dc.contributor.advisor | Daniel, Rolf PD Dr. | de |
dc.contributor.author | Özyurt, Baris | de |
dc.date.accessioned | 2012-05-16T12:10:36Z | de |
dc.date.available | 2013-01-30T23:51:06Z | de |
dc.date.issued | 2009-05-06 | de |
dc.identifier.uri | http://hdl.handle.net/11858/00-1735-0000-0006-B66A-8 | de |
dc.identifier.uri | http://dx.doi.org/10.53846/goediss-1359 | |
dc.description.abstract | Die dissimilatorische Fe(III)-Atmung ist eines der
frühesten Atmungssysteme und eventuell sogar die erste
anaerobe Atmung überhaupt. Mikroorganismen, die dieses
System beherbergen, verbinden die Elektronenübertragung
unterschiedlicher Elektronenspender auf den
Terminalelektronenakzeptor Fe(III) mit ihrem Wachstum.
Diese spezielle Atmung hat sowohl eine Funktion in den
Bioremediations- und Biokorrosionsprozessen als auch in
der Erzeugung von Elektrizität von bioorganischem
Material, was dessen großes Potential für zukünftige
Innovationen zeigt. Die Fe(III)-Atmung kommt in
phylogenetisch unterschiedlichen und in verschiedenen
marinen und terrestrischen Lebensräumen lebender
Prokaryonten vor. Bis jetzt konnten nur einige der
Elektrontransportproteine der Fe(III)-Atmung von
wenigen Mikroorganismen identifiziert werden. Die
Atmungsmodelle stammen aus Stämmen der Shewanella und
Geobacter. In dieser Studie wurden die Bestandteile der
dissimilatorischen Fe(IIII)-Atmung über die
kultivierungsabhängigen und phylogenetischen Grenzen
hinweg metagenomisch analysiert. Dazu wurden die aus
Boden- und Sedimentproben hergestellten Umweltgenbanken
mit Hilfe eines funktionsbasierten Screeningverfahrens
nach terminalen Fe(III)-Reduktasen durchmustert. Dabei
konnten ungefähr von 4 Millionen Klonen sechs
Positivklone mit einer dissimilatorischen
Fe(III)-Reduktase-Aktivität identifiziert werden. Die
Sequenzanalysen der geklonten metagenomischen
DNA-Fragmente ergaben eine Ähnlichkeit sowohl zu den
Actinobacteria, Firmicuten, als auch zu den α, β, und γ
Untergruppen der Proteobacteria. Die identifizierten
Genprodukte zeigten Ähnlichkeiten mit den
Oxydoreduktasen, Cytochrome C oder zu Proteinen, die
eine unbekannte Funktion beim Aufbau einer
dissimilatorischen Fe(III)-Atmung im Wirt haben. Ferner
wurden Fe(III)-Atmer aus Anreicherungskulturen mit
FePP-Minimalmedium isoliert und anschliessend
phylogenetisch und biochemisch charakterisiert. | de |
dc.format.mimetype | application/pdf | de |
dc.language.iso | ger | de |
dc.rights.uri | http://creativecommons.org/licenses/by-nd/2.0/de/ | de |
dc.title | Identifikation von Genen und Mikroorganismen, die an der dissimilatorischen Fe(III)-Reduktion beteiligt sind | de |
dc.type | doctoralThesis | de |
dc.title.translated | Isolation of Genes and Microorganisms Involved in Dissimilatory Fe(III)-Reduction | de |
dc.contributor.referee | Daniel, Rolf PD Dr. | de |
dc.date.examination | 2009-01-21 | de |
dc.subject.dnb | 500 Naturwissenschaften allgemein | de |
dc.description.abstracteng | Dissimilatory iron reduction is one of the earliest,
perhaps the first form of an anoxic respiratory system
on earth. Microorganisms harboring this system couple
their growth to the transfer of electrons from various
electron donors to the terminal electron acceptor
Fe(III) via terminal ferric iron reductases. Its
function in bioremediation and biocorrosion processes
and in the generation of electricity from bioorganic
material indicates a great potential for innovations in
the future.
This special form of metal respiration is distributed
among phylogenetically distinct prokaryotes living in
diverse marine and terrestrial habitats. Some proteins
taking part in the electron transport to the terminal
Fe(III) have already been identified and a few models
for dissimilatory Fe(III) reduction of Shewanella and
Geobacter species have been described. In this study,
the dissimilatory Fe(IIII) respiration was analyzed,
using a metagenomic approach that is independent of
cultivation. In order to assess the diversity of genes
encoding dissimilatory Fe(III) reductases, metagenomic
gene libraries were prepared from environmental DNAs
that have been isolated from grassland, river sediment,
thermal spring sediment or agricultural soil samples.
Subsequently, the constructed metagenomic libraries
were screened for the presence of genes encoding
dissimilatory Fe(III) reductases by a function-based
assay. The screening of approximately 4 million clones
resulted in the identification of six positive clones.
The recombinant plasmids recovered from these clones
enabled the Escherichia coli host to perform
dissimilatory Fe(III) reduction under anaerobic
conditions. Sequence analyses of the inserts of the
plasmids revealed a phylogenetic affiliation of the
cloned metagenomic DNA-fragments with Actinobacteria,
Firmicutes and the α, β, and γ subgroups of the
Proteobacteria. The products deduced from the
identified genes showed significant sequence
similarities to oxidoreductases, cytochrome C, and to
proteins whose involvement in electron transport
processes is unclear.
In addition, iron-reducing bacteria were isolated from
the studied environments via Iron-Minimal Media and
were pyhlogenetically and bio-chemically
characterised. | de |
dc.contributor.coReferee | Hoppert, Michael PD Dr. | de |
dc.subject.topic | Mathematics and Computer Science | de |
dc.subject.ger | Metagenomik | de |
dc.subject.ger | dissimilatorische Fe(III)-Reduktion | de |
dc.subject.eng | Dissimilatory iron reduction | de |
dc.subject.eng | DIR | de |
dc.subject.eng | dissimilatory oxido-reduction of iron | de |
dc.subject.eng | dissimilatory iron(III) reduction | de |
dc.subject.eng | metal reduction | de |
dc.subject.eng | ferricironreduction | de |
dc.subject.eng | microbial iron respiration | de |
dc.subject.eng | bacterial respiration | de |
dc.subject.eng | microorganisms for energy production | de |
dc.subject.eng | electron transfer;? electron transfer pathway | de |
dc.subject.eng | dissimilatory iron reducing bacteria | de |
dc.subject.eng | dissimilatory metal reducing bacteria | de |
dc.subject.eng | DMRB | de |
dc.subject.eng | energy production | de |
dc.subject.eng | electricity | de |
dc.subject.eng | energy transduction | de |
dc.subject.eng | microbial electricity | de |
dc.subject.eng | electron donor | de |
dc.subject.eng | electron acceptor | de |
dc.subject.eng | electron transfer | de |
dc.subject.eng | carbon source | de |
dc.subject.eng | carbohydrate | de |
dc.subject.eng | mannit | de |
dc.subject.eng | mannitol | de |
dc.subject.eng | biofilm | de |
dc.subject.eng | mineral | de |
dc.subject.eng | mineral formation | de |
dc.subject.eng | microbial degradation | de |
dc.subject.eng | ribosomal proteins | de |
dc.subject.eng | cytochromes | de |
dc.subject.eng | hypothetical proteins | de |
dc.subject.eng | enzymes | de |
dc.subject.eng | oxidation | de |
dc.subject.eng | reduction | de |
dc.subject.eng | ferric iron | de |
dc.subject.eng | iron oxide | de |
dc.subject.eng | Fe(II) | de |
dc.subject.eng | Fe(III) | de |
dc.subject.eng | soluble iron | de |
dc.subject.eng | insoluble iron | de |
dc.subject.eng | ferric reductase activity | de |
dc.subject.eng | iron mineral formation | de |
dc.subject.eng | mineralisation | de |
dc.subject.eng | <i>E. coli</i> | de |
dc.subject.eng | Escherichia coli | de |
dc.subject.eng | environmental microorganisms | de |
dc.subject.eng | life in extreme environments | de |
dc.subject.eng | uncultivable bacteria | de |
dc.subject.eng | microbial community;environmental samples | de |
dc.subject.eng | soil microbial ecology | de |
dc.subject.eng | anaerobic growth | de |
dc.subject.eng | anaerobic incubation | de |
dc.subject.eng | environmental sequences | de |
dc.subject.eng | environmental DNA | de |
dc.subject.eng | DNA extraction | de |
dc.subject.eng | functional screening | de |
dc.subject.eng | metagenomic | de |
dc.subject.eng | metagenome | de |
dc.subject.eng | meta-genome | de |
dc.subject.eng | microbial ecology | de |
dc.subject.eng | environmental genomics | de |
dc.subject.eng | soil metagenome | de |
dc.subject.eng | BACs | de |
dc.subject.eng | bacterial artificial chromosome libraries | de |
dc.subject.eng | sequencing | de |
dc.subject.eng | bioinformatics | de |
dc.subject.eng | microbial communities | de |
dc.subject.eng | 16S rRNA | de |
dc.subject.eng | phylogenetics | de |
dc.subject.bk | 30 | de |
dc.subject.bk | 42.30 | de |
dc.subject.bk | 42.30 | de |
dc.subject.bk | 58.30 | de |
dc.subject.bk | 42.49 | de |
dc.subject.bk | 58.30 | de |
dc.subject.bk | 42.13 | de |
dc.identifier.urn | urn:nbn:de:gbv:7-webdoc-2102-0 | de |
dc.identifier.purl | webdoc-2102 | de |
dc.affiliation.institute | Biologische Fakultät inkl. Psychologie | de |
dc.subject.gokfull | RA | de |
dc.subject.gokfull | W | de |
dc.identifier.ppn | 606110437 | de |