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Computational Modelling And Design Of Antibodies: Benefits From Analysis Of Their Unique Structural Motifs, Katherine M. Mccoy

Dartmouth College Ph.D Dissertations

The complexes that antibodies make with their binding partners, or antigens, are especially valuable to be able to predict and modify due to their unique role in the immune system. Yet, they present significant challenges to computational methods of both modelling and design. Antibodies are unlike most other proteins in that they are composed of a scaffold region, which is a highly conserved structure that is largely the same between antibodies of the same class, and Complementary Determining Regions (CDRs), which are comprised of hypervariable loops that largely determine their binding motifs. Additionally, antibodies and their antigens do not co-evolve …

Mechanical Properties Of Natural Osmia Lignaria Silk And Recombinant Expression Of The Silk Proteins, Jackson Morley

Undergraduate Honors Capstone Projects

The use of petroleum-based plastic and the subsequent waste has led researchers to explore alternatives in the form of biopolymers. Spider silk and hagfish intermediate filaments show the potential to be advantageously utilized in textile and biomedical industries. Bee silk is a sparsely studied biopolymer that has shown potential to be added to these other impressive biopolymers. Osmia lignaria, is a solitary bee native to the western United States. Silk from these bees can be isolated while the larvae are spinning their silk. The silk from these bees has been mechanically tested for strength, stress, strain, and elasticity. Cocoon …

Fundamental Study Of Ionic Liquid Physicochemical Effects On Thermal Stability Of Model Biological Macromolecules, Austin Keith Clark

Theses and Dissertations

Ionic Liquids (ILs) are substances with a unique physical attribute compared to that of solid ionic salts. At room temperature, ILs are molten salts that have a variety of physical effects that can play a role in their impact on other molecules, as solvents or solutes. They can play the role of the solvent in a variety of applications, from biofuels to organic catalysis or as excipients in pharmaceutical formulations. These ILs have a desirable use as solvents due to their ability to be tunable substances. Changing the cation or anion of the IL causes a change in its physical …

Protein Stability In Solution And In The Gas Phase., Yousef Haidar

Electronic Thesis and Dissertation Repository

Electrospray Ionization mass spectrometry (ESI-MS) is widely used for probing proteins, yet many aspects of this technique remain elusive. Using MS, ion mobility spectrometry (IMS), and circular dichroism (CD) spectroscopy, this thesis sheds light on the stability differences of proteins in the gas phase and solution. After a general introduction (Chapter 1), Chapter 2 scrutinizes some aspects of native ESI. Our data highlight the significance of cone voltage in maintaining a native-like fold and show the advantage of using NH₄Ac in protein experiments. Chapter 3 focuses on hydrogen/deuterium exchange (HDX)-MS. Several studies have reported that D₂O …

Mutating Tetur02g09850 Originated From Spider Mites To Enhance Crystallization, Hayley Cash

Senior Theses

This study aimed to explain and adequately utilize several common biochemical laboratory techniques to mutate a portion of the nucleic acid sequence within a specific protein. This protein, referred to as Tetur02g09850 is originated from Tetranychus Urticae, or the Two-Spotted Spider Mite. This mite causes excessive damage to crops and is known to be extremely resistant to most common pesticides. For this reason, understanding the protein structure could be used to explain this acaricide resistance and aid in the development of more effective pesticides. Some of the testing utilized was site-directed mutagenesis, IMAC and gel filtration for protein purification, gel …

Supertertiary Structural Dynamics Modulate Function In Postsynaptic Density Protein 95, George L. Hamilton Iii

All Dissertations

Proteins, RNA, and DNA serve as the primary sub-cellular machinery that give rise to the necessary functions of life. The long-standing paradigm has been that the structures of biomolecules, or the arrangement of the subunits that make up a biomolecule, determine biological function. However, biomolecules are not static objects. Instead, they often undergo structural rearrangements that are crucial to enabling and regulating their functions. In my thesis I present several studies of the interplay between the structures, dynamics, and functions of biomolecules that combine experimental fluorescence spectroscopy and computational methods to probe these systems at the single-molecule level. In particular, …

Molecular Simulation Of Rna Conformational Dynamics : An Example Of Micro-Rna Targeting Messenger Rna : Mir-34a-Msirt1, Parisa Ebrahimi

Legacy Theses & Dissertations (2009 - 2024)

MicroRNA (miRNA), as a distinct class of biological regulators and a ”guide” member of non-coding RNA-protein complexes (RNPs), regulates more than 60% of protein-coding genes expression through base-pairing with targeted messenger RNA (mRNA) in the RNA-Induced Silencing Complex (RISC). Most of miRNAs identified in human, are conserved in other animals, which have preferentially conserved interaction sites particularly in 3’ untranslated regions (3’UTRs) of many human messenger mRNAs.The capability of a single miRNA to target more than hundreds of mRNAs, suggests that miRNAs influence essentially all developmental process and diseases, which also makes them interesting candidates as therapeutics agents. The primary …

Molecular Simulation Of Rna Conformational Dynamics : An Example Of Micro-Rna Targeting Messenger Rna : Mir-34a-Msirt1, Parisa Ebrahimi

Legacy Theses & Dissertations (2009 - 2024)

MicroRNA (miRNA), as a distinct class of biological regulators and a ”guide” member of non-coding RNA-protein complexes (RNPs), regulates more than 60% of protein-coding genes expression through base-pairing with targeted messenger RNA (mRNA) in the RNA-Induced Silencing Complex (RISC). Most of miRNAs identified in human, are conserved in other animals, which have preferentially conserved interaction sites particularly in 3’ untranslated regions (3’UTRs) of many human messenger mRNAs.The capability of a single miRNA to target more than hundreds of mRNAs, suggests that miRNAs influence essentially all developmental process and diseases, which also makes them interesting candidates as therapeutics agents. The primary …

Investigations Of The Structure And Protein-Protein Interactions Of Chlamydia Trachomatis Scc4, Thilini Oshadhi Senarath Ukwaththage

LSU Doctoral Dissertations

Chlamydia trachomatis (CT) is the most common, sexually transmitted bacterial disease (STD) in the world. In the developmental cycle of CT, specific chlamydia chaperone 4 (Scc4) is a unique protein with essential and multiple roles. Hence, Scc4 is significant as a virulence target for therapeutic approaches to treat chlamydial infections. A novel approach was discovered to purify tag free Scc4 by utilizing a 6X-histidine-tag on Scc1 in the co-expressed Scc4:Scc1 complex by capturing the complex on nickel-charged immobilized metal affinity chromatography resin, followed by dissociation of Scc4 with sarkosyl. Using triple resonance NMR experiments, backbone and sidechain resonances …

Development Of Chemical Methods For Oligonucleotide Purification, Paramagnetic Labeling And Synthesis Of Dna-Based Advanced Materials, Muhan He

Legacy Theses & Dissertations (2009 - 2024)

This thesis describes a chemical method for alternative oligonucleotide purification that is non-chromatographic and gel-free and allows to routinely synthesize and purify long functional RNA strands. The purification of long RNAs is based on the bio-orthogonal inverse electron demand Diels-Alder (IEDDA) chemistry between trans-cyclooctene (TCO) and tetrazine (Tz). Target oligonucleotide strands are selectively tagged with Tz and can be captured and purified from the failure sequences with immobilized TCO. RNA strands are synthesized on solid support through a photolabile linker to avoid the loss of Tz tag. Purity of the isolated oligonucleotides was evaluated using gel electrophoresis, HPLC and mass …

Identification Of Ires Activity In Cellular Mrnas And Viral Rna Using A Circular Rna Construct, Priyanka Sehta

Legacy Theses & Dissertations (2009 - 2024)

Translation initiation is a critical step in the process of protein synthesis. The canonical way of translation initiation involves ribosomes being recruited to the 7-methyl guanosine cap present at the 5’end of the untranslated region (5’ UTR) of the RNAs. However, viral RNAs and some cellular mRNAs lack this 5’ cap structure and thus deploy an alternate non-canonical translation initiation mechanism. In non-canonical translation initiation, ribosome recruitment is facilitated by the RNA secondary structures called Internal Ribosome Entry Site (IRES) present most often in the 5’ UTR. To measure IRES-mediated translation, the dual luciferase assay has been the gold standard. …

Missense Mutations In The Gamma Crystallins And Mechanisms Of Lens Opacity, Wenjuan Hou

Legacy Theses & Dissertations (2009 - 2024)

Cataract, or clouding of the ocular lens, among the most common types of eye diseases, is the leading cause of blindness worldwide. With the opacity or clouding of the lens, light incident on the lens is scattered rather than being transmitted and is thus prevented from focusing on the retina. The lens becomes cataractous due to a large number of reasons, among which aging and genetic mutations are two of the most common factors. Clouding of the center of the lens or nuclear opacity, is the most frequently observed type of age-onset cataract, as well as inherited, congenital cataract [1, …

Degree Of Conservation Of Methionines Found To Be Oxidized In The Human Urinary Proteome, Alexis Hall

Graduate Theses and Dissertations

In previous work from this laboratory, methionine containing peptides from the human urinary proteome were examined by mass spectrometry for the degree of methionine oxidation to the sulfoxide form. While this demonstrated that many of the methionines detected were capable of being oxidized, the question of whether these methionines are important in the structure and/or function of the parent proteins came about. In some proteins, methionine oxidation has been linked to conformational changes and alteration of function and thus can serve as a mechanism for reversible regulation of activity. It is hypothesized that methionines which might serve a regulatory purpose …

Cloning, Protein Expression, And Characterization Of Interleukin 1 Alpha, Musaab Habeeb Ali Al Ameer

Graduate Theses and Dissertations

Recombinant DNA technology and the ability to produce recombinant proteins have significantly changed the world of pharmaceutical market. Recombinant DNA technology using E. coli cells has successfully produced many therapeutic proteins. In this study, the designed tag Ark-RUBY-tag facilitates rapid, and reproducible purification of recombinant proteins expressed as inclusion bodies in E. coli cells. Purification of Ark-RUBY-fused recombinant protein(s) can be obtained by using imidazole fractions. Target protein can be easily removed from the Ark-RUBY-tag by enzymatic cleavage. Ark-RUBY-fused recombinant proteins can be quantitatively detected using polyclonal antibodies. Ark-RUBY-tag can be used to purify small peptides. By using Ark-RUBY-tag, purified …

An Exploration Of Protein And Dna Components In Fingerprint Residue, Ashley Borrego

Student Theses

The main focus of this project was to investigate the protein and DNA components in both sebaceous and eccrine fingerprints. This study investigated the relative content of DNA and proteins in eccrine fingerprints to sebaceous fingerprints. All volunteers were instructed to wash and dry their hands prior to depositing parallel thumbprints. Twenty volunteers were instructed to touch their face to produce sebaceous prints, and 5 volunteers were instructed to wear gloves over a heat source to produce sweaty or eccrine prints. Microscopy was used to score the cellular debris of the right fingerprint on a scale of 1-4 based on …

Sers For Protein Detection At A Single Molecule Level For Developing A New Medical Diagnostics Platform, Lamyaa Almehmadi

Legacy Theses & Dissertations (2009 - 2024)

A two-step process of protein detection at a single molecule level using Surface Enhanced Raman Spectroscopy (SERS) was developed as a new platform for medical diagnostics in this proof-of-concept study. First, a protein molecule was bound to a linker in the bulk solution and then this adduct was chemically reacted with the SERS substrate. Traut’s Reagent (TR) was used to thiolate Bovine serum albumin (BSA) in solution followed by chemical cross linking to a gold surface through a sulfhydryl group. A Glycine-TR adduct was used as a control sample to identify the protein contribution to the SER spectra. Gold SERS …

Characterization Of The Microbial Phosphonate-Activating Pntc Enzymes, Kyle Rice

Theses and Dissertations (Comprehensive)

New strategies are urgently needed to combat infectious diseases in an era of rising antibiotic resistance. Furthermore, an emerging appreciation for the human microbiome’s role in maintaining health motivates discovery of species-specific antibiotics that minimally disrupt our native bacterial communities. Small molecule modifications to bacterial cell surfaces represent a potentially rich source of new targets for next generation antibiotics, as these molecules mediate virulence and evasion of the host immune response. Phosphocholine (PCho) is a rare cell surface modification that contributes to virulence, and modifications with phosphonates like 2-aminoethylphosphonate (AEP) are even more unusual and therefore provide opportunities for species- …

The Dissemination, Regulatory Role, And Evolution Of Mycobacterial Inteins, Danielle Skye Kelley

Legacy Theses & Dissertations (2009 - 2024)

Inteins are intervening protein elements, capable of coordinating escape from a host protein through a self-catalyzed mechanism, called protein splicing. This results in free intein and a mature host protein product. Inteins are also mobile elements and many contain homing endonucleases that enable the targeting to ectopic sites and invasion of novel niches. Inteins have been found across all three domains of life and are often present in replication, recombination, and repair proteins. However, it is unclear if the observed distribution is simply a factor of endonuclease preference or if inteins have been selectively maintained due to an adaptation that …

2-D Electrophoresis Modeling Of Multienzyme Cutting Of Polypeptides, Howard Mayes

Theses

2-Dimensional Electrophoresis is one of the tools in the identification of proteins by molecular weight and pH. The display of molecular weight allows the researcher to quickly identify whether a specific protein or peptide string is in the sample. The pH measurement allows even better resolution between different species in the sample. The MultiEnzyme ElectroPhoresis (MEEP) program tries to model that by providing a graph that displays separated protein strings by both molecular weight and pH. The ability to cleave the protein with 43 different enzyme variations allows the researcher to analyze appropriate enzymes to isolate a protein subsequence before …

Use Of Crispr To Develop A Follicle Stimulating Hormone Receptor Knockout In Human Granulosa Cells To Study Lipid Raft Residency, Jenna Pradhuman

Honors Theses

Human follicle stimulating hormone (hFSH) is a protein hormone responsible for stimulating the gonads and is necessary for regulating reproductive systems in both females and males. The actions of hFSh are carried out by the hFSH receptor (hFSHR), a seven transmembrane receptor that belongs to the G protein-coupled receptor family. Once FSH activates its receptor, the G protein inside the cell that is associated with the receptor is activated and starts a cascade of signaling that results in activation of protein kinase A (PKA) and the p44/42 MAP kinase (MAPK). The activation of these secondary proteins is responsible for follicular …

Study Of Biologically Important Macromolecules By Nuclear Magnetic Resonance, Christopher Michael Demott

Legacy Theses & Dissertations (2009 - 2024)

Intrinsically disordered proteins or unstructured segments within proteins play an important role in cellular physiology and pathology. A combination of peptide aptamers selected by using the yeast-two-hybrid scheme, and in-cell NMR identified high affinity binders to a transiently structured intrinsically disordered proteins (IDP). This method was validated using the prokaryotic ubiquitin-like protein, Pup, of the Mycobacterium proteasome. We discover two peptide aptamers that bind to opposite sites of a transient helix in Pup, an intrinsically disordered protein, that have vastly different effects on the survival of Mycobacterium bovis BCG.

Using Simple Self-Assembling Peptides To Attain Novel Protein-Like Functions, Tyler Smith

Renée Crown University Honors Thesis Projects - All

Proteins carry out many extremely efficient functions, including catalysis and biomolecule recognition. Underlying this efficiency is their extraordinary complexity and ability to fold into unique three-dimensional structures. Attempts to replicate this efficiency through de novo design have only shown moderate success, and it is unclear how modern-day proteins may have evolved. However, short peptides that alternate hydrophobic and hydrophilic residues can self-assemble into amyloid fibrils to achieve well-defined secondary structure. These aggregates may have served as a template from which the first proteins were derived. We designed self-assembling seven-residue peptides that are able to act as Zn²⁺-dependent esterases. …

A Survey Of The Current Drug Screening Techniques To Obtain Rational Design And Study Drug-Target Interactions, Stephen Dansereau

Legacy Theses & Dissertations (2009 - 2024)

Different techniques have been developed over the years for the purpose of studying proteins and understanding their functions. Early techniques typically employed bioluminescence or fluorescence such such as the firefly protein luciferase and the jellyfish green fluorescent protein (GFP), respectively, to localize proteins within the cell. X-ray crystallography has also provided valuable structural details of many different proteins in vitro. Yet, nuclear magnetic resonance (NMR) spectroscopy offers the most realistic insight into proteins' physiologic structures and how proteins function in their native, cellular environments.

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 …

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 …

Novel Nmr Based Technologies To Study Macromolecular Structures, Subhabrata Majumder

Legacy Theses & Dissertations (2009 - 2024)

Nuclear Magnetic Resonance Spectroscopy (NMR) is one of the principle tools in structural biology to probe macromolecular structures and interactions. The atomic resolution afforded by this technique has been widely used to probe protein-protein, and protein-ligand interactions in-vitro. However, the natural milieu of the proteins is the living cell and the cellular cytoplasm is extremely heterogeneous. The NMR studies of folded protein in-cell, till now, have been limited by non-specific interactions of the cytosol. This thesis outlays a general methodology to study protein structure/interactions inside the living cells using NMR. In a closely related objective, it also describes the use …

Expression In Yeast Of The Metacaspase Scp3 From The Fungus Schizophyllum Commune, Anne Kaminski

Honors Theses

Metacaspases are caspase homologs that are found in plants, fungi, and protists. They are involved in programmed cell death, a structured and regulated process to break down cells. There is limited information available on metacaspases and further research is necessary to understand how they work. One reason metacaspases are studied is that they are considered to be a potential drug target for pathogenic microorganisms. Five metacaspases scp1-5 were identified in S. commune through their similarity to the yeast metacaspase Yca1. The overall goal of the lab is to study and characterize these proteins. This thesis outlines the path taken to …

New Tools To Study Amyloid Fibrils And Intrinsically Disordered Proteins In Vitro And In Vivo, Jacqueline D. Washington

Legacy Theses & Dissertations (2009 - 2024)

Amyloid fibrils are β-sheet-rich protein aggregates commonly found in the organs and tissues of patients with various amyloid-associated diseases. The structure of insulin fibrils was characterized by deep ultraviolet resonance Raman and Nuclear Magnetic Resonance spectroscopy combined with hydrogen-deuterium exchange. Our new approach of combining NMR and Raman spectroscopy with molecular dynamic simulations for characterizing amyloid fibrils provided exclusive knowledge about fibril structure at amino acid residue resolution.

Protein Structures Under Physiological Conditions, Karl Michael Bertrand

Legacy Theses & Dissertations (2009 - 2024)

My research focused on the evaluation of protein structures and protein dynamics inside eukaryotic cells under physiological conditions. The primary analyses of my research involved the use of in-cell Nuclear Magnetic Resonance spectroscopy using Heteronuclear Single Quantum Coherence experiments. This allowed me to visualize protein structures at an atomic resolution level, as well as, study the interactions of these proteins with small molecules.

Minireview: Protein Interactions, Jessica Child

Honors Theses and Capstones

No abstract provided.