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Full-Text Articles in Chemistry

Wastewater-Based Estimation Of Substances Discharged At The Rest Areas Along The State Highways In Kentucky, Katherine E. Gray, Eugene Shin, Tyler Whitt, Andrew Windhorst, Houston Hampton, Chris Delcher, Bikram Subedi Jan 2022

Wastewater-Based Estimation Of Substances Discharged At The Rest Areas Along The State Highways In Kentucky, Katherine E. Gray, Eugene Shin, Tyler Whitt, Andrew Windhorst, Houston Hampton, Chris Delcher, Bikram Subedi

Posters-at-the-Capitol

The availability of licit and illicit stimulants and its adverse consequences on public health has emerged as a major drug threat to communities in the United States. Despite several drug-involved traffic incidents along the interstate highways, this report represents the first comprehensive and quantitative report of drugs discharged at the rest areas along the interstate highways. In this National Institute of Justice-funded study, the amount of several discharged drugs focusing on stimulants but also including opioids and prescription antipsychotics are being measured in raw wastewater collected from five rest areas and a truck servicing facility using a state-of-the-art mass …


Investigation Of Metastable Low Dimensional Halometallates, Navindra Keerthisinghe, Matthew S. Christian, Anna A. Berseneva, Gregory Morrison, Vladislav V. Klepov, Mark D. Smith, Hans Conrad Zur Loye Jan 2022

Investigation Of Metastable Low Dimensional Halometallates, Navindra Keerthisinghe, Matthew S. Christian, Anna A. Berseneva, Gregory Morrison, Vladislav V. Klepov, Mark D. Smith, Hans Conrad Zur Loye

Faculty Publications

The solvothermal synthesis, structure determination and optical characterization of five new metastable halometallate compounds, [1,10-phenH][Pb3.5I8] (1), [1,10-phenH2][Pb5I12]·(H2O) (2), [1,10-phen][Pb2I4] (3), [1,10-phen]2[Pb5Br10] (4) and [1,10-phenH][SbI4]·(H2O) (5), are reported. The materials exhibit rich structural diversity and exhibit structural dimensionalities that include 1D chains, 2D sheets and 3D frameworks. The optical spectra of these materials are consistent with bandgaps ranging from 2.70 to 3.44 eV. We show …


Characterization Of Cyclopropyl Synthases Involved In The Maturation Of Ribosomally Synthesized And Posttranslationally Modified Peptides, Yi Lien Jan 2022

Characterization Of Cyclopropyl Synthases Involved In The Maturation Of Ribosomally Synthesized And Posttranslationally Modified Peptides, Yi Lien

Electronic Theses and Dissertations

Ribosomally synthesized and post-translationally modified peptides (RiPPs) are a large class of natural products with significant human health implications. RiPPs are synthesized from a genetically encoded precursor peptide that undergoes significant modifications by maturing enzymes, or maturases. Recently, radical-S-adenosylmethionine (rSAM) enzymes have emerged as an important family of RiPP maturases. rSAM enzymes have been shown to install ether, thioether, and carbon-carbon bonds on the precursor peptide. These modifications usually define the backbone structure of the mature RiPP. This thesis describes the characterization of a novel RiPP modification catalyzed by the radical S-adenosylmethionine enzyme TigE. TigE belongs to the TIG biosynthetic …


Lipophilic Probes For Cellular Ethylene Detection, Morgan R. Brown Jan 2022

Lipophilic Probes For Cellular Ethylene Detection, Morgan R. Brown

Electronic Theses and Dissertations

The structure of ethylene is simple, yet its biological effects are significant. When considering its role in biology it is almost exclusively regarded as a plant hormone. Research on ethylene from plants was progressed by several advancements in analytical instrumentation, from its discovery to elucidation of its signaling pathway. There is currently limited understanding of ethylene’s role in mammals, but evidence suggests that it may be a biomarker for oxidative stress! Additional tools and technology are crucial to study this surprising and important signaling role in mammals. Our group has developed molecular ethylene probes as a strategy to detect ethylene …


Cysteine-Tyrosine Crosslink Synthesis In Bf4112 From B. Fragilis, Alex Van Uffelen, Sophie Hruska, David Benson Jan 2022

Cysteine-Tyrosine Crosslink Synthesis In Bf4112 From B. Fragilis, Alex Van Uffelen, Sophie Hruska, David Benson

Summer Research

Redox-active crosslinked amino acids are a class of post-translational modifications that extend protein chemistry. These cofactors occur in fifteen known proteins with high resolution Xray crystallography as the primary method for confirmation. One of those proteins is cytochrome c oxidase (complex IV), where HisTyr (figure 1) is responsible for the high-valent oxidative intermediate in O2 reduction to 2H2O. Cys-Tyr was the first of these cofactors to be identified and is characterized in galactose oxidase (coordinated to a Cu ion) and cysteine dioxygenase (distal to a mononuclear non-heme iron ion).


Using Circular Dichroism Spectroscopy To Study Secondary Structure Of Horseradish Peroxidase: A Laboratory Experiment In Biochemistry, Shemaiah Kamran, Sarah E. Bultje, Kumar Sinniah Jan 2022

Using Circular Dichroism Spectroscopy To Study Secondary Structure Of Horseradish Peroxidase: A Laboratory Experiment In Biochemistry, Shemaiah Kamran, Sarah E. Bultje, Kumar Sinniah

Summer Research

  • We present a laboratory experiment in biochemistry to study the Far-UV Visible secondary structure of a protein (horseradish peroxidase, HRP) that can be adapted for a single-session laboratory experiment or a multiple-session laboratory project.
  • A Circular Dichroism (CD) spectrometer provides structural information of proteins as a function of environmental changes such as pH and temperature. We present secondary structural information for the protein, horseradish peroxidase, at pH 3 and pH 7 in the temperature range 30-80° C in phosphate buffered solution (PBS).
  • HRP has many applications in biochemistry and biotechnology. It is frequently used as a reporter enzyme in diagnostics …


Inflammatory Response To Sleep Fragmentation In Skeletal, Cardiac, And Smooth Muscle Tissues In Female Mice, Patton Allen Jan 2022

Inflammatory Response To Sleep Fragmentation In Skeletal, Cardiac, And Smooth Muscle Tissues In Female Mice, Patton Allen

Mahurin Honors College Capstone Experience/Thesis Projects

Sleep is a critical process that the body undergoes. When sleep is interrupted, so that an individual is awakened for some period before going back into sleep, the sleep can be described as fragmented. Studies in the past have shown that sleep fragmentation (SF) promotes an inflammatory environment, especially in the brain and peripheral tissue. However, studies have not been conducted to observe inflammatory responses in muscle. To examine this, C57BL/6J female mice were subjected to either a control group (no SF) or a SF group which involved using an automated SF chamber to disrupt sleep every 2 min over …


Affinity Of Cadmium Versus Zinc For The Carbonic Anhydrase Active Site, Rachel Phan Jan 2022

Affinity Of Cadmium Versus Zinc For The Carbonic Anhydrase Active Site, Rachel Phan

Honors Scholars Collaborative Projects

Cadmium is a heavy metal found in tobacco plants, nickel-cadmium batteries, and as a byproduct of metal mining. The similarities between the properties of zinc ions and cadmium ions in proteins due to their 2+ charges may cause displacement of zinc by cadmium if encountered and has been shown to do so in several transcription factors. Cadmium’s ability to replace zinc- a metal found in around 3,000 human proteins- is a cause for concern, especially due to its toxicity, long half-life in the body, and larger size.

Carbonic anhydrase is an important metalloprotein protein that relies on a central zinc(II) …


Investigating Spatiotemporal Kinetics, Dynamics, And Mechanism Of Exosome Release, Anarkali Mahmood Jan 2022

Investigating Spatiotemporal Kinetics, Dynamics, And Mechanism Of Exosome Release, Anarkali Mahmood

Electronic Theses and Dissertations

Exosomes are small lipid-based vesicles that can carry biomolecules from one cell to another. While exosomes are crucial to maintain homeostasis in healthy cells, they are exploited by unhealthy cells to aid disease progression. Exosomes likely facilitate disease progression via the transfer of disease-causing biomolecules from unhealthy to healthy cells. Exosomes are generated in Multivesicular endosomes (MVEs) and are then secreted into the extracellular space to travel to other cells. Despite being a crucial step, very little is known about exosomes release mechanism and dynamics. To further our understanding of exosomes, specifically their secretion, my work has focused on investigating …


Kinase-Catalyzed Labeling To Identify Kinase-Substrate Pairs Using Γ-Phosphate Modified Atp Analogs, Rachel Beltman Jan 2022

Kinase-Catalyzed Labeling To Identify Kinase-Substrate Pairs Using Γ-Phosphate Modified Atp Analogs, Rachel Beltman

Wayne State University Dissertations

Post-translational modifications (PTMs) are responsible for a variety of cellular processes. One such PTM is protein phosphorylation, which is catalyzed by kinases. Kinase enzymes play important roles in cellular signaling pathways, but dysregulation of kinase-mediated events results in the formation of diseases, which make kinases favorable drug targets. To uncover the role kinases play in the development of diseases, kinase-mediated cellular events need to be better understood. The current gap in the field is the lack of tools available to identify the kinase that is responsible for specific phosphorylation events within the cell. To improve the gap in the field, …


Evaluation Of A Shortened Redon Fit Test Protocol For Half-Mask Respirators, Olivia Dawson, Riley Duncan, Leshan J. Kimbrough Jan 2022

Evaluation Of A Shortened Redon Fit Test Protocol For Half-Mask Respirators, Olivia Dawson, Riley Duncan, Leshan J. Kimbrough

Scholar's Day

The purpose of this study was to investigate whether a shortened REDON method is as effective and accurate compared to the reference method when measuring respirator fit for elastomeric half-mask respirators using the Quantifit® CNP instrument.


Investigation Of Catalysis Of Nitration By Cytochrome P450s, Lannika Johnson Jan 2022

Investigation Of Catalysis Of Nitration By Cytochrome P450s, Lannika Johnson

Honors Undergraduate Theses

TxtE is a protein related to cytochrome P450 enzymes, which catalyze a number of reactions that typically involve oxygen and not nitrogen. It has been discovered that TxtE can nitrate tryptophan through an unusual reaction in which it uses nitric oxide (NO) as a nitrogen donor to install the nitro group despite NO typically being considered toxic to bacteria. This project will determine if all cytochromes P450 can catalyze nitration as long as they are given NO. This will have an impact on understanding drug delivery and metabolism for which nitration is important.


Whole Exome Sequencing Identifies A Novel Mutation In Aspm And Ultra-Rare Mutation In Cdk5rap2 Causing Primary Microcephaly In Consanguineous Pakistani Families, Ehtisham Ul Haq Makhdoom, Haseeb Anwar, Shahid Mahmood Baig, Ghulam Hussain Jan 2022

Whole Exome Sequencing Identifies A Novel Mutation In Aspm And Ultra-Rare Mutation In Cdk5rap2 Causing Primary Microcephaly In Consanguineous Pakistani Families, Ehtisham Ul Haq Makhdoom, Haseeb Anwar, Shahid Mahmood Baig, Ghulam Hussain

Department of Biological & Biomedical Sciences

Background & objectives: Primary Microcephaly (MCPH) is a rare neurogenetic disease, manifesting congenitally reduced head circumference and non-progressive intellectual disability (ID). To date, twenty-eight genes with biallelic mutations have been reported for this disorder. The study aimed for molecular genetic characterization of Pakistani families segregating MCPH.
Methods: We studied two unrelated consanguineous families (family A and B) presenting >2 patients with diagnostic symptoms of MCPH, born to asymptomatic parents. We employed whole-exome sequencing (WES) of probands to find putative causal mutations. The candidate variants were further confirmed and analyzed for co-segregation by Sanger sequencing of all available members of each …


Extending Plasma Proteome Coverage To Enable Biomarker Discovery, Jordan Bruce Burton Jan 2022

Extending Plasma Proteome Coverage To Enable Biomarker Discovery, Jordan Bruce Burton

Wayne State University Dissertations

Two features make plasma a valued source of health information: First, plasma contains secreted proteins from all tissues in the body and can, therefore, provide information about the health status of all tissues. Second, plasma is available in large quantity using a minimally invasive procedure that is well tolerated. The status of plasma as a valued source of health information is matched by the difficulty in extracting proteome information from the samples. Using state of the art instrumentation a standard analysis of plasma yields quantitative information on approximately 300 proteins. Extreme fractionation strategies coupled with increased mass spectrometry time extends …


Introducing An H113a Mutation Into Atg10 Y73q To Reduce Autophagic Activity And Understand The Effect Of Atg On Autophagosome Size And Number, Konrad L. Lautenschlager Jan 2022

Introducing An H113a Mutation Into Atg10 Y73q To Reduce Autophagic Activity And Understand The Effect Of Atg On Autophagosome Size And Number, Konrad L. Lautenschlager

Senior Honors Theses and Projects

Autophagy is an essential recycling process that occurs within eukaryotic cells, however, the individual functions of the current thirty-two known autophagic proteins are not yet entirely understood. At this time, it is known that the autophagic protein Atg7 works upstream of both Atg3 and Atg10. Atg3 is affected by Atg7 and allows for the attachment of Atg8 and the lipid PE which is part of the autophagosome membrane. The Atg10 pathway is also affected by Atg7 but attaches Atg12 to Atg5 which upregulates the function of Atg3 and ultimately Atg8 lipidation. These protein interactions are necessary for forming autophagosomes, large …


Chromatographic Studies Of Some Hormone And Metabolic Modulators Used For Doping In Sports, Ruth Marie Speidel Jan 2022

Chromatographic Studies Of Some Hormone And Metabolic Modulators Used For Doping In Sports, Ruth Marie Speidel

Online Theses and Dissertations

The World Anti-Doping Agency (WADA) is an international agency that monitors the use of Performance Enhancing Drugs (PEDs) in sports; their mission is “to lead a collaborative worldwide movement for doping-free sport” (Who We Are, 2022). For this mission, the WADA needs quick, sensitive, reproducible, and accurate methods for analyzing athletes’ biological fluids for possible PEDs. This research focuses on developing and validating simple, sensitive, rapid, and reliable gas chromatography- mass spectrometry (GC-MS) methods for the analysis of two hormone and metabolic modulators, toremifene and trimetazidine. Previously, there has been limited GC-MS methods used to analyze toremifene and trimetazidine. Quantification …


Establishing A Biochemical System For The Purification And Atpase Activity Of Gst-Dbp5, Sarah R. Utley, Rachel E. Rigsby Phd, Rebecca L. Adams Phd Jan 2022

Establishing A Biochemical System For The Purification And Atpase Activity Of Gst-Dbp5, Sarah R. Utley, Rachel E. Rigsby Phd, Rebecca L. Adams Phd

Science University Research Symposium (SURS)

The export of mRNA out of the nucleus is a crucial step for eukaryotic gene expression. The export of mRNA transcripts is aided by Mex67, which allows export through the nuclear pore complex doorways in the nuclear envelope. Once out of the nucleus, a protein known as Dbp5, bound to ATP, Gle1, and Nup42 aids in the directionality of mRNA export by helping remove Mex67 from the mRNA strand. Following interaction with RNA, Dbp5 then hydrolyzes ATP so that it unbinds the mRNA, allowing for enzyme recycling. Previous efforts worked towards the purification of Dbp5, but the attempts were unsuccessful …


Biomimetic Synthesis Of Palladium Nanoparticles For Catalytic Application, Emily A. Groover Jan 2022

Biomimetic Synthesis Of Palladium Nanoparticles For Catalytic Application, Emily A. Groover

College of Graduate Studies: Theses & Dissertations

The synthesis of palladium nanoparticles (Pd NPs) using materials-directed peptides is a novel, nontoxic approach which exerts a high level of control over the particle size and shape. This biomimetic technique is environmentally benign, featuring nonhazardous ligands and ambient conditions. Nanoparticles are extremely reactive catalysts, boasting a large surface-to-volume ratio when compared to their bulk counterparts. The rational design of these nanoparticles using peptides has been very successful in aqueous environments, but no research has been done to apply it in organic systems. As such, the biomimetic synthesis of Pd NPs in an organic system is here investigated, with ethanol …


Calcification, Dissolution And Test Properties Of Modern Planktonic Foraminifera From The Central Atlantic Ocean, Stergios D. Zarkogiannis, Shinya Iwasaki, James William Buchanan Rae, Matthew W. Schmidt, P. Graham Mortyn, George Kontakiotis, Jennifer E. Hertzberg, Rosalind E.M. Rickaby Jan 2022

Calcification, Dissolution And Test Properties Of Modern Planktonic Foraminifera From The Central Atlantic Ocean, Stergios D. Zarkogiannis, Shinya Iwasaki, James William Buchanan Rae, Matthew W. Schmidt, P. Graham Mortyn, George Kontakiotis, Jennifer E. Hertzberg, Rosalind E.M. Rickaby

OES Faculty Publications

The mass of well-preserved calcite in planktonic foraminifera shells provides an indication of the calcification potential of the surface ocean. Here we report the shell weight of 8 different abundant planktonic foraminifera species from a set of core-top sediments along the Mid-Atlantic Ridge. The analyses showed that near the equator, foraminifera shells of equivalent size weigh on average 1/3 less than those from the middle latitudes. The carbonate preservation state of the samples was assessed by high resolution X-ray microcomputed tomographic analyses of Globigerinoides ruber and Globorotalia truncatulinoides specimens. The specimen preservation was deemed good and does not overall explain …


Unique Features Of Alarmone Metabolism In Clostridioides Difficile, Asia Poudel, Astha Pokhrel, Adenrele Oludiran, Estevan J. Coronado, Kwincy Alleyne, Marrett M. Gilfus, Raj K. Gurung, Surya B. Adhikari, Erin B. Purcell Jan 2022

Unique Features Of Alarmone Metabolism In Clostridioides Difficile, Asia Poudel, Astha Pokhrel, Adenrele Oludiran, Estevan J. Coronado, Kwincy Alleyne, Marrett M. Gilfus, Raj K. Gurung, Surya B. Adhikari, Erin B. Purcell

Chemistry & Biochemistry Faculty Publications

The “magic spot” alarmones (pp)pGpp, previously implicated in Clostridioides difficile antibiotic survival, are synthesized by the RelA-SpoT homolog (RSH) of C. difficile (RSHCd) and RelQCd. These enzymes are transcriptionally activated by diverse environmental stresses. RSHCd has previously been reported to synthesize ppGpp, but in this study, we found that both clostridial enzymes exclusively synthesize pGpp. While direct synthesis of pGpp from a GMP substrate, and (p)ppGpp hydrolysis into pGpp by NUDIX hydrolases, have previously been reported, there is no precedent for a bacterium synthesizing pGpp exclusively. Hydrolysis of the 5′ phosphate or pyrophosphate from GDP …


Microbial Labilization And Diversification Of Pyrogenic Dissolved Organic Matter, Aleksandar I. Goranov, Andrew S. Wozniak, Kyle W. Bostick, Andrew R. Zimmerman, Siddhartha Mitra, Patrick G. Hatcher Jan 2022

Microbial Labilization And Diversification Of Pyrogenic Dissolved Organic Matter, Aleksandar I. Goranov, Andrew S. Wozniak, Kyle W. Bostick, Andrew R. Zimmerman, Siddhartha Mitra, Patrick G. Hatcher

Chemistry & Biochemistry Faculty Publications

With the increased occurrence of wildfires around the world, interest in the chemistry of pyrogenic organic matter (pyOM) and its fate in the environment has increased. Upon leaching from soils by rain events, significant amounts of dissolved pyOM (pyDOM) enter the aquatic environment and interact with microbial communities that are essential for cycling organic matter within the different biogeochemical cycles. To evaluate the biodegradability of pyDOM, aqueous extracts of laboratory-produced biochars were incubated with soil microbes, and the molecular changes to the composition of pyDOM were probed using ultrahigh-resolution mass spectrometry (Fourier transform–ion cyclotron resonance–mass spectrometry). Given that solar irradiation …


Synthesis Of Oligonucleotides Containing Unnatural Backbone And Regulation Of Crispr Activity Using Inverse Electron Demand Diels-Alder Chemistry, Alyssa Hoy Jan 2022

Synthesis Of Oligonucleotides Containing Unnatural Backbone And Regulation Of Crispr Activity Using Inverse Electron Demand Diels-Alder Chemistry, Alyssa Hoy

Legacy Theses & Dissertations (2009 - 2024)

This thesis describes the synthesis of an oligonucleotide containing an unnatural neutralbackbone. The backbone was constructed using bio-orthogonal inverse electron demand Diels- Alder chemistry between trans-cyclooctene (TCO) and tetrazine (Tz). A TCO phosphoramidite was synthesized and attached to solid support for strand propagation. Uridine monomers containing either bis-TCO or bis-Tz were also synthesized. The oligonucleotide strand was formed by sequential ligation of the bis-Tz and bis-TCO monomers. The oligonucleotide was analyzed using mass spectrometry. This thesis also describes the synthesis of sgRNAs containing non-canonical nucleobases, m1A, m6A, s2U and s4U using the ‘split-and-click’ methodology. The synthetic sgRNAs were assembled using …


The Photo-Transformation Of Free Methionine In The Presence Of Surrogate And Standard Isolate Dissolved Organic Matter Under Sunlit Irradiation, Benjamin J. Mohrhardt Jan 2022

The Photo-Transformation Of Free Methionine In The Presence Of Surrogate And Standard Isolate Dissolved Organic Matter Under Sunlit Irradiation, Benjamin J. Mohrhardt

Dissertations, Master's Theses and Master's Reports

Sulfur (S)-containing amino acids are key sources of carbon, nitrogen, and sulfur involved in protein synthesis, protein function, and providing energy for microbial growth. Dissolved free and combined methionine is one of two S-containing amino acids incorporated into proteins and has been attributed to their stability and function. The oxidation of methionine has received considerable attention given its ubiquitous presence in most biological systems and has been associated with losses in protein function and pathological disorders. In natural waters, methionine is rapidly and selectively taken up by microorganisms to achieve cellular requirements of carbon, nitrogen, and sulfur. The abiotic transformation …


Spatial Geochemical Changes In Central And East Texas Soils Over Time Resulting From Human Decomposition, Isabela Marisol Overturf Jan 2022

Spatial Geochemical Changes In Central And East Texas Soils Over Time Resulting From Human Decomposition, Isabela Marisol Overturf

CMC Senior Theses

Human decomposition is studied to aid forensic investigations and better understand the impact of cemeteries on urban resources like soil and groundwater. The purpose of this study was to identify changes in soil geochemistry at and around a human grave to search for lateral nutrient movement and possibly identify new patterns in elemental concentrations that could be used in estimating post-mortem intervals (PMIs). At the Forensic Anthropology Research Facility (FARF) at Texas State San Marcos, soil samples were collected from a shallow grave over the course of 54 days to conduct analysis for organic matter content, texture, pH, and bulk …


College Of Natural Sciences Newsletter, January 2022, College Of Natural Sciences Jan 2022

College Of Natural Sciences Newsletter, January 2022, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Volume 3, Issue 1

Page 1 Dean's Message
Page 2 Awards & Recognition
Page 3 Outreach in Harrisburg, SD
Page 4 Geography Alumni Named Among 'Highly Cited Researchers', 53rd Annual Geography Convention
Page 5 Geography Convention Speakers, Brookings/SDSU Day
Page 6 Media Coverage of Natural Sciences
Page 7 Open PRAIRIE Data
Page 8 Fall 2021 Dean's List
Page 9 Fall 2021 Dean's List, cont.


Validation Of The Use Of Clathromorphum Compactum Growth And Skeletal Δ18o As A Proxy For Seawater Conditions, Teagan Mcmahon Jan 2022

Validation Of The Use Of Clathromorphum Compactum Growth And Skeletal Δ18o As A Proxy For Seawater Conditions, Teagan Mcmahon

Pitzer Senior Theses

Crustose coralline algae (CCA) are important organisms that create benthic habitat in the photic zone of oceans worldwide. CCAs mechanisms of photosynthesis and calcification may, in some cases, make them vulnerable to climate change and ocean acidification. Therefore, CCA are important not only for their ecological role within ecosystems but also for their ability to indicate the effects that ocean acidification and climate change may have on other marine calcifying organisms. Some species of CCA are known to be useful recorders of paleo oceanic conditions. These climate archives and reconstructions of past environmental conditions are important for understanding past changes …


Investigation Of Dna Hybridization In Localized Systems In Close Proximity, Ashley M. Sewsankar Jan 2022

Investigation Of Dna Hybridization In Localized Systems In Close Proximity, Ashley M. Sewsankar

Honors Undergraduate Theses

Hybridization of two or more DNA or RNA strands is well documented for the process taking place with all strands free in solution or when one strand is immobilized on a substrate. This study contributes to the investigation of the hybridization process when two single DNA strands (ssDNA) are in close proximity. We took advantage of an X sensor in which hybridization of four DNA strands enables the formation of a DNA four-way junction (crossover or X) structure. We immobilized multiple layers of crossover structures to study its hybridization being triggered by short ssDNA coming from solution and further investigate …


Building Tools For Improved Modulation Of The Human Gabaa Receptor, A Central Nervous System Target For The Treatment Of Anxiety, Garrett Edward Zinck Jan 2022

Building Tools For Improved Modulation Of The Human Gabaa Receptor, A Central Nervous System Target For The Treatment Of Anxiety, Garrett Edward Zinck

Theses and Dissertations--Pharmacy

In the U.S., anxiety is recognized as an increasing range of mentally and physically debilitating psychiatric health disorders with significant economic repercussions. Over the last 20 years, several novel anti-anxiety therapies have entered the drug development pipeline, but none have made it to market.

The work in this dissertation focused on structurally modifying valerenic acid (VA), a structurally unique carboxylated sesquiterpene acid found in Valeriana officinalis. VA is putatively reported to have allosteric modulatory activity of the human GABAA receptor, a ligand-gated ion channel responsible for attenuating neurotransmissions. Structural modeling of VA’s GABAA receptor interaction suggests that …


Purification And Activity Assay Optimization Of Bacterial Catalase From Psychrobacter Koprana, Sydney Willis Jan 2022

Purification And Activity Assay Optimization Of Bacterial Catalase From Psychrobacter Koprana, Sydney Willis

Honors Program Theses

To date, catalase protein from bacterial species is not the most widely used commercial catalase. Catalase, the enzyme that breaks down hydrogen peroxide in most living organisms, is an invaluable enzyme in the food, agriculture, and pharmaceutical industries. In 2019, a novel species of a psychrotolerant bacterium was discovered in Cold Harbor, NY. This species, Psychrobacter koprana, exhibits highly active catalase. Preliminary data from activity assays demonstrates that P. koprana catalase has the same activity as commercially available catalase. After purification and activity assay optimization, the activity of this catalase has the potential to be more active than other easily …


Toxic Effects Of Silver Ions On Early Developing Zebrafish Embryos Distinguished From Silver Nanoparticles, Martha S. Johnson, Preeyaporn Songkiatisak, Pavan Kumar Cherukuri, Xiao-Hong Nancy Xu Jan 2022

Toxic Effects Of Silver Ions On Early Developing Zebrafish Embryos Distinguished From Silver Nanoparticles, Martha S. Johnson, Preeyaporn Songkiatisak, Pavan Kumar Cherukuri, Xiao-Hong Nancy Xu

Chemistry & Biochemistry Faculty Publications

Currently, effects of nanomaterials and their ions, such as silver nanoparticles (Ag NPs) and silver ions (Ag+), on living organisms are not yet fully understood. One of the vital questions is whether nanomaterials have distinctive effects on living organisms from any other conventional chemicals (e.g., their ions), owing to their unique physicochemical properties. Due to various experimental protocols, studies of this crucial question have been inconclusive, which hinders rational design of effective regulatory guidelines for safely handling NPs. In this study, we chronically exposed early developing zebrafish embryos (cleavage-stage, 2 hours post-fertilization, hpf) to a dilution series of …