Amphiphilic Cell-Penetrating Hybrid Cyclic-Linear Peptides As A Drug Delivery System,
2019
Chapman University
Amphiphilic Cell-Penetrating Hybrid Cyclic-Linear Peptides As A Drug Delivery System, Saghar Mozaffari
Pharmaceutical Sciences (PhD) Dissertations
A number of cyclic peptides containing a positively charged ring composed of arginine residues attached to hydrophobic tail made of tryptophan residues through a lysine linker namely [R5K]W5, [R6K]W5, [R5K]W6, [R7K]W5, [R5K]W7, [R6K]W6, and [R7K]W7 were synthesized and evaluated as molecular transporters. The peptides were evaluated for their ability to deliver, fluorescence-labeled cell-impermeable negatively charged phosphopeptide (F′-GpYEEI), and fluorescent labeled anti-HIV drugs (F′-FTC and F′-d4T). The results indicated that the presence of positively …
Alanyl-Trna Synthetase Quality Control Prevents Global Dysregulation Of The Escherichia Coli Proteome,
2019
The Ohio State University
Alanyl-Trna Synthetase Quality Control Prevents Global Dysregulation Of The Escherichia Coli Proteome, Paul Kelly, Nicholas Backes, Kyle Mohler, Christopher Buser, Arundhati Kavoor, Jesse Rinehart, Gregory Phillips, Michael Ibba
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
Mechanisms have evolved to prevent errors in replication, transcription, and translation of genetic material, with translational errors occurring most frequently. Errors in protein synthesis can occur at two steps, during tRNA aminoacylation and ribosome decoding. Recent advances in protein mass spectrometry have indicated that previous reports of translational errors have potentially underestimated the frequency of these events, but also that the majority of translational errors occur during ribosomal decoding, suggesting that aminoacylation errors are evolutionarily less tolerated. Despite that interpretation, there is evidence that some aminoacylation errors may be regulated, and thus provide a benefit to the cell, while others …
Alzheimer's And Amyloid Beta: Amyloidogenicity And Tauopathy Via Dyshomeostatic Interactions Of Amyloid Beta,
2019
Liberty University
Alzheimer's And Amyloid Beta: Amyloidogenicity And Tauopathy Via Dyshomeostatic Interactions Of Amyloid Beta, Jordan Tillinghast
Senior Honors Theses
This paper reviews functions of Amyloid-β (Aβ) in healthy individuals compared to the consequences of aberrant Aβ in Alzheimer’s disease (AD). As extraneuronal Aβ accumulation and plaque formation are characteristics of AD, it is reasonable to infer a pivotal role for Aβ in AD pathogenesis. Establishing progress of the disease as well as the mechanism of neurodegeneration from AD have proven difficult (Selkoe, 1994). This thesis provides evidence suggesting the pathogenesis of AD is due to dysfunctional neuronal processes involving Aβ’s synaptic malfunction, abnormal interaction with tau, and disruption of neuronal homeostasis. Significant evidence demonstrates that AD symptoms are partially …
Production And Purification Of Basic Fibroblast Growth Factor Fused To Two Collagen Binding Domains Expressed In E. Coli Bl21 Using Flask And Fed-Batch,
2019
University of Arkansas, Fayetteville
Production And Purification Of Basic Fibroblast Growth Factor Fused To Two Collagen Binding Domains Expressed In E. Coli Bl21 Using Flask And Fed-Batch, Hazim Aljewari
Graduate Theses and Dissertations
Delivering effective and non-toxic doses of bioactive materials that can aid in activating tissue regeneration to wounded tissue has proven to be an enormous challenge. This study was designed to produce a potential therapeutic recombinant protein by fusing two collagen binding domains to basic fibroblast growth factors (bFGF) through a collagenase cleavage site linker, so it can release the bFGF in a wound site by the action of this enzyme. The novel fusion protein was expressed in Escherichia coli BL-21 (E. coli) using traditional flask shaker and fed-batch cultivation. Cell lysate was purified by FPLC using Immobilized metal affinity chromatography …
Effects Of A Double Mutation In The Heparin Binding Pocket On Hfgf-1,
2019
University of Arkansas, Fayetteville
Effects Of A Double Mutation In The Heparin Binding Pocket On Hfgf-1, Vanessa Weidling
Chemical Engineering Undergraduate Honors Theses
The human acidic fibroblast growth factor (hFGF-1) is a protein that plays an important role in many body processes such as angiogenesis and tissue repair. As such, it has great potential for therapeutic application. However, hFGF-1 is relatively unstable in the body with a significant fraction being denatured at body temperature and pH. It contains a group of positively charged amino acids in close proximity that create an electrostatic strain on the molecule and can lead to denaturation and increased susceptibility to enzymatic digestion. Upon its release from the cell, hFGF-1 binds to the glycosaminoglycan heparin in the extracellular matrix. …
Functional Importance Of Lipin Phosphorylation,
2019
University of Arkansas, Fayetteville
Functional Importance Of Lipin Phosphorylation, Stephanie Elizabeth Hood
Graduate Theses and Dissertations
Highly conserved throughout evolution, lipins are dual functioning proteins found from yeast to humans. Functioning in the cytoplasm as phosphatidate phosphatase enzymes (PAP), lipins produce diacylglycerol that serves as a precursor for neutral fats and membrane phospholipids. Alternatively, nuclear lipins are responsible for the regulation of metabolic genes. Interestingly, both the mammalian lipin 1 paralog and the single Drosophila Lipin ortholog are highly phosphorylated proteins. Target of rapamycin (TOR) has previously been identified as one of the kinases that controls the subcellular localization of both lipin 1 and Drosophila Lipin. However, other serine and threonine kinases are predicted to be …
Probing Of Carbohydrate-Protein Interactions Using Galactonoamidine Inhibitors,
2019
University of Arkansas, Fayetteville
Probing Of Carbohydrate-Protein Interactions Using Galactonoamidine Inhibitors, Jessica B. Pickens
Graduate Theses and Dissertations
Glycoside hydrolases are ubiquitous and one of the most catalytically proficient enzymes known, and thus understanding their mechanisms are crucial. Most research has focused on the interaction of the glycon of substrates and their inhibitors within the active site of glycoside hydrolases. The inhibitors employed to probe these interactions generally had small aglycons (i.e. a hydrogen atom, amidines, small aliphatic groups, or benzyl groups). Here, the interactions of the aglycon with glycoside hydrolases are examined by probing the active sites with a library of 25 galactonoamidines. The studies described in this dissertation aim to increase the understanding of stabilization of …
Toward Understanding The Mechanism Of Protein Targeting In The Chloroplast Signal Recognition Particle Pathway,
2019
University of Arkansas, Fayetteville
Toward Understanding The Mechanism Of Protein Targeting In The Chloroplast Signal Recognition Particle Pathway, Mercede Furr
Graduate Theses and Dissertations
Protein targeting is a vital cellular function. The signal recognition particle (SRP) pathway is a universally conserved targeting system present in the cytosol and used to co-translationally target many proteins to the inner membrane of prokaryotes and the endoplasmic reticulum of eukaryotes. The chloroplast has a homologous SRP system which post-translationally targets light harvesting chlorophyll binding proteins (LHCPs) to the thylakoid membrane for integration. The chloroplast SRP (cpSRP) is a heterodimer with a 54 kDa subunit equivalent to SRP54 in the canonical pathway. In addition, cpSRP contains a novel 43 kDa subunit which is a unique and irreplaceable component. cpSRP43 …
Global Acetylation Dynamics In The Heat Shock Response Of Saccharomyces Cerevisiae,
2019
University of Arkansas, Fayetteville
Global Acetylation Dynamics In The Heat Shock Response Of Saccharomyces Cerevisiae, Rebecca E. Hardman
Graduate Theses and Dissertations
All organisms face a constant barrage of environmental stresses. Single-cell organisms such as Saccharomyces cerevisiae, or common Baker’s yeast, must rely solely on cellular responses in order to survive. This response must occur in a rapid and highly coordinated manner to quickly inhibit all unnecessary processes and shuttle all available resources to those necessary for survival. One method that cells utilize for rapid protein regulation is the use of post-translational modifications. Enzymes within the cell add or remove a variety of chemical modifications, thus altering the local chemical environment of a protein. This creates a conformational change in the protein …
Single Molecule Fluorescence Studies Of Protein Structure And Dynamics Underlying The Chloroplast Signal Recognition Particle Targeting Pathway,
2019
University of Arkansas, Fayetteville
Single Molecule Fluorescence Studies Of Protein Structure And Dynamics Underlying The Chloroplast Signal Recognition Particle Targeting Pathway, Dustin R. Baucom
Graduate Theses and Dissertations
The work presented in this dissertation explores the structural dynamics in the chloroplast signal recognition particle pathway. Findings include cpSRP shows scanning functionality similar to that in the cytosolic SRP with the ribosome. The intrinsically disordered C-terminal tail of the Albino3 protein has some transient secondary structure. Upon binding to cpSRP43 in solution, separate secondary structure formation was identified in the C-terminal tail of Albino3. Finally, to increase efficiency of analyzing fluorescence time traces for this work, a modular software was produced.
Influence Of Single And Multiple Histidine Residues And Their Ionization Properties On Transmembrane Helix Dynamics, Orientations And Fraying,
2019
University of Arkansas, Fayetteville
Influence Of Single And Multiple Histidine Residues And Their Ionization Properties On Transmembrane Helix Dynamics, Orientations And Fraying, Fahmida Afrose
Graduate Theses and Dissertations
Since aromatic and charged residues are often present in various locations of transmembrane helices of integral membrane proteins, their impacts on the molecular properties of transmembrane proteins and their interactions with lipids are of particular interest in many studies. In this work, I used solid-state deuterium NMR spectroscopy in designed model peptide GWALP23 [GGALW(LA)6LWLAGA] with selective deuterium labels to addresses the pH dependence and influence of single and multiple “guest” histidine residues in the orientation and dynamic behaviors of transmembrane proteins. The mutations include Gly to His (G2/22 to H2/22), Trp to His (W5/19 to H5/19) and Leu to His …
A Systematic Comparison Of Lipopolymers For Sirna Delivery To Multiple Breast Cancer Cell Lines: In Vitro Studies,
2019
Chapman University
A Systematic Comparison Of Lipopolymers For Sirna Delivery To Multiple Breast Cancer Cell Lines: In Vitro Studies, Hamidreza Montazeri Aliabadi, Remant Bahadur Kc, Emira Bousoik, Ashley Barbarino, Bindu Thapa, Melissa Coyle, Parvin Mahdipoor, Hasan Uludağ
Pharmacy Faculty Articles and Research
Small interfering RNA (siRNA) therapy is a promising approach for treatment of a wide range of cancers, including breast cancers that display variable phenotypic features. To explore the general utility of siRNA therapy to control aberrant expression of genes in breast cancer, we conducted a detailed analysis of siRNA delivery and silencing response in vitro in 6 separate breast cancer cell models (MDA-MB-231, MDA-MB-231-KRas-CRM, MCF-7, AU565, MDA-MB-435 and MDA-MB-468 cells). Using lipopolymers for siRNA complexation and delivery, we found a large variation in siRNA delivery efficiency depending on the specific lipopolymer used for siRNA complexation and delivery. Some lipopolymers were …
Establishing Computational Approaches Towards Identifying Malarial Allosteric Modulators: A Case Study Of Plasmodium Falciparum Hsp70s,
2019
Rhodes University
Establishing Computational Approaches Towards Identifying Malarial Allosteric Modulators: A Case Study Of Plasmodium Falciparum Hsp70s, Arnold Amusengeri, Lindy Astl, Kevin Lobb, Gennady M. Verkhivker, Özlem Tastan Bishop
Mathematics, Physics, and Computer Science Faculty Articles and Research
Combating malaria is almost a never-ending battle, as Plasmodium parasites develop resistance to the drugs used against them, as observed recently in artemisinin-based combination therapies. The main concern now is if the resistant parasite strains spread from Southeast Asia to Africa, the continent hosting most malaria cases. To prevent catastrophic results, we need to find non-conventional approaches. Allosteric drug targeting sites and modulators might be a new hope for malarial treatments. Heat shock proteins (HSPs) are potential malarial drug targets and have complex allosteric control mechanisms. Yet, studies on designing allosteric modulators against them are limited. Here, we identified allosteric …
How Oxygen Availability Affects The Antimicrobial Efficacy Of Host Defense Peptides: Lessons Learned From Studying The Copper-Binding Peptides Piscidins 1 And 3,
2019
Old Dominion University
How Oxygen Availability Affects The Antimicrobial Efficacy Of Host Defense Peptides: Lessons Learned From Studying The Copper-Binding Peptides Piscidins 1 And 3, Adenrele Oludiran, David S. Courson, Malia D. Stuart, Anwar R. Radwan, John C. Putsma, Myriam L. Cotten, Erin B. Purcell
Chemistry & Biochemistry Faculty Publications
The development of new therapeutic options against Clostridioides difficile (C. difficile) infection is a critical public health concern, as the causative bacterium is highly resistant to multiple classes of antibiotics. Antimicrobial host-defense peptides (HDPs) are highly effective at simultaneously modulating the immune system function and directly killing bacteria through membrane disruption and oxidative damage. The copper-binding HDPs piscidin 1 and piscidin 3 have previously shown potent antimicrobial activity against a number of Gram-negative and Gram-positive bacterial species but have never been investigated in an anaerobic environment. Synergy between piscidins and metal ions increases bacterial killing aerobically. Here, we …
Dormant Pathogenic Cd4(+) T Cells Are Prevalent In The Peripheral Repertoire Of Healthy Mice,
2019
Old Dominion University
Dormant Pathogenic Cd4(+) T Cells Are Prevalent In The Peripheral Repertoire Of Healthy Mice, Anna Cebula, Michal Kuczma, Edyta Szurek, Maciej Pietrzak, Natasha Savage, Wessam R. Elhefnawy, Grzegorz Rempala, Piotr Kraj, Leszek Ignatowicz
Computer Science Faculty Publications
Thymic central tolerance eliminates most immature T cells with autoreactive T cell receptors (TCR) that recognize self MHC/peptide complexes. Regardless, an unknown number of autoreactive CD4+Foxp3− T cells escape negative selection and in the periphery require continuous suppression by CD4+Foxp3+ regulatory cells (Tregs). Here, we compare immune repertoires of Treg-deficient and Treg-sufficient mice to find Tregs continuously constraining one-third of mature CD4+Foxp3− cells from converting to pathogenic effectors in healthy mice. These dormant pathogenic clones frequently express TCRs activatable by ubiquitous autoantigens presented by class II MHCs on conventional dendritic cells, including selfpeptides that select …
The Fitness Landscape Of The African Salmonella Typhimurium St313 Strain D23580 Reveals Unique Properties Of The Pbt1 Plasmid,
2019
University of Liverpool
The Fitness Landscape Of The African Salmonella Typhimurium St313 Strain D23580 Reveals Unique Properties Of The Pbt1 Plasmid, Rocío Canals, Roy R. Chaudhuri, Rebecca E. Steiner, Siân V. Owen, Natalia Quinones-Olvera, Melita A. Gordon, Michael Baym, Michael Ibba, Jay C. D. Hinton
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
We have used a transposon insertion sequencing (TIS) approach to establish the fitness landscape of the African Salmonella enterica serovar Typhimurium ST313 strain D23580, to complement our previous comparative genomic and functional transcriptomic studies. We used a genome-wide transposon library with insertions every 10 nucleotides to identify genes required for survival and growth in vitro and during infection of murine macrophages. The analysis revealed genomic regions important for fitness under two in vitro growth conditions. Overall, 724 coding genes were required for optimal growth in LB medium, and 851 coding genes were required for growth in SPI-2-inducing minimal medium. These …
Chemical Epitope Targeting: Review Of A Novel Screening Technology,
2019
Clark University
Chemical Epitope Targeting: Review Of A Novel Screening Technology, Qurrat Ul-Ain, Rene Kandler, Dylan Gillespie, Arundhati Nag
Scholarly Undergraduate Research Journal at Clark (SURJ)
Chemical Epitope Targeting is a novel technology developed for designing peptide ligands with high affinity and specificity against specific regions of a protein that may be inaccessible to small molecules or antibodies. In this review, we summarize the key steps and significant applications of this technology. Operating on the same principles as antibody-antigen interactions, this technique involves chemically synthesizing the region of interest on the protein, called the epitope, as a polypeptide with a biotin detection tag and a strategically placed alkyne or azide presenting amino acid. The constructed epitope is screened against a comprehensive linear or cyclic One Bead …
Developing A Dissociative Nanocontainer For Peptide Drug Delivery,
2019
CUNY Graduate Center
Developing A Dissociative Nanocontainer For Peptide Drug Delivery, Michael Patrick Kelly
Dissertations, Theses, and Capstone Projects
The potency and specificity of bioactive peptides have propelled these agents to the forefront of pharmacological research. However, delivery of peptides to their molecular target in cells is a major obstacle to their widespread application. A Trojan Horse strategy of packaging a bioactive peptide within a modified protein cage to protect it during transport, and releasing it at the target site, is a promising delivery method. Recent work has demonstrated that the viral capsid of the P22 bacteriophage can be loaded with an arbitrary, genetically-encoded peptide, and externally decorated with a cell-penetrating peptide, such as HIV-Tat, to translocate across in …
Effective Statistical Energy Function Based Protein Un/Structure Prediction,
2019
University of New Orleans
Effective Statistical Energy Function Based Protein Un/Structure Prediction, Avdesh Mishra
LSU New Orleans Theses and Dissertations
Proteins are an important component of living organisms, composed of one or more polypeptide chains, each containing hundreds or even thousands of amino acids of 20 standard types. The structure of a protein from the sequence determines crucial functions of proteins such as initiating metabolic reactions, DNA replication, cell signaling, and transporting molecules. In the past, proteins were considered to always have a well-defined stable shape (structured proteins), however, it has recently been shown that there exist intrinsically disordered proteins (IDPs), which lack a fixed or ordered 3D structure, have dynamic characteristics and therefore, exist in multiple states. Based on …
Short Amylin Receptor Antagonist Peptides Improve Memory Deficits In Alzheimer’S Disease Mouse Model,
2019
University of Alberta
Short Amylin Receptor Antagonist Peptides Improve Memory Deficits In Alzheimer’S Disease Mouse Model, Rania Soudy, Ryoichi Kimura, Aarti Patel, Wen Fu, Kamaljit Kaur, David Westaway, Jing Yang, Jack Jhamandas
Pharmacy Faculty Articles and Research
Recent evidence supports involvement of amylin and the amylin receptor in the pathogenesis of Alzheimer’s disease (AD). We have previously shown that amylin receptor antagonist, AC253, improves spatial memory in AD mouse models. Herein, we generated and screened a peptide library and identified two short sequence amylin peptides (12–14 aa) that are proteolytically stable, brain penetrant when administered intraperitoneally, neuroprotective against Aβ toxicity and restore diminished levels of hippocampal long term potentiation in AD mice. Systemic administration of the peptides for five weeks in aged 5XFAD mice improved spatial memory, reduced amyloid plaque burden, and neuroinflammation. The common residue SQELHRLQTY …
