Biochemistry Commons^™

Novel Approaches To Mitigating Bacterial Biofilm Formation And Intercellular Communication, Stephen Kasper

Legacy Theses & Dissertations (2009 - 2024)

Long thought of as solitary single-cell organisms, it is now widely accepted that bacteria can act and cooperate as social organisms. Phenomena such as biofilm formation and quorum sensing (QS) are two intimately intertwined cooperative behaviors that significantly contribute to the pathogenesis of many bacteria. Biofilms are surface associated communities of bacteria encased in a secreted extracellular matrix, which provides several advantages over an individualized lifestyle, such as increased protection from antimicrobial agents as well as enhanced opportunity for the exchange of genetic material. Bacterial QS is a system of population-based communication through the production, sensing, and response to chemical …

Multifunctional Nanomaterials Utilizing Hybridization Chain Reaction For Molecular Diagnostics And Bioanalytical Applications, Md Muhit Rana

Legacy Theses & Dissertations (2009 - 2024)

DNA nanotechnology has shown great promise in molecular diagnostic, bioanalytical and biomedical applications. The great challenge of detecting target analytes, biomarkers and small molecules, in molecular diagnostics is low yield sensitivity. To address this challenge, different nanomaterials have been used for a long time and to date there is no such cost-effective bioanalytical technique which can detect these target biomarkers (DNA, RNA, circulating DNA/miRNA) or environmental heavy metal ions (Hg2+ and Ag+) in a cost-effective and efficient manner.

Toward Biochemical Conversion Of Lignocellulose On-Farm: Pretreatment And Hydrolysis Of Corn Stover In Situ, Alicia A. Modenbach, Sue E. Nokes, Michael D. Montross, Barbara L. Knutson

Biosystems and Agricultural Engineering Faculty Publications

High-solids lignocellulosic pretreatment using NaOH followed by high-solids enzymatic hydrolysis was evaluated for an on-farm biochemical conversion process. Increasing the solids loadings for these processes has the potential for increasing glucose concentrations and downstream ethanol production; however, sequential processing at high-solids loading similar to an on-farm cellulose conversion system has not been studied. This research quantified the effects of high-solids pretreatment with NaOH and subsequent high-solids enzymatic hydrolysis on cellulose conversion. As expected, conversion efficiency was reduced; however, the highest glucose concentration (40.2 g L^-1), and therefore the highest potential ethanol concentration, resulted from the high-solids combined pretreatment …

Enzymatically Active Microspheres For Self-Propelled Colloidal Engines, Jungeun Park

Dissertations and Theses

Micro- and nano-motors have attracted numerous attentions from various scientific areas due to their potential applications. Most studies on self-propelled colloidal engines have exploited catalytic decomposition of hydrogen peroxide to drive the motor. Since the hydrogen peroxide is caustic, it is not suitable to use in biological applications, encouraging people to develop “greener” fuels. The aim of this research is to study a new transduction mechanism for self-propulsion not tied to hydrogen peroxide, and which can in particular be used with biological molecules as fuels. In this study, we focus on making particles with enzymatic activity which can effectively decompose …

Biochemical And Histological Differences Between Costal And Articular Cartilages, Michael W. Stacey

Bioelectrics Publications

Biologically, costal cartilage is an understudied tissue type and much is yet to be learned regarding underlying mechanisms related to form and function, and how these relate to disease states, specifically chest wall deformity. Chest wall deformities have a component of inheritance, implying underlying genetic causes; however the complexity of inheritance suggests multiple genetic components. At our Centre investigations were performed on gene expression of key select genes from costal cartilage removed at surgery of patients with chest wall deformity to show high expression of decorin, a key player in collagen fiber formation and growth. Also, the degree of tissue …

Comparing An Atomic Model Or Structure To A Corresponding Cryo-Electron Microscopy Image At The Central Axis Of A Helix, Stephanie Zeil, Julio Kovacs, Willy Wriggers, Jing He

Computer Science Faculty Publications

Three-dimensional density maps of biological specimens from cryo-electron microscopy (cryo-EM) can be interpreted in the form of atomic models that are modeled into the density, or they can be compared to known atomic structures. When the central axis of a helix is detectable in a cryo-EM density map, it is possible to quantify the agreement between this central axis and a central axis calculated from the atomic model or structure. We propose a novel arc-length association method to compare the two axes reliably. This method was applied to 79 helices in simulated density maps and six case studies using cryo-EM …

Sugarcane Bagasse Hydrolysis Enhancement Using Bsa, Antonio Carlos Freitas Dos Santos

Open Access Theses

Lignocellulose is composed of polysaccharides linked to lignin and other aromatic compounds, making the sugars not readily available to fermentation. This entails that biomass must go through the unit operations of pretreatment and enzyme hydrolysis. Pretreatment opens the structure to allow the enzymes to act on and hydrolyze cellulose and hemicellulose to glucose and/or xylose which in turn are fermented to ethanol. Concomitantly, the enzymes interact with soluble phenols and insoluble solids derived from lignin that inhibit hydrolysis. This leads to high enzyme loadings and higher production costs. Soluble phenols can be eliminated through washing. Insoluble lignin, however, demands another …

Membrane Chromatography For Bioseparations: Ligand Design And Optimization, Zizhao Liu

Graduate Theses and Dissertations

Membrane chromatography, or membrane adsorber, represents an attractive alternative to conventional packed bed chromatography used in downstream processing. Membrane chromatography has many advantages, including high productivity, low buffer consumption and ease to scale up. This doctoral dissertation focuses on developing novel polymeric ligands for protein separations using membrane chromatography. Atom transfer radical polymerization (ATRP), known as a controlled radical polymerization technique, has been used to control the architecture of grafted polymeric ligands. The center theme of this dissertation is to develop new polymeric ligands and investigate how the polymer’s property (e.g. flexibility, hydrophobicity) and architecture (e.g. chain density, chain length) …

Conformationally Superarmed S-Ethyl Glycosyl Donors As Effective Building Blocks For Chemoselective Oligosaccharide Synthesis In One Pot, Mithila Bandara, Jagodige Yasomanee, Nigam Rath, Christian Pedersen, Mikael Bols, Alexei Demchenko

Chemistry & Biochemistry Faculty Works

A new series of superarmed glycosyl donors has been investigated. It was demonstrated that the S-ethyl leaving group allows for high reactivity, which is much higher than that of equally equipped S-phenyl glycosyl donors that were previously investigated by our groups. The superarmed S-ethyl glycosyl donors equipped with a 2-O-benzoyl group gave complete β-stereoselectivity. Utility of the new glycosyl donors has been demonstrated in a one-pot one-addition oligosaccharide synthesis with all of the reaction components present from the beginning.

Development Of In Vivo Systems For Detecting And Studying Ribosome Inhibition By Small Molecules, Shijie Huang

Chemistry and Chemical Biology ETDs

The ribosome is the quintessential antibacterial drug target, with many structurally and mechanistically distinct classes of antibacterial agents acting by inhibiting ribosome function. Detecting and quantifying ribosome inhibition by small molecules and investigating their binding modes and mechanisms of action are critical to antibacterial drug discovery and development efforts. To develop a ribosome inhibition assay that is operationally simple, yet provides direct information on the drug target and the mechanism of action, we have developed engineered E. coli strains harboring an orthogonal ribosome controlled green fluorescent protein reporter that produce fluorescent signal when the O-ribosome is inhibited. As a proof …

Nanobubbles Provide Theranostic Relief To Cancer Hypoxia, Christopher M. Long, Pushpak N. Bhandari, Joseph Irudayaraj

The Summer Undergraduate Research Fellowship (SURF) Symposium

Hypoxia is a common motif among tumors, contributing to metastasis, angiogenesis, cellular epigenetic abnormality, and resistance to cancer therapy. Hypoxia also plays a pivotal role in oncological studies, where it can be used as a principal target for new anti-cancer therapeutic methods. Oxygen nanobubbles were designed in an effort to target the hypoxic tumor regions, thus interrupting the hypoxia-inducible factor-1α (HIF-1α) regulatory pathway and inhibiting tumor progression. At less than 100nm, oxygen nanobubbles act as a vehicle for site-specific oxygen delivery, while also serving as an ultrasound contrast agent for advanced imaging purposes. Through in vitro and in vivo studies, …

Role Of Sumoylation In Mitochondrial Division In Tetrahymena Thermophila, Ramya Modi, James Forney

The Summer Undergraduate Research Fellowship (SURF) Symposium

SUMOylation is a post translation modification that involves the addition of a small protein called SUMO, Small Ubiquitin-like MOdifier to a target protein. It is an important mechanism for the regulation of gene expression, the maintenance of genomic stability and in modifying nuclear proteins. More recently evidence has emerged for its importance in regulating mitochondrial fission and fusion in mammalian cells. This study evaluates the parameters for optimal staining of Tetrahymena thermophila mitochondria using two different dyes and then examines different cell lines with defects in the SUMOylation pathway. The first staining method uses Mitotracker Green, a vital stain that …

Enhancing Silymarin Fractionation Via Molecular Modeling Using The Conductor-Like Screening Model For Real Solvents, Emma C. Brace

Open Access Theses

The market for bio-based products from plant sources is on the rise. There is a global challenge to implement environmentally clean practices for the production of fuels and pharmaceuticals from sustainable resources. A significant hurdle for discovery of comparable plant-derived products is the extensive volume of trial-and-error experimentation required. To alleviate the experimental burden, a quantum mechanics based molecular modeling approach known as the COnductor-like Screening Model for Real Solvents (COSMO-RS) was used to predict the best biphasic solvent system to purify silymarins from an aqueous mixture. Silymarins are a class of flavonolignans present in milk thistle ( Silybum marianum …

Tunable Nano-Delivery System For Cancer Treatment: A New Approach For Targeted Localized Drug Delivery, Rana Falahat

USF Tampa Graduate Theses and Dissertations

Localized drug delivery systems have been widely studied as potential replacements for conventional chemotherapy with the capability of providing sustained and controlled drug release in specific targeted sites. They offer numerous benefits over conventional chemotherapy such as enhancing the stability of embedded drugs and preserving their anticancer activity, providing sustained and controlled drug release in the tumor site, reducing toxicity and diminishing subsequent side effects, minimizing the drug loss, averting the need for frequent administrations, and minimizing the cost of therapy.

The aim of this study is to develop a localized drug delivery system with niosomes embedded in a chitosan …

Hiv Vaccines: Progress, Limitations And A Crispr/Cas9 Vaccine, Omar A. Garcia Martinez

Biology: Student Scholarship & Creative Works

ABSTRACT: The HIV-1 pandemic continues to thrive due to ineffective HIV-1 vaccines. Historically, the world’s most infectious diseases, such as polio and smallpox, have been eradicated or have come close to eradication due to the advent of effective vaccines. Highly active antiretroviral therapy is able to delay the onset of AIDS but can neither rid the body of HIV-1 proviral DNA nor prevent further transmission. A prophylactic vaccine that prevents the various mechanisms HIV-1 has to evade and attack our immune system is needed to end the HIV-1 pandemic. Recent advances in engineered nuclease systems, like the CRISPR/Cas9 system, have …

Thermodynamics And Kinetics Of The Three-Way Junction Of Phi29 Motor Prna And Its Assembly Into Nanoparticles For Therapeutic Delivery To Prostate Cancer, Daniel W. Binzel

Theses and Dissertations--Pharmacy

The emerging field of RNA nanotechnology necessitates creation of functional RNA nanoparticles, but has been limited by particle instability. Previously, it was found the three-way junction (3WJ) of the Phi29 DNA packaging motor pRNA was found to be ultra-stable and assemble in solution without the presence of metal ions. The three-way junction is composed of three short oligo RNA strands and proven to be thermodynamically stable. Here the assembly mechanism, thermodynamic and enzymatic stabilities, and kinetics are examined in order to understand the stability behind this unique motif. Thermodynamic and kinetics studies found that the pRNA 3WJ formed out of …

Investigation Of Enzymatically Synthesized Glycogen As A Novel Nanodendrimer For Therapeutic Delivery, Sarah Ann Engelberth

Legacy Theses & Dissertations (2009 - 2024)

The field of medicinal chemistry is ever expanding, designing and discovering new therapeutic strategies. Oftentimes, it is challenging for these therapeutics to undergo clinical translation due to ineffective administration or unwanted toxicity in vivo. As such, drug delivery vehicles are designed to overcome these hurdles, allowing for delivery to the site of action by improving biodistribution, protecting therapeutic cargo, and decreasing toxicity. The work presented here aims to investigate a naturally-derived carbohydrate nanodendrimer, enzymatically synthesized glycogen (ESG) for drug delivery. This nontoxic, highly-branched, glucose-based structure has interior void volumes to allow for cargo encapsulation as well as a large density …

The Gammaturc Nanomachine Mechanism And Future Applications, Timothy Riehlman

Legacy Theses & Dissertations (2009 - 2024)

The complexity and precision of the eukaryotic cell’s cytoskeletal network is unrivaled by any man-made systems, perfected by billions of years of evolution, mastering elegant processes of self-assembly, error correction, and self-repair. Understanding the capabilities of these networks will have important and far reaching applications in human medicine by aiding our understanding of developmental processes, cellular division, and disease mechanisms, and through biomimicry will provide insights for biosynthetic manufacturing at the nanoscale and across scales. My research utilizes cross species techniques from Human to the model organism of Fission Yeast to investigate the structure and mechanisms of the g-tubulin ring …

Effects Of High Voltage Nanosecond Electric Pulses On Eukaryotic Cells (In Vitro): A Systematic Review, Tina Batista Napotink, Matej Reberšek, P. Thomas Vernier, Babara Mali, Damijan Miklavčič

Bioelectrics Publications

For this systematic review, 203 published reports on effects of electroporation using nanosecond high-voltage electric pulses (nsEP) on eukaryotic cells (human, animal, plant) in vitro were analyzed. A field synopsis summarizes current published data in the field with respect to publication year, cell types, exposure configuration, and pulse duration. Published data were analyzed for effects observed in eight main target areas (plasma membrane, intracellular, apoptosis, calcium level and distribution, survival, nucleus, mitochondria, stress) and an additional 107 detailed outcomes. We statistically analyzed effects of nsEP with respect to three pulse duration groups: A: 1–10 ns, B: 11–100 ns and C: …

Quantitative Comparison Of A Nanoengineered Alumina Coated Cnt Arrays To Sio2 Coated Cnts And Solution Based Delivery System, Shree Aier

Maseeh Summer Undergraduate Research Experience

To meet the growing need for nanoengineered biocompatible materials to serve as drug delivery platforms, in this research, carbon nanotube arrays were fabricated by chemical vapor deposition, followed by an alumina coating by the high yielding, tightly controlled atomic layer deposition. This nanoengineered vertically aligned alumina nanowire array serves as a platform for delivering antigens, which act as cancer adjuvants. The physicochemical characteristics of the nanowires (NWs) can significantly influence the delivery of a biomolecule to immune cells. To investigate the material characteristics, the delivery efficiency of the antigen using NWs was quantitatively assessed by flow cytometry. Further, the mechanism …

Investigation Of The Inherent Chemical, Structural, And Mechanical Attributes Of Bio-Engineered Composites Found In Nature: Alligator Gar’S Exoskeleton Fish Scales, Wayne Derald Hodo

Graduate Theses and Dissertations

The U.S. Army has determined a huge cost savings of up to 51% can be accomplished by reducing the gross vehicle weight, for their personnel carrier, by 33%. To cut cost, composite materials are needed. Man-made composites can have superior material properties (high-strength, high-fracture toughness, and lightweight), but they are prone to delamination at the glued-layered interface. In contrast, fish scale is a natural composite that has the same material properties and, additionally, tend not to delaminate.

The focus of this study was to learn how nature integrates hard and soft materials at each length scale to form a layered …

Production And Harvest Of Microalgae In Wastewater Raceways With Resource Recycling, Alexander Colin Roberts

Master's Theses

Microalgae can be grown on municipal wastewater media to both treat the wastewater and produce feedstock for algae biofuel production. However the reliability of treatment must be demonstrated, as well as high areal algae productivity on recycled wastewater media and efficient sedimentation harvesting. This processes was studied at pilot scale in the present research.

A pilot facility was operated with nine CO₂-supplemented raceway ponds, each with a 33-m² surface area and a 0.3-m depth, continuously from March 6, 2013 through September 24, 2014. The ponds were operated as three sets of triplicates with two sets continuously fed …

Heterogeneous Oxidation Of Catechol, Elizabeth A. Pillar, Ruixin Zhou, Marcelo I. Guzman

Chemistry Faculty Publications

Natural and anthropogenic emissions of aromatic hydrocarbons from biomass burning, agro-industrial settings, and fossil fuel combustion contribute precursors to secondary aerosol formation (SOA). How these compounds are processed under humid tropospheric conditions is the focus of current attention to understand their environmental fate. This work shows how catechol thin films, a model for oxygenated aromatic hydrocarbons present in biomass burning and combustion aerosols, undergo heterogeneous oxidation at the air–solid interface under variable relative humidity (RH = 0–90%). The maximum reactive uptake coefficient of O₃(g) by catechol γ_O3 = (7.49 ± 0.35) × 10^–6 occurs for …

A Novel Synthetic Yeast For Enzymatic Biodigester Pretreatment, Tianyu Tan, Mark S. Aronson, Arren Liu, Jill H. Osterhus, Melissa Robins, Suraj Mohan, Erich Leazer, Bowman Clark, Alexa Petrucciani, Katherine Lowery, James Welch, Casey Martin, Helena Lysandrou, Michael E. Scharf, Jenna Rickus

The Summer Undergraduate Research Fellowship (SURF) Symposium

Lignin, a complex organic polymer, is a major roadblock to the efficiency of biofuel conversion as it both physically blocks carbohydrate substrates and poisons biomass degrading enzymes, even if broken down to monomer units. A pretreatment process is often applied to separate the lignin from biomass prior to biofuel conversion. However, contemporary methods of pretreatment require large amounts of energy, which may be economically uncompelling or unfeasible. Taking inspiration from several genes that have been isolated from termites and fungi which translate to enzymes that degrade lignin, we want to establish a novel “enzymatic pretreatment” system where microbes secrete these …

Viewing The Extracellular Matrix: An Imaging Method For Tissue Engineering, Michael Drakopoulos, Sarah Calve

The Summer Undergraduate Research Fellowship (SURF) Symposium

The field of regenerative medicine seeks to create replacement tissues and organs, both to repair deficiencies in biological function and to treat structural damage caused by injury. Scaffoldings mimicking extracellular matrix (ECM), the structure to which cells attach to form tissues, have been developed from synthetic polymers and also been prepared by decellularizing adult tissue. However, the structure of ECM undergoes significant remodeling during natural tissue repair, suggesting that ECM-replacement constructs that mirror developing tissues may promote better regeneration than those modeled on adult tissues. This work investigated the effectiveness of a method of viewing the extracellular matrix of developing …

Using Peptoids To Build Robust, Efficient Microarray Systems, Dhaval Sunil Shah

Graduate Theses and Dissertations

Recent studies have shown microarrays to be indispensable for various biological applications, allowing for high-throughput processing and screening of biological samples such as RNA, DNA, proteins and peptides using a small sample volume (< 1 µL). Peptoids (poly-N-substituted glycine oligomers) can be used as a substitute for antibodies as capture molecules, as well as coatings for slides in antibody microarrays. The ease of synthesis of peptoids, high customizability with desired bioactivity, and speed of synthesis allows us to build a diagnostic system with a large dynamic range that can detect biomolecules from a minimal sample size. In this study, peptoid-based antibody mimics are designed to have both structural and functional features similar to those of antibodies, including a stable constant region (scaffolding) and a variable region for protein recognition. Peptoids previously screened via combinatorial library synthesis to be specific to bind Mdm-2 (mouse double minute 2 homolog) and GST (gluthathione S-transferase), have been synthesized. The protein recognition peptoids have been conjugated to PEG (polyethylene glycol) molecules with modified end groups; an amine group on one end that allows for immobilization and orientation on the slide, and an azide group on the other end that will allow for attachment to the peptoid through “click chemistry”. The number of capture molecules printed on the slides can be increased by making the available surface area of the slide larger via coating with microspheres. We have determined that partially water soluble peptoids that are also helical, can self-assemble into microspheres. Sequences have been developed that can consistently produce uniform microsphere coatings on slides that increase the overall surface area. A high surface area corresponds to a higher number of binding sites, and therefore a more sensitive system. The work done has shown that slides may be successfully coated in order to potentially improve the detection system.

Three-Dimensional Ideal Gas Reference State Based Energy Function, Avdesh Mishra

LSU New Orleans Theses and Dissertations

Energy functions are found to be a key of protein structure prediction. In this work, we propose a novel 3-dimensional energy function based on hydrophobic-hydrophilic properties of amino acid where we consider at least three different possible interaction of amino acid in a 3-dimensional sphere categorized as hydrophilic versus hydrophilic, hydrophobic versus hydrophobic and hydrophobic versus hydrophilic. Each of these interactions are governed by a 3-dimensional parameter alpha used to model the interaction and 3-dimensional parameter beta used to model weight of contribution. We use Genetic Algorithm (GA) to optimize the value of alpha, beta and Z-score. We obtain three …

Biofilm-Related Materials As Total N-Nitrosamine (Tono) Precursors And Hydroxylamine-Based Interferences In Tono And N-Nitrosodimethylamine (Ndma) Measurements, David Allen Meints

Graduate Theses and Dissertations

In this study, a chemiluminescence-based total N-nitrosamine (TONO) assay was adapted to include a solid-phase extraction (SPE) step to assess the role of biologically derived materials as N-nitrosamine precursors. Methanol was determined to be a suitable solvent for the SPE-TONO assay, with N-nitrosodimethylamine (NDMA) losses estimated to be 30% by SPE alone and an additional 15% from concentration of the methanol extracts by N2-gas blowdown. Three biofilm-derived materials - poly-N-acetylglucosamine (PNAG), Pseudomonas aeruginosa, and tryptophan - were individually chloraminated and dose-response relationships were observed with the SPE-TONO assay, indicating biofilm are potential N-nitrosamine precursors. The role of hydroxylamine - a …

Selection Methods For Genetically-Modified T Cells: In Support Of Translational Therapy, David Rushworth

Dissertations and Theses (Open Access)

T cells are blood cells which organize the immune system of the host. These cells are necessary for the host to respond appropriately to threats from foreign organisms and cancerous growth. However, in the case of certain infections and cancer, T cells are unable to respond appropriately to a threat and establish immunity. This leads to disease when the infection or cancer is not sufficiently eliminated. On the other hand, T cells can lack tolerance for healthy tissue and perceive healthy tissue as infected. The ensuing over-reactive immune response also leads to disease. A delicate balance must exist between immunity …

In Vivo Near Ir Fluorescent Imaging Of Hollow Polymeric Nanocapsules, Venkata Suresh Patthipati

Biological Sciences Theses & Dissertations

Medical Imaging has been an integral component in medical diagnosis and therapeutics. It is frequently used in conjunction with other treatment modalities and has been used for developing applications that range from cancer management to clinical practice. Nanotechnology and its applications are foreseen to have a profound impact on life sciences. Nanomaterial based imaging has a significant potential in addressing medical challenges such as tumor localization, targeted delivery of drugs and real time diagnosis and management of circulation pathology. In particular, polymer based nanoparticles are increasingly being developed as they can be customized according to the diagnostic and/or therapeutic requirements. …