Hare, 2010. http://hdl.handle.net/10353/411.
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Thermophilic composting (TC) and vermicomposting (V) are the two most common methods used for biological stabilization of solid organic wastes. Both have their advantages and disadvantages but the proposed method of combining composting and vermicomposting (CV) borrows pertinent attributes from each of the two methods and combines them to enhance overall process and product qualities. Dairy manure and waste paper are two wastes produced in large quantities at the University of Fort Hare. The study was carried out to address the following specific objectives, to determine (i) the effectiveness of combined thermophilic composting and vermicomposting on the biodegradation and sanitization of mixtures of dairy manure and paper waste, (ii) an optimum precomposting period for dairy manure paper waste mixtures that results in vermicomposts of good nutritional quality and whose use will not jeopardize human health, (iii) the effectiveness of phosphate rock (PR) in increasing available P and degradation and nutrient content of dairy manure-paper vermicomposts, (iv) the physicochemical properties of vermicompost substituted pine bark compost and performance of resultant growing medium on plant growth and nutrient uptake. Results of this study revealed that wastes with a C: N ratio of 30 were more suitable for both V and CV as their composts were more stabilized and with higher nutrient contents than composts made from wastes with a C: N ratio of 45. Both V and CV were effective methods for the biodegradation of dairy manure and paper waste mixtures with C: N ratio of 30 but the latter was more effective in the biodegradation of waste mixtures with a C: N ratio of 45. The combinination of composting and vermicomposting eliminated the indicator pathogen E. coli 0157 from the final composts whereas V only managed to reduce the pathogen population. iv A follow up study was done to determine the effects of precomposting on pathogen numbers so as to come up with a suitable precomposting period to use when combine composting dairy manure-waste paper mixtures. Results of this study showed that over 95% of fecal coliforms, E. coli and of E. coli 0157 were eliminated from the wastes within one week of precomposting and total elimination of these and protozoan (oo)cysts achieved after 3 weeks of precomposting. The vermicomposts pathogen content was related to the waste’s precomposting period. Final vermicomposts pathogen content was reduced and varied according to precomposting period. Vermicomposts from wastes precomposted for over two weeks were less stabilized, less humified and had less nutrient contents compared to vermicomposts from wastes that were precomposted for one week or less. The findings suggest that a precomposting period of one week is ideal for the effective vermicomposting of dairy manure-waste paper mixtures. Results of the P enrichment study indicated an increase in the inorganic phosphate and a reduction in the organic phosphate fractions of dairy manure-waste paper vermicompost that were enriched with PR. This implied an increase in mineralization of organic matter and or solubilization of PR with vermicomposting time. Applying PR to dairy manure-waste paper mixtures also enhanced degradation and had increased N and P contents of dairy manure-waste paper vermicomposts. Earthworms accumulated heavy metals in their bodies and reduced heavy metal contents of vermicomposts. A study to determine the physicochemical properties of vermicompost substituted pine bark compost and performance of resultant growing medium on plant growth and nutrient uptake was done. Results obtained revealed that increasing proportions of dairy manure vermicomposts in pine bark compost improved tomato plant height, stem girth, shoot and root dry weights. v Tomatoes grew best in the 40 to 60% CV substituted pine bark and application of Horticote (7:2:1 (22)) fertilizer significantly increased plant growth in all media. Progressive substitution pine bark with dairy manure vermicomposts resulted in a decrease in the percentage total porosity, percentage air space whilst bulk density, water holding capacity, particle density, pH, electrical conductivity and N and P levels increased. Precomposting wastes not only reduced and or eliminated pathogens but also improved the stabilisation and nutrient content of dairy manure waste paper mixtures. The application of PR to dairy manure waste paper mixtures improved the chemical and physical properties of vermicomposts. Earthworms bio-accumulated the heavy metals Cd, Cr, Cu, Pb and Zn whilst the contents of these in the vermicomposts declined. It is, therefore, recommended that dairy manure waste paper mixtures be precomposted for one week for sanitization followed by PR application and vermicomposting for stabilization and improved nutrients contents of resultant vermicomposts. Substitution of pine bark compost with 40 to 60 % PR-enriched vermicompost produced a growing medium with superior physical and chemical properties which supported good seedling growth. However, for optimum seedling growth, supplementation with mineral fertilizer was found to be necessary.