@article{AlbrechtSharmaReinhardtetal.2010,
  author    = {Albrecht, Marco and Sharma, Cynthia M. and Reinhardt, Richard and Vogel, Joerg and Rudel, Thomas},
  title     = {Deep sequencing-based discovery of the Chlamydia trachomatis transcriptome},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68389},
  year      = {2010},
  abstract  = {Chlamydia trachomatis is an obligate intracellular pathogenic bacterium that has been refractory to genetic manipulations. Although the genomes of several strains have been sequenced, very little information is available on the gene structure of these bacteria. We used deep sequencing to define the transcriptome of purified elementary bodies (EB) and reticulate bodies (RB) of C. trachomatis L2b, respectively. Using an RNAseq approach, we have mapped 363 transcriptional start sites (TSS) of annotated genes. Semiquantitative analysis of mapped cDNA reads revealed differences in the RNA levels of 84 genes isolated from EB and RB, respectively. We have identified and in part confirmed 42 genome- and 1 plasmid-derived novel non-coding RNAs. The genome encoded non-coding RNA, ctrR0332 was one of the most abundantly and differentially expressed RNA in EB and RB, implying an important role in the developmental cycle of C. trachomatis. The detailed map of TSS in a thus far unprecedented resolution as a complement to the genome sequence will help to understand the organization, control and function of genes of this important pathogen.},
  subject      = {Biologie},
  language  = {en}
}
@phdthesis{Arumugam2010,
  author    = {Arumugam, Manimozhiyan},
  title     = {Comparative metagenomic analysis of the human intestinal microbiota},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-55903},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2010},
  abstract  = {The human gut is home for thousands of microbes that are important for human life. As most of these cannot be cultivated, metagenomics is an important means to understand this important community. To perform comparative metagenomic analysis of the human gut microbiome, I have developed SMASH (Simple metagenomic analysis shell), a computational pipeline. SMASH can also be used to assemble and analyze single genomes, and has been successfully applied to the bacterium Mycoplasma pneumoniae and the fungus Chaetomium thermophilum. In the context of the MetaHIT (Metagenomics of the human intestinal tract) consortium our group is participating in, I used SMASH to validate the assembly and to estimate the assembly error rate of 576.7 Gb metagenome sequence obtained using Illumina Solexa technology from fecal DNA of 124 European individuals. I also estimated the completeness of the gene catalogue containing 3.3 million open reading frames obtained from these metagenomes. Finally, I used SMASH to analyze human gut metagenomes of 39 individuals from 6 countries encompassing a wide range of host properties such as age, body mass index and disease states. We find that the variation in the gut microbiome is not continuous but stratified into enterotypes. Enterotypes are complex host-microbial symbiotic states that are not explained by host properties, nutritional habits or possible technical biases. The concept of enterotypes might have far reaching implications, for example, to explain different responses to diet or drug intake. We also find several functional markers in the human gut microbiome that correlate with a number of host properties such as body mass index, highlighting the need for functional analysis and raising hopes for the application of microbial markers as diagnostic or even prognostic tools for microbiota-associated human disorders.},
  subject      = {Darmflora},
  language  = {en}
}
@phdthesis{Aso2010,
  author    = {Aso, Yoshinori},
  title     = {Dissecting the neuronal circuit for olfactory learning in Drosophila},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-55483},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2010},
  abstract  = {This thesis consists of three major chapters, each of which has been separately published or under the process for publication. The first chapter is about anatomical characterization of the mushroom body of adult Drosophila melanogaster. The mushroom body is the center for olfactory learning and many other functions in the insect brains. The functions of the mushroom body have been studied by utilizing the GAL4/UAS gene expression system. The present study characterized the expression patterns of the commonly used GAL4 drivers for the mushroom body intrinsic neurons, Kenyon cells. Thereby, we revealed the numerical composition of the different types of Kenyon cells and found one subtype of the Kenyon cells that have not been described. The second and third chapters together demonstrate that the multiple types of dopaminergic neurons mediate the aversive reinforcement signals to the mushroom body. They induce the parallel memory traces that constitute the different temporal domains of the aversive odor memory. In prior to these chapters, "General introduction and discussion" section reviews and discuss about the current understanding of neuronal circuit for olfactory learning in Drosophila.},
  subject      = {Taufliege},
  language  = {en}
}
@article{BollazziRoces2010,
  author    = {Bollazzi, Martin and Roces, Flavio},
  title     = {The thermoregulatory function of thatched nests in the South American grass-cutting ant, Acromyrmex heyeri},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68225},
  year      = {2010},
  abstract  = {The construction of mound-shaped nests by ants is considered as a behavioral adaptation to low environmental temperatures, i.e., colonies achieve higher and more stables temperatures than those of the environment. Besides the well-known nests of boreal Formica wood-ants, several species of South American leaf-cutting ants of the genus Acromyrmex construct thatched nests. Acromyrmex workers import plant fragments as building material, and arrange them so as to form a thatch covering a central chamber, where the fungus garden is located. Thus, the degree of thermoregulation attained by the fungus garden inside the thatched nest largely depends on how the thatch affects the thermal relations between the fungus and the environment. This work was aimed at studying the thermoregulatory function of the thatched nests built by the grass-cutting ant Acromyrmex heyeri Forel (Hymenoptera: Formicidae: Myrmicinae). Nest and environmental temperatures were measured as a function of solar radiation on the long-term. The thermal diffusivity of the nest thatch was measured and compared to that of the surrounding soil, in order to assess the influence of the building material on the nest's thermoregulatory ability. The results showed that the average core temperature of thatched nests was higher than that of the environment, but remained below values harmful for the fungus. This thermoregulation was brought about by the low thermal diffusivity of the nest thatch built by workers with plant fragments, instead of the readily-available soil particles that have a higher thermal diffusivity. The thatch prevented diurnal nest overheating by the incoming solar radiation, and avoided losses of the accumulated daily heat into the cold air during the night. The adaptive value of thatching behavior in Acromyrmex leaf-cutting ants occurring in the southernmost distribution range is discussed.},
  subject      = {Acromyrmex heyeri},
  language  = {en}
}
@phdthesis{Brandes2010,
  author    = {Brandes, Nicolas},
  title     = {Oxidative Thiol Modifications in Pro- and Eukaryotic Organisms},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-46542},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2010},
  abstract  = {Cystein spielt eine wichtige Rolle in der Biochemie vieler Proteine. Aufgrund der Redox-Eigenschaften und der hohen Reaktivit{\"a}t der freien Thiol-Gruppe sowie dessen F{\"a}higkeit Metallionen zu koordinieren, ist Cystein oft Bestandteil von katalytischen Zentren vieler Enzyme. Zudem lassen sich Cysteine durch reaktive Sauerstoff- und Stickstoffspezies leicht reversibel oxidativ modifizieren. In den letzten Jahren wurde gezeigt, dass Proteine redox-bedingte Thiol-Modifikationen nutzen, um Ver{\"a}nderungen ihrer Aktivit{\"a}t zu steuern. Diese redox-regulierten Proteine spielen eine zentrale Rolle in vielen physiologischen Prozessen. Das erste Ziel meiner Arbeit war die Identifizierung von Stickstoffmonoxid (NO)-sensitiven Proteinen in E. coli. Die redox-bedingten Funktions{\"a}nderungen solcher Proteine erkl{\"a}ren m{\"o}glicherweise die ver{\"a}nderte Physiologie von E. coli Zellen, die unter NO-Stress leiden. Um E. coli Proteine zu identifizieren, die unter Einwirkung von NO-Stress reversibel Thiol-modifiziert werden, wandte ich eine Kombination aus differentiellem Thiol-Trapping und 2D Gel-Elektrophorese an. Es wurden zehn Proteinen identifiziert, welche NO-sensitive Thiol-Gruppen enthalten. Genetische Studien ergaben, dass Modifikationen an AceF \& IlvC mitverantwortlich sind f{\"u}r die NO-induzierte Wachstumshemmung. Bemerkenswert ist es, dass die Mehrheit der identifizierten Proteine speziell nur gegen reaktive Stickstoffspezies empfindlich ist, welches an einem der identifizierten Stickstoffmonoxid-sensitiven Proteinen, der kleinen Untereinheit von Glutamate synthase, getestet wurde. In vivo und in vitro Aktivit{\"a}tsstudien zeigten, dass es zu einer schnellen Inaktivierung von Glutamate synthase nach NO-Behandlung kommt, das Protein aber resistent gegen{\"u}ber anderen Oxidationsmittel ist. Diese Resultate implizieren, dass reaktive Sauerstoff- und Stickstoffspezies unterschiedliche physiologische Vorg{\"a}nge in Bakterien beeinflussen. Das zweite Ziel meiner Arbeit war es, redox-sensitive Proteine in S. cerevisiae zu identifizieren und deren Redox-Zustand als in vivo Read-Out zu verwenden, um die Rolle von oxidativen Stress w{\"a}hrend des Alterungsprozess eukaryotischer Zellen zu analysieren. Zun{\"a}chst bestimmte ich in Hefezellen mit Hilfe von OxICAT, einer hochsensiblen quantitativen Methode, die Thiol-Trapping mit Massenspektrometrie verbindet, den exakten in vivo Thiol-Status von fast 300 Proteinen. Diese Proteine lassen sich in vier Gruppen einteilen: 1) Proteine, deren Cysteinreste resistent gegen Oxidation sind; 2) Proteine, in denen Cysteinmodifikationen strukturelle Aufgaben {\"u}bernehmen; 3) Proteine mit oxidationsempfindlichen Cysteinen, die bereits eine gewisse Oxidation in exponentiell wachsenden Hefezellen aufweisen; 4) Proteine, die reduziert sind, aber redox-sensitive Cysteinreste enthalten, die die Funktion der Proteine bei Vorhandensein von oxidativen Stress beeinflussen. Die Sensitivit{\"a}t dieser Proteine gegen{\"u}ber oxidativen Stress wurde durch Exposition subletaler Konzentrationen von H2O2 oder Superoxid auf Hefezellen nachgewiesen. Es wurde gezeigt, dass die wichtigsten zellul{\"a}ren Angriffspunkte von H2O2- und Superoxid-bedingtem Stress Proteine sind, die an Vorg{\"a}ngen der Translation, Glykolyse, des Citratzyklus und der Aminos{\"a}ure-Biosynthese beteiligt sind. Diese Zielproteine zeigen, dass Zellen f{\"u}r die Bek{\"a}mpfung von oxidativen Stress Metabolite schnell in Richtung des Pentosephosphatweges umleiten, um die Produktion des Reduktionsmittels NADPH sicherzustellen. Die hier pr{\"a}sentierten Ergebnisse belegen, dass die quantitative Bestimmung des Oxidationsstatus von Proteinen eine wertvolle Methode ist, um redox-sensitive Cysteinreste zu identifizieren. Die OxICAT Technologie wurde dann verwendet, um das genaue Ausmaß und die Entstehung von oxidativen Stress in chronologisch alternden S. cerevisiae Zellen zu bestimmen. F{\"u}r diese Bestimmung wurde der Oxidationsstatus von Proteinen in alternden Hefezellen als physiologischer Read-Out verwendet. Ich zeigte, dass die zellul{\"a}re Redox-Hom{\"o}ostase in chronologisch alternden Hefezellen global zusammenbricht, wobei es sich dabei um einen Prozess handelt, der dem Zelltod vorausgeht. Der Beginn dieses Zusammenbruchs scheint mit der Lebensdauer der Hefezellen zu korrelieren, da Kalorienrestriktion die Lebensdauer der Hefezellen erh{\"o}ht und den Zusammenbruch des Redox-Gleichgewichts verz{\"o}gert. Die Oxidation einer kleinen Anzahl an Proteinen (z.B. Thioredoxin reductase) geht dem Redox-Zusammenbruch deutlich voraus, was maßgeblich zum Verlust der Redox-Hom{\"o}ostase beitragen k{\"o}nnte. Diese Studien an alternden Hefezellen erweitern unser Verst{\"a}ndnis, wie sich Ver{\"a}nderungen in der Redox-Hom{\"o}ostase auf die Lebensdauer von Hefezellen auswirken. Zudem best{\"a}tigen die hier pr{\"a}sentierten Ergebnisse die Bedeutung von oxidativen Thiol-Modifikationen als eine der wichtigsten posttranslationalen Proteinmodifikationen in pro-und eukaryotischen Organismen},
  subject      = {Oxidativer Stress},
  language  = {en}
}
@phdthesis{Brandstaetter2010,
  author    = {Brandstaetter, Andreas Simon},
  title     = {Neuronal correlates of nestmate recognition in the carpenter ant, Camponotus floridanus},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-55963},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2010},
  abstract  = {Cooperation is beneficial for social groups and is exemplified in its most sophisticated form in social insects. In particular, eusocial Hymenoptera, like ants and honey bees, exhibit a level of cooperation only rarely matched by other animals. To assure effective defense of group members, foes need to be recognized reliably. Ants use low-volatile, colony-specific profiles of cuticular hydrocarbons (colony odor) to discriminate colony members (nestmates) from foreign workers (non-nestmates). For colony recognition, it is assumed that multi-component colony odors are compared to a neuronal template, located in a so far unidentified part of the nervous system, where a mismatch results in aggression. Alternatively, a sensory filter in the periphery of the nervous system has been suggested to act as a template, causing specific anosmia to nestmate colony odor due to sensory adaptation and effectively blocking perception of nestmates. Colony odors are not stable, but change over time due to environmental influences. To adjust for this, the recognition system has to be constantly updated (template reformation). In this thesis, I provide evidence that template reformation can be induced artificially, by modifying the sensory experience of carpenter ants (Camponotus floridanus; Chapter 1). The results of the experiments showed that template reformation is a relatively slow process taking several hours and this contradicts the adaptation-based sensory filter hypothesis. This finding is supported by first in-vivo measurements describing the neuronal processes underlying template reformation (Chapter 5). Neurophysiological measurements were impeded at the beginning of this study by the lack of adequate technical means to present colony odors. In a behavioral assay, I showed that tactile interaction is not necessary for colony recognition, although colony odors are of very low volatility (Chapter 2). I developed a novel stimulation technique (dummy-delivered stimulation) and tested its suitability for neurophysiological experiments (Chapter 3). My experiments showed that dummy-delivered stimulation is especially advantageous for presentation of low-volatile odors. Colony odor concentration in headspace was further increased by moderately heating the dummies, and this allowed me to measure neuronal correlates of colony odors in the peripheral and the central nervous system using electroantennography and calcium imaging, respectively (Chapter 4). Nestmate and non-nestmate colony odor elicited strong neuronal responses in olfactory receptor neurons of the antenna and in the functional units of the first olfactory neuropile of the ant brain, the glomeruli of the antennal lobe (AL). My results show that ants are not anosmic to nestmate colony odor and this clearly invalidates the previously suggested sensory filter hypothesis. Advanced two-photon microscopy allowed me to investigate the neuronal representation of colony odors in different neuroanatomical compartments of the AL (Chapter 5). Although neuronal activity was distributed inhomogeneously, I did not find exclusive representation restricted to a single AL compartment. This result indicates that information about colony odors is processed in parallel, using the computational power of the whole AL network. In the AL, the patterns of glomerular activity (spatial activity patterns) were variable, even in response to repeated stimulation with the same colony odor (Chapter 4\&5). This finding is surprising, as earlier studies indicated that spatial activity patterns in the AL reflect how an odor is perceived by an animal (odor quality). Under natural conditions, multi-component odors constitute varying and fluctuating stimuli, and most probably animals are generally faced with the problem that these elicit variable neuronal responses. Two-photon microscopy revealed that variability was higher in response to nestmate than to non-nestmate colony odor (Chapter 5), possibly reflecting plasticity of the AL network, which allows template reformation. Due to their high variability, spatial activity patterns in response to different colony odors were not sufficiently distinct to allow attribution of odor qualities like 'friend' or 'foe'. This finding challenges our current notion of how odor quality of complex, multi-component odors is coded. Additional neuronal parameters, e.g. precise timing of neuronal activity, are most likely necessary to allow discrimination. The lower variability of activity patterns elicited by non-nestmate compared to nestmate colony odor might facilitate recognition of non-nestmates at the next level of the olfactory pathway. My research efforts made the colony recognition system accessible for direct neurophysiological investigations. My results show that ants can perceive their own nestmates. The neuronal representation of colony odors is distributed across AL compartments, indicating parallel processing. Surprisingly, the spatial activity patterns in response to colony are highly variable, raising the question how odor quality is coded in this system. The experimental advance presented in this thesis will be useful to gain further insights into how social insects discriminate friends and foes. Furthermore, my work will be beneficial for the research field of insect olfaction as colony recognition in social insects is an excellent model system to study the coding of odor quality and long-term memory mechanisms underlying recognition of complex, multi-component odors.},
  subject      = {Neuroethologie},
  language  = {en}
}
@article{BrocherVogelHock2010,
  author    = {Brocher, Jan and Vogel, Benjamin and Hock, Robert},
  title     = {HMGA1 down-regulation is crucial for chromatin composition and a gene expression profile permitting myogenic differentiation},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-67914},
  year      = {2010},
  abstract  = {Background: High mobility group A (HMGA) proteins regulate gene transcription through architectural modulation of chromatin and the formation of multi-protein complexes on promoter/enhancer regions. Differential expression of HMGA variants has been found to be important for distinct differentiation processes and deregulated expression was linked to several disorders. Here we used mouse C2C12 myoblasts and C2C12 cells stably over-expressing HMGA1a-eGFP to study the impact of deregulated HMGA1 expression levels on cellular differentiation. Results: We found that induction of the myogenic or osteogenic program of C2C12 cells caused an immediate down-regulation of HMGA1. In contrast to wild type C2C12 cells, an engineered cell line with stable overexpression of HMGA1a-eGFP failed to differentiate into myotubes. Immunolocalization studies demonstrated that sustained HMGA1a-eGFP expression prevented myotube formation and chromatin reorganization that normally accompanies differentiation. Western Blot analyses showed that elevated HMGA1a-eGFP levels affected chromatin composition through either down-regulation of histone H1 or premature expression of MeCP2. RT-PCR analyses further revealed that sustained HMGA1a expression also affected myogenic gene expression and caused either down-regulation of genes such as MyoD, myogenin, Igf1, Igf2, Igfbp1-3 or up-regulation of the transcriptional repressor Msx1. Interestingly, siRNA experiments demonstrated that knock-down of HMGA1a was required and sufficient to reactivate the myogenic program in induced HMGA1a over-expressing cells. Conclusions: Our data demonstrate that HMGA1 down-regulation after induction is required to initiate the myogenic program in C2C12 cells. Sustained HMGA1a expression after induction prevents expression of key myogenic factors. This may be due to specific gene regulation and/or global effects on chromatin. Our data further corroborate that altered HMGA1 levels influence the expression of other chromatin proteins. Thus, HMGA1 is able to establish a specific chromatin composition. This work contributes to the understanding of how differential HMGA1 expression is involved in chromatin organization during cellular differentiation processes and it may help to comprehend effects of HMGA1 over-expression occurring in malign or benign tumours.},
  subject      = {HMG-Proteine},
  language  = {en}
}
@phdthesis{Derrer2010,
  author    = {Derrer, Bianca},
  title     = {Charakterisierung der Vitamin B6 Synthese und des Shikimatsyntheseweges im Malariaerreger Plasmodium ssp.},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-51456},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2010},
  abstract  = {Malaria ist eine schwerwiegende Krankheit, die j{\"a}hrlich {\"u}ber eine Million Menschen t{\"o}tet. Die zunehmende Resistenzbildung gegen{\"u}ber den verwendeten Medikamenten macht die Entwicklung neuer Antimalariamittel dringend notwendig. Daher sind die Vitamin B6 Synthese und der Shikimatweg von besonderem Interesse, da diese beiden Synthesewege nur im Parasiten und nicht im Menschen vorkommen. Unter der Voraussetzung, dass diese essentiell f{\"u}r den Parasiten sind, b{\"o}ten sie ideale Ansatzpunkte zur Entwicklung neuer Antimalariamittel. Voraus gegangene Studien haben gezeigt, dass Plasmodium falciparum in der Lage ist, PLP de novo mittels eines bifunktionalen Enzymkomplex, bestehend aus den Proteinen Pdx1 und Pdx2, zu synthetisieren. Pdx1 stellt dabei die eigentliche Synthase dar, w{\"a}hrend Pdx2 als Glutaminase-Partner das ben{\"o}tigte Ammoniumion f{\"u}r den heterocyclen Ring bereitstellt. Zus{\"a}tzlich dazu verf{\"u}gt der Parasit auch {\"u}ber einen salvage pathway um PLP zu „recyclen", in dem der Pyridoxalkinase PdxK eine Schl{\"u}sselfunktion zuf{\"a}llt. Knockout Studien der pdx1 im Mausmalariasystem P. berghei haben gezeigt, dass PbPdx1 f{\"u}r eine optimale Entwicklung der Blutstadien ben{\"o}tigt wird, nicht jedoch f{\"u}r deren {\"U}berleben. Im Rahmen dieser Arbeit habe ich die Effekte eines pbpdxK(-) Knockouts in demselben System untersucht. Es konnte eine monoklonale Knockoutlinie generiert werden, was zeigte, dass PbPdxK nicht essentiell f{\"u}r das {\"U}berleben des Parasiten in den Blutstadien ist. Die Entwicklung w{\"a}hrend des Blutstadiums war von dem pbpdxK(-) Knockout nicht betroffen. Allerdings zeigte sich im Moskitostadium eine drastische Reduktion der Sporozoitenzahl sowohl in den Mitteld{\"a}rmen als auch in den Speicheldr{\"u}sen. Dieses Ergebnis legt nahe, dass PbPdxK essentiell f{\"u}r das {\"U}berleben der Sporozoiten ist. Daneben wurde versucht, die Gene pfpdx1, pfpdx2 sowie pfpdxK in P. falciparum 3D7 durch Verwendung der single cross over Strategie auszuschalten. Es konnte jedoch f{\"u}r keines der genannten Konstrukte eine Integration in die jeweiligen Genloci anhand von PCR-Analysen nachgewiesen werden. Ebenso scheiterte der Versuch, durch Rekombination eines komplement{\"a}ren Genabschnitts die Funktion des Gens zu rekonstituieren. Daher bleibt es unklar, ob pfpdx1, pfpdx2 und pfpdxK durch Knockout Strategien auszuschalten sind oder nur f{\"u}r Genmanipulationen nicht zug{\"a}nglich sind. Die Kultivierung von P. falciparum 3D7 Parasiten in Vitamin B6 depletiertem Medium hatte keinen Effekt auf deren Wachstum. Eine anschließende Analyse der Proteinextrakte zeigte eine erh{\"o}hte Expression der PfPdxK, w{\"a}hrend sich das Expressionslevel der PfPdx1 nicht ver{\"a}nderte. Es scheint, dass der Parasit in der Lage ist Vitamin B6 Mangel durch vermehrte Nutzung des salvage pathways vollst{\"a}ndig zu kompensieren. Fr{\"u}here Arbeiten zeigten, dass der C-Terminus der Pdx1 in die Aktivit{\"a}t des PLP Synthasekomplexes involviert ist. Aus diesem Grund wurden verschiedene C-terminale Deletionsmutanten der PfPdx1 konstruiert und dabei bis zu 30 Aminos{\"a}uren entfernt. Diese Analysen ergaben, dass der C-Terminus vier verschiedene Funktionen besitzt: das Assembly der Pdx1 Untereinheiten zum Dodekamer, die Bindung des Pentosesubstrats Ribose 5-Phosphat, die Bildung des Intermediats I320 und schließlich die PLP Synthese. Diese unterschiedlichen Funktionen wurden durch verschiedene Deletionsvarianten identifiziert. Dar{\"u}ber hinaus waren alle Deletionsvarianten in der Lage, die Glutaminase Pdx2 zu aktivieren, was zeigt, dass das Dodekamer nicht Vorraussetzung f{\"u}r die Glutaminaseaktivit{\"a}t ist. Aufgrund der geringen PLP Syntheseaktivit{\"a}t in vitro wurde vermutet, dass der PfPdx1/PfPdx2 Komplex durch einen zus{\"a}tzlichen Faktor aktiviert wird. Daher wurde versucht, mittels Yeast 2-Hybrid, basierend auf einer PCR-amplifizierten P. falciparum 3D7 cDNA-Bibliothek als bait und PfPdx1 als prey, einen Interaktionspartner zu identifizieren. Mehrere Klone wurden gewonnen, die alle einen Bereich des Mal13P1.540, einem putativen Hsp70 Proteins, enthielten. Jedoch scheiterten alle Versuche, die Protein-Protein-Interaktion mit rekombinant exprimierten Protein zu best{\"a}tigen. Ebenso war es nicht m{\"o}glich, das vollst{\"a}ndige Mal13P1.540 rekombinant zu exprimieren sowie dessen Lokalisation in vivo zu bestimmen. Daher bleibt die Interaktion von PfPdx1 und Mal13P1.540 ungekl{\"a}rt. Neben der Vitamin B6 Biosynthese konnten auch einige Gene des Shikimatweges in Plasmodium identifiziert werden. In P. berghei konnten der C-terminale Teil der 3-Dehydroquinatsynthase (2) sowie die Shikimatkinase (5) und die 5-Enoylpyruvylshikimat 3-Phosphatsynthase (6) in einem open reading frame (ORF) identifiziert werden, der dieselbe genetische Organisation aufweisen wie der Arom-Komplex der Hefen. Mit Hilfe eines Komplementationsassay wurde die Funktionalit{\"a}t dieses ORFs {\"u}berpr{\"u}ft. Dazu wurden S. cerevisiae BY4741Δaro1, ein Hefestamm ohne funktionalen Arom-Komplex, mit dem Pb2_6_5_ABC Fragment transformiert. Die so transformierten Hefen waren nicht in der Lage, auf Mangelplatten ohne aromatische Aminos{\"a}uren zu wachsen, was zeigte, dass das Pb2_6_5_ABC Konstrukt den BY4741Δaro1 Ph{\"a}notyp nicht komplementieren konnte. Der Versuch, mit Hilfe des Baculovirussytems rekombiant exprimiertes Protein zu erhalten, verlief erfolglos. Ebenso war es nicht m{\"o}glich, Teile des Proteins f{\"u}r Immunisierungen zu exprimieren. Daher bleibt die Funktionalit{\"a}t des Pb2_6_5_ABC Konstruktes ungekl{\"a}rt.},
  subject      = {Plasmodium falciparum},
  language  = {de}
}
@phdthesis{Deuchert2010,
  author    = {Deuchert, Thomas},
  title     = {Entwicklung eines experimentellen Systems zur Untersuchung der subzellul{\"a}ren Lokalisierung der Alpha-Methylacyl-CoA-Racemase},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-46495},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2010},
  abstract  = {Entwicklung eines experimentellen Systems zur Untersuchung der subzellul{\"a}renLokalisierung der Alpha-Methylacyl-CoA-Racemase (AMACR) (Methode der retroviralen Transfektion von transformierten, embryonalen Mausfibroblasten)},
  subject      = {Alpha-Methylacyl-CoA-Racemase},
  language  = {de}
}
@article{DrescherBluethgenSchmittetal.2010,
  author    = {Drescher, Jochen and Bluethgen, Nico and Schmitt, Thomas and Buehler, Jana and Feldhaar, Heike},
  title     = {Societies Drifting Apart? Behavioural, Genetic and Chemical Differentiation between Supercolonies in the Yellow Crazy Ant Anoplolepis gracilipes},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-68573},
  year      = {2010},
  abstract  = {Background: In populations of most social insects, gene flow is maintained through mating between reproductive individuals from different colonies in periodic nuptial flights followed by dispersal of the fertilized foundresses. Some ant species, however, form large polygynous supercolonies, in which mating takes place within the maternal nest (intranidal mating) and fertilized queens disperse within or along the boundary of the supercolony, leading to supercolony growth (colony budding). As a consequence, gene flow is largely confined within supercolonies. Over time, such supercolonies may diverge genetically and, thus, also in recognition cues (cuticular hydrocarbons, CHC's) by a combination of genetic drift and accumulation of colony-specific, neutral mutations. Methodology/Principal Findings: We tested this hypothesis for six supercolonies of the invasive ant Anoplolepis gracilipes in north-east Borneo. Within supercolonies, workers from different nests tolerated each other, were closely related and showed highly similar CHC profiles. Between supercolonies, aggression ranged from tolerance to mortal encounters and was negatively correlated with relatedness and CHC profile similarity. Supercolonies were genetically and chemically distinct, with mutually aggressive supercolony pairs sharing only 33.1\%617.5\% (mean 6 SD) of their alleles across six microsatellite loci and 73.8\%611.6\% of the compounds in their CHC profile. Moreover, the proportion of alleles that differed between supercolony pairs was positively correlated to the proportion of qualitatively different CHC compounds. These qualitatively differing CHC compounds were found across various substance classes including alkanes, alkenes and mono-, di- and trimethyl-branched alkanes. Conclusions: We conclude that positive feedback between genetic, chemical and behavioural traits may further enhance supercolony differentiation through genetic drift and neutral evolution, and may drive colonies towards different evolutionary pathways, possibly including speciation.},
  subject      = {Ameisen},
  language  = {en}
}