Life Sciences Commons^™

Oligomerization Of Amyloid-Β Peptide In The Presence Of Gangliosides–Implications For Alzheimer Disease, Sydney Boyd

Honors Theses

Alzheimer disease (AD) is a neurodegenerative disorder that leads to memory impairment and cognitive dysfunction in elderly populations worldwide. A key characteristic of AD is the formation of neuritic plaques composed of extracellularly deposited aggregates of amyloid-β (Aβ), an intrinsically disordered protein. Although Aβ fibrils were once thought to be the prime initiators of the disease, research has since been shifted to consider soluble, low molecular weight Aβ oligomers as the driving force behind AD toxicity. Due to its origin as a cleavage product of amyloid precursor protein (APP), an integral membrane protein, Aβ is known to perpetually interact with …

Expression And Purification Of The Bacterial Protein Curli Csga And Its Cross-Interactions With Amyloid-B, Leah Grace Cantrell

Honors Theses

One of the main causes of neurodegenerative diseases is aggregation of amyloid proteins that are toxic to the neurons. Proteins like amyloid-β (Aβ) and α-syneuclein (α-syn) form hallmark aggregate lesions that contribute to pathological processes in the brain in Alzheimer and Parkinson’s patients, respectively. Recent ground-breaking studies have suggested a link between the microbiota of the gut and neurodegenerative diseases, called the “gut-brain axis.” It has been long known that the protein, CsgA found in many enteric bacteria, forms amyloid fibers of its own called Curli. Curli fibrils are a structural component of bacterial colonies and maintain the integrity of …

Cloning, Expression, And Purification Of Fadk And Its Application In Coa-Rna Capture, Jon-Michael L. Stork

Honors Theses

Coenzyme A (CoA) is an important enzyme cofactor involved in acyl transfer reactions. Recently, CoA and its various thioesters were found to exist at the 5’ end of RNA molecules. Although the function of these molecules is still unknown due to difficulties in their isolation, their existence at the 5’ RNA end reveals potentially novel biological roles of RNA. We are exploiting the broad substrate tolerance of the medium chain fatty acid-coenzyme A ligase (FadK), hypothesizing that this enzyme will accept biotinylated medium chain fatty acid substrates, creating biotin-tagged CoA-RNA. This modified CoA-RNA can later be captured using streptavidin affinity …

Elucidating The Interplay Between Sodium Selenite On The Tick Amblyomma Maculatum Selenoprotein Gene Expression, Afnan M. Beauti

Honors Theses

Selenium (Se) is an element recognized as an essential micronutrient in eukaryote organisms. Selenoproteins contain selenium as selenocysteine, the 21st amino acid. Selenium plays a role in cell growth and functioning. At low concentrations, it can induce growth and at high concentrations, it can cause a cell to stop growing and potentially have toxic effects on the cell and organism. When selenium levels are high, oxidative stress results by the production of reactive oxidative species. Selenoproteins, however, can aid the antioxidant response in the cell. Ticks are arthropods of interest, as they are one of few that contain many selenogenes, …

Altering The Structure Of Carboxysomal Carbonic Anhydrase Csosca To Determine The Necessity Of The N-Terminal Domain In Csosca Function, Dana L. Dillistone

Honors Theses

In this project, a DNA construct was designed and developed to remove the first fifty amino acids of the CsoSCA protein in the chemolithotrophic bacterium Halothiobacillus neapolitanus. The csoS3 gene codes for a carbonic anhydrase enzyme (CsoSCA) that is unique to a structure called a carboxysome. Carboxysomes are polyhedral microcompartments where carbon fixation is housed. The carbonic anhydrase is a shell-associated protein that improves the catalytic efficiency of ribulose-bisphosphate carboxylase/oxygenase (RuBisCO), the enzyme that catalyzes the fixation of carbon. By deleting the first fifty amino acids of the carbonic anhydrase, the necessity of the amino acids in carboxysome function was …

The Preparation Of Synthetic Myod Mrna For Cellular Differentiation And Innate Immune Response Downstream Application, James D. Grenn

Honors Theses

The development of therapeutic immune responses from the manipulation of embryonic stem cells (ESCs) via induction of synthetic RNA with 5’ capped and 3’ poly(A)tailed ends would lead to development of stem cell therapy. A necessary step in attaining such a goal is to first produce an mRNA transcript from a plasmid containing the open reading frame (ORF) for a transcription factor for cellular activation.

In this research, the DNA plasmid pMD4 encoding MyoD was transcribed into synthetic mRNA. The plasmid was first amplified using Polymerase Chain Reaction (PCR), and analyzed using gel electrophoresis. The amplified template was purified via …

Characterization Of P43lgrn-3, Kelly G. Hill

Honors Theses

Alzheimer’s Disease (AD) is a progressive neurodegenerative disorder characterized by extensive memory loss and cognitive deficits, which occur due to severe neuronal loss. Two hallmark lesions, intracellular neurofibrillary tangles composed of hyperphosphorylated tau and extracellular neuritic plaques formed by the aggregation of amyloid-β (Aβ), are responsible for the progressive neuronal loss seen in AD brains. Neurotoxic Aβ aggregates are also known to cause inflammation within the brain. It has recently come to light that severe and acute inflammation, such as seen in traumatic brain injury (TBI), may also lead to AD-type dementia. This has raised the question whether some of …

Developing A Deletion Construct Of The Halothiobacillus Neapolitanus Csos1c Gene, Ellyn K. Dunbar

Honors Theses

The purpose of this research was to develop a deletion construct for the chemoautotrophic bacterium Halothiobacillus neapolitanus, which will be used to generate a mutant lacking a carboxysome shell protein gene. The carboxysome is the location of carbon dioxide fixation. The operon that encodes the carboxysome contains three genes for CsoS1 proteins, the major components of the carboxysome shell. The small CsoS1 proteins self-assemble into hexamers with small central pores. The hexamers arrange into the facets of the icosahedral carboxysome shell. The pores are believed to be involved in selective diffusion of materials necessary for carbon dioxide fixation across the …

Granulins As Inflammatory Mediators In Alzheimer Disease, Randi G. Reed

Honors Theses

Alzheimer disease (AD) is a neurodegenerative disorder characterized by severe memory deficit and cognitive decline among the elderly. This degeneration is caused by the aggregation and deposition of a protein called amyloid-β (Aβ) in the brain. Aggregation of Aβ causes neuroinflammation in addition to other toxic events. However, it is unclear whether inflammation from an external source, such as from a traumatic brain injury (TBI), could trigger Aβ aggregation. In this context, several pro-inflammatory mediators such as cytokines and chemokines have been suspects. It is now hypothesized that a group of proteins called granulins (Grns) are unique inflammatory mediators that …

Cloning, Expression And Interaction Studies Of The Potential Rubisco Activase Cbbq, Salma A. Dawoud

Honors Theses

Carboxysomes are polyhedral microcompartments found in all cyanobacteria and in many chemoautotrophs. Within their shell they contain the enzyme ribulose-1, 5-bisphosphate carboxylase/oxygenase (RubisCO), which fixes CO₂. Downstream of the carboxysome operon there is another gene cluster containing several genes that may enhance carboxysome function. Two of these genes, cbbQ and cbbO, encode potential RubisCO activases. Using recombinant CbbQ and CbbO protein, and RubisCO isolated from carboxysomes the interaction between these proteins was studied. The CbbO and CbbQ proteins were both His tagged, allowing them to be purified with Ni²⁺-NTA column chromatography. Each of these tagged …