Biochemistry Commons^™

Development, Validation, And Application Of Analytical Methods For Characterizing Adsorbed Protein Orientation, Conformation, And Bioactivity, Aby Thyparambil

All Dissertations

The structure and bioactivity of adsorbed proteins are tightly interrelated and play a key role in their interaction with the surrounding environment. These factors are of critical importance in many biotechnological applications. However, because the bioactive state of an adsorbed protein is a function of the orientation, conformation, and accessibility of its bioactive site(s), the isolated determination of just one or two of these factors will typically not be sufficient to understand the structure-function relationships of the adsorbed layer. Rather a combination of methods is needed to address each of these factors in a synergistic manner to provide a complementary …

Phosphotransacetylase And Xylulose 5-Phosphate/Fructose 6-Phosphate Phosphoketolase: Two Eukaryotic Partners Of Acetate Kinase, Tonya Taylor

All Dissertations

Although acetate is a predominant metabolite produced by many eukaryotic microbes, far less attention has been given to acetate metabolism in eukaryotes than in bacteria and archaea. Acetate kinase (Ack), which catalyzes the reversible phosphorylation of acetate from ATP, is a key enzyme in bacterial acetate metabolism. Ack primarily partners with phosphotransacetylase (Pta), which catalyzes the generation of acetyl phosphate from acetyl-CoA, but can also partner with xylulose 5-phosphate/fructose 6-phosphate phosphoketolase (Xfp), which produces acetyl phosphate from either xylulose 5-phosphate or fructose 6-phosphate. The Ack-Pta pathway, found primarily in bacteria, is also present in lower eukaryotes such as the green …

Synthesis And Characterization Of Carbonized Poly (Divinylbenzene) Microspheres For Carbon/Nanodiamond/Polymer-Based Core-Shell Materials And Applications Of This Mixed-Mode Phase To High-Performance Liquid Chromatography, Chuan-Hsi Hung

Theses and Dissertations

This work focuses on improving the quality of carbon-based core-shell materials for high performance liquid chromatography (HPLC) via the characterization of the core materials, and also the development of chromatographic methods (separations) for them. In the early part of this work, I applied organic synthesis to make uniform, spherical poly(divinylbenzene) (PDVB) microspheres, and then carbonized them to prepare carbon core materials for core-shell particle synthesis. Here, I studied in detail the surface and material properties of these particles with multiple instruments, which allowed me to describe the physical and chemical changes that took place during each treatment. The uniform, spherical …

Recyclable Organocatalysis Of One-Pot Michael/Mannich/Lactamization Sequence For Asymmetric Synthesis Of Fluorinated Poly-Substituted 2-Piperidinones, Anthony P. Tran

Honors College Theses

2-piperidinone (δ-lactam), a bio-interesting nitrogen-containing six-membered ring compound, has attracted much interest from researchers both in synthetic and medicinal chemistry. Polysubstituted piperidine derivatives, such as the δ-lactam, serve as a synthon for numerous biologically relevant structures and pharmaceutical agents. A novel one-pot asymmetric Michael/Mannich/Lactamization sequence promoted by recyclable fluorous bifunctional cinchona alkaloid–thiourea organocatalysts is introduced for the synthesis of polysubstituted 2-piperidinones bearing four contiguous stereocenters, one of which is a fluorinated quaternary chiral center with excellent stereoselectivities (ee up to >99%, dr up to >20:1).

Inducing And Characterizing M2c Macrophages At A Non-Degradable Implant In Vivo, Geoffrey David Keeler

Graduate Theses and Dissertations

The implantation of biomaterials in the body leads to a reaction known as the foreign body response (FBR) which leads to the eventual encapsulation of the biomaterial. This encapsulation proves to be detrimental to certain biomaterials, such as implanted glucose sensors, which rely on interacting with the extracellular space for proper function. Altering the FBR has become of interest in an effort to increase the longevity and integration of biomaterials. One strategy for altering the FBR is by targeting the macrophage, shown to play an important role in the FBR. In this work, the microdialysis sampling technique was used to …

Local Modulation And Measurement Of Macrophage-Derived Bioactive Proteins From Implanted Biomaterials In Rat, Geetika Bajpai

Graduate Theses and Dissertations

Fibrosis around the implanted medical devices is a severe problem that can plague long-term device reliability. Activation of macrophage phenotype (macrophage polarization) has emerged as a new and possible means for reducing fibrosis in the fields of biomaterials and regenerative medicine. Macrophages are phagocytic cells that respond to microenvironmental cues that direct their phenotype. Macrophage activation has been widely studied in mouse and human in the context of tumor biology, yet little information is available regarding how macrophage activation could be used in a biomaterials context. Further, rats rather than mice are the common subjects in biomaterials experiments. A significant …

Beryllium Is A Potent And Unique Gsk-3Β Inhibitor With Potential To Differentially Regulate Glycogen Synthase And Β-Catenin, Ata Ur Rahman Mohammed Abdul

UNLV Theses, Dissertations, Professional Papers, and Capstones

Glycogen Synthase Kinase-3β (GSK-3β) is an important serine/threonine kinase that phosphorylates/regulates diverse and metabolically important proteins. Some of the important substrates of GSK-3β are glycogen synthase, tau, β-catenin, cyclin D1, axin, c-jun, c-myc, Heat Shock Factor–1, BCL-3, CREB, Histone H1.5, mdm2, p21 (CIP1), pyruvate dehydrogenase and many more. De-regulation of GSK-3β has been implicated in diseases like cancer, Alzheimer’s disease, bipolar disorder and type 2 diabetes mellitus. Currently, GSK-3β is one of the most widely studied proteins and there is a great interest in developing potent and efficient GSK-3β-inhibitors for research as well as therapeutic purposes. We demonstrate that beryllium …

Binding Interactions Of (R)- And (S)-Hydroxypropyl-Com Dehydrogenases And The Zinc Knuckle Proteins Air1 And Air2, Jeremy W. Bakelar

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A thorough understanding of protein function requires knowledge of how proteins interact with their substrates and with other proteins. The work entailed in this dissertation describes the binding interactions of proteins from two different model systems: (1) the dehydrogenase enzymes R- and S-HPCDH and (2) the zinc knuckle proteins Air1 and Air2.

R- and S-HPCDH are highly similar enzymes (42% identical) that function in a unique metabolic pathway found in the soil bacterium Xanthobacter autotrophicus. The bacterium produces R- and S-HPCDH simultaneously to facilitate the transformation of two different forms of the organic …

Microbial-Derived Oils And Value-Added Products: Biosynthesis And Applications For Biofuel Production, Alex T. Mccurdy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Efforts are being made to replace petroleum-derived fuels with biofuels in a cost competitive manner. It is apparent that the continued use of petroleum is futile as population and technological growth put increasing pressure on the demand for cheap energy and chemicals. Diminishing resources, civil unrest in the Middle East, and the impact of using petrochemicals on the environment are critical driving forces for research in generating renewable petroleum replacements that can be produced with a limited carbon-footprint. Today, biofuels are derived mostly from land-based plants, but their potential for displacing petroleum is limited due to the competition with available …

Distinguishing Macrophage Activation States By Mass Spectrometry, Matthias Manfred Knust

Graduate Theses and Dissertations

Macrophages are versatile and highly adaptive cells that are involved in a wide range of physiological processes including host defense, homeostasis or regeneration, as well as pathogenesis. They react to their microenvironment, assuming various roles based on chemical and/or physical cues, and can reversibly shift between these so-called activation states. Concurrently, the technique of immunohistochemistry is used to gain spatial information on activated macrophages on tissue sections. The aim of this work was to find mass spectral biomarkers that allow the differentiation of activation states, and establish conditions that can be used in imaging mass spectrometry (IMS) experiments to investigate …

Dna Methylation In Lung Tissues Of Mouse Offspring Exposed In Utero To Polycyclic Aromatic Hydrocarbons, Trevor J. Fish

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Polycyclic aromatic hydrocarbons (PAHs) comprise an important class of environmental pollutants that are known to cause lung cancer in animals and suspected lung carcinogens in humans. PAHs are also known to cause cancer in offspring when provided to a pregnant mouse. Some evidence from cell-based studies points to PAHs as modulators of the epigenome, that is modifications to DNA structure that control the expression of genes. Inappropriate changes to the epigenome and consequently expression of cancer-critical genes are often characteristic of cancer cells. The objective of this thesis research was to determine the impact of transplacental exposure to two model …

Whole Genome Comparison Of A Large Collection Of Mycobacteriophages Reveals A Continuum Of Phage Genetic Diversity, Welkin H. Pope, Charles A. Bowman, Daniel A. Russell, Deborah Jacobs-Sera, David J. Asai, Steven G. Cresawn, William R. Jacobs Jr, Roger W. Hendrix, Jeffrey G. Lawrence, Graham F. Hatfull, Dr. Kathleen Cornely

Chemistry & Biochemistry Faculty Publications

The bacteriophage population is large, dynamic, ancient, and genetically diverse. Limited genomic information shows that phage genomes are mosaic, and the genetic architecture of phage populations remains ill-defined. To understand the population structure of phages infecting a single host strain, we isolated, sequenced, and compared 627 phages of Mycobacterium smegmatis. Their genetic diversity is considerable, and there are 28 distinct genomic types (clusters) with related nucleotide sequences. However, amino acid sequence comparisons show pervasive genomic mosaicism, and quantification of inter-cluster and intra-cluster relatedness reveals a continuum of genetic diversity, albeit with uneven representation of different phages. Furthermore, rarefaction analysis shows …

Repsa-Directed Identification Of Dna-Binding Specificity For Orphan Transcription Factors, Kamir Hiam

Symposium of Student Scholars

The function of many genes and the biological roles of their encoded products are still not well characterized. Given the sequence-specific DNA-binding properties of transcription factor proteins, it is possible to purify them, identify the responsible polypeptide(s), determine their consensus binding sequences, and identify their genomic binding sites. Thus, one can go from cellular extract to proposed biological regulatory roles in relatively short order. Our goal is to identify and characterize orphan DNA-binding proteins in the model organism E. coli K12 using the novel combinatorial technique, REPSA (Restriction Endonuclease Protection Selection Amplification), as well as further develop the REPSA to …

Nmr Spectroscopy Reveals The Presence And Association Of Lipids And Keratin In Adhesive Gecko Setae, Dharamdeep Jain, Alyssa Y. Stark, Peter H. Niewiarowski, Toshikazu Miyoshi, Ali Dhinojwala

Polymer Science Faculty Research

Lipid and protein aggregates are one of the fundamental materials of biological systems. Examples include cell membranes, insect cuticle, vertebrate epidermis, feathers, hair and adhesive structures known as ‘setae’ on gecko toes. Until recently gecko setae were assumed to be composed entirely of keratin, but analysis of footprints left behind by geckos walking on surfaces revealed that setae include various kinds of lipids. However, the arrangement and molecular-level behavior of lipids and keratin in the setae is still not known. In the present study we demonstrate, for the first time, the use of Nuclear Magnetic Resonance (NMR) spectroscopy techniques to …

Urine Proteomics Identifies Preeclampsia Subphenotypes, Michelle R. Axe

Undergraduate Honors Thesis Projects

Preeclampsia is a perinatal complication of unknown etiology, resulting in 76,000 maternal deaths and 500,000 infant deaths annually₁. The Nationwide Children’s Center for Perinatal Research was the first cohort to propose that preeclampsia is rooted in protein misfolding. We aimed to characterize the misfolded protein components of maternal urine samples and to determine if distinct molecular profiles exist for clinical preeclampsia phenotypes. A total of 86 maternal urine samples from Yale-New Haven Hospital were analyzed for this study, from six clinical preeclampsia subphenotypes- pregnant control (n=10), idiopathic proteinuria (n=15), mild preeclampsia (n=14), superimposed preeclampsia (n=12), typical severe preeclampsia …

The Effect Of Red Maple Leaf Toxicosis On Reduced Glutathione Levels In Equine Erythrocytes In Vitro, Madeline A. Rohl

Undergraduate Honors Thesis Projects

Red maple leaf toxicosis is an equine blood disorder resulting from the consumption of wilted red maple (Acer rubrum L.) leaves by horses. Compounds within the leaves of red maple have oxidative effects on equine erythrocytes and can cause hemolysis of erythrocytes, the conversion of hemoglobin to methemoglobin, and the production of Heinz bodies. Reduced glutathione is important in the protection of equine erythrocytes from these oxidative events; however, in the presence of red maple toxin, glutathione is rapidly oxidized and is unavailable. The objective of this study is to determine whether the presence of vitamin C alters levels …

Investigating The Initial Detection Stage Of Meiotic Silencing By Unpaired Dna In The Model Organism Neurospora Crassa, Pegan A. Sauls

Theses and Dissertations

In an attempt to neutralize transposable elements or retrovirus invasions Neurospora crassa will rely on one of its many genome defense mechanism, Meiotic Silencing by Unpaired DNA (MSUD). MSUD works in a two-step process that first detects unpaired sequences between homologous chromosomes followed by downstream silenced expression of the sequence. The ultimate silencing stage of MSUD is widely accepted to operate through an RNAi-like system. However, the mechanics of the detection step of MSUD remains elusive. The research presented attempts to elaborate on how the initial stage of MSUD occurs and its specifics. First, a genetic approach is utilized to …

Methods In Extracting Dna: Using Phenol-Chloroform On Formalin Fixed Human Brain Tissue, Stefanie Rigg, Nathaniel Kennedy

Undergraduate Research Conference

Genetic markers of diseases can be studied post-mortem with the isolation of DNA from tissues. While protocols exist for DNA extraction from fresh and formalin-fixed-paraffin embedded tissue and formalin fixed hard tissues such as bone, there are no published methods for formalin fixed soft tissue such as brain. Extractions from formalin fixed soft tissues are more difficult due to the higher amount of cellular degradation that results from fixation. The development of efficient DNA extraction protocols for formalin fixed soft tissues will allow post-mortem study of genetic markers and aid in identification of genetic diseases. Existing techniques of phenol-chloroform extraction …

Reagent Pencils: A New Technique For Solvent-Free Deposition Of Reagents Onto Paper-Based Microfluidic Devices, Haydn T. Mitchell, Isabelle C. Noxon, Cory A. Chaplan, Samantha J. Carlton, Cheyenne H. Liu, Kirsten A. Ganaja, Nathaniel W. Martinez, Chad Immoos, Philip Costanzo, Andres W. Martinez

Chemistry and Biochemistry

Custom-made pencils containing reagents dispersed in a solid matrix were developed to enable rapid and solvent-free deposition of reagents onto membrane-based fluidic devices. The technique is as simple as drawing with the reagent pencils on a device. When aqueous samples are added to the device, the reagents dissolve from the pencil matrix and become available to react with analytes in the sample. Colorimetric glucose assays conducted on devices prepared using reagent pencils had comparable accuracy and precision to assays conducted on conventional devices prepared with reagents deposited from solution. Most importantly, sensitive reagents, such as enzymes, are stable in the …

An Active Site Loop Mutant Of A Zinc Metallo-Deubiquitinase Suggests The Importance Of Loop Dynamics To Catalysis, Amy N. Bueno

Open Access Theses

AMSH is a conserved zinc metalloprotease that functions with endosomal sorting complexes required for transport (ESCRT) machinery in order to down regulate and degrade cell-surface receptors. It has been shown to have high specificity toward Lys63-linked polyubiquitin chains, a signal used for receptor down regulation by ESCRT machinery. It has previously been found that Sst2, an AMSH orthologue from fission yeast, contains a flexible "loop" near the proximal ubiquitin binding site, composed of residues L402 and F403. The different mobility of the side chains of these residues contribute to the opening and closing conformation of the catalytic cleft which allow …

Support Needs Of Young Ovarian Cancer Survivors: A Pilot Study, Aurelie Chuong

Open Access Theses

Purpose. Young ovarian cancer survivor (18 years old or older but diagnosed before the age of 34 years old) support needs (i.e., physical and daily living, psychological, sexual, patient care and support, health system and information) were examined to guide the design and implementation of future young adult and adolescent cancer support groups and interventions. Method. This cross-sectional pilot study included 11 young ovarian cancer survivors. The Supportive Care Needs Survey Short Form 34 (SCNS-SF34) was used and open-ended questions were added. Results. The calculated standardized scores for the SCNS-SF34 survey results showed that sexuality needs were ranked highest (41.7 …

Developmentally Regulated Sumoylation In The Ciliate Tetrahymena Thermophila, Amjad M. Nasir

Open Access Dissertations

The Small Ubiquitin-like MOdifier (SUMO) protein regulates numerous nuclear events such as transcription, mitosis and meiosis and DNA repair. These processes are critical to the programmed nuclear events of conjugation in ciliates and provide the potential to investigate developmentally regulated SUMOylation. We predicted a developmental increase in SUMOylation during late conjugation based on the extensive genome remodeling in the developing macronucleus (anlagen) ofTetrahymena thermophila. Immunoblotting of cell lysates from vegetative and mating cells using anti-SUMO antibodies revealed distinct developmental differences and an increased signal correlated with formation of the anlagen. Immunofluorescence of mating Tetrahymena cells with the same antibody …

“Analyze, Acquire, Apply, And Write” As A New Learning Model In Science, Jeong Choe

Faculty Publications & Research

I have developed a new teaching and learning model called AAAW, which stand for Analyze, Acquire, Apply and Write. This model grows from action research and unique experience in teaching a biochemistry course to high school students who are talented in math and science. In this model, students first "Analyze" lab data to generate questions that lead them to "Acquire" background knowledge. Students then go back to the data and "Apply" their new knowledge to better understand the data. Finally, students "Write" about the connections they make from their reading, data analysis, and application of the data. The rationale behind …

Structural Analysis Of The 14-3-3Ζ/Chibby Interaction Involved In Wnt/Β-Catenin Signaling, Ryan C Killoran, Jingsong Fan, Daiwen Yang, Brian H Shilton, Wing-Yiu Choy

Biochemistry Publications

The partially disordered Chibby (Cby) is a conserved nuclear protein that antagonizes the Wnt/β-catenin signaling pathway. By competing with the Tcf/Lef family proteins for binding to β-catenin, Cby abrogates the β-catenin-mediated transcription of Wnt signaling genes. Additionally, upon phosphorylation on S20 by the kinase Akt, Cby forms a complex with 14-3-3 to facilitate the nuclear export of β-catenin, which represents another crucial mechanism for the regulation of Wnt signaling. To obtain a mechanistic understanding of the 14-3-3/Cby interaction, we have extensively characterized the complex using X-ray crystallography, nuclear magnetic resonance (NMR) spectroscopy, and isothermal titration calorimetry (ITC). The crystal structure …

Molecular Effects Of Cancer-Associated Somatic Mutations On The Structural And Target Recognition Properties Of Keap1., Halema Khan, Ryan C Killoran, Anne Brickenden, Jingsong Fan, Daiwen Yang, Wing-Yiu Choy

Biochemistry Publications

Kelch-like ECH-associated protein 1 (Keap1) plays an important regulatory role in the nuclear factor erythroid 2-related factor 2 (Nrf2)-dependent oxidative stress response pathway. It functions as a repressor of Nrf2, a key transcription factor that initiates the expression of cytoprotective enzymes during oxidative stress to protect cells from damage caused by reactive oxygen species. Recent studies show that mutations of Keap1 can lead to aberrant activation of the antioxidant pathway, which is associated with different types of cancers. To gain a mechanistic understanding of the links between Keap1 mutations and cancer pathogenesis, we have investigated the molecular effects of a …

Functional Screening Of The Cronobacter Sakazakii Baa-894 Genome Reveals A Role For Prop (Esa_02131) In Carnitine Uptake, Audrey Feeney, Roy D. Sleator

Department of Biological Sciences Publications

Cronobacter sakazakii is a neonatal pathogen responsible for up to 80% of fatalities in infected infants. Low birth weight infants and neonates infected with C. sakazakii suffer necrotizing enterocolitis, bacteraemia and meningitis. The mode of transmission most often associated with infection is powdered infant formula (PIF) which, with an aw of ∼0.2, is too low to allow most microorganisms to persist. Survival of C. sakazakii in environments subject to extreme hyperosmotic stress has previously been attributed to the uptake of compatible solutes including proline and betaine. Herein, we report the construction and screening of a C. sakazakii genome bank and …

Role Of Syk In The Regulation Of Cytoskeleton And Stress Granules In Breast Cancer, Mariya Krisenko

Open Access Dissertations

The Syk protein-tyrosine kinase, a well-characterized modulator of immune recognition receptor signaling, also plays important, but poorly characterized, roles in tumor progression, acting as an inhibitor of cellular motility and metastasis in highly invasive cancer cells. Multiharmonic atomic force microscopy (AFM) was used to map nanomechanical properties of live MDA-MB-231 breast cancer cells either lacking or expressing Syk. The expression of Syk dramatically altered the cellular topography, reduced cell height, increased elasticity, increased viscosity, and allowed visualization of a more substantial microtubule network. The microtubules of Syk-expressing cells were more stable to nocodazole-induced depolymerization and were more highly acetylated than …

Structural And Biophysical Analysis Of The Proteasomal Deubiquitinase, Uch37, Marie Elizabeth Morrow

Open Access Dissertations

Ubiquitin carboxyl-terminal hydrolase 37, or UCH37, is a deubiquitinating enzyme associated with the 26S proteasome, the primary protein degradation machinery in eukaryotic cells. UCH37 is responsible for the disassembly of polymeric ubiquitin chains, or polyubiquitin, which have been ligated onto proteins in order to target them for degradation. The 26S utilizes two associated deubiquitinating enzymes, UCH37 and USP14, and one intrinsic, Rpn11, to remove polyubiquitin chains from substrate proteins as they are unfolded and translocated into the proteolytic core of the proteasome, where proteins are cleaved into small peptides and then released for recycling by the cell. UCH37 associates with …

Paralogous Genes In Arabidopsis Thaliana Contribute To Diversified Phenylpropanoid Metabolism, Li Yi

Open Access Dissertations

Significant evidence supports the idea that gene duplication drives the evolution of new gene function. Besides being silenced, duplicated genes can either neofunctionalize or subfunctionalize under selective pressure or neutral drift. Understanding the trajectory of how each gene is fixed and presumably provides added fitness remains difficult. Plant specialized metabolism provides an attractive platform to study the fixation of genes post duplication and how this process leads to the chemical diversity seen today. Specialized metabolites by definition are thought to be dispensable under normal growth conditions. Thus deleterious mutations occurring in paralogous genes that otherwise would be selected against in …

Biochemical Investigation Of The Ubiquitin Carboxyl-Terminal Hydrolase Family, Joseph Rashon Chaney

Open Access Dissertations

The proteasome is the machinery in eukaryotic cells that degrades protein and recycles the amino acids. Protein degradation is a highly regulated process which starts by the attachment of chains of ubiquitin, which serves as a tag that marks a protein for degradation. This function involves the work of several proteins at the proteasome that work either as ubiquitin chaperones, ubiquitin binders or cleave ubiquitin from the protein that is to be degraded. As this is a highly regulated process, various irregularities can have deleterious effects including the onset of disease, including cardiovascular, cancer, and neurological. ^ The focus of …