- About
-
The Global ETD Search service is a free service for researchers
to find electronic theses and dissertations. This service is
provided by the
Networked Digital Library of Theses and Dissertations.
Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
Search results
Showing 1 to 8 of 8 (0.133 seconds)| 1 |
Functional analysis of STRIPAK complex components in the filamentous ascomycete Sordaria macrosporaReschka, Eva, Johanna 18 October 2017 (has links)
No description available.
|
| 2 |
Investigating the Roles of the Stk Locus in Development, Motility and Exopolysaccharide Production in Myxococcus XanthusLauer, Pamela L. M. 27 June 2007 (has links)
Myxococcus xanthus, a Gram-negative bacterium with a developmental cycle, displays a type IV pili (TFP) mediated surface motility known as social (S) gliding. Beside the polarly localized TFP, the fibril or extracellular polysaccharide (EPS) is also required for S-motility to function. It is proposed that S-motility, along with the related bacterial twitching motility in other species, is powered by TFP retraction. EPS is proposed to anchor and trigger such retractions in M. xanthus. EPS production is known to be regulated by TFP and the Dif signal transduction pathway. Two genetic screens were performed previously to identify additional genes important for EPS production. The first was for the isolation of pilA suppressors, the second for the identification of mutants underproducing EPS in a difA suppressor background. Both screens identified transposon insertions at the stk locus. In particular, StkA, a DnaK homolog, was identified as a possible negative regulator of EPS production by a stkA transposon insertion that suppressed a pilA mutation. A stkB transposon insertion was found to have diminished EPS production in a difA suppressor background.
In this study, in-frame deletion mutants of the five genes at the stk locus, stkY, stkZ, stkA, stkB and stkC, were constructed and examined. In addition, mutations of rbp and bskL, two genes downstream of the stk locus, were constructed. Like transposon insertions, the stkA in-frame deletion resulted in overproduction of EPS. The stkB and to a less extent the stkC mutants underproduced EPS. Mutations in the other genes had no obvious effects on EPS production. Genetic epistasis suggests that StkA functions downstream of TFP and upstream of the Dif sensory proteins in EPS regulation in M. xanthus. Epistasis analysis involving stkB was inconclusive. It is unresolved whether StkB plays a role in the biosynthesis or the regulation of EPS production in M. xanthus. / Master of Science
|
| 3 |
Regulation of Exopolysaccharide Production in Myxococcus XanthusBlack, Wesley P. 06 January 2006 (has links)
The surface gliding motility of Myxococcus xanthus is required for a multicellular developmental process initiated by unfavorable growth conditions. One form of the M. xanthus surface motility, social (S) gliding, is mediated by the extension and retraction of polarly localized type IV pili (Tfp). Besides Tfp, exopolysaccharides (EPS), another cell surface associated component, are also required for M. xanthus S motility. Previous studies demonstrated that the Dif chemotaxis-like signal transduction pathway is central to the regulation of EPS production in M. xanthus. Specifically, difA, difC and difE mutants were found to be defective in EPS production and S motility. DifA, DifC and DifE, homologous to methyl-accepting chemotaxis proteins (MCPs), CheW and CheA, respectively, are therefore positive regulators of EPS. This study, undertaken to better understand the regulation of EPS production, led to a few major findings. First, DifD and DifG, homologous to CheY and CheC, respectively, were found to be negative regulators of EPS production. Both DifD and DifG likely function upstream of the DifE kinase in EPS regulation. DifB, which has no homology to known chemotaxis proteins, was found not to be involved in EPS production. Secondly, this study led to the recognition that Tfp likely function upstream of the Dif pathway in the regulation of EPS production. Extracellular complementation experiments suggest that Tfp may act as sensors instead of signals for the Dif chemotaxis-like pathway. We propose a regulatory feedback loop that couples EPS production with Tfp function through the Dif signaling proteins. Lastly, we sought to identify additional genes involved in EPS production. Our efforts identified a mutation in a separate chemotaxis gene cluster as a suppressor of difA mutations, suggesting potential cross-talks among the multiple chemotaxis-like pathways in M. xanthus. In addition, we identified twenty-five previously uncharacterized genes that are predicted to be involved in M. xanthus EPS production. These genes appear to encode additional EPS regulators and proteins with biosynthetic function. / Ph. D.
|
| 4 |
Functional and structural analysis of carbonic anhydrases from the filamentous ascomycete Sordaria macrospora / Functional and structural analysis of carbonic anhydrases from the filamentous ascomycete Sordaria macrosporaLehneck, Ronny 09 April 2014 (has links)
No description available.
|
| 5 |
Extracellular matrix proteins in growth and fruiting body development of straw and wood degrading basidiomycetes / Extrazelluläre Matrix Proteine bei Wachstum und Fruchtkörperbildung in stroh- und holzabbauenden BasidiomyzetenVelagapudi, Rajesh 24 February 2006 (has links)
No description available.
|
| 6 |
Light effects on fruiting body development of wildtype in comparison to light-insensitive mutant strains of the basidiomycete Coprinopsis cinerea, grazing of mites (Tyrophagus putrescentiae) on the strains and production of volatile organic compounds during fruiting body developmentChaisaena, Wassana 17 July 2008 (has links)
No description available.
|
| 7 |
Untersuchung der Fruchtkörperentwicklung bei dem Hyphenpilz Sordaria macrospora / Analysis of fruiting-body development of the filamentous fungus Sordaria macrosporaBernhards, Yasmine 28 October 2010 (has links)
No description available.
|
| 8 |
Growth, fruiting body development and laccase production of selected coprini / Navarro González, MónicaNavarro González, Mónica 30 April 2008 (has links)
No description available.
|
Page generated in 0.143 seconds