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Protein Stability In Solution And In The Gas Phase., Yousef Haidar
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 …
Molecular Simulation Of Rna Conformational Dynamics : An Example Of Micro-Rna Targeting Messenger Rna : Mir-34a-Msirt1, Parisa Ebrahimi
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
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 …
Missense Mutations In The Gamma Crystallins And Mechanisms Of Lens Opacity, Wenjuan Hou
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, …
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 …
An Exploration Of Protein And Dna Components In Fingerprint Residue, Ashley Borrego
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
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
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- …
2-D Electrophoresis Modeling Of Multienzyme Cutting Of Polypeptides, Howard Mayes
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 …
Study Of Biologically Important Macromolecules By Nuclear Magnetic Resonance, Christopher Michael Demott
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.
The Application Of Hydrogen/Deuterium Exchange And Covalent Labeling Coupled With Mass Spectrometry To Examine Protein Structure, Nicholas B. Borotto
The Application Of Hydrogen/Deuterium Exchange And Covalent Labeling Coupled With Mass Spectrometry To Examine Protein Structure, Nicholas B. Borotto
Doctoral Dissertations
Thorough insight into a protein’s structure is necessary to understand how it functions and what goes wrong when it malfunctions. The structure of proteins, however, is not easily analyzed. The analysis must take place under a narrow range of conditions or risk perturbing the very structure being probed. Furthermore, the wide diversity in size and chemistry possible in proteins significantly complicates this analysis. Despite this numerous methods have been developed in order to analyze protein structure. In this work, we demonstrate that mass spectrometry (MS)-based techniques are capable of characterizing the structure of particularly challenging proteins. This is done through …
Distinguishing Macrophage Activation States By Mass Spectrometry, Matthias Manfred Knust
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
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 …
Identification Of Persistent Long Range Interactions In GA95 And GB95 Through Thermal Unfolding Simulations, Milen Redai Tesfamariam
Identification Of Persistent Long Range Interactions In GA95 And GB95 Through Thermal Unfolding Simulations, Milen Redai Tesfamariam
Chemistry & Biochemistry Theses & Dissertations
For over five decades, different experiments have been performed to research how proteins attain their native three dimensional structures. However, the folding problem continues to be a puzzle in modern science. The design of two proteins that have maximal sequence identity but different folds and functions is one method that is being used to study the relationship between protein structure and amino acid sequence. In particular, mutant proteins of Streptococcus protein G, GA and GB, have 95% sequence identity and a 3a helix fold and β4/a fold, respectively. Molecular dynamics simulations of GA95 …
Structural Interactions And Dynamics Of Disease Related Proteins By Using Nmr Spectroscopy, Shadakshara Swamy Puttamadappa
Structural Interactions And Dynamics Of Disease Related Proteins By Using Nmr Spectroscopy, Shadakshara Swamy Puttamadappa
Legacy Theses & Dissertations (2009 - 2024)
Nuclear Magnetic Resonance (NMR) is a powerful spectroscopic technique to study the structure, molecular interactions, and dynamics of proteins. Modern NMR instrumentation, advancements in experimental techniques and revolutionary developments in recombinant DNA technology have made NMR a versatile and very convenient tool for biomolecule characterization.
Elucidating The Structure Of Protein Aggregates By Raman Spectroscopy, Ludmila A. Popova
Elucidating The Structure Of Protein Aggregates By Raman Spectroscopy, Ludmila A. Popova
Legacy Theses & Dissertations (2009 - 2024)
The structures and properties of amyloid fibrils are of considerable interest due to their associations with numerous neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease and transmissible spongiform encephalopaties (prion diseases). Understanding fibrillogenesis at a molecular level requires detailed structural characterization of amyloid fibrils. However amyloid fibrils are difficult objects to study due to their non-crystalline and insoluble nature. These properties make the application of classical tools of structural biology, such as X-Ray crystallography and solution Nuclear Magnetic Resonance spectroscopy, impractical for structural characterization of protein fibrils.
Dna-Templated Nanomaterials, Hector Alejandro Becerril-Garcia
Dna-Templated Nanomaterials, Hector Alejandro Becerril-Garcia
Theses and Dissertations
Nanomaterials display interesting physical and chemical properties depending on their shape, size and composition. Self assembly is an intriguing route to producing nanomaterials with controllable compositions and morphologies. DNA has been used to guide the self assembly of materials, resulting in: (1) metal nanowires; (2) metal or semiconductor nanorods; (3) carbon nanotubes; and (4) semiconductor, metal or biological nanoparticles. My work expands the range of DNA templated nanomaterials and develops novel ways of using DNA to pattern nanostructures on surfaces. I have performed the first synthesis of silver nanorods on single stranded DNA, an attractive material for localizing DNA coupled …
Development Of Polymer Monoliths For The Analysis Of Peptides And Proteins, Binghe Gu
Development Of Polymer Monoliths For The Analysis Of Peptides And Proteins, Binghe Gu
Theses and Dissertations
Several novel polymer monoliths for the analysis of peptides and proteins were synthesized using polyethylene glycol diacrylate (PEGDA) as crosslinker. Photo-initiated copolymerization of polyethylene glycol methyl ether acrylate and PEGDA yielded an inert monolith that could be used for size exclusion liquid chromatography of peptides and proteins. This macroscopically uniform monolith did not shrink or swell in either water or tetrahydrofuran. More importantly, it was found to resist adsorption of both acidic and basic proteins in aqueous buffer without any organic solvent additives. A strong cation-exchange polymer monolith was synthesized by copolymerization of 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) and PEGDA. A ternary …
Capillary Electrophoresis Of Proteins With Selective On-Line Affinity Monoliths, Jenny Marcela Armenta Blanco
Capillary Electrophoresis Of Proteins With Selective On-Line Affinity Monoliths, Jenny Marcela Armenta Blanco
Theses and Dissertations
The analysis of proteins in biological fluids by capillary electrophoresis (CE) is of interest in clinical chemistry. However, due to low analyte concentrations and poor concentration limits of detection (CLOD), protein analysis by this technique is frequently challenging. Coupling preconcentration techniques with CE greatly improves the CLOD. An on-line preconcentration-CE method that can selectively preconcentrate any protein for which an antibody is available would be very useful for the analysis of low abundance proteins and would establish CE as a major tool in biomarker discovery. To accomplish this, an on-line protein G monolithic preconcentrator CE system for enrichment and separation …
Polymer Microchips For Capillary Electrophoresis And Electric Field Gradient Focusing Of Biomolecules, Ryan Thomas Kelly
Polymer Microchips For Capillary Electrophoresis And Electric Field Gradient Focusing Of Biomolecules, Ryan Thomas Kelly
Theses and Dissertations
Polymeric materials have seen increasing use as microfluidic device substrates due to their low cost and the simplicity of templated fabrication procedures. I showed that poly(methyl methacrylate) (PMMA) microdevices could be enclosed in a boiling water bath, which allowed the seal to form more quickly than in conventional approaches, and enabled microchannels to remain hydrated throughout the bonding process. Microchip capillary electrophoresis (µ-CE) devices were fabricated using water-based enclosure, and a mixture of fluorescently labeled amino acids was separated in 30 s in these microchips. To create more robust capillary electrophoresis (CE) microdevices with improved separation performance, phase-changing sacrificial materials …