Biotechnology Commons^™

A Robust Agroinfiltration Method, Bryce N. Trull

Masters Theses

Stable transformation of soybean (Glycine max) is a markedly slow and laborious process. Thus, a tool that enables rapid evaluation of genetic elements in planta is critical to advance complex research and genetic engineering in soybean. To that end, a substantially robust agroinfiltration method was innovated in this work. Agroinfiltration is a technique that leverages Agrobacterium-mediated transient transformation to deliver genetic elements to the cells of whole plant tissues, usually leaves. Several factors were found to be relevant to successful soybean leaf agroinfiltration, including genotype, surfactant, developmental stage, and Agrobacterium culture medium. The research represents not only …

Screening For Cry Proteins With Unique Receptors In Fall Armyworm (Spodoptera Frugiperda) And Corn Earworm (Helicoverpa Zea), Aria C. Deluna

Masters Theses

Bacillus thuringiensis (Bt) proteins have been the primary method for controlling Lepidopteran pests of corn and cotton over the past 20 years, due to their effectiveness and high level of target specificity. The fall armyworm (Spodoptera frugiperda) developed resistance to Cry1f, a Bt protein produced by both corn and cotton, within three years of registration in Puerto Rico. The evolution of resistance in pest insects poses as a threat to food safety as well as potentially resulting in economic losses of over $1 billion. The majority of Cry proteins follow a three domain (I to III) …

Drought-Stress-Inducible Synthetic Promoters In Rice (Oryza Sativa), Paolo Montano Tagaloguin

Masters Theses

Drought can potentially affect the global rice supply. Recent climate modeling studies projected a more frequent and intense drought scenario, especially in top producing and exporting countries worldwide. Several drought-tolerant genes had been identified in recent years, and transgenic approaches had been employed to develop drought-tolerant rice. However, the constitutive expression of some drought-tolerant genes resulted in undesirable phenotypes and metabolic burden. The use of an inducible synthetic promoter is advantageous in preventing the possible pleiotropic effects from constitutively expressing a drought-tolerant gene. In this study, rationally designed synthetic promoters based on poplar (Populus trichocarpa) cis-motifs were …

Improvements To Solanum Tuberosum Cv. ‘Desireé’ Cell Suspension Culture And Nicotiana Tabacum Cv. ‘Petit Havana’ Shoot Induction., Jessica Slade Layton

Masters Theses

Since the 1980s, progress in biotechnology has harnessed the incredible potential of plant biology. Plants have been engineered to be pest and herbicide resistant, enhance stress tolerance, and produce pharmaceutical proteins. Despite these feats of genetic engineering, plant tissue culture remains a limiting factor for future research. Unfortunately, the pressure to quickly innovate and produce novel products has pushed aside research to optimize tissue culture and exploring underlying molecular mechanisms for improved culture conditions. Efficient tissue culture methods are limited to a few plant taxa and are sometimes described in an oversimplified manner under the assumption they are facile to …

A Bug’S Life: Integration Of Anaerobic Digestion And Bioelectrochemical Systems For Enhanced Energy Recovery From Wastewater Solids And Other Waste Substrates, Jeff Ryan Beegle

Masters Theses

Organic waste streams, like domestic wastewater and municipal solid waste, have the potential to be used as feedstocks for biotechnology processes to produce high value products and energy. This thesis investigated the technological, economical, and environmental potential for integrated anaerobic digestion (AD) and bioelectrochemical system (BES) platforms as they were theoretically and physically evaluated for energy recovery from domestic wastewater. The first chapter of this thesis compared the theoretical energy efficiencies of converting waste directly into electricity, using AD and BES alone and in various combinations. This chapter reviewed the experimentally demonstrated energy efficiencies reported in the literature with comparisons …

Evaluation Of Hall’S Panicgrass (Panicum Hallii Vasey) As A Model System For Genetic Modification Of Recalcitrance In Switchgrass (Panicum Virgatum (L.)), Joshua Nathaniel Grant

Masters Theses

While switchgrass (Panicum virgatum (L.)) has long been recognized as a viable bioenergy feedstock, it and other plants have cell walls with recalcitrance to processing. Recalcitrance is recognized as a major barrier to broad adoption of switchgrass and other feedstocks for cellulosic bioenergy. In an effort to reduce recalcitrance, transgenic plants have been generated with altered cell wall phenotypes such as reduced lignin. Unfortunately, stable transformation of switchgrass and other C4 grasses is time intensive, costly, and genetic analysis is further complicated by polyploid genomic structures. Unlike switchgrass, which can be tetraploid to octoploid, a closely related species, Hall’s …

Switchgrass Extractives Have Potential As A Value-Added Antimicrobial Against Plant Pathogens And Foodborne Pathogens, Alexander Ian Bruce

Masters Theses

Panicum virgatum (switchgrass), a perennial grass native to North America, is a leading biomass feedstock candidate for the manufacture of cellulosic ethanol. Switchgrass is considered a viable option for biofuel production due to its cheap production cost and ability to grow on marginal land. Biofuel derived from switchgrass has been shown to be very energy efficient, producing 540% more renewable energy versus nonrenewable energy expended. Switchgrass-derived biofuel is also estimated to have greenhouse gas emissions that are 94% lower than emissions from gasoline (Schmer et al 2008). Biofuels are created through biochemical processes that utilize various enzymes and microorganisms for …

Rapid Molecular Detection And Population Genetics Of Pityophthorus Juglandis, A Vector Of Thousand Cankers Disease In Juglans Spp., Emel Oren

Masters Theses

Thousand Cankers Disease (TCD) is a disease complex involving the fungal pathogen Geosmithia morbida, an insect vector Pityophthorus juglandis, and the hosts, Juglans spp. and Pterocarya spp. Signs and symptoms of TCD include crown thinning due to branch dieback, yellowing and wilting of the leaves, appearance of epicormic shoots, numerous entrance/exit holes, gallery formation by P. juglandis, and the development of small, dark brown cankers underneath the bark. TCD originally described from western U.S., has now expanded to eastern U.S. and northwestern Italy. The disease complex is often difficult to diagnose due to the absence of symptoms …

Enzyme Catalyzed Alginate Nanogels For Drug Delivery, Danna Nichole Sharp

Masters Theses

Developing nanoscale carriers for the delivery of therapeutics is an important topic of investigation in current biomedical research. As opposed to traditional drug delivery systems, nanoscale systems offer enhanced tissue and cell permeation in addition to reducing drug elimination from the body. Biological based therapeutics such as DNA and proteins are now widely employed in medical applications and research has focused on using nanoscale drug delivery systems to administer these more effectively. Current synthesis methods of nanoscale biotherapeutic carriers face significant challenges. Among these are creating carriers with: sizes between 10-200 nm, low polydispersity, and non-cytotoxic materials. In this thesis, …

Evaluation Of The Over-Expression Of A Miscanthus X Giganteus Ppdk (C4ppdk1) In Switchgrass (Panicum Virgatum) For Improved Cold Temperature C4 Photosynthesis, Mathew Christian Halter

Masters Theses

Switchgrass (Panicum virgatum) has been proposed as a potential biofuel feedstock to aid in the displacement of petroleum-based combustible fuels over the course of the next several decades. Improving the yield potential of this perennial grass is therefore of economic interest. Increased net ethanol yields can be achieved in cellulosic feedstocks via two means: 1. Improved sugar release from digestible cell wall materials, 2. Increased overall biomass yield. The latter is the subject of this study.

As a C4 photosynthetic plant, switchgrass is highly productive in the hot, humid climate of the southeastern United States. By bypassing the …

Value-Added Lignin Based Carbon Fiber From Organosolv Fractionation Of Poplar And Switchgrass, Andreas Attwenger

Masters Theses

Carbon fibers have unique properties that include high strength, low density and excellent chemical and thermal resistance. However, they have a low level of utilization because of their high price; typically around $30/kg for an entry level polyacrylonitrile (PAN) based carbon fiber. Low-cost carbon fibers derived from lignin are currently being investigated at the University of Tennessee, because using lignin as a precursor could significantly reduce production costs. Lignins obtained from the pulp and paper and the emerging biofuel industries have the potential to be used for carbon fiber production, however, they are typically unsuitable because of the high levels …

Bioconfinement Of A Putatively Sterile Nicotiana Hybrid And Development Of Tools For Assessing Gene Flow, John Hollis Rice

Masters Theses

Production of transgenic crops in open field environments is an ongoing concern of due to the potential for gene flow. New transgenic crops, such as plant-made-pharmaceuticals may generate additional concerns about effects of adventitious transgenes. Use of a bioconfinement strategy may alleviate any consequences by preventing gene flow. The following chapters discuss previous and current research on gene flow, testing of a Nicotiana hybrid system for bioconfinement efficiency, and development of methods for transgene detection. The candidate ‘platform plant’ that was tested is a Nicotiana hybrid (Nicotiana tabacum ‘TN 90’ × Nicotiana glauca) previously identified to be sexually …

Consequences Of Gene Flow And Transgene Introgression In Hybrids Between Transgenic Brassica Napus And Its Weedy Wild Relative Brassica Rapa, Reginald Jason Millwood

Masters Theses

The adventitious presence of transgenes and their potential impact on the environment has been a topic of concern for many years. To address these concerns the following chapters discuss past and current research of gene flow and introgression, methods for transgene detection and monitoring, and the results from field-level experiments using artificially introgressed advanced generation hybrids. The field studies were designed to be a worst-case scenario where hybrids were produced by hand-crossing transgenic Brassica napus (AACC, 2n = 38) and its weedy wild relative Brassica rapa (AA, 2n = 20). B. napus was transgenic for the green fluorescent protein [m-GFP-5 …

Functional Characterization Of An Endoglucanase From Tribolium Castaneum (Tceg1) In Saccharomyces Cerevisiae And Characterization Of Cellulolytic Activity In The Digestive Fluids Of Thermobia Domestica (Zygentoma: Lepismatidae), Derek Mychel Shirley

Masters Theses

Cellulosic ethanol has the potential to be a significant biofuel due to its sustainability and high energy yield. However it is the recalcitrance of cellulose that presents a costly road block in the economic feasibility of cellulosic ethanol production. The enzymatic degradation of lignocellulosic biomass has the greatest potential for reducing the production costs of this process. While many commercially viable cellulases have been identified in bacteria and fungi, insects remain a relatively untapped source of these enzymes. In fact recent studies have shown that insects produce highly active endogenous cellulases capable of completely hydrolyzing cellulose to glucose, without the …

Intellectual Property And Policy Issues In Biotechnology, Amy Iver Yancey

Masters Theses

Intellectual property, particularly patents, plays a major role in innovation and discovery in biotechnology. Likewise, since the passage of the Bayh-Dole Act in 1981, patents have become an increasingly important factor in U.S. university-driven basic research, especially in the life sciences where patented technologies have transformed agriculture. Specifically, this paper looks at the potential impacts of these trends on university driven research, the university researcher, the pharmaceutical industry, and the farm sector with an emphasis on recent and pending court cases and legislation. This paper examines policy and adoptions issues in biotechnology and biomedicine in depth and touches on important …

Study Of Population Diversity Of Toxoplasma Gondii, Debashree Majumdar

Masters Theses

Toxoplasma gondii, the causal agent of toxoplasmosis, is an important water and food borne protozoan parasite. T. gondii was previously shown to have a distinct clonal population structure composed of Type I, II and III lineages in North America and Europe. But more recent studies demonstrated high diversity in South America. In the present project we have conducted an intensive study of the population diversity of T. gondii and surveyed the extent of genetic variation among natural T. gondii isolates on a global scale in order to better understand the population dynamics and pathogenesis of this parasite. To this …

Fungal Endophytes Enhance Growth And Production Of Natural Products In Echinacea Purpurea (Moench.), Richard James Gualandi Jr.

Masters Theses

Echinacea purpurea is a native herbaceous perennial with substantial economic value for its medicinal and ornamental qualities. Arbuscular mycorrhizae are symbiotic fungi that form relationships with plant roots and are known to enhance growth in the host. Mycorrhizae and other fungal endophytes often affect stress resistance and secondary metabolism in the host, as well as the ecology of other endophytes in the plant. A newly emerging paradigm in sustainable biotechnique is the targeted use of fungal endophytes to enhance growth and secondary metabolism in crops. Many of the therapeutic compounds in E. purpurea could be affected by fungal colonization. In …

Developing A Technique For Evaluating Weed-Specific Mapping Systems, Philip Brooks Allen

Masters Theses

Federal regulation and public awareness of agricultural chemical use have fueled precision agriculture research for the last decade. An extensive body of research on potential reduction of herbicide inputs by automated patch-spraying or site-specific management has developed. Two dominant methods have developed for site-specific application of herbicide. Map-based systems use predefined application maps to direct herbicide application and sensor-based systems use real-time weed sensors to identify and treat weeds as the sprayer moves through the field. Weed maps, generated for map-based application of herbicide are beneficial for out-of-field decision-making but are labor intensive to create and sensitive to many types …

Preferential Flow And Colloids: Their Influence On The Transport Of Phosphorus, Tara Johanna Garrett

Masters Theses

Although strongly adsorbing ions are relatively immobile within soil, ion transport can be enhanced by preferential flow and by adsorption of ions to mobile colloids. The primary objective of this research was to determine the influence of preferential flow paths on the transportation of phosphorus (P) through a soil profile. Secondary objectives were to determine the effect of fertilizer type (inorganic vs. organic) and colloids on the transport of P.

Eight soil monoliths with a diameter of 0.3 m and a length of 0.75 m were collected from the Water Quality field site at the Ames Plantation. Four monoliths were …

Mussel Habitat Mapping In The Big South Fork National River And Recreation Area (Biso), Adam John Fiscor

Masters Theses

A new method to map freshwater mussel habitats was developed and tested in theBigSouthForkNationalRiverand Recreation Area (BISO). The procedure involved using an Underwater Video Mapping System (UVMS) to record river substrate information in conjunction with Global Positioning System (GPS) to create

geo-referenced video footage. Simultaneously, the river surface features were

video-recorded using a similar geo-referenced video mapping system. Images from both videos were evaluated and used to produce habitat classifications in a Geographic Information System (GIS) format. The focus of the project was on mapping attributes in the river that are significant to freshwater mussel habitats. These attributes characterize river …