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Hinge Sequence Elements In Epithelial Cadherin Form And Function, Jessica Elizabeth Barnett Jan 2017

Hinge Sequence Elements In Epithelial Cadherin Form And Function, Jessica Elizabeth Barnett

Honors Theses

Cadherins play the vital role of mediating cell-cell adhesion in properly functioning tissues of the human body. Malfunction of these adherent cells can lead to drastic consequences like cancer metastasis. Thus, it is imperative to ensure the functionality of the molecular mechanism that drives these adhesive interactions. Of the various types, our studies specifically focused on the structure and function of the 'hinge region' in epithelial cadherin. This 'hinge region', composed of amino acid residues C9, P10, and E11, was of particular interest because it is the site of strand-swapped dimerization. The residues P10 and E11 are conserved within the …


A Raman Spectroscopic And Computational Study On The Effects Of Electron Withdrawing Groups On Halogen Bonding, Katelyn Allen Jan 2017

A Raman Spectroscopic And Computational Study On The Effects Of Electron Withdrawing Groups On Halogen Bonding, Katelyn Allen

Honors Theses

Here, the effects of individual electron withdrawing groups on halogen bond strength are investigated using Raman spectroscopy and electronic structure calculations. Halogen bonding is a unique and relatively unexplored noncovalent interaction that has recently garnered considerable attention due to its applications in materials development. When a halogen, such as chlorine, bromine, or iodine, accepts electron density from a Lewis base such as the nitrogen of pyridine a halogen bond arises. The anisotropic distribution of electron density about a covalently bound halogen, also known as the σ-hole, plays a significant role in halogen bond formation. The magnitude of the electropositive region …


A Study Of The Hydrophobic Interactions Between Twenty-Three Cb1 Selective Jwh Compounds And An Active-State Cb1 Receptor Model To Discover Key Structural Features Of The Jwh Compounds And Key Protein Residues Of The Cb1 Receptor, Lyncyn Louise Reliquias Jan 2017

A Study Of The Hydrophobic Interactions Between Twenty-Three Cb1 Selective Jwh Compounds And An Active-State Cb1 Receptor Model To Discover Key Structural Features Of The Jwh Compounds And Key Protein Residues Of The Cb1 Receptor, Lyncyn Louise Reliquias

Honors Theses

Synthetic cannabinoids, commonly found in Spice, have recently become a popular substitute for marijuana as they have similar effects to THC, the most powerful constituent of marijuana. Additionally, they are increasingly becoming a source of drug abuse as they cannot be detected with normal drug test screenings. This study specifically analyzed a total of twenty-three CB1 selective JWH compounds and their hydrophobic interactions with an active-state CB1 receptor model. The ligands were categorized per their structural similarities, and this study was aimed to find patterns within each structural moiety that would lead to the discovery of key structural features and/or …


Photophysical Characterization Of Newly-Synthesized Emissive Materials, Rachael Abigayle Nelson Jan 2017

Photophysical Characterization Of Newly-Synthesized Emissive Materials, Rachael Abigayle Nelson

Honors Theses

One key element in chemistry is understanding the chemical properties of a molecule so that its interactions with itself, other atoms or molecules, or its environment is well known. This knowledge alone allows the chemist to innovate and invent and thereby change the world. Light surrounds and sustains our lives; thus it is vital to understand how light interacts with common and newly synthesized materials. In this thesis the photophysical properties of newly synthesized materials will be discussed to give an overview of the many ways in which light interacts with the chemical materials composing our everyday lives. General photophysical …


Investigating Stress Response Across Integrated Biological Systems, Alice A. Han Jan 2017

Investigating Stress Response Across Integrated Biological Systems, Alice A. Han

Graduate Theses, Dissertations, and Problem Reports (ETD)

The impact that a stressor has on a living system, whether it is on a cellular, organ, or even a whole organism level, can affect the overall health of the system. Monitoring the biochemical response resulting from a stressful experience offers insight into the numerous potential outcomes ranging on the spectrum of survival and death. Accessing this information not only provides a heightened understanding of the biochemical adaptions that occur, but also allows for the development of prediction models (to assess prospective influences of the stressor) or potential therapeutic treatments (to alleviate adverse effects) using measurable, quantifiable, and comparable metrics. …


Functional And Mechanistic Insight Into The Role Of Atg9a In Autophagy, Vajira Kaushalya Weerasekara Jan 2017

Functional And Mechanistic Insight Into The Role Of Atg9a In Autophagy, Vajira Kaushalya Weerasekara

Theses and Dissertations

The bulk degradative process of macroautophagy requires the dynamic growth of autophagosomes, which carry cellular contents to the lysosome for recycling. Atg9A, a multi-pass transmembrane protein, is an apical regulator of autophagosome growth, yet its regulatory mechanism remains unclear. Our work suggests that hypoxia (low glucose and oxygen) triggers a rearrangement of the small adapter protein 14-3-3ζ interactome. Our data suggest that the localization of mammalian Atg9A to autophagosomes requires phosphorylation on the C terminus of Atg9A at S761, which creates a 14-3-3z docking site. Under basal conditions, this phosphorylation is maintained at a low level and is dependent on …


Caffeine Used As A Tracer Of Wastewater Contamination In South Florida, Stephanie Spence Jan 2017

Caffeine Used As A Tracer Of Wastewater Contamination In South Florida, Stephanie Spence

Honors Program Theses

In this study, a method was developed to analyze caffeine levels of water samples collected in Miami, Florida. The method was used to determine caffeine concentrations in reclaimed water samples and environmental water samples using on-line solid phase extraction (SPE) high pressure liquid chromatography (HPLC) high resolution mass spectrometry (HRMS). The rising use and disposal of pharmaceuticals and personal care products are becoming a concern as contaminants increasingly enter lakes, streams, and rivers without proper removal by traditional wastewater treatment processes. Caffeine may be used as a chemical tracer to indicate the presence of contamination in water samples and to …


Thermostability Of The Coating, Antigen And Immunostimulator In An Adjuvanted Oral Capsule Vaccine Formulation, Stephanie Longet, Vincenzo Aversa, Daire O'Donnell, Joshua Tobias, Monica Rosa, Jan Holmgren, Ivan Coulter, Ed Lavelle Jan 2017

Thermostability Of The Coating, Antigen And Immunostimulator In An Adjuvanted Oral Capsule Vaccine Formulation, Stephanie Longet, Vincenzo Aversa, Daire O'Donnell, Joshua Tobias, Monica Rosa, Jan Holmgren, Ivan Coulter, Ed Lavelle

Articles

Oral vaccines present an attractive alternative to injectable vaccines for enteric diseases due to ease of delivery and the induction of intestinal immunity at the site of infection. However, susceptibility to gastrointestinal proteolysis, limited transepithelial uptake and a lack of clinically acceptable adjuvants present significant challenges. A further challenge to mass vaccination in developing countries is the very expensive requirement to maintain the cold chain. We recently described the effectiveness of a Single Multiple Pill® (SmPill®) adjuvanted capsule approach to enhance the effectiveness of a candidate enterotoxigenic Escherichia coli (ETEC) oral vaccine. Here it was demonstrated that this delivery system …


Graphene Toxicity As A Double-Edged Sword Of Risks And Exploitable Opportunities: A Critical Analysis Of The Most Recent Trends And Developments, Yuri Volkov, Jennifer Mcintyre, Adriele Prina-Mello Jan 2017

Graphene Toxicity As A Double-Edged Sword Of Risks And Exploitable Opportunities: A Critical Analysis Of The Most Recent Trends And Developments, Yuri Volkov, Jennifer Mcintyre, Adriele Prina-Mello

Articles

Increased production volumes and a broadening application spectrum of graphene have raised concerns about its potential adverse effects on human health. Numerous reports demonstrate that graphene irrespective of its particular form exerts its effects on a widest range of living organisms, including prokaryotic bacteria and viruses, plants, micro-and macro-invertebrates, mammalian and human cells and whole animals in vivo. However, the available experimental data is frequently a matter of significant divergence and even controversy. Therefore, we provide here a critical analysis of the most recent (2015-2016) reports accumulated in the graphene-related materials biocompatibility and toxicology field in order to elucidate the …


Design, Cloning, And Expression Of Rat Preptin And Alanine Analogs, Jahbo M. Love Jan 2017

Design, Cloning, And Expression Of Rat Preptin And Alanine Analogs, Jahbo M. Love

Theses and Dissertations

Alanine scanning mutagenesis was employed to determine the structural epitopes of preptin; a newly discovered polypeptide found on the proinsulin-like growth factor II. The alanine scanning mutagenesis was accomplished by the use of, cloning, affinity chromatography, gel electrophoresis, gene sequencing, and mass spectra. However, due to inconclusive results, more research is required before the epitopes can be elucidated.


Self-Assembled Architecture Of Natural Organic Matter, Cynthia Johnson-Edler Jan 2017

Self-Assembled Architecture Of Natural Organic Matter, Cynthia Johnson-Edler

Electronic Theses and Dissertations

This investigation focuses on the determination of the architecture of the natural organic matter (NOM) contained within a soft coal-like material, an agricultural soil and a peat material. NOM has been extracted from bulk materials, fractionated, reassembled, then characterized by 13C Solid State NMR, Pulsed-Field Gradient NMR (PFG-NMR), and Small Angle Neutron Scattering (SANS). Interpretation of the data obtained by SANS has established that the majority of the components of NOM are mass fractals in solution and surface fractals in the solid state. Surface-to-volume ratios calculated with PFGNMR data indicate the NOM components studied have varying disk-like shapes. These …


Synthesis And Fluorescent Properties Of A New Flavonoid Compound, Ashley L. Ingle Jan 2017

Synthesis And Fluorescent Properties Of A New Flavonoid Compound, Ashley L. Ingle

Williams Honors College, Honors Research Projects

Flavonoids are highly luminescent compounds that are used in diagnosing and treating certain diseases.They are composed of two aromatic rings (ring A and ring B) and a six-membered heterocyclic pyran ring (ring C) that contains a carbonyl and hydroxyl group, which are responsible for unique photophysical characteristics associated with flavonoids. The target flavonoids (compound 1, or 1, and compound 2 or 2) were synthesized, purified and characterized by NMR spectroscopy. The photophysical properties of the flavonoid were investigated in varying solvents by using UV-vis and fluorescence spectroscopy. Such properties include Excited State Intramolecular Proton Transfer (ESIPT), Intramolecular Charge …


Use Of The Novel Derivatizing Agent 1,8-Diaminonapthalene With The Cip10 Sampler To Measure 4,4'-Methylene Diphenyl Diisocyanate Atmospheres, Silvia Puscasu, Simon Aubin, Philippe Sarazin, Lucile Richard, Mark Spence, Sébastien Gagné Jan 2017

Use Of The Novel Derivatizing Agent 1,8-Diaminonapthalene With The Cip10 Sampler To Measure 4,4'-Methylene Diphenyl Diisocyanate Atmospheres, Silvia Puscasu, Simon Aubin, Philippe Sarazin, Lucile Richard, Mark Spence, Sébastien Gagné

Études primaires

DAN is a novel derivatizing agent for isocyanate sampling which targets total reactive isocyanate group (TRIG). Field evaluations have been conducted for 4,4’-Methylene diphenyl diisocyanate (MDI) sampling using DAN as the derivatizing agent in a CIP10. The perimidone formed, selective of TRIG, was analyzed in laboratory by liquid chromatography coupled to tandem mass spectrometry. Workplaces using MDI-based polyurethane spray foam and MDI wood product binder were studied. Each study compared the data obtained between the CIP10/DAN, the CIP10/MP, and a reference method. As a first evaluation, the CIP10/DAN sampled simulated MDI spray foam atmosphere in parallel with impingers (reference method) …


The Anticancer Effects Of The Different Analogs Of Cysteine Deleted Tachyplesin On A549 Lung Cancer Cells, Nathan Riley Hendrickson Jan 2017

The Anticancer Effects Of The Different Analogs Of Cysteine Deleted Tachyplesin On A549 Lung Cancer Cells, Nathan Riley Hendrickson

Master's Theses and Doctoral Dissertations

It has been previously shown that cysteine-deleted tachyplesin (CDT) and its many analogs display antibacterial effects. However, little has been said about its possible anticancer effects and which analogs serve as the best inhibitors of the growing cancer cells. This research focused on CDT and four of its analogs: All D-CDT, Reverse DCDT, Reverse CDT, and Serine-Control CDT. MTT assays against the A549 adenocarcinoma lung cancer cell line showed All D-CDT to be the most effective analog in preventing cancer cell growth. Hyaluronidase and apoptosis assays were performed to better understand the mechanism by which the All D-CDT is preventing …


A Miniaturized Spectrophotometric In Situ Ph Sensor For Seawater, Reuben C. Darlington Jan 2017

A Miniaturized Spectrophotometric In Situ Ph Sensor For Seawater, Reuben C. Darlington

Graduate Student Theses, Dissertations, & Professional Papers

Since the Industrial Revolution, the world's oceans have absorbed increasing amounts of CO2 and the resultant changes to the marine carbonate chemical system have reduced the pH by > 0.1 units (~ 30%) in surface waters. This acidification of the oceans has many far reaching impacts on marine life and there is great need of quality instrumentation to assess and follow the changing carbonate system. This MIS project aims to develop a low cost pH sensor with high precision and accuracy for open sea measurements with special emphasis on reduced size and cost. Design effort is based on the commercially available …


Raman Spectroscopy Capabilities Of The Cbex Handheld Raman Instrument, Samantha Ingenito Jan 2017

Raman Spectroscopy Capabilities Of The Cbex Handheld Raman Instrument, Samantha Ingenito

Chemistry

Raman spectroscopy is a reliable, nondestructive method of identifying and distinguishing between different types of biological fluids. However, forensic studies have been restricted to indoor desktop Raman instruments when it would be optimal if Raman spectroscopic analysis could be performed at a crime scene. The CBex Handheld Raman Instrument was developed as a portable tool that could perform Raman spectroscopy outside the lab. Unfortunately, the CBex cannot obtain viable spectra of biological fluids. The handheld was compared to the Renishaw invia Raman Microscope by quantifying the signal-to-noise ratio of each by acquiring Scotch tape spectra. The handheld has a significantly …


Detecting Haloacetic Acids Using Chromatography, Nathan Perinovic Jan 2017

Detecting Haloacetic Acids Using Chromatography, Nathan Perinovic

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.


The Stress Granule Transcriptome Reveals Principles Of Mrna Accumulation In Stress Granules, Sarah F. Mitchell Jan 2017

The Stress Granule Transcriptome Reveals Principles Of Mrna Accumulation In Stress Granules, Sarah F. Mitchell

Chemistry and Biochemistry Faculty Works

Stress granules are mRNA-protein assemblies formed from nontranslating mRNAs. Stress granules are important in the stress response and may contribute to some degenerative diseases. Here, we describe the stress granule transcriptome of yeast and mammalian cells through RNA-sequencing (RNA-seq) analysis of purified stress granule cores and single-molecule fluorescence in situ hybridization (smFISH) validation. While essentially every mRNA, and some noncoding RNAs (ncRNAs), can be targeted to stress granules, the targeting efficiency varies from <1% to >95%. mRNA accumulation in stress granules correlates with longer coding and UTR regions and poor translatability. Quantifying the RNA-seq analysis by smFISH reveals that only 10% of …


Metabolomic Profiling Of Chiari Malformation Type I: Comparison Of Bioinformatic Programs For Untargeted Analysis, Hunter W. Korsmo Jan 2017

Metabolomic Profiling Of Chiari Malformation Type I: Comparison Of Bioinformatic Programs For Untargeted Analysis, Hunter W. Korsmo

Williams Honors College, Honors Research Projects

Chiari Malformation Type I is a neurodegenerative trait that can result from disease or from acquiring. Metabolomic analysis was done on normal pressure hydrocephalous and Chiari CSF samples using LC-MS and multiple bioinformatic programs. After analysis from multiple programs, we were able to analyze the stringency in statistical algorithms done by each program and determined qualities that are shared between programs that offer multiple details. We identified dysregulation in glucuronated metabolites in CSF of Chiari versus NPH. Using LC-MS, we established the experimental MS/MS of glucuronic acid in attempt to identify similarities in mass-to-charge features primarily identified. We could not …


Toward The Synthesis Of Functionalized Poly (Ether Ether Ketone): Monitoring The Meta-Fluorine Displacement In 3,5,4’-Trifluorobenzophenone, Giovanni Covarrubias Jan 2017

Toward The Synthesis Of Functionalized Poly (Ether Ether Ketone): Monitoring The Meta-Fluorine Displacement In 3,5,4’-Trifluorobenzophenone, Giovanni Covarrubias

Browse all Theses and Dissertations

The synthesis of functionalized, linear poly (ether ether ketone), tailored to be semi-crystalline and soluble in a variety of organic-solvents was explored. Nucleophilic aromatic substitution was a chemical reaction method used to condense 3,5,4’-trifluorobenzophenone (TFK) with four different phenols at its para-positioned carbon-fluorine site: 4-methoxyphenol, 3-aminophenol, 4-bromophenol, and m-cresol. Further poly-condensation of functionalized TFK occurred at the meta-positioned carbon-fluorine sites with 4,4’-Bis[4-hydroxyphenoxy] benzophenone (Big A2) and 4,4’-difluorobenzophenone at molar equivalents of 1 to 0.5, respectively. The reaction afforded products that became insoluble in solvents needed for nuclear magnetic resonance spectroscopic (e.g. DMSO-d6) analysis. The lack of desirable compounds compelled the …


Investigating Potential Pollutant Sources Causing Lack Of Biodiversity In Lytle Creek And Indian Run, Amira Moayad Alsenbel Jan 2017

Investigating Potential Pollutant Sources Causing Lack Of Biodiversity In Lytle Creek And Indian Run, Amira Moayad Alsenbel

Browse all Theses and Dissertations

Limited macroinvertebrate biodiversity in Lytle Creek that runs through downtown Wilmington, Ohio has been documented over decades with the lowest in Lytle Creek at Sugar Grove Cemetery. Lytle Creek, a tributary of the Little Miami River, is a conduit for storm water and wastewater from an airport, downtown storm water with input from local businesses, and a wastewater treatment plant. This study was conducted to see if heavy metal pollution in the sediment, water quality, and Escherichia coli (E. coli) could be contributing factors in reduced macroinvertebrate populations. Eight sites were chosen for sediment sampling to measure trace metals. Mercury …


Antimicrobial Activity Of Fractionated Borohydride-Capped And Electrochemical Colloidal Silver, Marjorie M. Markopoulos Jan 2017

Antimicrobial Activity Of Fractionated Borohydride-Capped And Electrochemical Colloidal Silver, Marjorie M. Markopoulos

Browse all Theses and Dissertations

Silver nanoparticles (AgNPs) and ionic silver (Ag+) are known to be broad-spectrum antimicrobial agents. Recent studies show these agents may be an alternative to the most widely used drinking water disinfectant, chlorine. Chlorine is a toxic industrial chemical with a lethal concentration of 430 ppm after 30 minutes. Additionally, chlorine can react with naturally occurring materials to produce a number of disinfection byproducts such as chloroform and trihalomethanes. Some of these byproducts pose cancer risks in addition to other negative impacts to human health. These would be eliminated with the use of Ag+ or AgNPs. The main goal of this …


Efficient Integration Of Plasmonic And Excitonic Properties Of Metal And Semiconductor Nanostructures Via Sol-Gel Assembly, Dilhara Liyanage Jan 2017

Efficient Integration Of Plasmonic And Excitonic Properties Of Metal And Semiconductor Nanostructures Via Sol-Gel Assembly, Dilhara Liyanage

Theses and Dissertations

Research in nanoscience has gained noteworthy interest over the past three decades. As novel chemical and physical properties that are vastly different from extended solids are realized in nanosized materials, nanotechnology has become the center of attention for material in research community. Much to our amazement, investigations in the past two decades revealed that the nanocrystalline semiconductors are “THE PRIME CANDIDATES” to meet the growing energy demand, sensor development, cellular imaging and a number of other optoelectronic applications. Nonetheless, synthesis of nanostructures with control over physical parameters is not sufficient, yet assembling them into functional nanoarchitectures with unique and tunable …


Elucidation Of Protein Interactions And The Re-Tuning Of Porphyrin Electronics For Hydroxylases, Steven Charles Ratigan Jan 2017

Elucidation Of Protein Interactions And The Re-Tuning Of Porphyrin Electronics For Hydroxylases, Steven Charles Ratigan

Theses and Dissertations

Non-Ribosomal Peptide Synthetases (NRPSs) and their exogenous tailoring partners have been heavily studied but not in the context of non-cognate systems. Orf78, a dinuclear iron β-hydroxylase from the lysobacter pathway and homologous to CmlA from the chloramphenicol pathway, is used to test affinities for one native and two non-native T-domains. Results indicate that there is enough difference between Type I and Type II NRPS systems to disfavor common recognition motifs. Additionally, the β-hydroxylase P450sky, from the skyllamycin biosynthetic pathway, is used in conjunction with the NRPS ATdomain NikP1AT from the nikkomycin biosynthetic pathway, in lieu of the homolog P450nikQ. The …


Silylation-Based Kinetic Resolution Of 2-Arylcyclohexanols And Understanding Internal Chirality Transmission Via Circular Dichroism, Li Wang Jan 2017

Silylation-Based Kinetic Resolution Of 2-Arylcyclohexanols And Understanding Internal Chirality Transmission Via Circular Dichroism, Li Wang

Theses and Dissertations

This work described herein focuses on the silylation-based kinetic resolution methodology developed by the Wiskur group in 2011. It is a powerful method for the separation of a single enantiomer from a mixture of racemic secondary alcohols. Chapter one is a summary of the background and related works of this methodology.

In chapter two, the silylation-based kinetic resolution of various trans 2-arylcyclohexanols will be discussed by employing a p-isopropyl triphenylsilyl chloride as the derivatizing reagent with (-)-benzotetramisole as the catalyst. The diastereoselective and enantioselective of trans alcohols over the cis will be investigated and a facial one-pot reaction sequence will …


Criegee Intermediate-Hydrogen Sulfide Chemistry At The Air/Water Interface, Manoj Kumar, Jie Zhong, Joseph S. Francisco, Xiao Cheng Zeng Jan 2017

Criegee Intermediate-Hydrogen Sulfide Chemistry At The Air/Water Interface, Manoj Kumar, Jie Zhong, Joseph S. Francisco, Xiao Cheng Zeng

Xiao Cheng Zeng Publications

We carry out Born–Oppenheimer molecular dynamic simulations to show that the reaction between the smallest Criegee intermediate, CH2OO, and hydrogen sulfide (H2S) at the air/water interface can be observed within few picoseconds. The reaction follows both concerted and stepwise mechanisms with former being the dominant reaction pathway. The concerted reaction proceeds with or without the involvement of one or two nearby water molecules. An important implication of the simulation results is that the Criegee-H2S reaction can provide a novel non-photochemical pathway for the formation of a C–S linkage in clouds and could be a …


Metabolic Investigations Of The Molecular Mechanisms Associated With Parkinson’S Disease, Robert Powers, Shulei Lei, Annadurai Anandhan, Darrell D. Marshall, Bradley Worley, Ronald Cerny, Eric D. Dodds, Yuting Huang, Mihalis I. Panayiotidis, Aglaia Pappa, Rodrigo Franco Jan 2017

Metabolic Investigations Of The Molecular Mechanisms Associated With Parkinson’S Disease, Robert Powers, Shulei Lei, Annadurai Anandhan, Darrell D. Marshall, Bradley Worley, Ronald Cerny, Eric D. Dodds, Yuting Huang, Mihalis I. Panayiotidis, Aglaia Pappa, Rodrigo Franco

Robert Powers Publications

Parkinson’s disease (PD) is a neurodegenerative disorder characterized by fibrillar cytoplasmic aggregates of α-synuclein (i.e., Lewy bodies) and the associated loss of dopaminergic cells in the substantia nigra. Mutations in genes such as α -synuclein (SNCA) account for only 10% of PD occurrences. Exposure to environmental toxicants including pesticides and metals (e.g., paraquat (PQ) and manganese (Mn)) is also recognized as an important PD risk factor. Thus, aging, genetic alterations, and environmental factors all contribute to the etiology of PD. In fact, both genetic and environmental factors are thought to interact in the promotion of idiopathic PD, but the mechanisms …


Amino Acid Catabolism In Staphylococcus Aureus And The Function Of Carbon Catabolite Repression, Cortney R. Halsey, Shulei Lei, Jacqueline K. Wax, Mckenzie K. Lehman, Austin S. Nuxoll, Laurey Steinke, Marat Sadykov, Robert Powers, Paul D. Fey Jan 2017

Amino Acid Catabolism In Staphylococcus Aureus And The Function Of Carbon Catabolite Repression, Cortney R. Halsey, Shulei Lei, Jacqueline K. Wax, Mckenzie K. Lehman, Austin S. Nuxoll, Laurey Steinke, Marat Sadykov, Robert Powers, Paul D. Fey

Department of Chemistry: Faculty Publications

Staphylococcus aureus must rapidly adapt to a variety of carbon and nitrogen sources during invasion of a host. Within a staphylococcal abscess, preferred carbon sources such as glucose are limiting, suggesting that S. aureus survives through the catabolism of secondary carbon sources. S. aureus encodes pathways to catabolize multiple amino acids, including those that generate pyruvate, 2-oxoglutarate, and oxaloacetate. To assess amino acid catabolism, S. aureus JE2 and mutants were grown in complete defined medium containing 18 amino acids but lacking glucose (CDM). A mutation in the gudB gene, coding for glutamate dehydrogenase, which generates 2-oxoglutarate from glutamate, significantly reduced …


Nanomaterials As Stationary Phases And Supports In Liquid Chromatography: A Review, Sandya Beeram, Elliott Rodriguez, Suresh Doddavenkatanna, Zhao Li, Allegra Pekarek, Darin Peev, Kathryn Goerl, Gianfranco Trovato, Tino Hofmann, David S. Hage Jan 2017

Nanomaterials As Stationary Phases And Supports In Liquid Chromatography: A Review, Sandya Beeram, Elliott Rodriguez, Suresh Doddavenkatanna, Zhao Li, Allegra Pekarek, Darin Peev, Kathryn Goerl, Gianfranco Trovato, Tino Hofmann, David S. Hage

Department of Chemistry: Faculty Publications

The development of various nanomaterials over the last few decades has led to many applications for these materials in liquid chromatography (LC). This review will look at the types of nanomaterials that have been incorporated into LC systems and the applications that have been explored for such systems. A number of carbon-based nanomaterials and inorganic nanomaterials have been considered for use in LC, ranging from carbon nanotubes, fullerenes and nanodiamonds to metal nanoparticles and nanostructures based on silica, alumina, zirconia and titanium dioxide. Many ways have been described for incorporating these nanomaterials into LC systems. These methods have included covalent …


A Surface-Stabilized Ozonide Triggers Bromide Oxidation At The Aqueous Solution-Vapour Interface, Luca Artiglia, Jacinta Edebeli, Fabrizio Orlando, Shuzhen Chen, Ming-Tao Lee, Pablo Corral Arroyo, Anina Gilgen, Thorsten Bartels-Rausch, Armin Kleibert, Mario Vazdar, Marcelo Andrea Carignano, Joseph S. Francisco, Paul B. Shepson, Ivan Gladich, Markus Ammann Jan 2017

A Surface-Stabilized Ozonide Triggers Bromide Oxidation At The Aqueous Solution-Vapour Interface, Luca Artiglia, Jacinta Edebeli, Fabrizio Orlando, Shuzhen Chen, Ming-Tao Lee, Pablo Corral Arroyo, Anina Gilgen, Thorsten Bartels-Rausch, Armin Kleibert, Mario Vazdar, Marcelo Andrea Carignano, Joseph S. Francisco, Paul B. Shepson, Ivan Gladich, Markus Ammann

Department of Chemistry: Faculty Publications

Oxidation of bromide in aqueous environments initiates the formation of molecular halogen compounds, which is important for the global tropospheric ozone budget. In the aqueous bulk, oxidation of bromide by ozone involves a [Br•OOO−] complex as intermediate. Here we report liquid jet X-ray photoelectron spectroscopy measurements that provide direct experimental evidence for the ozonide and establish its propensity for the solution-vapor interface. Theoretical calculations support these findings, showing that water stabilizes the ozonide and lowers the energy of the transition state at neutral pH. Kinetic experiments confirm the dominance of the heterogeneous oxidation route established by this precursor …