Biotechnology Commons^™

Diversity Of Bacteriophage In Burkholderia Species, Abigail Price

Honors Projects

Bacteriophages are viruses that infect and replicate within bacteria and offer the potential of a therapeutic alternative to chronic infections that do not respond to antibiotic-based therapies. B. vietnamiensis is one of a number of Burkholderia species involved with chronic drug resistant infections in the lungs of individuals with compromised respiratory systems, as found in those with chronic obstructive pulmonary disease and, most especially, are of particular significance in patients with cystic fibrosis. The diversity of the Burkholderia species is explored by using online databases and looking at bacteriophage or phage-encoding viruses found in B. vietnamiensis. The open reading frames …

Suspended Carbon Nanowire Biosensor For Rapid And Label-Free Salmonella Detection, Thiha Aung

Student Works (2020-2029)

Carbon, the building block life, is rapidly becoming the building block of nextgeneration electronics and sensor materials. Of many ways to handle nanocarbon materials, Carbon Microelectromechanical Systems (C-MEMS) emerges as a unique way for top-down fabrication of three-dimensional carbon micro to nanostructures. In this work, the use of C-MEMS techniques in nanowire biosensor fabrication is explored. Two main hindrances in the use of C-MEMS carbon structures for biosensing lie in miniaturization to nanoscale sensor material and inertness of as-fabricated carbon. This dissertation presents ways to overcome these limitations. First, miniaturization to patterned sub-100 nm carbon nanowires was achieved by optimization …

Hexadecane Petroleum, And Biofuel Utilization In Marine Bacteria Isolated From Ballast Tanks, Alex Yashchenko

Graduate Theses

This study characterized the growth of bacteria isolated from ballast tank fluids in hexadecane, petroleum, plant, and algae-derived fuels. The study was performed to explore the capacity of ballast tank isolates to survive and grow within fuels that may be stored within ballast tanks. Results of the hexadecane analysis indicated that most isolates had higher viable cell counts in media supplemented with hexadecane. Members of Alteromonas, Pseudoalteromonas, and a single Brevundimonas species had viable cell counts that were one or several orders ofmagnitude greater than that of controls. Results offuel analysis indicated higher viable cell counts in pure JP-5 and …

Metabolic Feedback Inhibition Influences Metabolite Secretion By The Human Gut Symbiont Bacteroides Thetaiotaomicron, Jennie L. Catlett, Jonathan Catazaro, Mikaela Cashman, Sean Carr, Robert Powers, Myra B. Cohen, Nicole R. Buan

Department of Biochemistry: Faculty Publications

Microbial metabolism and trophic interactions between microbes give rise to complex multispecies communities in microbe-host systems. Bacteroides thetaiotaomicron (B. theta) is a human gut symbiont thought to play an important role in maintaining host health. Untargeted nuclear magnetic resonance metabolomics revealed B. theta secretes specific organic acids and amino acids in defined minimal medium. Physiological concentrations of acetate and formate found in the human intestinal tract were shown to cause dose-dependent changes in secretion of metabolites known to play roles in host nutrition and pathogenesis. While secretion fluxes varied, biomass yield was unchanged, suggesting feedback inhibition does not affect metabolic …

Development Of A Novel Highly-Sensitive Brucellosis Sensor Based On Surface Plasmon Resonance Spectroscopy, Amal Kasry, Ihab Adly, Asharf Sayour, Hossam Sayour

Nanotechnology Research Centre

Brucellosis is considered a significant health threat, it is an infectious disease caused by the bacteria Brucella, which can spread from animals to humans causing severe diseases. Through this project, we aim to develop a very highly sensitive biosensor to detect Brucella early before spreading. This sensor is based on surface plasmon resonance (SPR) technique, which is used to analyze kinetics of interaction between biomolecules. It can detect down to picomolar concentrations of some proteins.

Glycolic Acid Utilization In Two Species Of Marine Bacteria, Erik S. Timsak

STAR Program Research Presentations

Interactions between bacteria and phytoplankton are crucial for the cycling of organic matter in marine environments. Around 50% of organic carbon taken up by marine bacteria is converted into inorganic carbon. The uptake of organic carbon by marine bacteria exuded from phytoplankton is a key factor in regulating the marine carbon cycle. One such molecule that is exuded by phytoplankton and then uptaken by marine bacteria is called glycolate - the anion of glycolic acid, a two caron molecule. Glycolate is exuded by phytoplankton during photorespiration and 10-50% of dissolved organic carbon in marine environments is comprised of glycolate. Additionally, …

Structure/Function Analysis Of Fega And Fhua In Bradyrhizobium Sp., Alexander James Herd

Senior Honors Projects, 2010-2019

Bradyrhizobium japonicum is a Gram-negative soil bacterium commonly known for its agriculturally significant mutualistic relationship with soybean. In this symbiosis, the bacteria and plant undergo complex molecular signaling characterized by sent and received signals resulting in the formation of infection threads and root nodules. This research aimed to compare two related bacterial outer membrane proteins, FegA and FhuA, associated with the molecular signaling between the bacteria and plant. Previous work has led to the hypothesis that the N-terminal domain (NTD) of FegA in B. japonicum is needed for a functional symbiosis to occur. Recombinant bacterial strains expressing altered FegA proteins …

Research Of Sustainable Jet Fuel Production Using Microbes, Rajee Olaganathan

Publications

Global climate change, coupled with rapidly increasing oil prices and energy demand around the world, has paved a way for intense research in the biofuel sector. Stakeholders in the aviation industry have started to focus on bio-jet fuel. Bio-jet fuel is regarded as a sustainable solution to greenhouse gas emissions and energy demand. This paper provides a brief review of the biofuel production technologies, the role of bacteria in producing hydrocarbons and the recent advancements in microbial engineering to enhance the biofuel production. Finally, this paper concludes by highlighting the challenges and future research implications in bio-jet fuel production.

Survey Of Microbial Urea Degrader Diversity In Two Freshwater Ecosystems: Lake Shenandoah And The Shenandoah River, Naomi E. Gilbert

Senior Honors Projects, 2010-2019

One of the primary drivers of cyanobacterial harmful algal blooms (cHABs) in freshwater systems is nutrient loading, particularly of nitrogen and phosphorus. There has been an increased focus on assessing the role of nitrogen (N) in freshwater lakes and rivers that suffer cHABs. Urea, a widely-used, N-rich fertilizer, is a source of interest due to its abundance in freshwater ecosystems, primarily caused by anthropogenic nutrient loading. While recent work has shown that cHAB population succession may favor the toxic cyanobacterium Microcystis in urea-rich waters, the diversity of the associated bacterial community capable of degrading urea has yet to be determined. …

Optimizing Gdna Purification And Qpcr Techniques For Specific Detection And Enumeration Of Probiotic Bacteria, Katelynn C. Lee, Jennifer Vanderkelen, Christopher Kitts

STAR Program Research Presentations

Probiotics are live microorganisms, like bacteria and yeast, which are thought to provide health benefits when ingested. Large manufacturers produce blends of probiotics for supplementing the diets of agriculturally important animals. Commercial probiotic products are labeled with the number of cells present at the time of manufacture. Our assignment was to develop an assay which can be used to quantify the number of specific lactic acid bacteria present in certain probiotic products, thus verifying the number reported on the product labels. This quantification process involves isolating genomic DNA (gDNA) from the given samples and then running the DNA through a …

Optimization Of A Genomic Editing System Using Crispr/Cas9-Induced Site-Specific Gene Integration, Jillian L. Mccool Ms., Nick Hum, Gabriela G. Loots

STAR Program Research Presentations

The CRISPR-Cas system is an adaptive immune system found in bacteria which helps protect against the invasion of other microorganisms. This system induces double stranded breaks at precise genomic loci (1) in which repairs are initiated and insertions of a target are completed in the process. This mechanism can be used in eukaryotic cells in combination with sgRNAs (1) as a tool for genome editing. By using this CRISPR-Cas system, in addition to the “safe harbor locus,” ROSAβ26, the incorporation of a target gene into a site that is not susceptible to gene silencing effects can be achieved through few …

The Effect Of Transformed Escherichia Coli On The Mouse Intestine Microbiome: The Microbial Metabolic Enhancement Hypothesis, Bryar P. Kader

Senior Honors Theses

Metabolic disorders affect around thirty-four percent of the population in the United States. Among these disorders is lactose intolerance, which results from diminished production of the human lactase enzyme. This disorder and others like it are genetically determined and cannot be cured. However, the use of transformed bacteria implanted in the colon may provide a means by which the faulty pathway can be bypassed. To test whether transformed bacteria have the capability to aid in the digestion of normally indigestible compounds, a transformed strain of Escherichia coli overexpressing the beta-galactosidase enzyme encoded by the lacZ gene was colonized in the …

Anaerobic Detoxification Of Acetic Acid In A Thermophilic Ethanologen, A Joe Shaw, Bethany B. Miller, Stephen R. Rogers, William Robert Kenealy, Alex Meola, Ashwini Bhandiwad, W Ryan Sillers, Indraneel Shikhare, David Hogsett, Christopher Herring

Dartmouth Scholarship

The liberation of acetate from hemicellulose negatively impacts fermentations of cellulosic biomass, limiting the concentrations of substrate that can be effectively processed. Solvent-producing bacteria have the capacity to convert acetate to the less toxic product acetone, but to the best of our knowledge, this trait has not been transferred to an organism that produces ethanol at high yield. We have engineered a five-step metabolic pathway to convert acetic acid to acetone in the thermophilic anaerobe Thermoanaerobacterium saccharolyticum.

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Integrated Nanoscale Imaging And Spatial Recognition Of Biomolecules On Surfaces, Congzhou Wang

Theses and Dissertations

Biomolecules on cell surfaces play critical roles in diverse biological and physiological processes. However, conventional bulk scale techniques are unable to clarify the density and distribution of specific biomolecules in situ on single, living cell surfaces at the micro or nanoscale. In this work, a single cell analysis technique based on Atomic Force Microscopy (AFM) is developed to spatially identify biomolecules and characterize nanomechanical properties on single cell surfaces. The unique advantage of these AFM-based techniques lies in the ability to operate in situ (in a non-destructive fashion) and in real time, under physiological conditions or controlled micro-environments.

First, AFM-based …

Use Of Image Cytometry For Quantification Of Pathogenic Fungi In Association With Host Cells, Charlotte A. Berkes, Leo Li-Ying Chan, Alisha Wilkinson, Benjamin Paradis

Biology Faculty Publications

Studies of the cellular pathogenesis mechanisms of pathogenic yeasts such as Candida albicans, Histoplasma capsulatum, and Cryptococcus neoformans commonly employ infection of mammalian hosts or host cells (i.e. macrophages) followed by yeast quantification using colony forming unit analysis or flow cytometry. While colony forming unit enumeration has been the most commonly used method in the field, this technique has disadvantages and limitations, including slow growth of some fungal species on solid media and low and/or variable plating efficiencies, which is of particular concern when comparing growth of wild-type and mutant strains. Flow cytometry can provide rapid quantitative information regarding yeast …

Pcr Primers For The Detection Of Propane And Butane-Oxidizing Microorganisms, Brian Jeremy Chan

Master's Theses

In an increasingly energy-hungry world, our capacity to meet the heightened energy demands of the future has become a pressing matter. The most urgent of these concerns are tied to the accessibility of petroleum. Various experts have proselytized both the imminent arrival of peak oil production rates and the ensuing decline of those rates thereafter. And to that end, the development of novel and advanced oil exploration methodologies has become almost as important as finding the sources of oil themselves.

The soils above petroleum reservoirs play host to various communities of alkane- oxidizing bacteria that can utilize the natural gas …

Development Of Pyrf-Based Genetic System For Targeted Gene Deletion In Clostridium Thermocellum And Creation Of A Pta Mutant, Shital A. Tripathi, Daniel G. Olson, D. Aaron Argyros, Bethany B. Miller, Trisha F. Barrett, Daniel M. Murphy, Jesse D. Mccool, Anne K. Warner, Vineet B. Rajgarhia, Lee R. Lynd, David A. Hogsett, Nicky C. Caiazza

Dartmouth Scholarship

We report development of a genetic system for making targeted gene knockouts in Clostridium thermocellum, a thermophilic anaerobic bacterium that rapidly solubilizes cellulose. A toxic uracil analog, 5-fluoroorotic acid (5-FOA), was used to select for deletion of the pyrF gene. The ΔpyrF strain is a uracil auxotroph that could be restored to a prototroph via ectopic expression of pyrF from a plasmid, providing a positive genetic selection. Furthermore, 5-FOA was used to select against plasmid-expressed pyrF, creating a negative selection for plasmid loss. This technology was used to delete a gene involved in organic acid production, namely pta, which encodes …

Metal-Resistance Genetically Engineered Bacteria, Sylvia Daunert, Donna Scott, Sridhar Ramanathan

KWRRI Research Reports

Bacterial-based electrochemical and optical sensing systems that respond in a highly selective and sensitive manner to antimonite and arsenite have been developed. This was accomplished by using genetically engineered bacteria bearing one of two plasmids constructed for our studies. The first plasmid, pBGD23, contains the operator/promoter region (O/P) and the gene of the ArsR protein from the ars operon upstream from the β-galactosidase gene. In the absence of antimonite/arsenite, ArsR binds to the 0/P site and prevents the transcription of the genes for ArsR and β-galactosidase, thus blocking expression of these proteins. When antimonite or arsenite is present in the …