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Chemistry & Biochemistry Guest Lecture Series, Desmond Murray

Andrews Agenda: Campus News

No abstract provided.

Dual Geometry Schemes In Tetrel Bonds: Complexes Between Tf4(T = Si, Ge, Sn) And Pyridine Derivatives, Wiktor Zierkiewicz, Mariusz Michalczyk, Rafał Wysokiński, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

When an N-base approaches the tetrel atom of TF4(T = Si, Ge, Sn) the latter moleculedeforms from a tetrahedral structure in the monomer to a trigonal bipyramid. The base can situateitself at either an axial or equatorial position, leading to two different equilibrium geometries.The interaction energies are considerably larger for the equatorial structures, up around 50 kcal/mol,which also have a shorter R(T··N) separation. On the other hand, the energy needed to deform thetetrahedral monomer into the equatorial structure is much higher than the equivalent deformationenergy in the axial dimer. When these two opposite trends are combined, it is the axial …

Development Of Ultrafast Broadband Electronic Sum Frequency Generation For Charge Dynamics At Surfaces And Interfaces, Gang-Hua Deng, Yuqin Qian, Yi Rao

Chemistry and Biochemistry Faculty Publications

Understandings of population and relaxation of charges at surfaces and interfaces are essential to improve charge collection efficiency for energy conversion, catalysis, and photosynthesis. Existing time-resolved surface and interface tools are limited to either under ultrahigh vacuum or in a narrow wavelength region with the loss of spectral information. There lacks an efficient time-resolved surface/interface-specific electronic spectroscopy under ambient conditions for the ultra fast surface/interface dynamics. Here we developed a novel technique for surface/interface-specific broadband electronic sum frequency generation (ESFG). The broadband ESFG was based on a stable two-stage BiB₃O₆ crystal-based optical parametric amplifier, which generates a …

Fabrication Of Miniaturized Paper-Based Microfluidic Devices (Micropads), E. Brandon Strong, Spencer A. Schultz, Andres Martinez, Nathaniel W. Martinez

Chemistry and Biochemistry

Microfluidic paper-based analytical devices (microPADs) are emerging as cost-effective and portable platforms for point-of-care assays. A fundamental limitation of microPAD fabrication is the imprecise nature of most methods for patterning paper. The present work demonstrates that paper patterned via wax printing can be miniaturized by treating it with periodate to produce higher-resolution, high-fidelity microPADs. The optimal miniaturization parameters were determined by immersing microPADs in various concentrations of aqueous sodium periodate (NaIO₄) for varying lengths of time. This treatment miniaturized microPADs by up to 80% in surface area, depending on the concentration of periodate and length of the reaction …

Differential Binding Of Tetrel-Bonding Bipodal Receptors To Monatomic And Polyatomic Anions, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

Previous work has demonstrated that a bidentate receptor containing a pair of Sn atoms can engage in very strong interactions with halide ions via tetrel bonds. The question that is addressed here concerns the possibility that a receptor of this type might be designed that would preferentially bind a polyatomic over a monatomic anion since the former might better span the distance between the two Sn atoms. The binding of Cl⁻ was thus compared to that of HCOO⁻, HSO₄⁻, and H₂PO₄⁻ with a wide variety of bidentate receptors. A pair …

Identifying C-Mannosylatedproteins In Raw264.7 Cells Via In Vitro Hsc70 Co-Immunoprecipitation Strategies, Nicholas Ryan Kegley

Theses, Dissertations and Capstones

C-mannosylation is a specific type of glycosylation in which α-mannose is covalently bound to the C2 atom of a tryptophan via a carbon-carbon bond. Presently, it is known to occur on proteins that contain the W-x-x-W-x-x-W/C motif found within the Thrombospondin Type-1 Repeat (TSR), with ‘x’ denoting any amino acid. C-mannosylation has been implicated in a number of cellular functions, including protein secretion and type I cytokine receptor function. Previous research has shown that exogenous C-mannosylated peptides derived from TSR-containing proteins upregulate the production of the pro-inflammatory cytokine Tumor Necrosis Factor alpha (TNF-α) in RAW264.7 macrophage cells. This upregulation is …

Characterizing The Effects Of Environmental Stressors On The Photosynthetic Capacity Of Chlorella Vulgaris, Amanda Louise Smythers

Theses, Dissertations and Capstones

Chlorella vulgaris is a unicellular green algae grown throughout the world. Due to its multiple trophic modes as well as its ability to maintain high rates of growth under adverse conditions, it has been of global interest for use in ecological contamination studies, biofuel feedstock optimization, and studies of photosynthetic electron transfer. Using a wide-range of methods for physiological and photosynthetic characterization, the studies within seek to further extend the usefulness of C. vulgaris in a variety of environmentally important studies. Once the protocols were optimized specifically for this alga, they could be applied in both ecologically relevant and biodiesel …

Isolation And Identification Of Hsc70 Conjugates In Raw264.7 Murine Macrophage-Like Cells, Michael Arland Parsons

Theses, Dissertations and Capstones

IL12R- β2 is a Type I cytokine receptor and contains the WXXW (WSNWS) sequence that often predicates the post-translational addition of mannose to a tryptophan residue via a carbon-carbon bond. This study will stimulate expression of IL12R- β2 in RAW 264.7 Macrophage-Like Cells by shutting down the extracellular signal kinase (ERK) pathway and introducing inflammatory agents lipopolysaccharide and CpG DNA in order to collect a concentrated sample of IL12R- β2. These samples will be analyzed for the presence of C-mannosyltryptophan residue

Development Of A Hek293 Cell Line To Show Inhibition Of Tau Aggregation, Justin Ray Shady

Electronic Theses and Dissertations

Intracellular deposition of aggregated tau is the hallmark of several different tauopathies, the most widespread of these being Alzheimer's disease. Tau is a highly soluble, intrinsically disordered, microtubule associated protein. Tau's native function is to stabilize microtubule formation in the axons of neurons. Post translational modification such as hyperphosphorylation as well as several familial mutations allow tau to nucleate and form fibrils. These fibrils can recruit healthy monomers onto their ends in a fashion described as template-assisted growth. Tau has 6 isoforms that vary by the inclusion or exclusion of two N-terminal repeats and the inclusion or exclusion of the …

Synthesis Of Trisubstituted Indolizines From 2-Propargyloxypyridines, Colin T. Hartgerink, Jaimie E. Van De Burg, Carolyn E. Anderson

Summer Research

• Indolizines are a versatile heterocyclic core that occurs frequently in pharmaceutical leads for a variety of indications, including: anti-bacterial1 and anti-tumor agents,2 and targets for the treatment of Alzheimer’s disease,3 asthma,4 erectile dysfunction,5 and inflammation related to respiratory or cardiovascular disease.
• While evaluating the scope of a Au(I)-catalyzed rearrangement of 2- propargyloxypyridine 1, 7 substituted indolizine 4 was discovered as an unexpected by-product (Scheme 1). The structure of indolizine 4 was confirmed by NMR and Xray analysis. Investigations revealed that acetophenone, originally present as an impurity in the reaction, is a key reagent. The use of acetophenone as the solvent, …

Split Probe Detection Of The Influenza A Virus For Improved Diagnostics In A Point Of Care System, Tamar Yishay

Honors Undergraduate Theses

A group of Influenza viruses, RNA containing viruses of the Orthomyxoviridae family, consists of Influenza virus types A-D and has been known to cause the Flu, a respiratory illness associated with numerous detrimental symptoms that can lead to death. Influenza A virus (IAV) is constantly changing and is capable of causing pandemics. Currently used diagnostic methods include virus culturing, immunoassays including rapid influenza detection tests (RIDTs), and molecular assays including those based on RT-PCR. Most of the methods can be only performed in the certified diagnostic laboratories equipped with sophisticated instrumentation and/or special biosafety facilities. The results using these methods …

Urinalysis Screening Of Drugs In Adulterated Samples Via Direct Analysis In Real Time -- High Resolution/ Mass Spectrometry (Dart-Hr/Ms), Bianca E. Olivieri

Honors Undergraduate Theses

Current screening methods for drug analysis with urine samples includes examination of the sample with an immunoassay. These methods are used to determine the concentration of drug metabolites contained within the sample prior to further confirmatory testing. Drug testing plays a crucial role in maintaining safe workplace environments and safety of individuals. However, a positive result can lead to heavy consequences for the employee including suspension or removal from the workplace. Therefore, a majority of individuals add commonly known products into the sample to evade detection by developing a false negative result. Although specimen integrity examinations are performed to identify …

Seven Coordinate Molybdenum And Tungsten Complexes Containing Tpm And Tpm Derivatives And The Impact Of Ligand Substitution On Nmr Chemical Shifts, Cole Seager

Undergraduate Honors Thesis Collection

A series of known and new seven coordinate molybdenum and tungsten complexes of tris(pyrazolyl)methane (Tpm) and substituted Tpm, [TpmM(CO)3X]+, have been synthesized. Depending on the identity of X, (bromo, iodo, hydrido) and the substitution of the Tpm ligand, substantial chemical shift differences are observed for the hydrogen on the central carbon of the Tpm ligand. Factors impacting the chemical shift of the hydrogen on the central carbon of the Tpm ligand, such as the electron donating ability of the Tpm ligand and the electronegativity of the additional ligand on the metal, will be discussed.

Biometal-Induced Structural Consequences Of Α-Synuclein – The Parkinson’S Disease Protein, Dinendra L. Abeyawardhane

Theses and Dissertations

The pre-synaptic protein α-Synuclein (αS) is often linked to the pathology of Parkinson’s disease (PD), an age-related neurodegenerative disorder. Lewy bodies, the cytopathological hallmarks of PD, are found to be rich in aggregates of misfolded αS protein. Metal dyshomeostasis has also been linked to PD due to the accumulation of iron in the substantia nigra pars compacta, and diminished copper levels reported in this same region. Metal dyshomeostasis in the brain coupled with oxidative stress can enhance the aggregation of αS. Recently, it was confirmed that mammalian αS is universally acetylated at the N-terminus, a common post-translational modification in …

Case Studies Of Potential Reference Materials In Cultural Heritage Science, Heidi Kastenholz

Undergraduate Honors Thesis Collection

The study of cultural heritage objects requires reference materials for comparison in order to determine the identity of chemical compounds in historically/culturally significant artifacts. The reference materials available today can be inaccurately labeled, can contain inauthentic compounds, or can simply be formed differently than what the labeled material should be. Utilizing the laboratory at the Indianapolis Museum of Art at Newfields, three case studies were conducted over three different potential reference materials in order to properly identify each of the three materials being focused on here. Based on the analysis, the labels for these materials often do not match the …

Assessment Of Quantity And Quality Of Microplastics In The Sediments, Waters, Oysters, And Selected Fish Species In Key Sites Along The Bombong Estuary And The Coastal Waters Of Ticalan In San Juan, Batangas, Emilyn Q. Espiritu, Sophia Angeli Sn Dayrit, Annabel Soledad O. Coronel, Natasha Sophia C. Paz, Pilar Isabel L. Ronquillo, Virgil Christian G. Castillo, Erwin P. Enriquez

Chemistry Faculty Publications

Microplastics (or MPs; < 5 mm in size) pollution is largely unstudied in the Philippines. From an environmental sustainability standpoint, it is important to understand the characteristics, abundance, and environmental fate of plastic debris of various sizes, and these include microplastics that are not more easily and readily detected. In this study, we assessed the extent of microplastics contamination in the sediments, waters, oysters, and selected fishes found in the rivers and coastal areas of Ticalan, Batangas, which were identified from water quality parameters as Class C and CS, respectively. The microplastics were extracted from these samples by chemical digestion of the matrix, series of filtration, and separation by flotation through a density gradient to finally isolate the microplastics which were not dissolved by chemical digestion. The isolated samples were imaged by optical microscopy and characterized based on their descriptive attributes. The results showed the presence of microplastics in all the samples tested, which were found mostly in the form of filaments, fragments, films, and pellets – with most showing weathered, degraded, or angular and irregular surfaces. Identification was done through spectral matching of the Fourier transform infrared spectra of isolated fragments with that of known plastics, although identification in some cases is made uncertain by possibility of degradation of the plastics in the environment. The majority of the isolates showed signature absorption bands of the C-H stretching vibrations of polyethylene-based plastics.

Inhibition Of Hsv-1 Binding By Egcg-Stearate, Valerie Paschalis

Theses, Dissertations and Culminating Projects

Herpes simplex virus type 1 (HSV-1) is the causative agent of oral herpes, and is able to establish lifelong latent infection along with painful, recurring symptoms. Epigallocatechin-3- gallate (EGCG) is the most abundant polyphenol derived from green tea (Camellia sinensis), whose anti-inflammatory, antioxidant, anti-cancer, and antiviral properties have been widely studied. Although EGCG is not chemically stable and has poor hydrophobicity, lipophilic derivatives of EGCG have shown increased stability as well as increased antiviral efficacy against HSV. Previous studies have demonstrated that EGCG stearate (EGCG-S), a derivative of EGCG esterified at the 4’ position with stearic acid, is able to …

Evaluation Of Fingerprint Content For Forensic Crime Scene Analysis And Drug Metabolite Detection, Erica Kathryn Brunelle

Legacy Theses & Dissertations (2009 - 2024)

With respect to criminal investigations, one key piece of evidence that often gets overlooked are fingerprints. For years, fingerprint samples have been believed to be useful only for matching purposes using their unique ridges, shapes, and sizes. With the rapid growth of forensic science, it has become evident that the development of fingerprint analysis has been stagnant. The traditional approach has been advantageous for the identification of many individuals; however, many fingerprint samples have been labeled “unusable” due to smudging, smearing, or any one of a myriad of reasons that could cause inconclusive matches. These samples can, however, still be …

Sers For Protein Detection At A Single Molecule Level For Developing A New Medical Diagnostics Platform, Lamyaa Almehmadi

Legacy Theses & Dissertations (2009 - 2024)

A two-step process of protein detection at a single molecule level using Surface Enhanced Raman Spectroscopy (SERS) was developed as a new platform for medical diagnostics in this proof-of-concept study. First, a protein molecule was bound to a linker in the bulk solution and then this adduct was chemically reacted with the SERS substrate. Traut’s Reagent (TR) was used to thiolate Bovine serum albumin (BSA) in solution followed by chemical cross linking to a gold surface through a sulfhydryl group. A Glycine-TR adduct was used as a control sample to identify the protein contribution to the SER spectra. Gold SERS …

Defining And Harnessing Nature's Selection Of Geranylation In Rna Modification, Phensinee Haruehanroengra

Legacy Theses & Dissertations (2009 - 2024)

Natural RNAs utilize extensive chemical modifications to diversify their structures and functions. Geranylated-2-thiouridine is a special hydrophobic tRNA modification that has been discovered very recently in several bacteria, namely E. coli, E. aerogenes, P. aeruginosa and S. typhimurium by Liu group. It has been found as a post-transcription modification on the wobble position of anticodon of tRNAs specific for glutamic acid, glutamine and lysine. Geranylated-tRNA was shown to correct the frameshifting during the translation of E. coli. However, the reason of the existing of the modification is still largely unclear. To understand why nature incorporates such a hydrophobic group in …

Saliva As A Diagnostic Biological Fluid And The Human Salivary Proteome, Jessica Ghassan Emsies

Legacy Theses & Dissertations (2009 - 2024)

Saliva is a unique biologic fluid that contains a varying spectrum of proteins, nucleic acids, electrolytes, and hormones.31 It is an exocrine secretion of the salivary glands which is hypotonic in nature with a pH of 7.2-7.4.31 Saliva plays an important role in the oral cavity.33 It lubricates, hydrates, and bathes the oral cavity, therefore, aiding speech and mastication.33 Saliva forms a barrier on the teeth, protects against demineralization, and aids in remineralization.33 Saliva is required for chewing and food bolus preparation, it contains enzymes necessary for digestion, and mediates the sense of taste.33 It also helps wound healing and …

Robert J. Lefkowitz And Discovery Of The G-Protein-Coupled Receptor Family, Clarence Lee

Natural Sciences Student Research Presentations

This poster for the Natural Sciences Poster Session at Parkland College features Dr. Robert J. Lefkowitz, 2012 Nobel Prize in Chemistry winner (with Brian Kobilka) for their research on G-protein-coupled receptors, proteins in the plasma membrane that allow for the transmission of information through the membrane and into the cell. This research was to impact the development of medications that target these receptors, such as SSRIs.

Functional Characterization Of Accessory Proteins And Novel Activities In Direct And Indirect Trna Aminoacylation, Udumbara Menike Rathnayake

Wayne State University Dissertations

Indirect tRNA aminoacylation is essential for most bacteria and archaea, particularly when these species do not have genes encoding asparaginyl- and/or glutaminyl-tRNA synthetase (AsnRS and GlnRS). In the absence of AsnRS, the first step in Asn-tRNAAsn synthesis involves misacylation of tRNAAsn with aspartate to produce Asp-tRNAAsn; this reaction is catalyzed by a non-discriminating aspartyl-tRNA synthetase (ND-AspRS). Subsequently, in bacteria, an amidotransferase called GatCAB converts Asp-tRNAAsn to Asn-tRNAAsn. An analogous, two-step processes exist to produce Gln-tRNAGln. In this case, a non-discriminating glutamyl-tRNA synthetase (ND-GluRS) misacylates tRNAGln to produce Glu-tRNAGln, which is then converted to Gln-tRNAGln by GatCAB. The central hub of …

Toward An Enzyme-Coupled, Bioorthogonal Platform For Methyltransferases: Probing The Specificity Of Methionine Adenosyltransferases, Tyler D. Huber

Theses and Dissertations--Pharmacy

Methyl group transfer from S-adenosyl-l-methionine (AdoMet) to various substrates including DNA, proteins, and natural products (NPs), is accomplished by methyltransferases (MTs). Analogs of AdoMet, bearing an alternative S-alkyl group can be exploited, in the context of an array of wild-type MT-catalyzed reactions, to differentially alkylate DNA, proteins, and NPs. This technology provides a means to elucidate MT targets by the MT-mediated installation of chemoselective handles from AdoMet analogs to biologically relevant molecules and affords researchers a fresh route to diversify NP scaffolds by permitting the differential alkylation of chemical sites vulnerable to NP MTs that are unreactive to …

Molecular Level Comparison Of Water Extractives Of Maple And Oak With Negative And Positive Ion Esi Ft-Icr Mass Spectrometry, Zhongqi He, Rachel L. Sleighter, Patrick G. Hatcher, Shasha Liu, Fengchang Wu, Haixuan Zou, O. Modesto Olanya

Chemistry & Biochemistry Faculty Publications

Soluble extractives in wood function to protect living trees from destructive agents and also contribute to wood color and fragrance. Some extractive components have biological activities with medical applications. They also play important roles in wood processing and related applications. To increase the knowledge of wood chemistry, maple and oak were extracted by water. Ultraviolet/visible (UV/vis) spectroscopy indicated the presence of a phenolic compound, resorcinol, in maple extractives having higher molecular mass and more aromatic components than oak extractives. Negative and positive electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR-MS) identified thousands of formulas in the two …

Condensation And Polymerization Explain The Humification Of Lignin Into Aliphatic And Aromatic Structures In Soil, Patrick G. Hatcher, Hongmei Chen, Seyyedhadi Khatami, Derek C. Waggoner

Chemistry & Biochemistry Faculty Publications

Soil organic matter (SOM) constitutes a global reservoir of carbon that is more than twice that of either atmospheric carbon or aquatic carbon; however, the manner in which it forms from degraded plant biomass is poorly understood. Some have recently questioned whether plant biomass is involved directly in SOM formation and suggest that it is microbial carbon that constitutes the main source of stable SOM. Such a view implies that above and below ground plant biomass is rapidly decomposed and mineralized. This view contrasts significantly with traditional ones that involve the transformation of plant biomass to recalcitrant humic materials fueled …

The Dynamic Nature And Biophysical Characterization Of Isu1, Fe-S Cluster Assembly Scaffold Protein In Saccharomyces Cerevisiae, And Its Significance To Human Disease, Brianne Elizabeth Lewis

Wayne State University Dissertations

Mitochondrial Fe-S cluster biosynthesis is accomplished within yeast utilizing the biophysical characteristics of the “Isu1” scaffold protein. As a member of a highly homologous protein family, Isu1 has sequence conservation with orthologs and a conserved ability to assemble [2Fe-2S] clusters. Regardless of species, scaffold orthologs can exist in both “disordered” and “structured” conformations and is directly related to conformations utilized during Fe-cofactor assembly. During assembly, the scaffold directs the delivery and the utilization of both Fe(II) and sulfide substrates in order to produce [2Fe-2S] clusters, however Zn(II) binding can alter the activity of the scaffold with stabilizing the protein in …

Thermostability And Excision Activity Of Polymorphic Forms Of Hogg1, Kathryn Mouzakis

Chemistry and Biochemistry Faculty Works

Objectives: Reactive oxygen species (ROS) oxidize guanine residues in DNA to form 7,8-dihydro-oxo-2′-deoxyguanosine (8oxoG) lesions in the genome. Human 8-oxoguanine glycosylase-1 (hOGG1) recognizes and excises this highly mutagenic species when it is base-paired opposite a cytosine. We sought to characterize biochemically several hOGG1 variants that have been found in cancer tissues and cell lines, reasoning that if these variants have reduced repair capabilities, they could lead to an increased chance of mutagenesis and carcinogenesis. Results: We have over-expressed and purified the R46Q, A85S, R154H, and S232T hOGG1 variants and have investigated their repair efficiency and thermostability. The hOGG1 variants showed …

Green Chemistry In United States Science Policy, Emily Jarvis

Chemistry and Biochemistry Faculty Works

Although optimizing each of the Twelve Principles of Green Chemistry is necessary for achieving the greenest possible chemistry in the lab, there are additional creative ways to promote green chemistry not encompassed by these. Communicating to society the importance of green chemistry beyond the laboratory is essential. Of course, doing this effectively presents distinct challenges to those encountered when designing chemical syntheses. Here, I discuss several observations from my time working in federal science policy as an American Association for the Advancement of Science/American Chemical Society Congressional Science Fellow in the United States Senate. I suggest a practical science policy …

Near-Infrared Fluorescent Probes For Sensitive Determination Of Lysosomal & Mitochondrial Ph In Live Cells, Wafa Mazi

Dissertations, Master's Theses and Master's Reports

Varied intracellular pH levels are critical for various physiological processes such as enzymatic activity, cell proliferation and apoptosis, ion transport, and muscle contraction. Cellular compartments, like lysosomes, must retain an acidic environment (pH ~ 4.5) to activate hydrolytic enzymes necessary for the breakdown of large biomolecules. Another cellular organelle, the mitochondria, provides the cell with energy and must retain an alkalis environment (pH ~ 8.0) for proper function. Substantial lysosomal and mitochondrial pH deviation is associated with cellular dysfunction and disease. Therefore, the precise detection of lysosomal and mitochondrial pH is essential to provide a better understanding of cellular physiological …