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2009

Utah State University

Theses/Dissertations

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Full-Text Articles in Life Sciences

Designing An Instrument Based On Native Fluorescence To Determine Soil Microbial Content At A Mars Analog Site, Heather D. Smith Dec 2009

Designing An Instrument Based On Native Fluorescence To Determine Soil Microbial Content At A Mars Analog Site, Heather D. Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

For this research project we designed an instrument to detect bacteria via biomolecular fluorescence. We introduce the current understanding of astrobiology, our knowledge of life beyond Earth, and the commonality of Earth life as it pertains to the search for life on Mars. We proposed a novel technique for searching for direct evidence of life on the surface of Mars using fluorescence. We use the arid region of the Mojave Desert as an analog of Mars. Results indicate the fluorescence of the biotic component of desert soils is approximately as strong as the fluorescence of the mineral component. Fluorescence laboratory …


Summer Home Range Fidelity In Adult Female Elk (Cervus Elaphus) In Northwestern Colorado, April M. Brough Dec 2009

Summer Home Range Fidelity In Adult Female Elk (Cervus Elaphus) In Northwestern Colorado, April M. Brough

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Understanding the degree of spatial fidelity of individuals within a species increases our ability to manage appropriately. Elk (Cervus elaphus) is a highly managed species in the Intermountain West, but there is little research evaluating summer home range fidelity of individual elk. We evaluated fidelity of 72 adult female elk to individual summer-fall home ranges in the White River study area in northwestern Colorado during two consecutive summers. Based on individual kernel-estimated utilization distributions, we used (1) the Volume of Intersection (VI) statistic and (2) interannual distances between centers of mass to compare summer range overlap and distribution. …


Effects Of Coyote Removal On Pronghorn And Mule Deer Populations In Wyoming, Dylan Earl Brown Dec 2009

Effects Of Coyote Removal On Pronghorn And Mule Deer Populations In Wyoming, Dylan Earl Brown

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I studied the relationship between coyote (Canis latrans) removal and pronghorn (Antilocapra americana) and mule deer (Odocoileus hemionus) density and fawn:doe ratios in southwest Wyoming and northeast Utah in 2007 and 2008. Coyote removal variables studied included the number of coyotes removed, ground hours worked, total hours worked, coyotes removed/aerial gunning hour, coyotes removed/ground work hour, and coyotes removed/total effort hour. None of the variables explained changes observed in fawn:doe ratios of pronghorn or mule deer. The number of coyotes removed, ground hours worked, total hours worked, and coyotes removed/aerial gunning hour were positively …


The Effects Of Social Status And Learning On Captive Coyote (Canis Latrans) Behavior, Lynne Barbara Gilbert-Norton Dec 2009

The Effects Of Social Status And Learning On Captive Coyote (Canis Latrans) Behavior, Lynne Barbara Gilbert-Norton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Many canids live within hierarchical social systems that could promote differences in learning or in behavior between ranked individuals. Differences in foraging and territorial behavior have been observed between ranked coyotes (Canis latrans), yet effects of learning and social status on coyote behavior are not thoroughly understood. I explored a) coyote response to an artificial scent boundary and whether response differed by status, b) how foraging coyotes tracked temporal resource change, and c) how coyotes find spatially distributed food, and the effect of dominance on foraging behavior. I used male/female pairs of captive coyotes at the National Wildlife Research Center …


Herbicide, Salinity, And Flooding Tolerance Of Foxtail Barley (Hordeum Jubatum L.) And Desirable Pasture Grasses, Karl R. Israelsen Dec 2009

Herbicide, Salinity, And Flooding Tolerance Of Foxtail Barley (Hordeum Jubatum L.) And Desirable Pasture Grasses, Karl R. Israelsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Research trials performed in the greenhouse compared the tolerance and response of Hordeum jubatum and desirable pasture grass species to herbicides, salinity, and flooding. Desirable grass species used in this study included: 'Fawn' tall fescue (Festuca arundinaceae), 'Garrison' creeping foxtail (Alopecurus arundinaceus), 'Palaton' reed canarygrass (Phalaris arundinacea), 'Climax' timothy (Phleum pratense), 'Alkar' tall wheatgrass (Thinopyrum ponticum), 'Potomac' orchardgrass (Dactylis glomerata), and 'Mustang' altai wildrye (Leymus angustus). Tolerance to herbicides, salinity, and flooding varied significantly among grass species. Herbicide tolerance was tested using four herbicides at five …


Alternative Sampling And Analysis Methods For Digital Soil Mapping In Southwestern Utah, Colby W. Brungard Dec 2009

Alternative Sampling And Analysis Methods For Digital Soil Mapping In Southwestern Utah, Colby W. Brungard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Digital soil mapping (DSM) relies on quantitative relationships between easily measured environmental covariates and field and laboratory data. We applied innovative sampling and inference techniques to predict the distribution of soil properties, soil attributes, taxonomic classes, and dominant vegetation across a 30,000-ha complex Great Basin landscape in southwestern Utah. This arid rangeland was characterized by rugged topography, diverse vegetation, and intricate geology. Environmental covariates calculated from digital elevation models (DEM) and spectral satellite data were used to represent factors controlling soil development and distribution. We investigated optimal sample size and sampled the environmental covariates using conditioned Latin Hypercube Sampling (cLHS). …


Discovering Metabolic Networks Of Bovine Fertilization, Erin Lynn Young Dec 2009

Discovering Metabolic Networks Of Bovine Fertilization, Erin Lynn Young

Undergraduate Honors Capstone Projects

At the time of fertilization, a dramatic change occurs in the oocyte that transforms this cell from a metaphase arrested state into a metabolically active and dynamic state. The view of the flow of biological processes within organisms has recently shifted from that of a linear path to a more complex network. Biological processes are no longer thought of in the simple terms of DNA to RNA, RNA to proteins, and proteins to final activity. It is now known that many biological processes involve interconnected networks and feedback loops in which DNA, RNA, proteins, and metabolites perform specific roles. We …


Effects Of Starch Addition On Low Fat Rennet Curd Properties And Their Partitioning Between Curd And Whey, Kelly Marie Larsen Dec 2009

Effects Of Starch Addition On Low Fat Rennet Curd Properties And Their Partitioning Between Curd And Whey, Kelly Marie Larsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study determined the impact of starches on the properties of low fat rennet curd as measured by microstructural and instrumental analysis. In experiment 1, 17 starches were initially screened for swelling power, impact of curd yield at 5 g/L and 10 g/L in milk, and settling in rennet-induced partially acidified low fat curd.

Starches examined were narrowed down to five in experiment 2; they included: modified waxy corn starch, waxy rice starch, instant tapioca starch, dextrin, and a modified tapioca starch. These starches were added to skim milk to make rennet-induced partially acidified milk gels. Gels were made by …


Disturbance Ecology And Vegetation Dynamics At Varying Spatial And Temporal Scales In Southern Rocky Mountain Engelmann Spruce Forests, R. Justin Derose Dec 2009

Disturbance Ecology And Vegetation Dynamics At Varying Spatial And Temporal Scales In Southern Rocky Mountain Engelmann Spruce Forests, R. Justin Derose

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

High-severity disturbances are the primary drivers of Engelmann spruce-subalpine fir ecosystems in the southern Rocky Mountain. Recently, an unprecedented, landscape-wide (at least 250 km2) spruce beetle outbreak killed virtually all the Engelmann spruce on the Markagunt Plateau in southwestern Utah, USA. Results from dendroecological analyses suggested the combination of antecedent disturbance history and drought-driven stand development was responsible for creating suitable host conditions prior to the recent outbreak. Multiple and consistent lines of evidence suggested mixed- and high-severity fires shaped the development of the Markagunt Plateau. Subsequent stand development, influenced by species-specific differential tree-ring response to drought, resulted in the …


The Effect Of Irrigation Diversions On The Mountain Whitefish (Prosopium Williamsoni) Population In The Big Lost River, Patrick Allen Kennedy Dec 2009

The Effect Of Irrigation Diversions On The Mountain Whitefish (Prosopium Williamsoni) Population In The Big Lost River, Patrick Allen Kennedy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Management agencies documented a decline in the mountain whitefish (Prosopium williamsoni) population on the Big Lost River, and unscreened diversions were recognized as a potential factor for this decline. Research suggests the Big Lost River mountain whitefish population is genetically unique, and it has been petitioned for protection under the Endangered Species Act. In 2007, a basin-wide synopsis of diversions was conducted to describe relative entrainment and identify diversions that entrained the most mountain whitefish. This larger scaled synopsis facilitated a more precise assessment of entrainment by a subset of diversions in 2008. In 2008, the volume that …


Ecological Effects Of Genotypic Diversity On Community And Ecosystem Function, Megan K. Kanaga Dec 2009

Ecological Effects Of Genotypic Diversity On Community And Ecosystem Function, Megan K. Kanaga

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Genotypic diversity within populations can have important evolutionary consequences, but the ecological effects of intraspecific genetic variation on community and ecosystem function have only been studied in a few systems. I present the results of a three-year study designed to address the ecological impacts of genotypic diversity in quaking aspen (Populus tremuloides Michx.), using aspen genotypes planted across genotypic diversity levels (monoculture and mixture) and watering treatment levels (well-watered and water-limited). First, I demonstrated that significant variation exists among genotypes for a wide range of growth, morphological and physiological traits, and quantified high heritability and coefficient of genetic variation …


Investigating Methods To Reduce Black Bear (Ursus Americanus) Visitation To Anthropogenic Food Sources: Conditioned Taste Aversion And Food Removal, Kari D. Signor Dec 2009

Investigating Methods To Reduce Black Bear (Ursus Americanus) Visitation To Anthropogenic Food Sources: Conditioned Taste Aversion And Food Removal, Kari D. Signor

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Conflicts between humans and black bears (Ursus americanus) jeopardize the safety of both humans and bears, especially when bears become food-conditioned to anthropogenic food sources in areas such as campgrounds. Interest in using non-lethal techniques, such as aversive conditioning, to manage such conflicts is growing. I conducted a captive experiment at The Wildlife Science Center in Minnesota and two field experiments in the La Sal Mountains, Utah, to investigate the effects of taste aversion conditioning using thiabendazole (TBZ) with a novel flavor cue and food removal on black bear food consumption and visitation to human food sources. In …


An Alternative Futures Study For The Uintah Basin: Exploring 2030, Nicholas E. Kenczka May 2009

An Alternative Futures Study For The Uintah Basin: Exploring 2030, Nicholas E. Kenczka

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The Uinta Basin is located within the Colorado Plateau consisting of various ecosystems ranging from high elevation mountainous regions to sage and juniper woodlands. The basin rests in the northeast corner of Utah with the largest communities being Vernal, Roosevelt, and Duchesne. Other key features include the Flaming Gorge Recreation Area, Green River, and Dinosaur National Monument. The basin historically has been a major region for natural resource extraction, and the population fluctuation has mirrored the "boom" and "bust" cycles of the industry. The Uintah Basin has recently recognized the need for developing a comprehensive plan for identifying the critical …


Alternative Futures 2030: Ogden Valley, Louis Alan Hurst May 2009

Alternative Futures 2030: Ogden Valley, Louis Alan Hurst

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Ogden Valley is a high mountain community located in the northern Wasatch Mountain Range (Figure 1), and is located entirely within Weber County, Utah. Three communities sit within the valley: Huntsville, Eden, and Liberty. Early Mormon settlers established these communities in the mid-1800s; however, only the town of Huntsville is incorporated. The rural valley is in close proximity to the densely populated Wasatch Front, in particular, Ogden City. Ogden Valley is approximately 331 square miles and has an elevation that ranges between 4400 and 9700 feet. This wide range in elevation provides a diverse environment for humans, wildlife , and …


Predation On Domestic Sheep On Summer Range Lands In Southwestern Utah, Brian Carl Palmer May 2009

Predation On Domestic Sheep On Summer Range Lands In Southwestern Utah, Brian Carl Palmer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Much of the decline of the U.S. sheep industry has been attributed to losses caused by predators. Most predatory losses are inflicted on lambs rather than ewes. Losses have historically ranged from 4-8% of lamb crops, inflicting significant financial loss on ranchers. However, most research providing data on sheep predation is over 20 years old. Changes in the sheep industry as well as predation rates may make previous loss rates inapplicable to current conditions. Coyotes (Canis latrans) are the primary predator of concern when it comes to sheep losses, but increasingly, cougars (Felis concolor) and black …


Speciation, Species Concepts, And Biogeography Illustrated By A Buckwheat Complex (Eriogonum Corymbosum), Mark W. Ellis May 2009

Speciation, Species Concepts, And Biogeography Illustrated By A Buckwheat Complex (Eriogonum Corymbosum), Mark W. Ellis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The focus of this research project is the complex of infraspecific taxa that make up the crisp-leaf buckwheat species Eriogonum corymbosum (Polygonaceae), which is distributed widely across southwestern North America. This complex provides an ideal taxonomic group for research into population relationships and speciation. To avoid unnecessary debates about taxonomic validity or contentious issues regarding appropriate species definitions, the historical evolution of the species concept is first reviewed in detail, demythologizing an often-assumed species problem. Following that review, the E. corymbosum complex is examined specifically.

Although eight varieties of E. corymbosum are currently recognized based on morphological characters, this group …


Watershed-Scale Analysis Of Riparian Buffer Function, Molly Van Appledorn May 2009

Watershed-Scale Analysis Of Riparian Buffer Function, Molly Van Appledorn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The ability of riparian buffers to filter undesirable nutrients from upland sources has long been recognized as an important ecosystem service for maintaining or improving water quality, and as a result, many land management strategies have been built around the preservation or restoration of buffer zones. Newly derived flow-path metrics have shown great promise as a way to assess riparian buffer function at the watershed scale but a thorough investigation of metric performance was necessary. The goals of this study were to: 1) test the independence of flow-path metrics from traditional metrics using a spatially extensive, independent sample of watersheds, …


Inducing A Normal Phenotype In Breast Epithelial Cells Using A Three-Dimensional Basement Membrane Extract Culture System: A Study On The Reversion Of Cancer, Ross H. Booth May 2009

Inducing A Normal Phenotype In Breast Epithelial Cells Using A Three-Dimensional Basement Membrane Extract Culture System: A Study On The Reversion Of Cancer, Ross H. Booth

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Experimentally, traditional developmental models and transgenic animals consistently underscore the importance of studying cell behavior in the correct tissue context. However, live animal experimentation is inherently complex, and systematic assessment of the effects of individual variables, such as cell shape and matrix compliance on cell behavior, is extremely difficult at best. Two-dimensional monolayer culture of key individual cell types has provided abundant, fundamental information on cell response, but cannot be used to show the normal phenotype of breast epithelial cells. Furthermore, their results often fail to translate into in vivo and clinical studies. It has been previously established that normal …


Effect Of Surface Stability On Core Muscle Activity During Dynamic Resistance Exercises, Brennan J. Thompson May 2009

Effect Of Surface Stability On Core Muscle Activity During Dynamic Resistance Exercises, Brennan J. Thompson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to compare core muscle activity during resistance exercises performed on stable ground versus an unstable surface and to examine whether lifting at different relative intensities affects core muscle activity levels. Twelve trained men performed four different movements including the deadlift, back squat, military press, and curl. Surface electromyography (EMG) was utilized to assess the activity of the rectus abdominis, external oblique, transversus abdominis, and erector spinae muscles. Participants performed each movement under three separate conditions including standing on stable ground with 50% of their one repetition maximum (1-RM), standing on a BOSU balance trainer …


The Bioactive Properties Of Syringomycin E-Rhamnolipid Mixtures And Syringopeptins, Mekki F. Bensaci May 2009

The Bioactive Properties Of Syringomycin E-Rhamnolipid Mixtures And Syringopeptins, Mekki F. Bensaci

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The need for new antimicrobial agents has become important in the last decade due to emerging resistance to a number of conventional antimicrobial agents. New approaches and sources are needed to generate novel and effective antimicrobials. For example, synergistic combinations between two or more agents may lead to new antimicrobial therapies. Furthermore, the increase in health problems caused by the exposure to agricultural crop pesticides and synthetic fungicides and the emerging development of organic farming has increased the necessity to develop natural products than can be used safely in controlling crop diseases.

In this work, I present the first studies …


Mechanisms Of Induced Cell Death In Bluetongue Virus Challenged Human Cell Lines, Justin Darrel Hoopes May 2009

Mechanisms Of Induced Cell Death In Bluetongue Virus Challenged Human Cell Lines, Justin Darrel Hoopes

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Bluetongue virus (BTV) is a pathogenic member of the Reoviridae family. BTV does not cause disease in humans, but is capable of selectively infecting and killing certain transformed human cell lines. Understanding BTV's oncotrophism may lead to new therapeutics for treating cancer. This study focused on the underlying mechanisms of BTV-induced cell death in carcinoma cell lines. It was our hypothesis that BTV infects human carcinoma transformed cells, produces mRNA and protein, induces a strong inflammatory response, induces mitogen activated protein kinase (MAPK)-based pro-apoptotic signaling, inhibits PKB-based signaling, and eventually kills the cell by inducing apoptosis.

Three carcinoma cell lines …


Predicting The Growth Potential Of A Shallow, Warm-Water Sport Fishery: A Spatially Explicit Bioenergetics Approach, Samuel Kirk Dahle May 2009

Predicting The Growth Potential Of A Shallow, Warm-Water Sport Fishery: A Spatially Explicit Bioenergetics Approach, Samuel Kirk Dahle

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Capturing the range of fish consumption and growth potential of large, heterogeneous lentic systems can be challenging due to strong gradients in productivity, the diversity of habits types present, and in some cases, site-specific water quality issues. Cutler Reservoir (Utah, USA) displays a high degree of spatial and temporal variation in physical conditions and potential water quality limitations for fish, including high summertime water temperature and large, diel fluctuations in dissolved oxygen concentrations. The combination of bioenergetics modeling and GIS spatial analysis offers a promising interface for quantifying the fish consumptive and growth potential across a spatially and temporally heterogeneous …


Application Of Electrified Fladry To Decrease Risk Of Livestock Depredation By Wolves (Canis Lupus), Nathan J. Lance May 2009

Application Of Electrified Fladry To Decrease Risk Of Livestock Depredation By Wolves (Canis Lupus), Nathan J. Lance

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Wolf (Canis lupus) predation on livestock can cause economic and emotional hardships for livestock producers, complicating the balance of wolf conservation with other human interests. New management tools that decrease risk of predation may offer additional flexibility or efficiency for both livestock producers and management agencies. I examined 1) the efficacy of electrified fladry compared to fladry at protecting a food source from wolves in captivity, 2) the efficacy of electrified fladry for reducing wolf use of pastures and preventing depredations, and 3) the applicability of electrified-fladry. In captivity I tested the reaction from 15 groups (46 wolves) …


Social Acceptability Of Conifer Control And Sagebrush Restoration In The Northern Rocky Mountain Region, Cameron G. Nay May 2009

Social Acceptability Of Conifer Control And Sagebrush Restoration In The Northern Rocky Mountain Region, Cameron G. Nay

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In the past two centuries, woody plant species have increased in density and extent throughout the rangelands of North America. This encroachment generally has undesirable effects on hydrological function, forest resources, and plant community composition. Encroachment of Douglas-fir (Pseudotsuga menziesii) and ponderosa pine (Pinus ponderosa) into sagebrush communities is occurring in the Northern Rocky Mountain region. Removal and restoration treatments are often proposed to manage this issue, mainly prescribed fire, mechanical destruction, and/or herbicide use. Several contextual factors may affect public level of acceptability for such treatments. The issue frames used to present this problem to …


Taste Sensitivity To 6-N-Propylthiouracil (Prop) As A Biological Marker For Vulnerability To Stress In Mothers And Children, Deann Jones May 2009

Taste Sensitivity To 6-N-Propylthiouracil (Prop) As A Biological Marker For Vulnerability To Stress In Mothers And Children, Deann Jones

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Some people are genetically more vulnerable to stress than others, leading them towards poorer outcomes following stressful events. Mothers' vulnerability to stress may, in turn, influence their children, leading their children towards poor outcomes as well. A biological marker of vulnerability to stress may indicate mothers who are at greater risk for experiencing parenting stress, depression, and less support of the infant's emotional development, and infants who are at greater risk for development of poor emotion regulation and behavior problems. Taste sensitivity to propylthiouracil (PROP) is proposed as a biological marker of stress vulnerability in mothers and children. This research …


Evaluation Of Macroinvertebrates As A Food Resource In The Assessment Of Lotic Salmonid Habitat, Nicholas P. Weber May 2009

Evaluation Of Macroinvertebrates As A Food Resource In The Assessment Of Lotic Salmonid Habitat, Nicholas P. Weber

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Criteria used to characterize lotic salmonid habitat are often based on observed correlations between physical habitat characteristics and salmonid abundances. A focus on physical habitat features ignores other habitat components, such as an adequate supply of food that set the physiological limitations on salmonid growth and survival. This study outlines the development of a habitat assessment approach that focuses on how invertebrate food availability interacts with stream temperatures to determine salmonid growth potentials. Abundances of benthic and drifting invertebrate communities, stream temperatures, and juvenile steelhead trout (Onchorhynchus mykiss gairdneri) summer growth rates and abundances were measured within 10 …


Patch-Scale Effects Of An Invasive Ecosystem Engineer On The Structure And Function Of A Eutrophic Stream, Samuel J. Hochhalter May 2009

Patch-Scale Effects Of An Invasive Ecosystem Engineer On The Structure And Function Of A Eutrophic Stream, Samuel J. Hochhalter

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Recent theoretical and technological advances in ecosystem science have dramatically expanded the ways in which scientists can pursue and explore ecological questions. For my thesis research, I integrated the recent theoretical concept of organisms as ecosystem engineers with the relatively recent development of stable isotope tracer tests to ask the question: how does the invasive common carp affect stream ecosystem structure and function? To investigate the structuring role of carp, I measured autotroph seasonal distribution and abundance and macroinvertebrate seasonal abundance and diversity within two stream reaches in Spring Creek, Utah, USA; one with low carp biomass (LCB) and one …


Surgical Sterilization Of Coyotes To Reduce Predation On Pronghorn Fawns, Renee Seidler May 2009

Surgical Sterilization Of Coyotes To Reduce Predation On Pronghorn Fawns, Renee Seidler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Coyote (Canis latrans) predation accounts for the majority of neonatal pronghorn (Antilocapra americana) mortality in many areas and may influence local population declines. Current techniques used to manage coyote predation on wildlife species generally focus on lethal control methods. However, these methods may be controversial to the general public. Coyote sterilization is an alternative predation control method which is more acceptable to the public and has been shown to be effective in reducing sheep predation. We hypothesized that surgical sterilization of coyotes may increase pronghorn fawn survival; in the same way it reduces coyote predation on …


Characterization Of The Substrate Specificity And Mechanism Of Protein Arginine Methyltransferase 1, Whitney Lyn Wooderchak May 2009

Characterization Of The Substrate Specificity And Mechanism Of Protein Arginine Methyltransferase 1, Whitney Lyn Wooderchak

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Protein arginine methyltransferases (PRMTs) posttranslationally modify protein arginine residues. Type I PRMTs catalyze the formation of monomethylarginine (MMA) and asymmetric dimethylarginine (ADMA) via methyl group transfer from S-adenosyl methionine onto protein arginine residues. Type II PRMTs generate MMA and symmetric dimethylarginine. PRMT-methylation affects many biological processes. Although PRMTs are vital to normal development and function, PRMT-methylation is also linked to cardiovascular disease, stroke, multiple sclerosis, and cancer.

Thus far, nine human PRMT isoforms have been identified with orthologues present in yeast, plants, and fish. PRMT1 predominates, performing an estimated 85% of all protein arginine methylation in vivo. Yet, the substrate …


A Comparative Study Of The Structural Features And Kinetic Properties Of The Mofe And Vfe Proteins From Azotobacter Vinelandii, Miguel Alejandro Pabon Sanclemente May 2009

A Comparative Study Of The Structural Features And Kinetic Properties Of The Mofe And Vfe Proteins From Azotobacter Vinelandii, Miguel Alejandro Pabon Sanclemente

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Biological nitrogen fixation is accomplished in the bacterium Azotobacter vinelandii by means of three metalloenzymes: The molybdenum, vanadium, and iron-only nitrogenase. The knowledge regarding biological nitrogen fixation has come from studies on the Mo-dependent reaction. However, the V- and Fe-only-dependent reduction of nitrogen remains largely unknown.

By using homology modeling techniques, the protein folds that contain the metal cluster active sites for the V- and Fe-only nitrogenases were constructed. The models uncovered similarities and differences existing among the nitrogenases regarding the identity of the amino acid residues lining pivotal structural features for the correct functioning of the proteins. These differences, …