Year: 2024, 2024
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The neuronal ceroid lipofuscinoses (NCLs), commonly known as Batten disease, are a family of fatal neurodegenerative disorders that primarily affect children. Several subtypes of NCLs have been reported, each being caused by a mutation in a distinct ceroid lipofuscinosis neuronal (CLN) gene; this results in aberrant lysosome function and the accumulation of lipoprotein aggregates (known… more
Year: 2024, 2024
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Giardia intestinalis is the causative agent of a diarrheal disease in mammals, but the mechanisms of disease pathogenesis are unclear. While proteins secreted by Giardia affect the host cells, the potential of hormone secretion has not been investigated to date. Cytokinins (CKs) are classified as phytohormones, but little is known about their role beyond plants. Mass spectrometry-based… more
Year: 2022, 2022
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Giardia intestinalis is a waterborne enteric parasite that lacks mitochondria and the capacity for heme biosynthesis. Despite this, Giardia encodes several heme proteins, including four cytochrome b5 isotypes (gCYTB5-I – IV) of unknown function. The aim of this thesis is to gain insight into the function of the Giardia cytochrome b5 isotype III (gCYTB5-III) that is found in the nucleus,… more
Year: 2022, 2022
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Amino acids make up proteins, which are the building blocks of life. A balance of amino acids is needed to maintain a healthy state. Tyrosine (Tyr) is synthesized from the metabolism of phenylalanine, which is an essential amino acid, meaning it can only be obtained from the diet. It is related to many metabolic and neurodegenerative diseases. Tyr can undergo post-translational… more
Year: 2020, 2020
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The waterborne protozoan Giardia intestinalis cycles between the environmentally-resistant and infectious cyst and the metabolically-active trophozoite that adheres to the epithelial lining of the small intestine. Adhesion can trigger the innate immune response in epithelial cells, including the synthesis of the free radical nitric oxide (NO) that inhibits cell proliferation and… more
Year: 2019, 2019
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Sajer, Bayan, Thesis advisor (ths): Yee, Janet, Degree committee member (dgc): Rafferty, Steven, Degree committee member (dgc): Bates, Holly, Degree committee member (dgc): Brunetti, Craig, Degree granting institution (dgg): Trent University Abstract: <p>The parasitic protist Giardia intestinalis has five heme proteins: a flavohemoglobin and several isotypes of cytochrome b5. While the flavohemoglobin has a role in counteracting nitric oxide, the functions of the cytochromes (gCYTb5s) are unknown. In this study, the protein level and cellular localization of three gCYTB5 isotypes (gCYTb5-I, II and III) and flavohemoglobin were examined… more
Year: 2018, 2018
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Ustilago maydis is a biotrophic fungal plant pathogen that causes 'common smut of corn' disease. During infection, U. maydis develops a metabolic dependency on its host, relying on uptake of the carbon molecules provided within Zea mays tissues. The research presented indicated a requirement for metabolism of the pentose sugar D-xylose through functional investigation of a U.… more
Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Paleczny, Andrea Rose, Thesis advisor (ths): Emery, Neil, Degree committee member (dgc): Yee, Janet, Degree committee member (dgc): Saville, Barry, Degree committee member (dgc): Olechowski, Henry, Degree granting institution (dgg): Trent University Abstract: <p>Cytokinins (CKs) are a family of plant phytohormones responsible for many areas of plant growth and development. There are four free base types of CKs found in higher plants, trans-zeatin (tZ), N6-(∆2-isopentenyl)adenine (iP), cis-Zeatin (cZ) and dihydrozeatin (DZ). CK biosynthesis is regulated by adenosine phosphate-isopentenyltransferase (IPT), which is encoded by a multi-gene family… more
Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The amitochondrial protozoan, Giardia intestinalis, encodes four members of the cytochrome b5 (CYTB5) family of heme proteins of unknown function. While homology models can predict the likely fold of these proteins, supporting experimental evidence is lacking. The small size of the cytochromes (~16 kDa) makes them attractive targets for structural analysis by Electron Paramagnetic… more
Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The parasitic protist Giardia intestinalis lacks most heme proteins yet encodes a flavohemoglobin (gFlHb) that converts nitric oxide to nitrate and likely protects the cell from nitrosative stress. In this work an antibody raised against gFlHb was used to examine both changes in gFlHb expression levels and intracellular localization in Giardia in response to nitrosative stress. Giardia… more
Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Abstract: <p>To study the Giardia intestinalis cell cycle, counterflow centrifugal elutriation (CCE) was used to separate an asynchronous trophozoite culture into fractions enriched for cells at the different stages of the cell cycle. For my first objective, I characterized the appearance of a third peak (Peak iii) in our flow cytometry analysis of the CCE fractions that initially suggested the… more
Year: 2017, 2017
Member of: Trent University Graduate Thesis Collection
Name(s): Creator (cre): Dayer, Guillem Sébastien, Thesis advisor (ths): Yee, Janet, Thesis advisor (ths): Rafferty, Steven, Degree committee member (dgc): Brunetti, Craig, Degree committee member (dgc): Saville, Barry, Degree granting institution (dgg): Trent University Abstract: <p>Giardia intestinalis is an anaerobic protozoan that lacks common eukaryotic heme-dependent respiratory complexes and does not encode any proteins involved in heme biosynthesis. Nevertheless, the parasite encodes several hemeproteins, including three members of the Type II cytochrome b5 sub-group of electron transport proteins found in anaerobic protist and amitochondriate organisms.… more
Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The flavohemoglobin in Giardia intestinalis (gFlHb) is the only known protozoan member of a protein class typically associated with detoxifying nitric oxide (by oxidation to nitrate) in bacteria and yeast. Mutants of the B10 tyrosine (Y30F) and E11 leucine (L58A), conserved residues thought to influence ligand binding, were expressed and studied using Resonance Raman (RR) spectroscopy.… more
Year: 2016, 2016
Member of: Trent University Graduate Thesis Collection
Abstract: <p>The aim of this work was to identify the DNA sequences recognized by the Giardia TBP (gTBP) in vivo by using a chromatin immunoprecipitation assay (ChIP). Since a specific antibody for the protein of interest is required for this assay, a company was contracted to produce and purify a custom polyclonal antibody from the immunization of rabbits. Recombinant GST-gTBP was produced at a… more
Year: 2015, 2015
Member of: Trent University Graduate Thesis Collection
Abstract: <p>Giardia lamblia is an intestinal parasite found globally in freshwater systems that is responsible for endemic outbreaks of infectious diarrhea. As a unicellular parasite that lacks mitochondria, a respiratory chain and lives in the anaerobic environment of its host's intestine, Giardia was assumed for decades to lack heme proteins. However, its genome encodes several putative heme… more
Year: 2014, 2014
Member of: Trent University Graduate Thesis Collection
Abstract: <p><italic>Ustilago maydis</italic> (DC) Corda is the causal agent of 'common smut of corn'. Completion of the <italic>U. maydis</italic> lifecycle is dependent on development inside its host, <italic>Zea mays</italic>. Symptoms of <italic>U. maydis</italic> infection include chlorosis and the formation of tumours on all aerial corn… more