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The Investigation Of Microbe-Nematode Interactions, Chelsea K. Crepeau

Honors Theses and Capstones

No abstract provided.

Identification And Stoichiometric Analysis Of The Monosomal Translational Complex, Xin Wang

Doctoral Dissertations

The identification of the components involved in translational complexes has relied primarily on in vitro studies. Determining which proteins associate together in these complexes, under what conditions they do so, and how the composition of the complexes change under different conditions have became the key issues of in vivo studies. After a one-step affinity purification, using a novel technique of analytical ultracentrifugation with a fluorescence detection system (AU-FDS) I have identified a 77S monosomal translational complex in the yeast Saccharomyces cerevisiae. Major components of the 77S complex include the 80S ribosome, mRNA, and components of the closed-loop structure, eIF4E, eIF4G1/eIF4G2 …

Characterization Of The Expression Profile Of Polyamine Biosynthetic Genes (Spermidine Synthase) And Polyamine Metabolic Regulation In Arabidopsis, Lin Shao

Doctoral Dissertations

Polyamines are ubiquitously distributed cationic compounds, which play important roles in numerous cellular functions in plants. This study was aimed at elaborating the regulation of polyamine biosynthetic gene expression and polyamine metabolism. The organ/tissue specific expression patterns of two genes encoding the polyamine biosynthetic enzyme spermidine synthase ( AtSPDS1 and AtSPDS2) were studied in Arabidopsis at different developmental stages using promoter::reporter approach. The two homologues showed similar ubiquitous expression with subtle differences being observed in certain tissues (e.g. root, siliques, and embryos). Neither transgenic manipulation by over-expression of AtSPDSI alone nor its concomitant expression with genes encoding other biosynthetic enzymes …

Engineering Lipases And Solvents For Trans/-Esterification Of Used Vegetable Oils, Michael Dore Gagnon

Doctoral Dissertations

Diminishing petroleum reserves and increasing environmental awareness has led to an urgent need to develop alternative fuels, such as biodiesel. However, the conventional method to produce biodiesel uses environmentally harmful chemical catalysts. A relatively new development in the production of biodiesel is through enzymatic trans/- esterification with a lipase catalyst. Despite several advantages, there are a few technical and economical obstacles that limit this process: (1) immiscibility of the hydrophilic methanol and hydrophobic triglyceride which results in the formation of an interface leading to mass transfer resistance, (2) insufficient availability of large quantities of inexpensive lipase suitable for catalysis, and …

Patterns Of Cytosine Methylation In The Genome Of Caenorhabditis Elegans, Kazufusa Okamoto

Doctoral Dissertations

Recent large-scale comparative analysis of cytosine DNA methylation across diverse eukaryotes suggest that early features of DNA methylation present in the last common ancestor of all eukaryotes some 1.6 to 1.8 billion years ago included the methylation of gene bodies and transposable elements (Zemach, McDaniel et al. 2010; Parfrey, Lahr et al. 2011). These potentially ancient patterns may reflect a primitive role of methylation in transcriptional fidelity and as a mechanism to protect the germ line from transposon, or repeat, mediated mutation. Because spurious transcription and mutation are hypothesized to be among the critical limiting factors to genome size, an …

Viability Of Butternut (Juglans Cinerea L) In The Northeastern United States: An Assessment Of The Genetic Diversity, Health, And Hybridization And Recruitment Of Butternut In The Northeast, Andre A W Boraks

Master's Theses and Capstones

Butternut (Juglans cinerea) trees are being extirpated from their natural range by means of an epidemic caused by a fungal pathogen. Widespread mortality is reminiscent of past epidemics on American chestnut (Castanea dentata) and American elm (Ulmus americana ). Understanding the course of contemporary decline of this tree species will provide greater insight on processes of potential extinction and the results of management to prevent it.

This thesis applies an interdisciplinary approach to characterize butternut of the northeastern Unites States. While there is evidence of weak genetic structuring, butternut appears to have maintained sufficient dispersal to prevent isolation and inbreeding …

Patterns Of Intron Loss And Gain In Caenorhabditis, Gabrielle Giese

Master's Theses and Capstones

Introns, segments of genes that get spliced from the transcript before translation, are prevalent parts of many genomes and yet remain largely mysterious. Although their presence in the genome has been known for over thirty years, we still cannot answer the most fundamental questions about introns, such as where did they originate and, how are they gained and lost? In our most stringent dataset, we compared 137,453 intron positions in 6,257 pan-orthologs among four species of Caenorhabditis using a bioinformatics approach. While 82% of intron positions were conserved, we found a remarkable amount of intron variation. We also found evidence …