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Full-Text Articles in Life Sciences

Do Changes In Muscle Architecture Effect Post- Activation Potentiation, Danielle Reardon Jan 2013

Do Changes In Muscle Architecture Effect Post- Activation Potentiation, Danielle Reardon

Electronic Theses and Dissertations

Purpose: To examine the effect of three muscle potentiation protocols on changes in muscle architecture and the subsequent effect on jump power performance. Methods: Maximal (1RM) squat strength (Mean SD=178.3 ± 36.6kg), vertical jump power, and muscle architecture were obtained in 12 resistance trained men (25.2±3.6y; 90.67±12.7kg). Participants randomly completed three squatting protocols at 75% (3 x 10 reps), 90% (3 x 3 reps) or 100% (1 x 1) of their 1RM, or no workout (CON), with each protocol being separated by one week. During each testing session ultrasound and vertical jump testing were assessed at baseline (BL), 8min post …


Biogeography And Systematics Of The Nerodia Clarkii/Nerodia Fasciata Clade In Florida, Gregory Territo Jan 2013

Biogeography And Systematics Of The Nerodia Clarkii/Nerodia Fasciata Clade In Florida, Gregory Territo

Electronic Theses and Dissertations

Biogeography provides a window into the evolutionary history of populations, and helps explain the diversity and distribution of life through time. Viewed from a systematic perspective, biogeographic studies generate convincing arguments to explain the relationships among organisms and categorize them into useful taxonomies. When taxonomies do not reflect evolutionary histories, inaccurate representations of biodiversity confound future studies and conservation efforts. Two thamnophiine snakes, Nerodia clarkii and Nerodia fasciata, harbor unique morphological and ecological adaptations that obscured natural groupings, leading to controversial taxonomic delimitations. Additionally, population declines documented in N. clarkii compressicauda and N. clarkii taeniata led managers to list N. …


Estimated Diets, Diet Overlap, And Winter Habitat Associations Of Four Grassland Sparrows In Florida Dry Prairie, Marianne Korosy Jan 2013

Estimated Diets, Diet Overlap, And Winter Habitat Associations Of Four Grassland Sparrows In Florida Dry Prairie, Marianne Korosy

Electronic Theses and Dissertations

North American grassland birds show long-term population declines that generally exceed the declines of other bird groups. Efforts to conserve grassland birds require knowledge of diet and habitat requirements during both the breeding and nonbreeding periods of annual life cycles. This dissertation investigated sparrow habitat associations within two defined plant communities of the dry prairie ecosystem, the dry-mesic and wet-mesic prairie, for four prescribed fire treatments over two consecutive winters. Grasshopper and Henslow’s sparrows showed higher relative abundance in wet-mesic prairie and Bachman’s Sparrows were more abundant in dry-mesic prairie across all fire treatments. Abundances of Grasshopper and Bachman’s sparrows …


The Role Of Mitochondrial Omi/Htra2 Protease In Protein Quality Control And Mitophagy, Camilla Ambivero Jan 2013

The Role Of Mitochondrial Omi/Htra2 Protease In Protein Quality Control And Mitophagy, Camilla Ambivero

Electronic Theses and Dissertations

Omi/HtrA2 is a mitochondrial serine protease with a dual and opposite function depending on its subcellular localization. Most of the previous studies focused on Omi/HtrA2’s pro-apoptotic function when the protein is released to the cytoplasm. It is becoming apparent that the main function of Omi/HtrA2 is within the mitochondria, where it has a pro-survival role. However, its mechanism is still poorly understood. To this end, we used the yeast two-hybrid system to dissect the Omi/HtrA2 pathway by identifying novel interactors and substrates. Our studies revealed a novel function of Omi/HtrA2 in the regulation of a deubiquitinating (DUB) complex. In addition …


The Cytopathic Activity Of Cholera Toxin Requires A Threshold Quantity Of Cytosolic Toxin., Carly Bader Jan 2013

The Cytopathic Activity Of Cholera Toxin Requires A Threshold Quantity Of Cytosolic Toxin., Carly Bader

Electronic Theses and Dissertations

Cholera toxin (CT), secreted from Vibrio cholerae, causes a massive fluid and electrolyte efflux in the small intestine that results in life-threatening diarrhea and dehydration which impacts 3-5 million people per year. CT is secreted into the intestinal lumen but acts within the cytosol of intestinal epithelial cells. CT is an AB5 toxin that has a catalytic A1 subunit and a cell binding B subunit. CT moves from the cell surface to the endoplasmic reticulum (ER) by retrograde transport. Much of the toxin is transported to the lysosomes for degradation, but a secondary pool of toxin is diverted to the …


Characterization Of Motility Alterations Caused By The Impairment Of Dynein/Dynactin Motor Protein Complex, Swaran Nandini Jan 2013

Characterization Of Motility Alterations Caused By The Impairment Of Dynein/Dynactin Motor Protein Complex, Swaran Nandini

Electronic Theses and Dissertations

Transport of intracellular cargo is an important and dynamic process required for cell maintenance and survival. Dynein is the motor protein that carries organelles and vesicles from the cell periphery to the cell center along the microtubule network. Dynactin is a protein that activates dynein for this transport process. Together, dynein and dynactin forms a motor protein complex that is essential for transport processes in all the vertebrate cells. Using fluorescent microscope based live cell imaging techniques and kymograph analyses, I studied dynein/dynactin disruptions on the intracellular transport in two different cell systems. In one set of experiments, effects of …


Bone Morphogenetic Protein-7 (Bmp-7) Polarizes Monocytes Into M2 Macrophages, Crystal Rocher Jan 2013

Bone Morphogenetic Protein-7 (Bmp-7) Polarizes Monocytes Into M2 Macrophages, Crystal Rocher

Electronic Theses and Dissertations

Atherosclerosis is an inflammatory disease in which an accumulation of fatty acids and cholesterol occurs to form a plaque in small and large arteries. Monocyte polarization to classic M1 macrophages or alternative M2 macrophages is an important area of research that can determine the severity of disease progression. BMP-7 is a key growth factor responsible for directing differentiation of mesenchymal stem cells into brown fat cells, suggesting a role of BMP-7 in cellular plasticity; however, its role in monocyte polarization is yet to be revealed. In the current study, we hypothesize that monocyte treatment with BMP-7 will significantly result in …


Delineating Key Genetic Components On Linear Plasmid 36 That Contribute To Its Essential Role In Borrelia Burgdorferi Mammalian Infectivity., Tisha Choudhury Jan 2013

Delineating Key Genetic Components On Linear Plasmid 36 That Contribute To Its Essential Role In Borrelia Burgdorferi Mammalian Infectivity., Tisha Choudhury

Electronic Theses and Dissertations

The spirochete Borrelia burgdorferi is the etiologic agent of Lyme disease. This pathogen has a complex enzootic life cycle that involves passage between the tick vector (Ixodes scapularis) and various vertebrate hosts with humans being inadvertent hosts. There is a pressing need to study the genetic aspects of the B. burgdorferi infectious cycle and particularly spirochete genes involved in mammalian infectivity so as to develop novel therapeutic and diagnostic strategies to combat Lyme disease. The B. burgdorferi genome is fragmented and comprised of a single 900 kb linear chromosome and multiple linear and circular plasmids. It has been observed that …


Mixed Valence Copper(Cu)/Silica Nanocomposite: Synthesis, Characterization And Systematic Antimicrobial Studies, Mikaeel Young Jan 2013

Mixed Valence Copper(Cu)/Silica Nanocomposite: Synthesis, Characterization And Systematic Antimicrobial Studies, Mikaeel Young

Electronic Theses and Dissertations

Copper (Cu) compounds are widely used as effective agricultural bactericides. Continuous use of these materials has led to Cu accumulation in soil over time. The United States Environmental Protection Agency (US EPA) is concerned about potential Cu contamination in the environment. Improving biocidal efficacy of Cu is an attractive alternative, allowing reduction of Cu amount per application. In this research, we focused on making watersoluble mixed-valence Copper/Silica composite nanogel (CuSiNG) material. The objective is to improve the efficacy of Cu by manipulating Cu valence states. It has been shown in the literature that Cu (0) and Cu (I) states are …


Immuno-Pcr Detection Of Lyme Borreliosis, Micah Halpern Jan 2013

Immuno-Pcr Detection Of Lyme Borreliosis, Micah Halpern

Electronic Theses and Dissertations

Lyme borreliosis, more commonly referred to as Lyme disease, is the fastest growing zoonotic disease in North America with approximately 30,000 confirmed cases and 300,000 estimated infections per year. In nature, the causative agent of Lyme disease, the bacterium Borrelia burgdorferi, cycles between Ixodes sp. ticks and small mammals. Humans become infected with Lyme disease after being bitten by an infected tick. The primary indicator of a Borrelia burgdorferi infection is a bull’s eye rash typically followed by flu-like symptoms with treatment consisting of a 2-4 week course of antibiotics. If not treated, later stages of the disease can result …


Effects Of Dissolved Nutrient Ratios And Concentrations On Litter-Associated Microbial Activity In Streamside Channels, Timothy Burns Jan 2013

Effects Of Dissolved Nutrient Ratios And Concentrations On Litter-Associated Microbial Activity In Streamside Channels, Timothy Burns

Electronic Theses and Dissertations

Heterotrophic consumers, such as microorganisms and invertebrates, play a fundamental role in the flow of carbon and energy in streams. The effects of dissolved nutrient concentrations, and especially ratios, on litter—associated microorganisms and decomposition rates of detritus are poorly understood. This study addressed the responses of heterotrophic microbes to a wide range of concentrations and ratios of dissolved inorganic nitrogen (N) and phosphorus (P) in streamside channels simulating headwater streams. Two main questions were: (1) do microbial parameters and litter decomposition rates peak at a dissolved N:P ratio that approaches the nutrient ratio of microbial biomass, and (2) does microbial …


Historical Catch Trends And Efficacy Of Video Surveillance Monitoring Of Catch Per Unit Effort At Recreational Fishing Piers In South Carolina, Charles Christian Johnson Jan 2013

Historical Catch Trends And Efficacy Of Video Surveillance Monitoring Of Catch Per Unit Effort At Recreational Fishing Piers In South Carolina, Charles Christian Johnson

Electronic Theses and Dissertations

In recent years, recreational anglers claim declining catch rates in the shore-based pier fishery in South Carolina. The study seeks to evaluate whether catch data supports angler testimony in this region, to examine the relationship of landings at piers in context of the regional level, and to test a method which would enhance the ability of managers to monitor landings of this under-studied fishery. Novel, non-standardized catch series extending back to 1973 were acquired from fishing piers and examined in an attempt to produce significant trends in measures of catch. King mackerel catch (Scomberomorus cavalla) was tested for correlation to …


Impact Of Macroconsumers On Leaf Breakdown And Detritivores In Wet And Dry Wetlands On A Southeastern Us Coastal Plain Floodplain, Bryanna Libby Jan 2013

Impact Of Macroconsumers On Leaf Breakdown And Detritivores In Wet And Dry Wetlands On A Southeastern Us Coastal Plain Floodplain, Bryanna Libby

Electronic Theses and Dissertations

Interactions among macroconsumers (predators and large omnivores) and detritus breakdown are poorly understood on river floodplains. I evaluated the impact of macroconsumers on leaf breakdown, macroinvertebrate abundance and biomass, and fungal biomass on the Great Pee Dee River floodplain using exclosures in 6 wetlands. Sweetgum (Liquidambar styraciflua) leaves were held in mesh bags and in leaf packs. After 301 days, breakdown rates (k) were low in all treatments (k < 0.003 day-1) and did not significantly differ. Fungal biomass also did not significantly differ between treatments nor did overall macroinvertebrate abundance or biomass. Collector-gatherer invertebrates were significantly more abundant in treatments open to macroconsumers in mesh bags (P<0.001). Shredders had significantly higher biomass in packs held in exclosures closed to macroconsumers (P=0.048). Lack of rain limited stream-floodplain connectivity so a second, shorter study was done in one flooded wetland. After 98 days, pre-conditioned leaves in mesh bags open to macroconsumers had significantly higher breakdown rates (k = 0.0078 day-1) than those closed to macroconsumers (k = 0.0058 day-1; P= 0.050). Fungal biomass did not significantly differ between treatments. Total macroinvertebrate abundance (but not biomass) was higher in mesh bags open to macroconsumers (P=0.014). Scrapers and predators were significantly more abundant in mesh bags opens to macroconsumers (P=0.001 and P=0.004, respectively) than those closed to macroconsumers. These results indicated macroconsumers had a larger impact on litter breakdown in wet floodplain wetlands than in dry ones.


Differences In Habitat At Two Spatial Scales Fail To Predict Differing Occurrences Of Three Species Of Wintering Ammodramus Sparrows In South Carolina Salt Marshes, Kimberly A. Trinkle Jan 2013

Differences In Habitat At Two Spatial Scales Fail To Predict Differing Occurrences Of Three Species Of Wintering Ammodramus Sparrows In South Carolina Salt Marshes, Kimberly A. Trinkle

Electronic Theses and Dissertations

Salt marshes have low levels of vertebrate diversity yet extremely high rates of endemism. Two of these endemic species are the Saltmarsh (Ammodramus caudacutus) and Seaside Sparrow (A. maritima); the closely related Nelson's sparrow (A. nelsoni) winters exclusively on salt marshes. A previous winter study found that individual sparrows of all three species were highly faithful to specific banding sites, and that the relative abundances of the three species differed by site. I hypothesized that the reason sparrow assemblages varied among sites was that the three species' winter habitat requirements were different. All three species winter in salt marshes, but …


The Effects Of Intracerebroventricular Leptin On Milk Availability In Lactating Rats, Brittany Lynita Moore Dec 2012

The Effects Of Intracerebroventricular Leptin On Milk Availability In Lactating Rats, Brittany Lynita Moore

Electronic Theses and Dissertations

Reports have linked energy balance along with adipocyte derived leptin action to improved fertility. Recent evidence indicates that leptin hormone is present in breast milk and leptin receptors are well expressed in mammary epithelial cells. The hypothesis that insufficiency of leptin restraint in the hypothalamus may underlie infertility in rodents and the failure of lactating breast to express adequate amount of milk was tested. Female Sprague-Dawley rats were injected leptin through intracerebroventricular cannulation (ICVC) of the third ventricle. Female rats were mated with stud males and observed throughout gestation. Compared to the control groups, leptin treatment increased prolactin levels in …


Distribution And Social Structure Of An Estuarine Bottlenose Dolphin (Tursiops Truncatus) Population In Northern South Carolina, Jamie L. Brusa Dec 2012

Distribution And Social Structure Of An Estuarine Bottlenose Dolphin (Tursiops Truncatus) Population In Northern South Carolina, Jamie L. Brusa

Electronic Theses and Dissertations

Information regarding habitat preference of apex predators may pinpoint areas dense in resources such as prey species. Knowledge of how animals use their habitat can enable the classification and targeted management of important habitat features. This study was conducted to determine the distribution and social structure of an inshore population of bottlenose dolphins within the North Inlet-Winyah Bay estuary in northern South Carolina. Photo-identification surveys were conducted along defined transect routes. Home ranges of individual dolphins were calculated using the minimum convex polygon method and the fixed kernel density method using Geographic Information System (GIS) software. Mean group sizes and …


Assessment Of Land Use And Neotropical Herpetofauna Along Steep Gradients Of Elevation In An Ecuadorian Ramsar Wetland Site #1143, Nicholas K. Henke Dec 2012

Assessment Of Land Use And Neotropical Herpetofauna Along Steep Gradients Of Elevation In An Ecuadorian Ramsar Wetland Site #1143, Nicholas K. Henke

Electronic Theses and Dissertations

Using a comparative ecological approach, over the course of 18 days at the transition from a particularly wet to dry season in 2010, I assessed herpetofaunal assemblages and related abiotic parameters (i.e., photosynthetically active radiation, specific conductance, temperature and coarse woody debris) between contiguous forest and human impacted areas along three paired transects across the steep elevation gradient at Laguna de Cube, Ramsar site # 1143. Visual encounter surveys were used to capture herpetofauna with species being processed (e.g., weight, digit length, photographed) and identified to the lowest taxonomic level possible. After evaluating transect data for pooling (i.e., no significant …


Winter Site Fidelity In Secretive Marsh Sparrows Along The Coast Of South Carolina, Susan M. Shaw Dec 2012

Winter Site Fidelity In Secretive Marsh Sparrows Along The Coast Of South Carolina, Susan M. Shaw

Electronic Theses and Dissertations

Salt marshes, which are threatened by sea level rise and development, provide habitat for a distinctive suite of specialized vertebrates, and knowledge of the life histories of salt marsh specialists may help preserve salt marsh fauna in the face of change. I studied wintering site fidelity of Seaside (Ammodramus maritimus), Saltmarsh (A. caudacutus) and Nelson's (A. nelsoni) Sparrows by mist-netting and banding birds at six sites in two salt marshes in South Carolina. I banded 261 sparrows over two winters, 2009-2010 and 2010-2011, and recaptured 92. Across-year return rates were high, but significantly different across species: 43% for Seaside, 63% …


Characterization Of Fhua 104/149c: A Double Cysteine Fhua Mutant With Normal Binding And Diminished Transport, Ada K. Hagan Dec 2012

Characterization Of Fhua 104/149c: A Double Cysteine Fhua Mutant With Normal Binding And Diminished Transport, Ada K. Hagan

Electronic Theses and Dissertations

Iron is an essential element for most bacteria and is commonly acquired by siderophores, molecules secreted under iron restricted environment to bind ferric iron. Gram negative cells actively uptake these complexes via outer membrane-transport proteins such as FhuA in Escherichia coli. Structural analysis of receptors revealed a conserved β-barrel occluded by an N-terminal plug domain. The cell membrane TonB/ExbB/ExbD complex presumably supplies energy via interaction between the FhuA N-terminal TonB box and the C-terminal domain of TonB. In order to better understand the mechanism of action the FhuA mutant 104/149C, tethering the central β-strands 4 and 6 of the …


Biogenic Amine Levels Correlate With Time Of Day, Age, Light Cycle, And Aggressive State In The Flesh Fly, Sarcophaga Crassipalpis, Veronica L. Fregoso Dec 2012

Biogenic Amine Levels Correlate With Time Of Day, Age, Light Cycle, And Aggressive State In The Flesh Fly, Sarcophaga Crassipalpis, Veronica L. Fregoso

Electronic Theses and Dissertations

The biogenic amines serotonin (5HT), dopamine (DA), and octopamine (OA) have been indicated in the regulation of behaviors, including aggression. The flesh fly, Sarcophaga crassipalpis, was used to investigate ontogenetic and circadian changes in amines and aggression. Heads of male flies were analyzed for amine content using high performance liquid chromatography with electrochemical detection (HPLC-ECD) at 3 time points on each of 4 consecutive days in 2 light cycles, 12:12 LD and 15:9 LD. Both DA and OA levels decreased with age. Light-cycle dependent differences were observed for all amines in overall levels and patterns of change throughout the …


Net Impulse And Net Impulse Characteristics In Vertical Jumping, Satoshi Mizuguchi Aug 2012

Net Impulse And Net Impulse Characteristics In Vertical Jumping, Satoshi Mizuguchi

Electronic Theses and Dissertations

The purpose of this dissertation was to explore the potential use of net impulse and its characteristics in vertical jumping to monitor athletes' performance status and responses/adaptations to interventions. Five variables were proposed as net impulse characteristics: net impulse height and width, rate of force development, shape factor, and net impulse proportion. The following were then examined: 1) test-retest reliability of a new approach to identify net impulse in a force-time curve and of net impulse characteristics and criterion validity of the new approach; 2) effective measures of net impulse characteristics; 3) relationships between training-induced changes in its characteristics and …


Application Of Multivariate Statistical Methodology To Model Factors Influencing Fate And Transport Of Fecal Pollution In Surface Waters, Kimberlee K. Hall Aug 2012

Application Of Multivariate Statistical Methodology To Model Factors Influencing Fate And Transport Of Fecal Pollution In Surface Waters, Kimberlee K. Hall

Electronic Theses and Dissertations

Degraded surface water quality is a growing public health concern. While indicator organisms are frequently used as a surrogate measure of pathogen contamination, poor correlation is often observed between indicators and pathogens. Because of adverse health effects associated with poor water quality, an assessment of the factors influencing the fate and transport of fecal pollution is necessary to identify sources and effectively design and implement Best Management Practices (BMPs) to protect and restore surface water quality. Sinking Creek is listed on the State of Tennessee’s 303D list as impaired due to pathogen contamination. The need to address the listing of …


Analyzing The Interaction Between Melanocortin 5 Receptor, Melanocortin Receptor Accessory Protein 1, And Melanocortin 2 Receptor In Rainbow Trout, Domicinda M. Hill Jun 2012

Analyzing The Interaction Between Melanocortin 5 Receptor, Melanocortin Receptor Accessory Protein 1, And Melanocortin 2 Receptor In Rainbow Trout, Domicinda M. Hill

Electronic Theses and Dissertations

Using CHO cells we sought to explore and characterize the functional relationship of rainbow trout MC5 receptor (rtMC5R) with zebrafish MRAP1 (zfMRAP1) and rainbow trout MC2 receptor (rtMC2R), as well as how the effect of such relationships may play a significant role in Hypothalamic-Pituitary-Adrenal/Interrenal axis activation. This research demonstrated that rtMC5R can be successfully expressed and functionally activated in CHO cells and, in a manner similar to mammals, α-MSH is the preferred ligand for rtMC5R. The presence of MRAP1 does not seem to inhibit the expression or function of rtMC5R, rather it appears that it may increase expression and total …


Connexin-32 And Connexin-43 Immunoreactivity In Rodent Taste Buds, Amanda E. Bond Jun 2012

Connexin-32 And Connexin-43 Immunoreactivity In Rodent Taste Buds, Amanda E. Bond

Electronic Theses and Dissertations

Studies indicate that ATP is one of the primary neurotransmitters in taste transduction. ATP release occurs from taste cells via specific hemichannels such as pannexin/connexin hemichannels (Huang et al., 2007; Romanov et al., 2007). We hypothesize that Type II (receptor) and possibly Type III (presynaptic) cells release ATP at sites containing pannexin/connexin hemichannels. In this study, we examine the presence of connexin–32–LIR (Like Immunoreactivity) and connexin–43–LIR in rodent taste buds through immunocytochemical analysis and DAB (Di–amino–benzidine) immunoelectron microscopy. We observed that connexin–32–LIR co–localizes with P2X2–LIR in nerve fibers and in a small subset of NCAM–LIR cells. Connexin–32–LIR does not co–localize …


An Investigation Of Bacterial Ribonucleases As An Antibiotic Target, Ashley Denise Frazier May 2012

An Investigation Of Bacterial Ribonucleases As An Antibiotic Target, Ashley Denise Frazier

Electronic Theses and Dissertations

Antibiotics have been commonly used in medical practice for over 40 years. However, the misuse and overuse of current antibiotics is thought to be the primary cause for the increase in antibiotic resistance.

Many current antibiotics target the bacterial ribosome. Antibiotics such as aminoglycosides and macrolides specifically target the 30S or 50S subunits to inhibit bacterial growth. During the assembly of the bacterial ribosome, ribosomal RNA of the 30S and 50S ribosomal subunits is processed by bacterial ribonucleases (RNases). RNases are also involved in the degradation and turnover of this RNA during times of stress, such as the presence of …


Phylogeny Of Panthera, Including P. Atrox, Based On Cranialmandibular Characters, Leigha M. King May 2012

Phylogeny Of Panthera, Including P. Atrox, Based On Cranialmandibular Characters, Leigha M. King

Electronic Theses and Dissertations

Over the past 20 years both morphological and molecular phylogenies have been proposed for extant and extinct members of the family Felidae. However, there remain several discrepancies, particularly within the genus Panthera and the position of Panthera atrox. Consequently, morphologic characters from the skull and dentary were analyzed within Panthera (including all extant and one extinct taxa) to gain a better understanding of pantherine phylogeny. Multiple specimens of each taxon were analyzed, including: P. leo, P. tigris, P. onca, P. pardus , Uncia uncia, and Neofelis nebulosa. Four outgroups were used; Crocuta crocuta, Metailurus ssp., Proailurus lemanensis …


Cloning, Heterologous Expression In Yeast, And Biochemical Characterization Of Recombinant Putative Glucosyltransferase Clones 9 And 11 From Grapefruit (Citrus Paradisi), Anye Wamucho May 2012

Cloning, Heterologous Expression In Yeast, And Biochemical Characterization Of Recombinant Putative Glucosyltransferase Clones 9 And 11 From Grapefruit (Citrus Paradisi), Anye Wamucho

Electronic Theses and Dissertations

Flavonoids are plant secondary metabolites that play diverse roles in plants and human health. These compounds in most part exist in the glucosylated form. Grapefruit accumulates high levels of glucosylated flavonoids. Plant secondary product glucosyltransferases (GTs) catalyze the glucosylation reaction, but due to low homology at both the nucleotide and amino acid sequence level of different GTs, it is not possible to ascribe function based on sequence only. The hypotheses that PGT clones 9 and 11 are plant secondary product GTs and are biochemically regulated were tested. PGT 9 has been cloned into Pichia pastoris using the pPICZA and pPICZAα …


Cloning, Expression, And Biochemical Characterization Of Recombinant Putative Glucosyltransferases Clone 3 And 8 From Grapefruit (Citrus Paradisi), Deborah Hayford May 2012

Cloning, Expression, And Biochemical Characterization Of Recombinant Putative Glucosyltransferases Clone 3 And 8 From Grapefruit (Citrus Paradisi), Deborah Hayford

Electronic Theses and Dissertations

The grapefruit plant, Citrus paradisi, tends to accumulate high levels of flavonoid glycosides such as flavanones and flavones. Flavonoids have a vast array of important functions in plants and also in humans. Glucosyltransferases (GTs) are enzymes responsible for glucosylation reactions. In our pursuit to study the structure and function of flavonoid GTs, we have used molecular approaches to identify, clone, express, and functionally characterize the enzymes. This research was designed to test the hypothesis that PGT3 is a flavonoid glucosyltransferase and is subject to biochemical regulation. PGT3 has been tested for GT activity with compounds representing subclasses of flavonoids …


Fire-Derived Charcoal Along An Ecological Gradient In The Colorado Front Range, Christopher William Licata Mar 2012

Fire-Derived Charcoal Along An Ecological Gradient In The Colorado Front Range, Christopher William Licata

Electronic Theses and Dissertations

Terrestrial ecosystems are shaped by natural disturbances such as wildland fire. In the intermountain western United States, forests, shrub and grasslands adapt to repeated fires. An important long-term legacy of wildland fires is black C (BC) commonly referred to as char or charcoal. Black C is a recalcitrant C form that has been long known to influence soil physical, chemical, and biological processes that they vary across landscapes and over time. The objective of this research is to address two key areas in the emerging field of ecosystem BC research; 1) how much BC as charcoal C is formed per …


Dubious Role Of Mycobacterium Paratuberculosis In Pathogenesis Of Type I Diabetes, Saisathya Thanigachalam Jan 2012

Dubious Role Of Mycobacterium Paratuberculosis In Pathogenesis Of Type I Diabetes, Saisathya Thanigachalam

Electronic Theses and Dissertations

Background: Type 1 Diabetes mellitus (TIDM) is a chronic disorder in which the insulin producing beta cells are selectively self-destroyed. Although the etiology of the disease has not been determined, genetic dispositions such as SLC11A1 polymorphism in suffering patients have been reported. The role of pathogenic microorganisms such as Mycobacterium avium subspecies paratuberculosis (MAP) in TIDM has also been recently debated. MAP is already known to cause paratuberculosis in cattle and now it is a strong suspect of causing autoimmune diseases in humans such as Crohn’s disease, multiple sclerosis, autoimmune Thyroiditis, rheumatoid arthritis and autoimmune diabetes. We hypothesis that molecular …