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Full-Text Articles in Biochemistry, Biophysics, and Structural Biology

Resurrecting The Regulatory Properties Of The Ostreococcus Tauri Adp-Glucose Pyrophosphorylase Large Subunit, Carlos M. Figueroa, Misty L. Kuhn, Benjamin L. Hill, Alberto A. Iglesias, Miguel A. Ballicora Oct 2018

Resurrecting The Regulatory Properties Of The Ostreococcus Tauri Adp-Glucose Pyrophosphorylase Large Subunit, Carlos M. Figueroa, Misty L. Kuhn, Benjamin L. Hill, Alberto A. Iglesias, Miguel A. Ballicora

Chemistry: Faculty Publications and Other Works

ADP-glucose pyrophosphorylase (ADP-Glc PPase) catalyzes the first committed step for the synthesis of glycogen in cyanobacteria and starch in green algae and plants. The enzyme from cyanobacteria is homotetrameric (α4), while that from green algae and plants is heterotetrameric (α2β2). These ADP-Glc PPases are allosterically regulated by 3-phosphoglycerate (3PGA, activator) and inorganic orthophosphate (Pi, inhibitor). Previous studies on the cyanobacterial and plant enzymes showed that 3PGA binds to two highly conserved Lys residues located in the C-terminal domain. We observed that both Lys residues are present in the small (α) subunit of the Ostreococcus tauri enzyme; however, one of these ...


Starch Synthesis In Ostreococcus Tauri: The Starch-Binding Domains Of Starch Synthase Iii-B Are Essential For Catalytic Activity, Julieta Barchiesi, Maria Belen Velazquez, Nicolas Palopoli, Alberto A. Iglesias, Diego F. Gomez-Casati, Miguel A. Ballicora, Maria Victoria Busi Oct 2018

Starch Synthesis In Ostreococcus Tauri: The Starch-Binding Domains Of Starch Synthase Iii-B Are Essential For Catalytic Activity, Julieta Barchiesi, Maria Belen Velazquez, Nicolas Palopoli, Alberto A. Iglesias, Diego F. Gomez-Casati, Miguel A. Ballicora, Maria Victoria Busi

Chemistry: Faculty Publications and Other Works

Starch is the major energy storage carbohydrate in photosynthetic eukaryotes. Several enzymes are involved in building highly organized semi-crystalline starch granules, including starch-synthase III (SSIII), which is widely conserved in photosynthetic organisms. This enzyme catalyzes the extension of the α-1,4 glucan chain and plays a regulatory role in the synthesis of starch. Interestingly, unlike most plants, the unicellular green alga Ostreococcus tauri has three SSIII isoforms. In the present study, we describe the structure and function of OsttaSSIII-B, which has a similar modular organization to SSIII in higher plants, comprising three putative starch-binding domains (SBDs) at the N-terminal region ...


On The Roles Of Wheat Endosperm Adp-Glucose Pyrophosphorylase Subunits, Danisa M. L. Ferrero, Matias D. Asencion Diez, Misty L. Kuhn, Christine A. Falaschetti, Claudia V. Piattoni, Alberto A. Iglesias, Miguel A. Ballicora Oct 2018

On The Roles Of Wheat Endosperm Adp-Glucose Pyrophosphorylase Subunits, Danisa M. L. Ferrero, Matias D. Asencion Diez, Misty L. Kuhn, Christine A. Falaschetti, Claudia V. Piattoni, Alberto A. Iglesias, Miguel A. Ballicora

Chemistry: Faculty Publications and Other Works

The ADP-glucose pyrophosphorylase from wheat endosperm controls starch synthesis in seeds and has unique regulatory properties compared to others from this family. It comprises two types of subunits, but despite its importance little is known about their roles. Here, we synthesized de novo the wheat endosperm ADP-glucose pyrophosphorylase small (S) and large (L) subunit genes, heterologously expressed them in Escherichia coli, and kinetically characterized the recombinant proteins. To understand their distinct roles, we co-expressed them with well characterized subunits from the potato tuber enzyme to obtain hybrids with one S subunit from one source and an L subunit from the ...


Folding Of Gα Subunits: Implications For Disease States, Matthew Najor, Brian D. Leverson, Jesse L. Goossens, Saad Kothawala, Kenneth W. Olsen, Duarte Mota De Freitas Oct 2018

Folding Of Gα Subunits: Implications For Disease States, Matthew Najor, Brian D. Leverson, Jesse L. Goossens, Saad Kothawala, Kenneth W. Olsen, Duarte Mota De Freitas

Chemistry: Faculty Publications and Other Works

G-proteins play a central role in signal transduction by fluctuating between “on” and “off” phases that are determined by a conformational change. cAMP is a secondary messenger whose formation is inhibited or stimulated by activated Giα1 or Gsα subunit. We used tryptophan fluorescence, UV/vis spectrophotometry, and circular dichroism to probe distinct structural features within active and inactive conformations from wild-type and tryptophan mutants of Giα1 and Gsα. For all proteins studied, we found that the active conformations were more stable than the inactive conformations, and upon refolding from higher temperatures, activated wild-type subunits recovered significantly more native structure. We ...


A Series Of 4- And 5-Coordinate Ni(Ii) Complexes: Synthesis, Characterization, Spectroscopic, And Dft Studies, Jack Ghannam, Talal Al Assil, Trey C. Pankratz, Richard L. Lord, Matthias Zeller, Wei-Tsung Lee Jul 2018

A Series Of 4- And 5-Coordinate Ni(Ii) Complexes: Synthesis, Characterization, Spectroscopic, And Dft Studies, Jack Ghannam, Talal Al Assil, Trey C. Pankratz, Richard L. Lord, Matthias Zeller, Wei-Tsung Lee

Chemistry: Faculty Publications and Other Works

A series of four- and five-coordinate Ni(II) complexes CztBu(PyriPr)2NiX (13 and 1·THF–3·THF), where X = Cl, Br, and I, were synthesized and fully characterized by NMR and UV–vis spectroscopy, X-ray crystallography, cyclic voltammetry, and density functional theory calculations. The solid-state structures of 13 reveal rare examples of seesaw Ni(II) complexes. In solution, 13 bind reversibly to a THF molecule to form five-coordinate adducts. The electronic transitions in the visible region (630–680 nm), attributed to LMCT bands, for 13 exhibit a bathochromic shift. The ...


Practical Spectrophotometric Assay For The Dape-Encoded N-Succinyl-L,L-Diaminopimelic Acid Desuccinylase, A Potential Antibiotic Target, Tahira K. Heath, Marlon R. Lutz Jr., Cory T. Reidl, Estefany R. Guzman, Claire A. Herbert, Boguslaw P. Nocek, Richard C. Hotz, Kenneth W. Olsen, Miguel A. Ballicora, Daniel P. Becker Apr 2018

Practical Spectrophotometric Assay For The Dape-Encoded N-Succinyl-L,L-Diaminopimelic Acid Desuccinylase, A Potential Antibiotic Target, Tahira K. Heath, Marlon R. Lutz Jr., Cory T. Reidl, Estefany R. Guzman, Claire A. Herbert, Boguslaw P. Nocek, Richard C. Hotz, Kenneth W. Olsen, Miguel A. Ballicora, Daniel P. Becker

Chemistry: Faculty Publications and Other Works

A new enzymatic assay for the bacterial enzyme succinyl-diaminopimelate desuccinylase (DapE, E.C. 3.5.1.18) is described. This assay employs N6-methyl-N2-succinyl-L,L-diaminopimelic acid (N6-methyl-L,L-SDAP) as the substrate with ninhydrin used to detect cleavage of the amide bond of the modified substrate, wherein N6-methylation enables selective detection of the primary amine enzymatic product. Molecular modeling supported preparation of the mono-N6-methylated-L,L-SDAP as an alternate substrate for the assay, given binding in the active site of DapE predicted to be comparable to the endogenous substrate. The alternate ...


Characterizing The Requirement Of The Cmi/Trr Compass-Like Complex During Drosophila Development, Timothy Nickels Jan 2018

Characterizing The Requirement Of The Cmi/Trr Compass-Like Complex During Drosophila Development, Timothy Nickels

Master's Theses

The MLR family of COMPASS-like complexes are histone methyltransferase complexes that are associated with the activation of gene enhancers. In D. melanogaster, Cara mitad (Cmi, also known as Lpt) and Trithorax related (Trr) are central subunits of a complex orthologous to mammalian Lysine methyltransferase 2 C and D (KMT2C and KMT2D, also known as MLL3 and MLL2/4) that catalyze H3K4 monomethylation. Previous studies have demonstrated that mutations in these genes are associated with cancer and developmental disorders, but the mechanisms by which these alterations contribute to disease states are unknown. The Cmi-containing COMPASS-like complex and orthologous vertebrate complexes have ...


Comparison Between The Structure-Function Relationship In The Wild Type Gαi1 Protein And Its Oncogenic Mutant, Jesse Lee Goossens Jan 2018

Comparison Between The Structure-Function Relationship In The Wild Type Gαi1 Protein And Its Oncogenic Mutant, Jesse Lee Goossens

Dissertations

Many signal transduction pathways are regulated by guanine nucleotide-binding (G?) proteins, which function as molecular switches fluctuating between active and inactive conformations. Proper function depends on three flexible switch regions that are involved in the relatively slow hydrolysis of GTP. Deep sequencing studies have found mutations in the GNAS and GNAI1 genes involved in tumorigenesis, among which include a mutation corresponding to a highly conserved arginine residue in the switch II region. A mutation in GNAI1 encoding an R208Q change in G?i1 has been linked to intestinal cancers. We investigated the molecular basis of oncogenesis of this mutant by ...


A Discrete Loop In Serca N-Domain Plays A Role In Serca Headpiece Dynamics And Function, Olga N. Raguimova Jan 2018

A Discrete Loop In Serca N-Domain Plays A Role In Serca Headpiece Dynamics And Function, Olga N. Raguimova

Dissertations

The sarco/endoplasmic reticulum calcium ATPase (SERCA) is the major regulator of Ca2+ levels in the cell. Deficient calcium handling in the heart has been linked to heart failure, a leading cause of death in developed countries. As of today, targeting SERCA to enhance cardiac function has not been successful due to lack of details about SERCA structural dynamics during Ca2+ transport.

In my research, I utilized MD simulations and variety of physical assays to determine the role of Nβ5-β6 loop in regulation of SERCA structural dynamics during Ca2+ transport. Previous MD simulations by our lab predicted that the Nβ5-β6 ...


Inhibition Of Mutant Egfr In Nsclc Promotes Endothelin-1-Mediated Nsclc Disease Progression, Stephen Ollosi Jan 2018

Inhibition Of Mutant Egfr In Nsclc Promotes Endothelin-1-Mediated Nsclc Disease Progression, Stephen Ollosi

Master's Theses

Angiogenesis in NSCLC has been identified as important therapeutic target in combination with EGFR TKIs. However, only small incremental advancements have been made for the use of angiogenesis inhibitors in NSCLC and it remains elusive why the inhibition of VEGF-mediated neovascularization is not therapeutically efficacious. I present experimental evidence that a subpopulation of NSCLC cells with EGFR TKI-induced EMT contributes toward the attenuation of the response to EGFR TKI therapy. One of the hallmarks of cancer is heterogeneity and I have previously demonstrated that tumor heterogeneity within NSCLC cells lines harboring EGFR kinase domain mutations gives rise to divergent resistance ...


Structural Evidence Of A Major Conformational Change Triggered By Substrate Binding In Dape Enzymes: Impact On The Catalytic Mechanism, Boguslaw Nocek, Cory Reid, Anna Starus, Tahirah Heath, David Bienvenues, Jerzy Osipiuk, Robert Jedrzeczak, Andrzej Joachimiak, Daniel P. Becker Ph.D., Richard C. Holz Dec 2017

Structural Evidence Of A Major Conformational Change Triggered By Substrate Binding In Dape Enzymes: Impact On The Catalytic Mechanism, Boguslaw Nocek, Cory Reid, Anna Starus, Tahirah Heath, David Bienvenues, Jerzy Osipiuk, Robert Jedrzeczak, Andrzej Joachimiak, Daniel P. Becker Ph.D., Richard C. Holz

Chemistry: Faculty Publications and Other Works

The X-ray crystal structure of the dapE-encoded N-succinyl-l,l-diaminopimelic acid desuccinylase from Haemophilus influenzae (HiDapE) bound by the products of hydrolysis, succinic acid and l,l-DAP, was determined at 1.95 Å. Surprisingly, the structure bound to the products revealed that HiDapE undergoes a significant conformational change in which the catalytic domain rotates ∼50° and shifts ∼10.1 Å (as measured at the position of the Zn atoms) relative to the dimerization domain. This heretofore unobserved closed conformation revealed significant movements within the catalytic domain compared to that of wild-type HiDapE, which results in effectively closing ...


Kinematic Difference Between A Biological Cell And An Artificial Vesicle In A Strong Dc Electric Field – A “Shell” Membrane Model Study, Hui Ye Aug 2017

Kinematic Difference Between A Biological Cell And An Artificial Vesicle In A Strong Dc Electric Field – A “Shell” Membrane Model Study, Hui Ye

Biology: Faculty Publications and Other Works

Background

Cellular biomechanics can be manipulated by strong electric fields, manifested by the field-induced membrane deformation and migration (galvanotaxis), which significantly impacts normal cellular physiology. Artificial giant vesicles that mimic the phospholipid bilayer of the cell membrane have been used to investigate the membrane biomechanics subjected to electric fields. Under a strong direct current (DC) electric field, the vesicle membrane demonstrates various patterns of deformation, which depends on the conductivity ratio between the medium and the cytoplasm. The vesicle exhibits prolate elongation along the direction of the electric field if the cytoplasm is more conductive than the medium. Conversely, the ...


Generating Enzyme And Radical‐Mediated Bisubstrates As Tools For Investigating Gcn5‐Related N‐Acetyltransferases, Cory T. Reidl, Karolina A. Majorek, Joseph Dang, David Tran, Kristen Jew, Melissa Law, Yasmine Payne, Wladek Minor, Daniel P. Becker, Misty L. Kuhn Jul 2017

Generating Enzyme And Radical‐Mediated Bisubstrates As Tools For Investigating Gcn5‐Related N‐Acetyltransferases, Cory T. Reidl, Karolina A. Majorek, Joseph Dang, David Tran, Kristen Jew, Melissa Law, Yasmine Payne, Wladek Minor, Daniel P. Becker, Misty L. Kuhn

Chemistry: Faculty Publications and Other Works

Gcn5‐related N‐acetyltransferases (GNATs) are found in all kingdoms of life and catalyze important acyl transfer reactions in diverse cellular processes. While many 3D structures of GNATs have been determined, most do not contain acceptor substrates in their active sites. To expand upon existing crystallographic strategies for improving acceptor‐bound GNAT structures, we synthesized peptide substrate analogs and reacted them with CoA in PA4794 protein crystals. We found two separate mechanisms for bisubstrate formation: (a) a novel X‐ray induced radical‐mediated alkylation of CoA with an alkene peptide and (b) direct alkylation of CoA with a halogenated peptide ...


Plp And Gaba Trigger Gabr-Mediated Transcription Regulation In Bacillus Subtilis Via External Aldimine Formation, Rui Wu, Ruslan Sanishvili, Boris R. Belitsky, Jose I. Juncosa, Hoang V. Le, Helaina J. S. Lehrer, Michael Farley, Richard B. Silverman, Gregory A. Petsko, Dagmar Ringe, Dali Liu Mar 2017

Plp And Gaba Trigger Gabr-Mediated Transcription Regulation In Bacillus Subtilis Via External Aldimine Formation, Rui Wu, Ruslan Sanishvili, Boris R. Belitsky, Jose I. Juncosa, Hoang V. Le, Helaina J. S. Lehrer, Michael Farley, Richard B. Silverman, Gregory A. Petsko, Dagmar Ringe, Dali Liu

Chemistry: Faculty Publications and Other Works

The Bacillus subtilis protein regulator of the gabTD operon and its own gene (GabR) is a transcriptional activator that regulates transcription of γ-aminobutyric acid aminotransferase (GABA-AT; GabT) upon interactions with pyridoxal-5′-phosphate (PLP) and GABA, and thereby promotes the biosynthesis of glutamate from GABA. We show here that the external aldimine formed between PLP and GABA is apparently responsible for triggering the GabR-mediated transcription activation. Details of the “active site” in the structure of the GabR effector-binding/oligomerization (Eb/O) domain suggest that binding a monocarboxylic γ-amino acid such as GABA should be preferred over dicarboxylic acid ligands. A reactive ...


Potential Efficacy Of Targeting Mll1 In Breast Cancer, Austin Gable Holmes Jan 2017

Potential Efficacy Of Targeting Mll1 In Breast Cancer, Austin Gable Holmes

Master's Theses

In 2017, it is estimated that breast cancer will be the most prevalent newly diagnosed cancer in females, at 30% in the U.S. alone1. From the early 1990s to 2014 the death rate in females from breast cancer has dropped by 10% but still stands as the second highest cancer related death in females in the U.S.2. One of the biggest hurdles in breast cancer research is disease heterogeneity. New mechanisms of disease development and progression are encountered frequently. One mechanism studied in the past decades is epigenetics. It has been theorized that the cancer epigenome can ...


Utilizing Single-Molecule Fret Methods To Study Conformational Changes In Trim5Α, Margret Suzanne Bradley Jan 2017

Utilizing Single-Molecule Fret Methods To Study Conformational Changes In Trim5Α, Margret Suzanne Bradley

Master's Theses

Single-molecule FRET (smFRET) is a method by which dynamic conformational changes can be monitored in a protein microscopically and in real time. smFRET relies on the creation of FRET (Förster Resonance Energy Transfer) between small molecule fluorophores conjugated to the biomolecules of interest. FRET efficiency allows calculation of interfluorophore distances. Changes in FRET efficiency represent changes in protein conformation which can inform further structural and molecular studies of the protein of interest. For example, in the Campbell Lab, we study the protein TRIM5α, an antiretroviral cellular protein which can cause premature dissociation of the HIV capsid core by an ...


Frnk Regulatory Complex Formation With Fak Is Regulated By Erk Mediated Serine 217 Phosphorylation, Taylor J. Zak Jan 2017

Frnk Regulatory Complex Formation With Fak Is Regulated By Erk Mediated Serine 217 Phosphorylation, Taylor J. Zak

Dissertations

Focal adhesion kinase related non-kinase (FRNK) is an endogenous inhibitor of focal adhesion kinase (FAK) that has traditionally been used to inhibit FAK signaling in a variety of experiments and is also an important endogenous regulator of FAK signaling. More recently, FRNK has been shown to be of increasing importance in some pathologic conditions. Despite the increasing importance of FRNK, the molecular mechanism by which it functions remains unclear. In addition, FRNK contains several phosphorylation sites with unknown importance and function. Here I hypothesize that FRNK can inhibit FAK by binding directly to FAK within focal adhesions. Furthermore, I propose ...


The Role Of C-Abl Kinase In Hcc Development, Lennox Chitsike Jan 2016

The Role Of C-Abl Kinase In Hcc Development, Lennox Chitsike

Master's Theses

Hepatocellular Carcinoma is the second most lethal cancer after pancreatic cancer. Unresectable HCC tumors carry a poor prognosis and few treatment options are available. The dismal prognosis is mainly due to limited therapy options and molecularly targeted therapy is deemed as solution. Here, we report a novel role of c-Abl in HCC development. We provide evidence of c-Abl activation in human HCC samples compared to normal liver. Using genetic and pharmacological tools, we show that c-Abl plays a vital role in HCC progression in vitro and in vivo. We have identified Axl as an effector in processes mediated by c-Abl ...


Mechanistic Variations Of The Bronsted Linear Free Energy Relationships For Nonezymatic Nucleotidyl Transfer Reactions, Zheng Zhang Jan 2016

Mechanistic Variations Of The Bronsted Linear Free Energy Relationships For Nonezymatic Nucleotidyl Transfer Reactions, Zheng Zhang

Dissertations

As the essential enzymes in human bodies, DNA polymerases play a significant role in DNA replication, repair, genetic recombination, and reverse transcription. In 1956, the enzyme of DNA polymerase I, also named as Pol I, was discovered by Arthur Kornberg and colleagues. Subsequently, the Noble Committee had decided that the Noble Prize in Physiology or Medicine for 1959 was to be awarded to Kornberg for his excellent original work that describes the DNA replication process whereby the DNA polymerase copies the nucleotide sequence of a DNA template strand. Because of the complex enzyme structure in the DNA polymerase, it is ...


A Bioluminescence Sensor Of Nlrp3 Inflammasome Activation, Michael Alexander Winek Jan 2016

A Bioluminescence Sensor Of Nlrp3 Inflammasome Activation, Michael Alexander Winek

Master's Theses

The innate immune system is many organisms first line of defense against pathogenic insult or tissue damage. This defense strategy is intent on restoring homeostasis upon perturbation. Upon activation of the innate immune system in humans, an oligomeric protein complex termed the “Inflammasome” forms in myeloid cells. The canonical output of activation of any subset of inflammasome is Caspase-1-mediated secretion of pro-inflammatory cytokines IL1β and IL18. Chronic or uncontrolled inflammasome activation is at the core of myriad economically burdening diseases. In many of these diseases, endogenous factors chronically engage the innate immune system. To study these diseases in in vivo ...


Heart And Sole: The Functional Role Of Fast-Skeletal Myosin Binding Protein-C In Cardiac And Skeletal Muscle, Brian Leei Lin Jan 2016

Heart And Sole: The Functional Role Of Fast-Skeletal Myosin Binding Protein-C In Cardiac And Skeletal Muscle, Brian Leei Lin

Dissertations

The goal of my dissertation was to compare and contrast the function of all three major isoforms of Myosin Binding Protein-C (MyBP-C): slow-skeletal, fast-skeletal, and cardiac (ssMyBP-C, fsMyBP-C, and cMyBP-C, respectively), with a focus on the least characterized isoform, fsMyBP-C. Using a variety of ex vivo, in vitro, and in silico methods, my research demonstrated that the N-terminal region of all MyBP-C isoforms bind to actin and shift tropomyosin, thus activating the thin filament during contraction. Furthermore, each isoform differentially activated the thin filament over isoform-specific ranges of Ca2+: slow-skeletal activates at low Ca2+, fast-skeletal activates at higher Ca2+, and ...


Studies Into The Allosteric Regulation Of Adp-Glucose Pyrophosphorylases, Benjamin Luke Hill Jan 2016

Studies Into The Allosteric Regulation Of Adp-Glucose Pyrophosphorylases, Benjamin Luke Hill

Dissertations

The synthesis of glycogen in bacteria and starch in plants is allosterically controlled by the production of ADP-glucose by ADP-glucose pyrophosphorylase. Using computational studies, site directed mutagenesis, and kinetic characterization, and protein crystallography we found a critical region for transmitting the allosteric signal in the Escherichia coli and A. tumefaciens ADP-glucose pyrophosphorylase. Molecular dynamics simulations and structural comparisons with other ADP-glucose pyrophosphorylases provided information to hypothesize communication pathways that link allosteric and active sites, and this was tested by site-directed mutagenesis and kinetic characterization of the mutant enzymes. In addition, the application of x-ray crystallography enabled the pinpointing of the ...


The Role Of Foxo Transcription Factors In Alcohol-Induced Deficient Fracture Repair, Philip M. Roper Jan 2016

The Role Of Foxo Transcription Factors In Alcohol-Induced Deficient Fracture Repair, Philip M. Roper

Dissertations

Proper and complete repair of a bone fracture is essential in quality of life maintenance, but poor healing and fracture malunion are still medically and socially relevant problems. Alcohol abuse impairs normal fracture healing, leading to delayed or incomplete union. This dissertation aims to clarify mechanisms behind this alcohol-induced impaired healing, thereby elucidating potential methods of intervention.

Alcohol-induced oxidative stress has been linked to many morbidities associated with alcohol abuse. This dissertation elucidates a potential mechanism through which alcohol inhibits fracture healing by increasing oxidative stress. Using a rodent model, I found that alcohol exposure decreases fracture callus formation and ...


The Role Of Microrna In Cardioprotection: Ischemic Preconditioning And Mesenchymal Stem Cell Paracrine Effects, Kristin Luther Jan 2016

The Role Of Microrna In Cardioprotection: Ischemic Preconditioning And Mesenchymal Stem Cell Paracrine Effects, Kristin Luther

Dissertations

Changes in gene expression and protein levels are an important aspect of cardioprotection in which short non-coding RNA known as miRNA may play a key regulatory role. We investigated the functions of several miRNAs in the context of two cardioprotective stimuli, ischemic preconditioning (IPC) and mesenchymal stem cell (MSC) paracrine effects. We hypothesized that downregulation of a set of miRNAs (miR-148a/b, miR-30b, and let-7a*) augments expression of protective heat shock proteins during IPC, and that MSC exosomes transfer miR-21 to cardiomyocytes, resulting in downregulation of pro-apoptotic genes and reduction of infarct size.

IPC increased the level of Hsp70, Hsp90 ...


Development Of "Inside-Out" Pegylated Crosslinked Hemoglobin Polymers: Novel Hemoglobin-Based Oxygen Carriers (Hboc), Kyle Douglas Webster Jan 2016

Development Of "Inside-Out" Pegylated Crosslinked Hemoglobin Polymers: Novel Hemoglobin-Based Oxygen Carriers (Hboc), Kyle Douglas Webster

Dissertations

The development of an effective blood substitute is urgent due to increasingly common blood shortages, the need to type-match donated blood, and communicable diseases (e.g. HIV) posing risks for blood transfusions around the world. There have been many attempts at creating hemoglobin-based oxygen carriers (HBOC) using a variety of techniques centered around the use of polyethylene glycol (PEG) conjugated to hemoglobin (Hb) tetramers. A novel method, “Inside-Out” PEGylation, has been developed by our lab to produce a polyethylene glycol crosslinked hemoglobin (PEG XL-Hb) polymer. This method utilizes a single PEG backbone that is surrounded by multiple proteins, instead of ...


Role Of Pkc Delta In Uv Radiation Dna Damage Repair, Gargi Patil Jan 2016

Role Of Pkc Delta In Uv Radiation Dna Damage Repair, Gargi Patil

Master's Theses

DNA damage caused by ultraviolet radiation (UV), such as cyclobutane pyrimidine dimers (CPD), is repaired by the nucleotide excision repair (NER) pathway. When NER is defective, DNA damage is not repaired, leading to mutations and skin cancer. After DNA damage, the cell cycle is halted at various checkpoints to allow time for repair of the damage and maintain genomic integrity, however little is known about the coordination between NER DNA damage repair and cell cycle halting at checkpoints after DNA damage. Protein kinase C δ (PKCδ) plays major role in apoptosis and maintains the G2/M checkpoint in response to ...


An Analytical Method For Detecting Toxic Metal Cations Using Cyclotriveratrylene Derivative Capped Gold Nanoparticles, Zachary R. Osner, Richard C. Holz, Daniel P. Becker Ph.D. Sep 2015

An Analytical Method For Detecting Toxic Metal Cations Using Cyclotriveratrylene Derivative Capped Gold Nanoparticles, Zachary R. Osner, Richard C. Holz, Daniel P. Becker Ph.D.

Chemistry: Faculty Publications and Other Works

Cyclotriveratrylene-oxime (CTV-oxime) derivatives that terminate with a dithiolate linker were synthesized enabling the supramolecular scaffold to adhere to gold nanoparticles (AuNPs) with the bowl-shaped cavity of the CTV scaffold exposed for utilization in host–guest chemistry. Exposure of these CTV functionalized AuNPs to varying concentrations of di- and trivalent metal cations resulted in the formation of large CTV-AuNP polymeric clusters and an accompanying a shift in the plasmon resonance. These interactions between the CTV-AuNPs and the metal cations in solution provides proof-of-concept that supramolecular functionalized AuNPs can be used as a simple and straightforward, on-site detection system for toxic metal ...


Metal-Free Tandem Beckmann–Electrophilic Aromatic Substitution Cascade Affording Diaryl Imines, Ketones, Amines, And Quinazolines, Samuel Sarsah, Marlon R. Lutz Jr., Kailyn Chichi Bobb, Daniel Becker Aug 2015

Metal-Free Tandem Beckmann–Electrophilic Aromatic Substitution Cascade Affording Diaryl Imines, Ketones, Amines, And Quinazolines, Samuel Sarsah, Marlon R. Lutz Jr., Kailyn Chichi Bobb, Daniel Becker

Chemistry: Faculty Publications and Other Works

A cascade reaction sequence involving a Beckmann rearrangement on benzophenone oxime followed by an electrophilic aromatic substitution (EAS) on the intermediate nitrilium ion affords N-phenyl diaryl imines that may then be hydrolyzed to ketones, or reduced to the corresponding amines. Reaction with benzonitrile afforded 2,4-diphenylquinazoline through a Beckmann–Ritter–EAS cascade.


Emetine As An Anti-Cancer Therapeutic In Bladder Cancer, Valerie Davidson Jan 2015

Emetine As An Anti-Cancer Therapeutic In Bladder Cancer, Valerie Davidson

Master's Theses

Bladder cancer is a serious health concern among the older population, as it is responsible for thousands of deaths annually in the United States. Patients that are diagnosed with muscle-invasive disease have a 5-year survival rate of only 20 percent. Additionally, muscle-invasive disease has a high metastatic potential; half of all patients develop metastatic disease within 3 years. Patients with muscle-invasive disease are presented with few treatment options aside from surgery. The current standard of care is a chemotherapeutic combination therapy of cisplatin and gemcitabine. This therapy is highly toxic, and due to the high instance of co-morbidities in these ...


The Endosomal Sorting Complex Required For Transport Pathway Mediates Chemokine Receptor Cxcr4 Akt Signaling By Promoting Lysosomal Degradation Of Mtor Antagonist Deptor, Rita Ramkaran Verma Jan 2015

The Endosomal Sorting Complex Required For Transport Pathway Mediates Chemokine Receptor Cxcr4 Akt Signaling By Promoting Lysosomal Degradation Of Mtor Antagonist Deptor, Rita Ramkaran Verma

Dissertations

The chemokine receptor CXCR4 is a member of the G protein-coupled receptor (GPCR) family. The cognate ligand for CXCR4 is the C-X-C chemokine known as CXCL12. The CXCL12/CXCR4 signaling axis is essential for a number of developmental processes including organogenesis, vascularization of the GI tract and hematopoiesis. Dysregulated CXCR4 signaling is also implicated in a variety of pathological conditions such as WHIM (Warts, Hypogammaglobunemia, Infections and myelokathexis) syndrome, cardiovascular disease and cancer. Despite its role in several pathologies, the molecular mechanisms mediating CXCR4 signaling are not completely understood. Upon CXCL12 binding to CXCR4, several signaling pathways are activated including ...