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GENOME SEQUENCE AND FUNCTIONAL COMPARISON OF THERMUS NMX2 A.1Tlalajoe, Nokuthula 21 August 2014 (has links)
The aim of this project was to sequence the whole genome of Thermus sp. NMX2 A.1 strain and compare it to the whole genome sequence of T. scotoductus SA-01.Therafter attempt to use experimental data to confirm functionality within the genomes and lastly isolate a new Thermus sp. from the fissure water samples routinely collected from the deep gold mines of South Africa and the Northam Platinum mine.
The genus Thermus has been extensively studied since the discovery of T. aquaticus in 1969 by Brock and Freeze and hundreds of species had been isolated ever since. However, up to date only eight validly described species are comprised in the genus Thermus.
Moreover, amongst this handful amount of species from the genus Thermus; great discoveries have been made and highlighted parts drew further attention in studying this genus even more. Their metabolism is one of the aspects looked into especially the denitrification respiration. With the application of a nitrate operon it is known that a few species within this genus are able to grow under such conditions, meanwhile; others are modified by genetically manipulating them to do so, for instance T. thermophilus HB27.
Subsequently, T. scotoductus SA-01 is reported to naturally possess the nitrate operon allowing it to grow in oxygen restricted conditions without any genetic manipulation applied. Recently, another strain was discovered to have the same functionalities as T. scotoductus SA-01 when grown under denitrification respiration with the supplement of potassium nitrate.
In addition to that, many phylogenetic similarities and identical remarks were also observed between T. scotoductus SA-01 and the newly sequence Thermus sp. NMX2 A.1 strain such as the ones carried out using the BOX-PCR fingerprinting. Comparison was, therefore, carried out on genome level to verify the phylogenetic similarities; of which was seen that the two strains shared up to (81.6%) similarities. The remaining percentage represented a set of genes that where uniquely found in the newly sequenced strain such entailed the Calvin cycle.
It is however, understandable as to why there might be differences between the two strains since the T. scotoductus SA-01 was isolated in the deep gold mines of South Africa and Thermus sp. NMX2 A.1 strain from the thermal hot springs of New Mexico in the USA. As a result; T. scotoductus SA-01 also indicated islands within its genome in which were not found in the newly sequenced strain.
A detailed experimental procedure was carried out to further support the theoretical similarities of the two strains with the presence of their genes that participate within the nitrate operon. Their functionalities were therefore analyzed using the profile of the nitrite detection as initial step of nitrate reduction, of which they showed an identical profile from the beginning of the incubation period until the end.
Lastly, with the advantages of a variety of fissure water samples collected from the different deep gold mines of South Africa and the Northam platinum mine a search for possible Thermus isolate was in addition performed. A range of different applications were implemented to obtain pure Gram negatives cells. This however, didnât successfully yield the expected results; even though there were numerous indications that the Gram negative cells where present and one could even hypothesize that those Gram negative cells were a genus Thermus since the ârotund bodiesâ characteristics were seen amongst these fissure water-samples. Unfortunately this directive was not achieved but the search continues to extend the known Thermus sp. isolations and exploration into their metabolic versatility.
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BIOLOGICAL REDUCTION OF SOLUBLE URANIUM BY AN INDIGENOUS BACTERIAL COMMUNITYMaleke, Maleke Mathews 21 August 2014 (has links)
Uranium (U) and chromium (Cr) in groundwater are a serious public health concern
due to their chemical toxicity. Even so, microorganisms have developed mechanisms which
permit them to thrive under previously perceived uninhabitable conditions. A number of
bacteria have been isolated from areas impacted with the soluble heavy metals, and can be
exploited as bioremediation agents since they are well adapted to these metals. To date, the
use of microbial mechanisms for bioremediation processes is a growing industry since it
provides green and sustainable technologies.
In this study, the upflow bioreactors were used as a low cost, low maintenance effective
bioremediation strategy in comparison to the available methods of remediation. Two metals
known to be toxic in their soluble state were treated. The first was Cr(VI) from an impacted
site in Limpopo and the second was U(VI) from the Wonderfonteinspruit catchment, North
West Province. The system was efficient for the removal of soluble Cr(VI) and U(VI) from
the impacted water through biostimulation of indigenous bacterial communities. This system
can be up scaled and employed for the remediation of impacted sites, and it will be useful
especially at low levels of U(VI). Indigenous bacterial community from impacted sites have
the capability to reduce Cr(VI) and U(VI) effectively over a sustainable period. The shortage
of electron donor and continuous oxygen exposure in the case of U(VI) act as a limiting
factor. However, in this study successful Cr(VI) and U(VI) reduction rates were increased by
the addition of an electron donor to stimulate the indigenous bacterial community.
Furthermore, a third upflow bioreactor showed that it is even possible with gradual
increases of U(VI) concentration that U(VI) bioreduction is possible at very high levels. The
influent water was spiked step wise with uranyl acetate, allowed to reach maximal U(VI)
reduction/removal and then the diversity was assessed. Despite the 10 mg/l U(VI) fed to the
bioreactor, the established microbial community was able to tolerate, adapt and thereby
remove the U(VI) from the spiked water. Even though biofilm could not sturdily adhere to
the matrix from the bioreactor, high levels of U(VI) removal could be achieved and the
planktonic community maintained. No biofilm could be observed from SEM analysis from
the TEM it was observed that the planktonic microbial community have an interaction with
uranium. Since no U(VI) could be detected from the effluent samples, it is thus postulated the
uranium in contact with the microbial cells is in another form, probably U(IV) as previously
shown in this laboratory. This study allows for the understanding of the metal microbe interactions in impacted environments, the use of this biome to remediate the water in an
effective, low cost and maintenance bioreactor.
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Steps toward optimization of ethanol production in the cyanobacterium Synechocystis PCC 6803Dexter, Jason P January 2007 (has links)
Thesis (M.S.)--University of Hawaii at Manoa, 2007. / Includes bibliographical references (leaves 66-68). / viii, 68 leaves, bound ill. 29 cm
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A Study of Biodiesel and its Properties from Two Feedstocks of Varied Iodine ValuesVora, VM Unknown Date (has links)
No description available.
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Harvesting biotechnology ventures : modeling the probabilities for alternative liquidity events /Amador, Carlos Mendiola. January 2008 (has links)
Thesis (Ph.D.)--University of Texas at Dallas, 2008. / Includes vita. Includes bibliographical references (leaves 232-241)
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Partitioning of biomolecules in thermo-separating polymer-water two-phase systemsJohansson, Hans-Olof. January 1996 (has links)
Thesis (doctoral)--University of Lund, 1996. / Added t.p. with thesis statement inserted.
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Partitioning of biomolecules in thermo-separating polymer-water two-phase systemsJohansson, Hans-Olof. January 1996 (has links)
Thesis (doctoral)--University of Lund, 1996. / Added t.p. with thesis statement inserted.
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Environmental biosafety of genetically engineered crops flax (Linum usitatissimum L.) as a model system /Jhala, Amitkumar Jayendrasinh. January 2010 (has links)
Thesis (Ph. D.)--University of Alberta, 2010. / Title from pdf file main screen (viewed on April 22, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Plant Science, Department of Agricultural, Food and Nutritional Science, University of Alberta. Includes bibliographical references.
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Biochemical characterization of 2,4,6-trichlorophenol degradation in bacterium Cupriavidus necator JMP134Belchik, Sara Mae. January 2009 (has links) (PDF)
Thesis (Ph. D.)--Washington State University, May 2009. / Title from PDF title page (viewed on June 4, 2009). "School of Molecular Biosciences." Includes bibliographical references.
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Mining a Chinese hyperthermophilic metagenome/Du Plessis, Morne Graham. Unknown Date (has links) (PDF)
Thesis (Ph. D) -- University of the Western Cape, 2007. / Includes bibliographic references , (186-222).
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