Amino Acids, Peptides, and Proteins Commons^™

Exploring The Design Space Of Antifungal Peptides, Miryam Kikhwa

Seton Hall University Dissertations and Theses (ETDs)

The synthesis, characterization, and evaluation of antifungal activity of peptides FQ15 and FG10 will be conducted to address the hypothesis. The hypothesis of this thesis is that a peptide with similar properties to AS15 would have similar activity against Cryptococcus neoformans. This study addresses the challenge of drug- resistant microbes by developing inhibitors targeting lipid flippase and exploring their potential as antimicrobial agents against Cryptococcus neoformans. Chapter 1 provides a historical context of the background on the development of antimicrobials and common antifungal treatments, as well as an introduction about C. neoformans and its resistance mechanism. Chapter 2 introduces the …

Quantum Dots' Toxicity: A Multi-Level Investigation On The Impact Of Quantum Dots On The Actin Cytoskeleton, Nhi Le

MSU Graduate Theses

Quantum dots (QDs) are fluorescence nanomaterials with unique optical and physical properties. As such, they are highly sought after for their potential use in several biomedical and industrial applications. Despite their vast potential, recent studies have suggested that quantum dots are toxic to cells. Yet, the mechanism of quantum dots’ toxicity remains unclear. As such, my thesis aims to comprehensively examine the mechanism of quantum dots’ toxicity, emphasizing how quantum dots disrupt the actin cytoskeleton. In this study, I used RNA sequencing and mass spectrometry to investigate the influence of CdSe/ZnS QDs on the transcriptomic proteomic level of Saccharomyces cerevisiae …

Reactive Chemistries For Protein Labeling, Degradation, And Stimuli Responsive Delivery, Myrat Kurbanov

Doctoral Dissertations

Reactive chemistries for protein chemical modification play an instrumental role in chemical biology, proteomics, and therapeutics. Depending on the application, the selectivity of these modifications can range from precise modification of an amino acid sequence by genetic manipulation of protein expression machinery to a stochastic modification of lysine residues on the protein surface. Ligand-Directed (LD) chemistry is one of the few methods for targeted modification of endogenous proteins without genetic engineering. However, current LD strategies are limited by stringent amino acid selectivity. To bridge this gap, this thesis focuses on the development of highly reactive LD Triggerable Michael Acceptors (LD-TMAcs) …

Nanodiscs: A Novel Approach To The Study Of The Methionine Abc Transporter System, Michael T. Winslow

Master's Theses

Membrane transporter proteins play the vital role of moving compounds in and out of the cell and are essential for all living organisms. ATP Binding Cassette (ABC) family transporters function both as importers and exporters in prokaryotes. MetNI is an E. coli Type I ABC transporter responsible for the uptake of methionine into the cytosol from the cell periplasmic space through the cell membrane to maintain intracellular methionine pools. ABC transporters, like other membrane proteins, are most often mechanistically and structurally studied in vitro, solubilized by detergents. However, detergent micelles may affect the conformational changes of membrane proteins relative to …

Synthesis, Characterization And Biological Evaluation Of Polyarginine Derived Bone-Targeting Peptides, Gina L. Antuono

Seton Hall University Dissertations and Theses (ETDs)

Osteoblast-targeting peptides in the treatment of bone disease is a new and novel approach to offering effective treatment of various cancers and can be used in bio-medical, medicinal chemistry and biotechnology applications. By targeting adhesion proteins produced by osteoblast cells, certain cancers which migrate and metastasize to the bone may be more effectively treated. An osteoblast-targeting peptide composed of Ser-Asp-Ser-Ser-Asp (SDSSD) which selectively binds to osteoblast cells via periostin has recently been identified. This peptide was functionalized with polyurethane, generating nanomicelles which encapsulated RNA for the therapeutic treatment of osteoporosis. This study has served as the basis for the research …

Apoptosis Induction In Jurkat T-Lymphocytes By Proton Pump Inhibitors (Ppis), Shreya Murali, Randall Reif

Student Research Submissions

Apoptosis, commonly known as programmed cell death, constantly occurs in humans. As a cancer cell increases in acidity, apoptosis is induced. In healthy cells, proton pump proteins allow for H⁺ ions to permeate cellular membranes, regulating pH. However, proton pump inhibitors (PPIs), such as omeprazole, prevent proton movement. In previous studies, omeprazole induced cell death in Jurkat T lymphocytes; however, there was no confirmation of whether the cells died through apoptosis, or through necrosis, where the cell bursts. By using Annexin-V staining, the effects of omeprazole, dexlansoprazole, and esomeprazole on apoptosis induction can be measured. Cell death was observed …

Leveraging Bio-Inspired Molecules For Cancer Theranostics, Douglas S. Macpherson

Dissertations, Theses, and Capstone Projects

A variety of molecules can be radiolabeled and delivered to a cancer site for the purposes of diagnostics and therapy. Among the most promising of tumor targeting molecules are peptides and antibodies. These bio-inspired molecules can be designed and synthesized to target and respond to cancer cells based on the properties of those cells. Matrix metalloproteinase (MMP) enzymes are over-expressed by some metastatic cancers, in which they are responsible for the degradation and remodeling of the extracellular matrix. In recent years, MMPs have emerged as promising targets for enzyme-responsive diagnostic probes because oligopeptides can be designed to be selectively hydrolyzed …

Identification Of Novel Biosynthetic Gene Clusters Encoding For Polyketide/Nrps-Producing Chemotherapeutic Compounds From Marine-Derived Streptomyces Hygroscopicus From A Marine Sanctuary, Hannah Ruth Flaherty

Honors Theses and Capstones

Nearly one out of six deaths in 2020, around ten million people, were caused by cancer, making it a leading cause of death worldwide (WHO, 2022). This major public health issue, in addition to the rise of multidrug-resistant (MDR) pathogens, provides a high demand for the discovery of new pharmaceutical drugs to be used clinically to treat these conditions. The Streptomyces genus accounts to produce 39% of all microbial metabolites currently approved for human health, indicating its potential as an important species to study for antimicrobial and anticancer agents. The long linear genome of Streptomyces contains specialized sequences known as …

Protacs – A Novel And Rapidly Developing Field Of Targeted Protein Degradation, Hannah R. Gatley

Theses and Dissertations

There is a continued need for new technology and strategies for tackling cancer and other diseases, and within the current century a novel therapeutic strategy has emerged in the realm of targeted protein degradation called Proteolysis-Targeting Chimeras (PROTACs). This technology specifically targets and degrades disease-causing proteins via the ubiquitin-proteasome system, and has seen an explosion of research and intrigue in both academia and industry over the past two decades. The diversity of PROTAC classes based on the E3 ligase recruiting ligand and the target protein allows for a universal molecular structure that can be customized for a specific target and …

Interactions Between Hiv And Opioids On Antiretroviral Accumulation, The Blood Brain Barrier, And The Inflammatory Response In The Brain., Kara Rademeyer

Theses and Dissertations

The complex mechanisms related to HIV infection, neurodegeneration, and chronic neuroinflammation collectively describe neuroHIV (Hauser et al. 2007; Chang et al. 2014; Smith et al. 2014). Specifically, opioid abuse, poor penetration of antiretroviral (ARV) drugs, chronic inflammation and neuronal injury/degeneration are all implicated in neuroHIV (Fantuzzi et al. 2003; Letendre et al. 2004; Verani et al. 2005; Duncan and Sattentau 2011; Hong and Banks 2015; Simoes and Justino 2015; Olivier et al. 2018; Murphy et al. 2019; Osborne et al. 2020). For the first time, we demonstrate that morphine, fentanyl, and methadone in vivo alter the brain accumulation of ARVs, …

Identification Of The Type Eleven Secretion System (T11ss) And Characterization Of T11ss-Dependent Effector Proteins, Alex S. Grossman

Doctoral Dissertations

Host-associated microbes live in dangerous environments as a result of host immune killing, nutrient provisioning, and physiological conditions. Bacteria have evolved a host of surface and secreted proteins to help interact with this host environment and overcome nutrient limitation. The studies included within this dissertation describe the identification of a novel bacterial secretion system which has evolved to transport these symbiosis mediating proteins. This system, termed the type eleven secretion system (T11SS), is present throughout the Gram negative phylum Proteobacteria, including many human pathogens such as Neisseria meningitidis, Acinetobacter baumanii, Haemophilus haemolyticus, and Proteus vulgaris. Furthermore, …

Biomedical Applications Of Protein Films And Polymeric Nanomaterials, Sanjana Gopalakrishnan

Doctoral Dissertations

Biomaterials are widely applied for the diagnosis and treatment of numerous diseases. In addition to fulfilling specific biological functions, biomaterials must also be non-toxic, biocompatible, and sterilizable to be regarded as safe-for-use. Polymers are excellent candidates for fabricating functional biomaterials due to their wide availability and varied properties and may be natural or synthetic. Polymer precursors are fabricated into coatings, foams, scaffolds, gels, composites, and nanomaterials for several biomedical applications. This dissertation focuses on two types of polymeric biomaterials – protein-based materials and synthetic polymeric nanoparticles. Proteins are biopolymers that naturally occur with a variety of structural and functional properties. …

Controlling Myosin’S Function Via Interactions Between The Substrate And The Active Site, Mike K. Woodward

Doctoral Dissertations

Molecular motors, such as myosin, have evolved to transduce chemical energy from ATP into mechanical work to drive essential cellular processes, from muscle contraction to vesicular transport. Dysfunction in these motors is a root cause of many pathologies necessitating the application of intrinsic control over molecular motor function. We hypothesized that altering the myosin’s energy substrate via minor positional changes to the triphosphate portion of the molecule will allow us to control the protein and affect its in vitro function. We utilized positional isomers of a synthetic non-nucleoside triphosphate, azobenzene triphosphate, and assessed whether myosin’s force- and motion-generating capacity could …

Expression And Purification Of The Bacterial Protein Curli Csga And Its Cross-Interactions With Amyloid-B, Leah Grace Cantrell

Honors Theses

One of the main causes of neurodegenerative diseases is aggregation of amyloid proteins that are toxic to the neurons. Proteins like amyloid-β (Aβ) and α-syneuclein (α-syn) form hallmark aggregate lesions that contribute to pathological processes in the brain in Alzheimer and Parkinson’s patients, respectively. Recent ground-breaking studies have suggested a link between the microbiota of the gut and neurodegenerative diseases, called the “gut-brain axis.” It has been long known that the protein, CsgA found in many enteric bacteria, forms amyloid fibers of its own called Curli. Curli fibrils are a structural component of bacterial colonies and maintain the integrity of …

Flippase Inhibitors As Antimicrobial Agents, Robert Tancer

Seton Hall University Dissertations and Theses (ETDs)

Drug resistant microbes are a considerable challenge for modern medicine to overcome. The research described in this dissertation involved development of lipid flippase inhibitors and investigating their potential as antimicrobial agents against various drug resistant microbes. The microbes primarily investigated were methicillin resistant Staphylococcus aureus (MRSA) & Cryptococcus neoformans. Chapter 1 reviews the historical perspective and summarizes the current state of the field of research. In Chapter 2, the design space of an antimicrobial peptide known as humimycin was explored and the effects of modifications on its structure were observed against MRSA. Several key observations resulted. Most notably, the …

Hyper Stable Variants Of Fgf-1-Fgf-2 Dimer, Madison Shields Mcclanahan

Chemistry & Biochemistry Undergraduate Honors Theses

Fibroblast Growth Factors (FGFs), including FGF-1 and FGF-2, are proteins that play a crucial role in cell proliferation, cell differentiation, cell migration, and tissue repair. FGF-1 and FGF-2 are useful in accelerating the healing process in the human body; however, these proteins are naturally thermally unstable, resulting in a relatively low half-life in vivo. 1,8 In efforts to improve the stability of this protein, FGF-1 and FGF-2 proteins are engineered by combining the amino acid sequences of the two proteins to form a heterodimer and obtain novel properties. These two FGF variants are chosen for their specific wound healing capabilities. …

Deciphering Protein Higher-Order Structure And Interactions Via Diethylpyrocarbonate Labeling-Mass Spectrometry, Xiao Pan

Doctoral Dissertations

The study of protein higher-order structures is vital because it is closely related to the investigation of protein folding, aggregation, interaction and protein therapeutics. Consequently, numerous biochemical and biophysical tools have been developed to study protein higher-order structures in many different situations. The combination of covalent labeling (CL) and mass spectrometry (MS) has emerged as a powerful tool for studying protein structures and offers many advantages over other traditional techniques, such as better structural coverage, high throughput, high sensitivity, and the ability to study proteins in mixtures. This dissertation focuses on diethylpyrocarbonate (DEPC) as an effective CL reagent that can …

Protein Structure And Interaction: The Role Of Aromatic Residues In Protein Structure And Interactions Between Pyridoxine 5'-Phosphate Oxidase/Dopa Decarboxylase, Mohammed H. Al Mughram

Theses and Dissertations

Naturally developed proteins are capable of carrying out a wide variety of molecular functions due to their highly precise three-dimensional structures, which are determined by their genetically encoded sequences of amino acids. A thorough knowledge of protein structures and interactions at the atomic level will enable researchers to get a deep foundational understanding of the molecular interactions and enzymatic processes required for cells, resulting in more effective therapeutic interventions. This dissertation intends to use structural knowledge from solved protein structures for two distinct objectives.

In the first project, we conducted a bioinformatics structural analysis of experimental protein structures using our …

Antimicrobial Activity Of Bacterial Virus Components: An Empirical Investigation Of The Killing Capacity Of Toxins From Burkholderia, Kyle Walny

Honors Projects

Given the growing issue in healthcare of antibiotic resistance, effective and safe alternative treatment methods are required. One of these possible alternative treatment methods is bacteriotoxins including bacteriocins and tailocins. The focus of this study is a bacteriotoxin from Burkholderia cenocepacia (ATCC 25608), which was induced for toxin using a modified UV light induction procedure and tested against a variety of Pseudomonas and Burkholderia for its killing capacity. Various other pathogenic strains were then induced with UV light and tested. The results showed that the toxin from ATCC 25608 was very effective against most of the Burkholderia tested and warrants …

A Review Of Calcineurin Biophysics With Implications For Cardiac Physiology, Ryan B. Williams

Theses and Dissertations

Calmodulin is a prevalent calcium sensing protein found in all cells. Three genes exist for calmodulin and all three of these genes encode for the exact same protein sequence. Recently mutations in the amino acid sequence of calmodulin have been identified in living human patients. Thus far, patients harboring these mutations in the calmodulin sequence have only displayed an altered cardiac related phenotype. Calcineurin is involved in many key physiological processes and its activity is regulated by calcium and calmodulin. In order to assess whether or not calcineurin contributes to calmodulinopathy (a pathological state arising from dysfunctional calmodulin), a comprehensive …

Exogenous Surfactant As A Delivery Vehicle For Intrapulmonary Therapeutics, Brandon J. Baer

Electronic Thesis and Dissertation Repository

As an organ system, the lung has unique advantages and disadvantages for direct drug delivery. Its contact with the external environment allows for the airways to be easily accessible to intrapulmonary delivery. However, its complex structure, which divides into more narrow airways with each branch, can make direct delivery to the remote alveoli challenging. The objective of this thesis was to overcome this issue by using exogenous surfactant, a lipoprotein complex used to treat neonatal respiratory distress syndrome, as a carrier for pulmonary therapeutics. It was hypothesized that therapeutics administered with a surfactant vehicle would display enhanced delivery to the …

Synthesis, Characterization And Applications Of Peptide-Coated Nanoparticles, Mina Sadat Poursharifi

Dissertations, Theses, and Capstone Projects

Ovarian Cancer (OC) is the most lethal female malignancy worldwide, mainly due to its high recurrence rate and poor diagnosis. Most patients present with late stage of the disease, and less than 25% of patients survive the five years mark. Nanotherapy provides significant and unique benefits for drug efficacy, as nanoparticles (NPs) can increase the solubility, bioavailability, and permeability of many potent drugs. Poly(lactic-co-glycolic acid) (PLGA) is one of the most successful biodegradable polymers used in NPs formulations, mainly due to its biocompatibility and biodegradability. Polyethylene glycol (PEG) is one of the most commonly used moieties to prolong the NPs …

Molecular Dynamics Simulations Of Self-Assemblies In Nature And Nanotechnology, Phu Khanh Tang

Dissertations, Theses, and Capstone Projects

Nature usually divides complex systems into smaller building blocks specializing in a few tasks since one entity cannot achieve everything. Therefore, self-assembly is a robust tool exploited by Nature to build hierarchical systems that accomplish unique functions. The cell membrane distinguishes itself as an example of Nature’s self-assembly, defining and protecting the cell. By mimicking Nature’s designs using synthetically designed self-assemblies, researchers with advanced nanotechnological comprehension can manipulate these synthetic self-assemblies to improve many aspects of modern medicine and materials science. Understanding the competing underlying molecular interactions in self-assembly is always of interest to the academic scientific community and industry. …

The Structural And Functional Role Of Photosensing In Rgs-Lov Proteins, Zaynab Jaber

Dissertations, Theses, and Capstone Projects

Light provides organisms with energy and spatiotemporal information. To survive and adapt, organisms have developed the ability to sense light to drive biochemical effects that underlie vision, entrainment of circadian rhythm, stress response, virulence, and many other important molecularly driven responses. Blue-light sensing Light-Oxygen-Voltage (LOV) domains are ubiquitous across multiple kingdoms of life and modulate various physiological events via diverse effector domains. Using a small molecule flavin chromophore, the LOV domain undergoes light-dependent structural changes leading to activation or repression of these catalytic and non-catalytic effectors. In silico analyses of high-throughput genomic sequencing data has led to the marked expansion …

Gene Expression Profiling Of Mapk Pathway Inhibitor Resistance In Cutaneous Melanoma: Can Bioinformatics Be Used To Select Better Melanoma Cell Lines?, Stephen Luebker

Theses & Dissertations

Melanoma is the deadliest form of skin cancer, and incidence has continued to increase. Half of all melanomas have a BRAF V600E mutation and respond to MAPK pathway inhibitors, including BRAF inhibitor therapy or BRAF/MEK inhibitor combination therapy, but nearly all patients develop treatment resistance. Melanoma cell lines produce variable results as models of MAPK pathway inhibitor resistance. To better understand how the genomic similarity of a melanoma cell line to patient-derived tumors affects resistance mechanisms, differences in DNA mutations and copy-number alterations were compared between melanoma cell lines profiled by the Cancer Cell Line Encyclopedia and cutaneous melanoma tumors …

Anti-Inflammatory And Chemopreventive Activity Of Lunasin From Tofu Whey For The Management Of Gastrointestinal Diseases, Cindy Andrea Nieto Veloza

Doctoral Dissertations

Gastrointestinal diseases such as inflammatory bowel diseases (IBD) and colorectal cancer (CRC) are pathological conditions associated with chronic inflammation, characterized by intestinal damage, debilitating symptoms, and detrimental health consequences. The increased risk of CRC in IBD patients, and the adverse effects associated with current therapeutic strategies, point out the need for safer alternatives to reduce chronic inflammation in the bowel. Lunasin is a bioactive peptide naturally occurring in soybeans, with chemopreventive and anti-inflammatory properties demonstrated in several extra-intestinal diseases. However, to date, there is no evidence of the biological activity of lunasin on the gastrointestinal tract as a target site. …

Toxic Effect Of Crotalus Adamanteus Acidic Phospholipase A2 On Mcf-7 Cell Line, Daniel J. Petra

Honors Thesis

We are investigating the effect of Crotalus adamanteus acidic phospholipase A₂ on MCF-7 cells using the MTS assay. Understanding these interactions and isolated effects is critical to developing new ways to treat envenomation. By understanding the effects of individual toxins within a whole venom, we are set to better understand the effects of the whole venom and investigate synergistic actions between venom toxins. In this paper, we are quantifying the amount of MCF-7 cell death caused by Crotalus adamanteus phospholipase A₂ on MCF-7 using the MTS assay. Analysis of the amount of cells death caused by the phospholipase …

Amphiphilic Cell-Penetrating Peptides Containing Natural And Unnatural Amino Acids As Drug Delivery Tools And Antimicrobial Agents, David Salehi

Pharmaceutical Sciences (MS) Theses

Cell-penetrating peptides containing arginine as positively charged residues and tryptophan or diphenylalanine as hydrophobic residues were synthesized. The synthesis was accomplished through the Fmoc solid-phase peptide synthesis in the presence of HBTU and DIPEA. The side-chain protected linear peptides were cleaved from the resin and cyclized in the presence of DIC and HOAt in the solution phase overnight. MALDI-TOF mass spectrometry was used to characterize the peptides.

The cytotoxicity of the synthesized peptides was determined in CCRF-CEM (human, lymphoblast peripheral blood), and HEK-293 (human, embryonic epithelial kidney healthy) cells using the MTS assay. A concentration of 10 µM was found …

Cloning And Functional Characterizations Of Circular Rnas From The Human Mapt Locus, Justin R. Welden

Theses and Dissertations--Molecular and Cellular Biochemistry

Under pathophysiological conditions, the microtubule protein tau (MAPT) forms neurofibrillary tangles that are the hallmark of sporadic Alzheimer’s disease as well as familial frontotemporal dementias linked to chromosome 17 (FTDP-17). In this work, I report that MAPT forms circular RNAs through backsplicing of exon 12 to either exon 10 or exon 7 (12→10; 12→7), and that these circular RNAs are translated into proteins.

Using stable cell lines overexpressing the circular tau RNAs 12→7 and 12→10, we have discovered that the tau circular RNA 12→7 is translated in a rolling circle, giving rise to multiple proteins. This circular RNA …

Structural Characterization And In Vitro Antiproliferative Activity Of Non-Specific Lipid Transfer Protein 1 (Nsltp1) From Fennel (Foeniculum Vulgare) Seeds, Mekdes Megeressa

Pharmaceutical Sciences (PhD) Dissertations

Non-specific lipid transfer proteins (nsLTPs) are cationic proteins involved in intracellular lipid shuttling, in growth and reproduction, as well as in defense against pathogenic microbes. Even though the primary and spatial structures of some nsLTPs from different plants indicate their similar features, they exhibit distinct lipid-binding specificities signifying their various biological roles that dictate further structural study. The present study determined the complete amino acid sequence, in silico 3D structure modeling, and in vitro antiproliferative activity of nsLTP1 from fennel (Foeniculum vulgare) seeds.

Fennel is a member of the family Umbelliferae (Apiaceae) native to southern Europe and the …