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Reactions Of Platinum(Ii) Compounds With Selenium Containing Amino Acids, Stephanie Robey May 2013

Reactions Of Platinum(Ii) Compounds With Selenium Containing Amino Acids, Stephanie Robey

Masters Theses & Specialist Projects

Platinum(II) anticancer medications essentially react with DNA forming kinks in
the double helix of DNA and causing apoptosis. It has also been noted that these
anticancer medications react with methionine and cysteine in the body. With the new discoveries of selenium containing amino acids including selenomethionine and selenocysteine, new research is ongoing to see what types of products can be formed from these amino acids. Our research reacts [Pt(Met-S,N)Cl2] 2+ with selenomethionine to determine what types of products are produced. Monochelates including [Pt(SeMet-Se,N)Cl2] 2+ have formed two isomers, …


Effect Of Leaving Ligands Of Platinum(Ii) Diamine Complexes On Dna And Protein Residues, Ramya Kolli May 2013

Effect Of Leaving Ligands Of Platinum(Ii) Diamine Complexes On Dna And Protein Residues, Ramya Kolli

Masters Theses & Specialist Projects

Platinum compounds are widely used drugs in cancer treatments. Although DNA is the biological target, reaction of platinum compounds with proteins is also potentially significant. Our objective is to study the effects of leaving ligands on the relative reactivity between 5'-GMP (guanosine 5' phosphate), a key DNA target, and N-Acetyl - L-Methionine (N-AcMet), a key protein target. We have used NMR spectroscopy to monitor reactions with N-AcMet and 5'-GMP added to a platinum complex to see which products are formed preferentially. Previous research showed that both a non-bulky complex such as [Pt(en)(D2O)2]2+ [en=ethylenediamine], and a …


Effects Of Cisplatin Analog Size On The Reaction With Dna Bases, Swathi Nandala May 2013

Effects Of Cisplatin Analog Size On The Reaction With Dna Bases, Swathi Nandala

Masters Theses & Specialist Projects

Cancer is the second leading cause of death in the United States. Cisplatin is one of the well-known anti-cancer agents used to treat testicular and ovarian cancers. It mainly binds to the DNA bases, which leads to cell death. The cytotoxic activity of the cisplatin analogs is due to the interaction of platinum with nucleotides like adenine at N7 or N1 position and guanine at N7 position. Guanine is the primary target for cisplatin analogs whereas adenine is the secondary target. Cisplatin analogs, [Pt(Me5dien)(D2O)]2+[Me5dien = N,N,N’,N’,N’’-pentamethyl diethylene triamine] and …


Sensing Of Carboxylate Drugs In Urine By A Supramolecular Sensor Array, Yuanli Liu, Tsuyoshi Minami, Ryuhei Nishiyabu, Zhuo Wang, Pavel Anzenbacher Jr. May 2013

Sensing Of Carboxylate Drugs In Urine By A Supramolecular Sensor Array, Yuanli Liu, Tsuyoshi Minami, Ryuhei Nishiyabu, Zhuo Wang, Pavel Anzenbacher Jr.

Chemistry Faculty Publications

A supramolecular sensor array consisting of eight chemosensors embedded in a hydrogel matrix was used to sense carboxylate drugs. The discriminatory power of the array has been evaluated using principal component analysis and linear discriminant analysis. The eight-member sensor array has been shown to accurately identify 14 carboxylates in water with 100% classification accuracy. To demonstrate the potential for practical utility in the physiological environment, analysis of carboxylate drugs in human urine was also performed achieving 100% correct classification. In addition, the array performance in semiquantitative identification of nonsteroidal anti-inflammatory drugs has been investigated, and the results show that the …


I. Norbornene As Organocatalyst: Unusual: Amination Ii. Stereoselective Synthesis Of 3, 4 Di-Substituted Β-Lactams; Classical Vs Microwave Method, Ravi Reddaboyna May 2013

I. Norbornene As Organocatalyst: Unusual: Amination Ii. Stereoselective Synthesis Of 3, 4 Di-Substituted Β-Lactams; Classical Vs Microwave Method, Ravi Reddaboyna

Theses and Dissertations - UTB/UTPA

I. Amine functionality is important in the preparation of biologically active and industrially useful molecules. Many approaches to form C―N bonds provide access to fine chemical building blocks, pharmaceuticals, agrochemicals, and surfactants. Microwave irradiation is a highly recommended ecofriendly approach for the synthesis of medicinally important compounds. Organic catalysis is important segment in the field of organic chemistry, for the synthesis of many complex molecules by providing a number of advantages.

II. Cancer refers to a large group of diseases characterized by uncontrolled cell multiplication and the ability of these cells to enter other tissues and spread to other parts …


Section Abstracts: Chemistry May 2013

Section Abstracts: Chemistry

Virginia Journal of Science

Abstracts of the Chemistry Section for the 91st Annual Virginia Journal of Science Meeting, May 2013


Spectroscopic Investigation Of The Interaction Of Fadh In Dna Photolyase With Uv-Damaged Dna, Kyle Luke Williams May 2013

Spectroscopic Investigation Of The Interaction Of Fadh In Dna Photolyase With Uv-Damaged Dna, Kyle Luke Williams

Theses, Dissertations and Culminating Projects

Skin cancer is the most prevalent malignancy found in humans, with the diagnosis rate continuing to steadily increase. The primary cause of this disease is overexposure to harmful ultraviolet (UV) radiation from sunlight, which can induce damage to the nitrogenous bases in DNA via dimerization. The most prevalent UV-induced photoproducts in DNA are cyclobutane pyrimidine dimers (CPDs), most commonly between adjacent thymidines.

Organisms have implemented methods by which to repair these CPDs, the primary of which are nucleotide excision repair (NER) and photoreactivation by photolyases. Photolyases are blue-light activated flavoproteins that are more efficient at recognizing and repairing CPDs than …


Electrospinning Nanofibers For Controlled Drug Release, Indrani Banik May 2013

Electrospinning Nanofibers For Controlled Drug Release, Indrani Banik

Theses and Dissertations - UTB/UTPA

Electrospinning is the most widely studied technique for the synthesis of nanofibers. Electrospinning is considered as one of the technologies that can produce nanosized drugs incorporated in polymeric nanofibers. In vitro and in vivo studies have demonstrated that the release rates of drugs from these nanofiber formulations are enhanced compared to those from original drug substance. This technology has the potential for enhancing the oral delivery of poorly soluble drugs [1]. The electrospun mats were made using Polycaprolactone/PCL, Poly(DL-lactide)/PDL 05 and Poly(DL-lactide-co-glycolide)/PLGA. The drugs incorporated in the electrospun fibers were 5-Fluorouracil and Rapamycin. The evidence of the drugs being embedded …


Study Of Immobilizing Cadmium Selenide Quantum Dots In Selected Polymers For Application In Peroxyoxalate Chemiluminescence Flow Injection Analysis, Christopher S. Moore May 2013

Study Of Immobilizing Cadmium Selenide Quantum Dots In Selected Polymers For Application In Peroxyoxalate Chemiluminescence Flow Injection Analysis, Christopher S. Moore

Electronic Theses and Dissertations

Two batches of CdSe QDs with different sizes were synthesized for immobilizing in polyisoprene (PI), polymethylmethacrylate (PMMA), and low-density polyethylene (LDPE). The combinations of QDs and polymer substrates were evaluated for their analytical fit-for-use in applicable immunoassays. Hydrogen peroxide standards were injected into the flow injection analyzer (FIA) constructed to simulate enzyme-generated hydrogen peroxide reacting with bis-(2,4,6-trichlorophenyl) oxalate.

Linear correlations between hydrogen peroxide and chemilumenscent intensities yielded regression values greater than 0.9750 for hydrogen peroxide concentrations between 1.0 x 10-4 M and 1.0 x 10-1 M. The developed technique’s LOD was approximately 10 ppm. Variability of the prepared …


Aerobic Degradation Of Α-, Β-, Γ-Hexachlorocyclohexane By Narragansett Bay Bacterioplankton, Ian M. Rambo May 2013

Aerobic Degradation Of Α-, Β-, Γ-Hexachlorocyclohexane By Narragansett Bay Bacterioplankton, Ian M. Rambo

Senior Honors Projects

Hexachlorocyclohexanes (HCHs) are a family of chlorinated organic compounds that were previously used as agricultural insecticides. HCHs are recognized as persistent organic pollutants due to their toxicity, recalcitrant properties, and tendency to bioaccumulate in food webs. Although HCH was first synthesized in 1825, its use was not widespread until the discovery of the insecticidal activity of the γ-HCH isomer in 1942. γ-HCH and its toxic waste isomers α-HCH and β-HCH were banned from production and use by the United Nations in 2009, yet these chemicals still present environmental problems due to their persistence in soils and surface waters. HCHs continue …


Modeling Amyloid-Ss Self-Assembly : Stability Of On-Pathway Aggregate Formation, Andrew Kevin Mauro May 2013

Modeling Amyloid-Ss Self-Assembly : Stability Of On-Pathway Aggregate Formation, Andrew Kevin Mauro

Theses, Dissertations and Culminating Projects

Protein misfolding and concomitant aggregation towards amyloid formation is the underlying biochemical commonality among a wide range of human pathologies. Amyloid formation involves the conversion of proteins from their native monomeric states (intrinsically disordered or globular) to well-organized, fibrillar aggregates in a nucleation-dependent manner. Understanding the mechanism of aggregation is important not only to gain better insight into amyloid pathology but also to simulate and predict molecular pathways. One of the main impediments in doing so is the highly stochastic nature of interactions that complicates the development of meaningful insights. In this study, we have utilized a well-characterized intermediate along …


An Investigation Of The Electronic Coupling In Some Dimeric Ruthenium (Ii) Polypyridine Complexes, Roland Ngebichie Njabon May 2013

An Investigation Of The Electronic Coupling In Some Dimeric Ruthenium (Ii) Polypyridine Complexes, Roland Ngebichie Njabon

Graduate Theses and Dissertations

A detailed understanding of respiration at the molecular level requires an understanding of the many electron transfer steps involved in the process. These electron transfer processes are extremely fast and are impossible to measure by simple rapid mixing techniques. In order to get around this problem, scientists have used laser flash photolysis. This technique relies on the fact that under proper conditions, a reactant can be generated by a very short laser pulse. Once generated, the course of the reaction can be monitored by various techniques capable of very rapid time response. Many applications of this methodology rely on the …


Improving Student Learning Of Organic Chemistry By The Use Of Case Comparisons., Divine-Favour Ekene Anene May 2013

Improving Student Learning Of Organic Chemistry By The Use Of Case Comparisons., Divine-Favour Ekene Anene

College of Arts & Sciences Senior Theses

No abstract provided.


Pd-­Catalyzed N-­Arylation Of Amides: Catalyst Development And Scope, Tara Brenner May 2013

Pd-­Catalyzed N-­Arylation Of Amides: Catalyst Development And Scope, Tara Brenner

Renée Crown University Honors Thesis Projects - All

Recent development toward more efficient palladium catalyzed amidation reactions has been driven by mechanistic studies and the development of more efficient ancillary phosphine ligands. This review discusses these developments with regard to substrate scope and the nature of the corresponding catalyst systems. Emphasis will be placed on applications of palladium catalyzed amidation reactions and the synthetic utility of these methods.


The Conjugation Of Protein And Peptide Therapeutics To Vitamin B12 For The Oral Treatment Of Diabetes, Jamie L. Bernstein May 2013

The Conjugation Of Protein And Peptide Therapeutics To Vitamin B12 For The Oral Treatment Of Diabetes, Jamie L. Bernstein

Renée Crown University Honors Thesis Projects - All

Currently patients with diabetes receive most of their treatments, including insulin, subcutaneously. Developing a method to orally deliver proteins, peptides, and potentially other therapeutics has the ability to increase patient compliance by making treatments easier to administer. Utilizing the Vitamin B12 uptake pathway is one proposed method of oral delivery of protein therapeutics. We investigated a way to synthesize a carboxylic acid derivative of Vitamin B12 (B12) that could increase the ease of its conjugation to proteins and peptides. The 5’-position of the ribose tail of B12 was oxidized using excess 2-iodoxybenzoic acid (IBX) and 2-hydroxypyridine (HYP). The synthesis of …


The Use Of P53-Derived Stapled Peptides As Affinity Isolation Reagents, Kathryn Margaret Headley May 2013

The Use Of P53-Derived Stapled Peptides As Affinity Isolation Reagents, Kathryn Margaret Headley

Renée Crown University Honors Thesis Projects - All

The transcription factor p53 can induce apoptosis and cell cycle arrest in response to cellular distress. Cancer cells often display increased cell survival. In most cases, this is due to a p53-related defect, such as mutation, deletion, degradation, or sequestration. HDM2 and HDMX are homologous proteins that regulate the function of p53, and their over-expression can lead to an ineffective p53 response. Various inhibitors, including hydrocarbon stabilized alpha-helices of p53 (SAH-p53s), have been developed to target HDM2 and HDMX and restore functionality to the p53 pathway. It has been recently found that SAH-p53 factors also elicit cell death responses in …


Characterization Of Dap2 (Defense-­‐Associated Aspartic Protease-­‐2) In Arabidopsis Thaliana And Determining Its Role In Plant Defense Responses, Kemardo Kitaro Henry May 2013

Characterization Of Dap2 (Defense-­‐Associated Aspartic Protease-­‐2) In Arabidopsis Thaliana And Determining Its Role In Plant Defense Responses, Kemardo Kitaro Henry

Renée Crown University Honors Thesis Projects - All

Plants defend themselves from invading pathogens by coordinating activity of several plant defense-­‐associated genes. Defense-­‐Associated Aspartic Protease-­‐1 (DAP1) gene of Arabidopsis encodes for an atypical aspartic protease with a putative proteolytic activity. The DAP1 is a negative regulator of plant immunity and the transgenic plants ectopically expressing this genes support pathogen growth and pathogenicity. The Arabidopsis genome has another putative protese that has ~75% homology to DAP1 present in close proximity and therefore was named DAP2. Here, I describe the role of the DAP2 gene in plant defense responses. Two independent knockout dap2 mutants are found to be more susceptible …


Vitamin B12-Based Bioconjugate Probes For In Vitro And In Vivo Imaging, Anna Kahkoska May 2013

Vitamin B12-Based Bioconjugate Probes For In Vitro And In Vivo Imaging, Anna Kahkoska

Renée Crown University Honors Thesis Projects - All

Cancer is the second leading cause of death in the United States. This year, an estimated 577,190 Americans will die as a result of this family of diseases. Finding cancer at its most treatable stage gives patients the greatest chance of recovery; novel imaging agents that target primary and metastasized tumors offer hope for improved prognoses in the future. Based on the hypothesis that vitamin B12 (B12) and its association with specific transport proteins could offer selective access to cancer cell lines, a series of B12-based imaging agents were synthesized, characterized, and assayed for both in vitro and in vivo …


Iron Citrate Toxicity Causes Aco1Δ-Induced Mtdna Loss In Saccharomyces Cerevisiae, Muhammad Ali Farooq May 2013

Iron Citrate Toxicity Causes Aco1Δ-Induced Mtdna Loss In Saccharomyces Cerevisiae, Muhammad Ali Farooq

Senior Honors Theses

Aconitase is an enzyme of the Krebs cycle that catalyzes the isomerization of citrate to isocitrate. In addition to its enzymatic activity, Aco1 has been reported to bind to mitochondrial DNA (mtDNA) and mediate its maintenance in the budding yeast S. cerevisiae. In the absence of Aco1, cells rapidly lose mtDNA and become “petite” mutants. The purpose of this study is to uncover the mechanism behind mtDNA loss due to an aco1 deletion mutation. We found that an aco1 mutation activates the mitochondria-to-nucleus retrograde (RTG) signaling pathway, resulting in increased expression of citrate synthases (CIT) through the activation of two …


Synthesis Of Dibenzofurans Via A Palladium Catalyzed Oxidative Ring Closure Reaction, Sadia Akram May 2013

Synthesis Of Dibenzofurans Via A Palladium Catalyzed Oxidative Ring Closure Reaction, Sadia Akram

Senior Honors Theses

The cannabinoid partial agonist BAY 59-3704 has been identified as an attractive target to explore structure-activity relationships at cannabinoid receptors for the development of a therapeutic agent for psychostimulant addiction. This thesis will describe the studies associated with the optimization of a palladium-catalyzed oxidative ring closure reaction for the synthesisof dibenzofuran analogues from substituted diaryl ethers. These dibenzofurans are viewed as rigid analogues of BAY 59-3704 and will provide useful information about molecular interactions at cannabinoid receptors. The scope and limitations of the palladium-catalyzed oxidative ring closure reaction as it relates to the synthesis of the target dibenzofuran analogues will …


Regulation Of Secondary Metabolism In Lysobacter Enzymogenes: Studies Of Intercellular And Intracellular Signaling, Stephen J. Wright May 2013

Regulation Of Secondary Metabolism In Lysobacter Enzymogenes: Studies Of Intercellular And Intracellular Signaling, Stephen J. Wright

Department of Chemistry: Dissertations, Theses, and Student Research

The organisms of the genus Lysobacter have been recognized as prolific producers of bioactive secondary metabolites, making them potentially valuable as biocontrol agents and as sources of compounds for drug leads. This study was aimed at understanding the regulatory mechanisms that underlie the production of secondary metabolites in our study organism, Lysobacter enzymogenes. Since secondary metabolism is energetically costly, we sought not only to elucidate the biosynthetic chemistry by which the bioactive molecules were constructed, but also the regulation of the biosynthetic machinery. The molecular mechanisms by which L. enzymogenes responds to environmental conditions and transduces signals leading to …


Squaraine Dyes For Two-Photon Fluorescence Bioimaging Applications, Maria Colon Gomez May 2013

Squaraine Dyes For Two-Photon Fluorescence Bioimaging Applications, Maria Colon Gomez

HIM 1990-2015

No abstract provided.


Examining The Substrate Specificity Of Factor Xiiia Towards Peptide Substrate Modelsac Fibrin Domains., Jacob Bell May 2013

Examining The Substrate Specificity Of Factor Xiiia Towards Peptide Substrate Modelsac Fibrin Domains., Jacob Bell

College of Arts & Sciences Senior Theses

In the blood coagulation cascade, Factor XIII (FXIII) is a zymogen that is activated by thrombin (IIa) and Ca2+. Activated FXIII (FXIIIa) functions as a transglutaminase in the final steps of the clotting cascade by forming covalent crosslinks between fibrin monomers at reactive glutamine residues. This forms a stable clot structure, secure from proteolytic degradation. To monitor FXIIIa substrate sequence specificity, the glutamine-containing peptide models S. aureus Fnb A (100-114), α2AP(Q4P) (1-15) and K9 (1-10) were introduced to the enzyme in the presence of 15NH4Cl. Using MALDI-TOF MS and 15N HSQC NMR experiments, it was seen that α2AP(Q4P) (1-15) and …


The Investigation Of Protonation Of [Mo2(Nto)2(S2p(Oet)2)2(So)(Sbn)(O2cme)]., Adria Schwarber May 2013

The Investigation Of Protonation Of [Mo2(Nto)2(S2p(Oet)2)2(So)(Sbn)(O2cme)]., Adria Schwarber

College of Arts & Sciences Senior Theses

No abstract provided.


Enhanced Structural Support Of Metal Sites As Nodes In Metal-Organic Frameworks Compared To Metal Complexes, Sanjit Das May 2013

Enhanced Structural Support Of Metal Sites As Nodes In Metal-Organic Frameworks Compared To Metal Complexes, Sanjit Das

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Crystalline porous materials have gained long-standing interest for their application in gas storage, separation and catalysis. These materials have been useful for domestic, scientific and industrial purposes for many decades. Zeolites are a well known example of such materials.

Metal-organic frameworks are a new class of crystalline porous materials. They have many advantages over the more widely known zeolites. Though metal-organic frameworks are relatively new, their basic structure, known as the secondary building unit, very closely resembles the structure of metal complexes. Such metal complexes have been characterized in chemistry for more than a century.

Chemical catalysis is a process …


Structural And Functional Characterization Of The Ldp3 (Vhz) Protein Tyrosine Phosphatase, Vyacheslav I. Kuznetsov May 2013

Structural And Functional Characterization Of The Ldp3 (Vhz) Protein Tyrosine Phosphatase, Vyacheslav I. Kuznetsov

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Protein phosphorylation is as an important regulatory mechanism that controls a large number of physiologically important cellular processes. Proteins are phosphorylated on aliphatic (serine and threonine) as well aromatic (histidine and tyrosine) residues predominantly located on sterically accessible loops. Phosphorylation affects three- dimensional structures of proteins resulting in conformational changes which activate or deactivate enzymatic functions. Because of the ability of protein phosphorylation to modulate a multitude of diverse cellular processes, it became an appealing and promising target for drug therapy.

Attachment of phosphate is accomplished by kinases, whereas the removal of the phosphoryl group is performed by protein phosphatases. …


Oxidative Aliphatic Carbon-Carbon Bond Cleavage Reactions, Caleb J. Allpress May 2013

Oxidative Aliphatic Carbon-Carbon Bond Cleavage Reactions, Caleb J. Allpress

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The work presented in this dissertation has focused on the activation and cleavage of chemical bonds between two carbon atoms. The selective oxidative activation of carbon-carbon bonds is important due to potential applications in the utilization of biomass for fuel production, applications in wastewater treatment and bioremediation, and in developing new reactions for organic synthesis of fine chemicals including pharmaceuticals. Ideally these reactions would be carried out with high atom economy at low temperatures and pressures, and using earth-abundant elements as reagents and catalysts. With these points in mind, nature provides an ideal model framework, carrying out its chemistry at …


What Can Biochemistry Students Learn About Protein Translation? Using Variation Theory To Explore The Space Of Learning Created By Some Common External Representations, Thomas J. Bussey May 2013

What Can Biochemistry Students Learn About Protein Translation? Using Variation Theory To Explore The Space Of Learning Created By Some Common External Representations, Thomas J. Bussey

UNLV Theses, Dissertations, Professional Papers, and Capstones

Biochemistry education relies heavily on students' ability to visualize abstract cellular and molecular processes, mechanisms, and components. As such, biochemistry educators often turn to external representations to provide tangible, working models from which students' internal representations (mental models) can be constructed, evaluated, and revised. However, prior research has shown that, while potentially beneficial, external representations can also lead to alternative student conceptions.

Considering the breadth of biochemical phenomena, protein translation has been identified as an essential biochemical process and can subsequently be considered a fundamental concept for biochemistry students to learn. External representations of translation range from static diagrams to …


Chiral Analyses Of Ephedrines, Lyanne Valdez May 2013

Chiral Analyses Of Ephedrines, Lyanne Valdez

Honors College Theses

Chiral molecules rotate plane-polarized light and have two or more forms known as enantiomers. We plan to separate the two enantiomeric ephedrines using β-cyclodextrin column in gas chromatography-mass spectrometry (GC-MS).To achieve this, a series of methods were developed through the modification of temperature and mobile phase parameters.


Dynamic Bioactive Stimuli-Responsive Polymeric Surfaces, Heather Marie Pearson May 2013

Dynamic Bioactive Stimuli-Responsive Polymeric Surfaces, Heather Marie Pearson

Dissertations

This dissertation focuses on the design, synthesis, and development of antimicrobial and anticoagulant surfaces of polyethylene (PE), polypropylene (PP), and poly(tetrafluoroethylene) (PTFE) polymers. Aliphatic polymeric surfaces of PE and PP polymers functionalized using click chemistry reactions by the attachment of –COOH groups via microwave plasma reactions followed by functionalization with alkyne moieties. Azide containing ampicillin (AMP) was synthesized and subsequently clicked into the alkyne prepared PE and PP surfaces. Compared to non-functionalized PP and PE surfaces, the AMP clicked surfaces exhibited substantially enhanced antimicrobial activity against Staphylococcus aureus bacteria. To expand the biocompatibility of polymeric surface …