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Exploration Of Thiol-Michael Addition Bioconjugation To Extend Polymers Of A Protein-Based Hydrogel, Elaine Wallin Smith 2019 University of Mississippi

Exploration Of Thiol-Michael Addition Bioconjugation To Extend Polymers Of A Protein-Based Hydrogel, Elaine Wallin Smith

Honors Theses

Hydrogels have been explored for many biomedical applications, including targeted, in situ drug delivery to avoid the negative side effects associated with systemic delivery. In our work, we are exploiting the high affinity, calcium-dependent binding between calmodulin and its target peptides to create a biomaterial for in situ, extracellular drug delivery. Genes were engineered to make two protomers, Calmodulin Collagen-Like Protein (CCLP) and Peptide Collagen-Like Protein (PCLP), that will spontaneously self-assemble in situ due to the high Ca2+ concentration in the extracellular space and provide tunable, targeted drug delivery in a biocompatible hydrogel. One important factor that would dictate the …


Benchmark Structures And Harmonic Vibrational Frequencies Of Hydrated Halide Ions: X– (H2o)N, X = F, Cl, Br, And I (Where N = 1 – 4), Caroline Anne Rader 2019 University of Mississippi

Benchmark Structures And Harmonic Vibrational Frequencies Of Hydrated Halide Ions: X– (H2o)N, X = F, Cl, Br, And I (Where N = 1 – 4), Caroline Anne Rader

Honors Theses

This study extends our efforts to generate benchmark structures and harmonic vi- brational frequencies from neutral hydrogen bonded clusters to solvated ions. The analytical gradients and Hessians developed for the N-body:Many-body integrated QM:QM method facilitate the computation of benchmark-quality properties near the CCSD(T) complete basis set limit. In this work, a series of solvated halide ion sys- tems (X−(H2O)n clusters, where X = F, Cl, Br and I and n = 1 to 4) is being characterized with the MP2 and 2-body:Many-body CCSD(T):MP2 (2b:Mb) meth- ods. For n ≥ 2, the latter technique uses the high-level CCSD(T) method to evaluate …


Time- And Ph- Dependent Proteolysis Of Engineered Proteins By Collagenase, Hunter Berry 2019 University of Mississippi

Time- And Ph- Dependent Proteolysis Of Engineered Proteins By Collagenase, Hunter Berry

Honors Theses

Pleiotropic effects from oral administration of anti-inflammatory drugs limit their effectiveness. The ultimate goal of this project is to develop a novel self-assembling protein-based hydrogel for in situ delivery of NSAIDs at the site of chronic inflammation. Since inflammation causes acidification and activation of collagenases in the inflamed tissue, we have designed the hydrogel to respond to both of these queues to effectively deliver drug at the site. Self-assembly of the protein hydrogel exploits the high affinity and specific interaction between the protein calmodulin (CaM) and its specific binding peptide, M13. The two components of the hydrogel, CCLP and PCLP …


Determining The Role Of Nudt7 In The Regulation Of Cellular Coa Levels And Metabolism, Stephanie Anne Shumar 2019 West Virginia University

Determining The Role Of Nudt7 In The Regulation Of Cellular Coa Levels And Metabolism, Stephanie Anne Shumar

Graduate Theses, Dissertations, and Problem Reports (ETD)

Coenzyme A (CoA) is an essential cofactor required for hundreds of metabolic processes. Because it is such a critical cofactor, CoA levels are tightly regulated. In the fasted state and in diabetic mice, the concentration of CoA increases dramatically in the liver. This phenotype is associated with constitutively low CoA degradation, a process that is emerging as a potentially important mechanism for CoA regulation. Nudt7 and Nudt19 are two mammalian peroxisomal enzymes with CoA-degrading activity, which are highly expressed in the liver and kidney, respectively. Limited information is available on the biochemistry of Nudt7 and Nudt19; the structural basis for …


Adaptation Of The Streptococcal Collagen-Like Protein 1, Scl1, Of Group A Streptococcus To Recognize Fibronectin Type Iii Repeats, Dudley H. Mcnitt 2019 West Virginia University

Adaptation Of The Streptococcal Collagen-Like Protein 1, Scl1, Of Group A Streptococcus To Recognize Fibronectin Type Iii Repeats, Dudley H. Mcnitt

Graduate Theses, Dissertations, and Problem Reports (ETD)

Background: Group A Streptococcus (GAS) is responsible more than 700 million infections worldwide each year. Most of these infections start with initial colonization of the throat and skin, which is augmented by surface adhesins. The streptococcal collagen-like protein 1 (Scl1) is a major adhesin expressed by GAS that contains an N-terminal sequence-variable (V) domain, protruded away from the cell surface by the collagen domain. The Scl-V domain is comprised of three pairs of anti-parallel α-helices interconnected by surface-exposed loops. For attachment, GAS adhesins require a portal of entry, such as a wound or breach in the epithelium, to enter …


Immunomagnetic Beads Coupled With Anti-Ph-20 Antibodies To Isolate Sperm From Dna Mixtures For Sexual Assault Kit Application, Kayla Becks 2019 West Virginia University

Immunomagnetic Beads Coupled With Anti-Ph-20 Antibodies To Isolate Sperm From Dna Mixtures For Sexual Assault Kit Application, Kayla Becks

Graduate Theses, Dissertations, and Problem Reports (ETD)

Sexual Assault Kits (SAKs) account for a large portion of DNA mixture samples that are processed within a forensic laboratory, most commonly in the form of vaginal swabs. A typical vaginal swab from a SAK contains the female victim's epithelial cells and varying concentrations of sperm cells left by the perpetrator. The key to analyzing these types of samples is to separate the mixture into male and female fractions. As such, there is a demand to develop novel techniques that have the capability of recovering as much of the male fraction as possible, specifically in cases where there is a …


Tumor-Targeted Conjugated Polymer Nanoparticles With Encapsulated Iron And Its Biomedical Application For In Vitro Killing Of Melanoma Cell Lines Through Ferroptosis Assisted Chemodynamic Therapy (Cdt), Khalaf Jasim 2019 University of Central Florida

Tumor-Targeted Conjugated Polymer Nanoparticles With Encapsulated Iron And Its Biomedical Application For In Vitro Killing Of Melanoma Cell Lines Through Ferroptosis Assisted Chemodynamic Therapy (Cdt), Khalaf Jasim

Electronic Theses and Dissertations

Melanoma represents one of the most aggressive and lethal forms of skin cancer, with annually rising incidences throughout the world. Although chemotherapy modalities remain the mainstay of treatment, the therapeutic potential of chemotherapy typically is hampered by multidrug resistance (MDR) and nonspecific drug distribution that causes side-effects. To surmount such limitations, novel nanoformulations of low band-gap poly ({4,8-bis [(2-ethylhexyl) oxy] benzo [1,2-b:4,5-b?] dithiophene-2,6-diyl}{3-fluoro-2-[(2-ethylhexyl) carbonyl] thieno [3,4-b] thiophenediyl}) (PTB7) and poly [2,1,3-benzothiadiazole- 4,7- diyl [4,4-bis (2-ethylhexyl)- 4H-cyclopenta [2,1-b:3,4-b'] dithiophene-2,6-diyl]] (PCPDTBT) were fabricated by a reprecipitation method. These conjugated polymer nanoparticles were functionalized with the polypeptide endothelin-3 (EDN3-CPNPs) to target melanoma. The …


Studies Of Oxidative Damage, Brain Proteome, And Neurochemical Metabolites In Cognitive And Neurodegenerative Disorders: (1) Chemotherapy-Induced Cognitive Impairment; (2) Parkinson Disease Rat Model, Xiaojia Ren 2019 University of Kentucky

Studies Of Oxidative Damage, Brain Proteome, And Neurochemical Metabolites In Cognitive And Neurodegenerative Disorders: (1) Chemotherapy-Induced Cognitive Impairment; (2) Parkinson Disease Rat Model, Xiaojia Ren

Theses and Dissertations--Chemistry

The rate of cancer patients is increasing as the development of science and technology. Twenty million cancer survivors are estimated living in the United States by 2025. However, many cancer survivors show cognitive dysfunction, negatively affecting the quality of life. These cognitive impairments are recognized as chemotherapy-induced cognitive impairment (CICI), also called "chemo brain" by cancer survivors, including the diminished ability of memory and learning, hard to concentrate and focus, as well as diminution of executive function and processing speed. The etiologies and pathologies of CICI are complicated, especially in most cases the anti-cancer drug cannot cross the blood-brain barrier …


Investigation Of Amyloid Β Oligomer Dissociation Mechanisms By Single Molecule Fluorescence Techniques, Hope Cook Abdalla 2019 University of Kentucky

Investigation Of Amyloid Β Oligomer Dissociation Mechanisms By Single Molecule Fluorescence Techniques, Hope Cook Abdalla

Theses and Dissertations--Chemistry

Alzheimer’s disease (AD) is currently considered the most prevalent neurodegenerative disease and places a large financial burden on society as healthcare resources are limited and the disease does not have a cure. Alzheimer’s disease is characterized by the presence of amyloid beta (Aβ) plaques and neurofibrillary tangles; however current literature suggests Aβ oligomers are the main aggregating species leading to AD symptoms. Therefore, the underlying cause of Alzheimer’s, accumulation of amyloid beta, is currently being studied in hopes of developing treatment options. Our research aims at determining the mechanism and kinetics of Aβ oligomer dissociation into non-toxic monomers in the …


Impact Of Conformational Change, Solvation Environment, And Post-Translational Modification On Desulfurization Enzyme 2'-Hydroxybiphenyl-2-Sulfinate Desulfinase (Dszb) Stability And Activity, Landon C. Mills 2019 University of Kentucky

Impact Of Conformational Change, Solvation Environment, And Post-Translational Modification On Desulfurization Enzyme 2'-Hydroxybiphenyl-2-Sulfinate Desulfinase (Dszb) Stability And Activity, Landon C. Mills

Theses and Dissertations--Chemical and Materials Engineering

Naturally occurring enzymatic pathways enable highly specific, rapid thiophenic sulfur cleavage occurring at ambient temperature and pressure, which may be harnessed for the desulfurization of petroleum-based fuel. One pathway found in bacteria is a four-step catabolic pathway (the 4S pathway) converting dibenzothiophene (DBT), a common crude oil contaminant, into 2-hydroxybiphenyl (HBP) without disrupting the carbon-carbon bonds. 2’-Hydroxybiphenyl-2-sulfinate desulfinase (DszB), the rate-limiting enzyme in the enzyme cascade, is capable of selectively cleaving carbon-sulfur bonds. Accordingly, understanding the molecular mechanisms of DszB activity may enable development of the cascade as industrial biotechnology. Based on crystallographic evidence, we hypothesized that DszB …


Illuminating Dna Packaging In Sperm Chromatin: How Polycation Lengths, Underprotamination And Disulfide Linkages Alters Dna Condensation And Stability, Daniel Kirchhoff 2019 University of Kentucky

Illuminating Dna Packaging In Sperm Chromatin: How Polycation Lengths, Underprotamination And Disulfide Linkages Alters Dna Condensation And Stability, Daniel Kirchhoff

Theses and Dissertations--Chemistry

During spermiogenesis, somatic chromatin is remodeled and a vast majority (> 90%) of DNA histones are replaced by short arginine-rich peptides called protamines. This compaction is immense, with protamine-DNA self-assembly in sperm chromatin resulting in a final volume roughly 1/6th of a somatic nucleus. This near crystalline organization of the DNA in sperm is thought crucial both for the transport of the paternal genes as well as for the protection of genetic information as sperm chromatin is transcriptionally inactive and all DNA repair mechanisms are shut down.

Chapter 1 will include an overview of the topics discussed in this document, …


Multi-Scale Computational Studies Of Calcium (Ca2+) Signaling, Bin Sun 2019 University of Kentucky

Multi-Scale Computational Studies Of Calcium (Ca2+) Signaling, Bin Sun

Theses and Dissertations--Chemistry

Ca2+ is an important messenger that affects almost all cellular processes. Ca2+ signaling involves events that happen at various time-scales such as Ca2+ diffusion, trans-membrane Ca2+ transport and Ca2+-mediated protein-protein interactions. In this work, we utilized multi-scale computational methods to quantitatively characterize Ca2+ diffusion efficiency, Ca2+ binding thermodynamics and molecular bases of Ca2+-dependent protein-protein interaction. Specifically, we studied 1) the electrokinetic transport of Ca2+ in confined sub-µm geometry with complicated surfacial properties. We characterized the effective diffusion constant of Ca2+ in a cell-like environment, which helps to understand …


Xylan Metabolism By Caulobacter Crescentus, Viet Bui 2019 Eastern Illinois University

Xylan Metabolism By Caulobacter Crescentus, Viet Bui

Masters Theses

Bacteria present unique opportunities to explore the molecular mechanisms of nutrient acquisition processes at single cell level under various experimental conditions. Caulobacter crescentus is a gram-negative oligotrophic environmental bacterium with adaptive physiological responses, such as slow growth or complete arrest of cell cycle, presence of sessile and motile progenies with the sessile cells growing stalk to enhance nutrient uptake for growth in low-nutrient conditions. Details of plant polysaccharide-derived carbon compound, such as cellobiose, maltose, and xylose utilization by C. crescentus can be found but molecular details or mechanisms of polysaccharide utilization, such as xylan, has not been reported. Database analyses …


Structural Characterization Of Black Widow Spider Dragline Silk Proteins Crp1 And Crp4, Mikayla Shanafelt 2019 University of the Pacific

Structural Characterization Of Black Widow Spider Dragline Silk Proteins Crp1 And Crp4, Mikayla Shanafelt

University of the Pacific Theses and Dissertations

Spider dragline silk is a biomaterial with outstanding material properties, possessing high-tensile strength and toughness. In nature, dragline silk serves a central role during spider locomotion and web construction. Today, scientists are racing to elucidate the molecular machinery governing silk extrusion, attempting to translate this knowledge into a mimicry process in the laboratory to create synthetic fibers for a wide range of different applications. During extrusion, it has been established that biochemical and mechanical forces govern spidroin folding, aggregation, and assembly. In black widow spiders, at least 7 different proteins have been identified as constituents of dragline silk fibers. These …


Evaluating Methods Of Obtaining Male Pheromone From Hymenochirus Sp. Using Analytical Chemistry, Vincent Wing-Kun Leung 2019 University of the Pacific

Evaluating Methods Of Obtaining Male Pheromone From Hymenochirus Sp. Using Analytical Chemistry, Vincent Wing-Kun Leung

University of the Pacific Theses and Dissertations

Male Hymenochirus sp. frogs are known to release pheromone that attracts females of the same species. Four methods for collecting secretions containing pheromone in Hymenochirus sp. were tested: norepinephrine injection, gonadotropin-releasing hormone injection, homogenization of gland tissue, and electrostimulation of the skin over the breeding gland area. The samples collected were analyzed using high-performance liquid chromatography (HPLC) and mass spectrometry. The HPLC chromatograph for the male norepinephrine sample contained a peak at 6.4 min that was not in the female norepinephrine sample HPLC chromatograph. The male norepinephrine sample mass spectrum had a peak of m/z 292.0 not in the female …


Characterization Of The Effects Of Sex And Estrogen Receptor Signaling On Antigen-Specific T Cells For Immunotherapy, Flor Cecilia Navarro Negredo 2019 Loyola University Chicago

Characterization Of The Effects Of Sex And Estrogen Receptor Signaling On Antigen-Specific T Cells For Immunotherapy, Flor Cecilia Navarro Negredo

Dissertations

Adoptive cell transfer (ACT) immunotherapy using antigen (Ag)-specific T cells is partially effective treating several malignancies but numerous challenges remain in order to improve its therapeutic potential. The roles of host factors, such as sex hormone receptor signaling, that can affect the T cell anti-tumor function remain understudied. The work performed in this dissertation characterized the role of estrogen signaling on T cell function in vitro, and during ACT immunotherapy against hepatocellular carcinoma (HCC) in vivo. Estrogen signaling through ERa enhanced the expression and secretion of Type I effector cytokines including IFNg, TNFa, and Granzyme B in male and female …


Yczr, A New Case Of Plp-Dependent Mocr/Gabr Type Transcription Regulator In Klebsiella Pneumonia, Yuanzhang Zheng 2019 Loyola University Chicago

Yczr, A New Case Of Plp-Dependent Mocr/Gabr Type Transcription Regulator In Klebsiella Pneumonia, Yuanzhang Zheng

Dissertations

Increasing number of genes encoding PLP-dependent transcription regulators, MocR/GabR type regulators, have been identified in various bacterial genomes. However, only a handful of them, including MocR, PdxR and GabR have been studied experimentally. They control different aspects of the bacterial metabolism. Only GabR has reported crystallographic structures. MocR/GabR regulators possess a chimeric structure consisted of a WHTH DNA binding domain and an Aminotransferase-like regulation domain, which can bind PLP as an effector in transcription regulation. Such a chimeric construct presents an interesting case in molecular evolution. The regulation domains of All MocR/GabR type regulators loss their catalytic capacity during evolution …


Co-Expression Of Feedback Resistant Enzymes In Phenylalanine Biosynthesis Pathway To Increase Phenylalanine Production, Charintip Yenyuvadee 2019 Faculty of Science

Co-Expression Of Feedback Resistant Enzymes In Phenylalanine Biosynthesis Pathway To Increase Phenylalanine Production, Charintip Yenyuvadee

Chulalongkorn University Theses and Dissertations (Chula ETD)

L-Phenylalanine (L-Phe) is an important commercial amino acid. It is widely used in food and pharmaceutical industries. Currently, the requirement of L-Phe is increased according to the great demand for the low-calorie sweetener, aspartame. In Escherichia coli, the synthesis of L-Phe is controlled by the multi-hierarchical regulations. AroG isoform of 3-deoxy- D-arabino-heptulosonate-7-phosphate synthase (DAHP synthase) and chorismate mutase/prephenate dehydratase (PheA), two important enzymes, are feedback inhibited by LPhe. Co-expression of feedback-resistant pheA (pheA[superscript L359D]) with other pivotal genes in L-Phe biosynthesis pathway: aroB, aroL, phedh, tktA, aroG, pheA, yddG, and glpF in pRSFDuet-1 (pPTFBLYA[superscript L359D]) elevated L-Phe production of E. …


Functional Characterization Of Cytosolic Ddx41 Sensor In Mediating Antiviral Immune Response In Black Tiger Shrimp Penaeus Monodon, Suthinee Soponpong 2019 Faculty of Science

Functional Characterization Of Cytosolic Ddx41 Sensor In Mediating Antiviral Immune Response In Black Tiger Shrimp Penaeus Monodon, Suthinee Soponpong

Chulalongkorn University Theses and Dissertations (Chula ETD)

DEAD (Asp-Glu-Ala-Asp) box polypeptide 41 (DDX41), a receptor belonging to the DExD family, was recently identified as an intracellular DNA sensor in vertebrates. Here, we investigated the presence of cytosolic DNA sensing, DDX41 in shrimp Penaeus monodon. By searching for gene involved in DNA sensing cascade within the shrimp P. monodon EST database, 3 cDNA fragments exhibited similarity to DDX41 in various species were identified. Sequences assembly resulted in a complete ORF of Penaeus monodon DDX41 (PmDDX41) which has 1868-bp encoding a putative protein of 620 amino acid residues. The multiple sequence alignment of deduced amino acid sequence of PmDDX41 …


Fructooligosaccharide Synthesis By Immobilized Inulosucrase From Lactobacillus Reuteri 121 And Improvement Of Product Pattern Using Site-Directed Mutagenesis, Thanapon Charoenwongpaiboon 2019 Faculty of Science

Fructooligosaccharide Synthesis By Immobilized Inulosucrase From Lactobacillus Reuteri 121 And Improvement Of Product Pattern Using Site-Directed Mutagenesis, Thanapon Charoenwongpaiboon

Chulalongkorn University Theses and Dissertations (Chula ETD)

Inulin-type fructooligosaccharides (IFOS) are well-known prebiotics which can be produced from sucrose using bacterial inulosucrase (E.C. 2.4.1.9). However, the use of inulosucrase for IFOS synthesis has some limitations because it also synthesizes some polysaccharides and exhibits lower stability than the fungal enzymes. To overcome these limitations, improvement of inulosucrase was made by using enzyme immobilization and enzyme engineering. First, inulosucrase from Lactobacillus reuteri 121 was immobilized on a novel, high capacity core-shell chitosan beads using glutaraldehyde as a cross-linker. The results showed that both immobilized and free inulosucrase had the same optimum pH (5.5), while the optimum temperature was shifted …


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