Chemistry Commons^™

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 …

Structural Analysis Of Protein Therapeutics Using Covalent Labeling – Mass Spectrometry, Patanachai Limpikirati

Doctoral Dissertations

Using mass spectrometry (MS) to obtain information about a higher order structure of protein requires that a protein’s structural properties are encoded into the mass of that protein. Covalent labeling (CL) with reagents that can irreversibly modify solvent accessible amino acid side chains is an effective way to encode structural information into the mass of a protein, as this information can be read-out in a straightforward manner using standard MS-based proteomics techniques. The differential reactivity of proteins under two or more conditions can be used to distinguish protein topologies, conformations, and/or binding sites. CL-MS methods have been effectively used for …

Analysis Of Oxidatively Damaged Proteins By Mass Spectrometry, Vincent Saullo

Electronic Thesis and Dissertation Repository

As humans age, exposure to oxidative stress may induce protein degradation or aggregation; both resulting in loss of protein function. Protein oxidative damage remains a dominant pathology in many common ailments. To combat these pathologies, scientists must understand the nature of oxidative modifications and their effects on protein structure and dynamics. This work employs a range of mass spectrometry (MS) methods to characterize and analyze the effects of oxidative damage on the model protein myoglobin (Mb). Mb was oxidized using tert-butyl hydroperoxide, and the resulting modifications were characterized by top-down and bottom-up MS workflows. Hydrogen/deuterium exchange MS indicated elevated structural …

I3: Isomerization Of Isomer Ions, Krisztián Gabor Torma

University of the Pacific Theses and Dissertations

Photoelectron Photoion Coincidence (PEPICO) spectroscopy is a robust tool for elucidating complex unimolecular dissociation mechanisms and for determining thermochemical and kinetic data of gas-phase ion dissociations with high accuracy. In this work, the dissociative photoionization of two sets of isomeric systems were analyzed with PEPICO: 1) C7H7+ ions of toluene (Tol) and 1,3,5-cycloheptatriene (CHT), and 2) two butyl alcohol isomers, 1-butanol and isobutanol. Threshold dissociative photoionization data on these four molecules of interest were collected on the imaging PEPICO apparatus at the VUV beamline of the Swiss Light Source. Data analysis was aided by ab initio calculations and Rice-Ramsperger-Kassel-Marcus (RRKM) …

Multidimensional Mass Spectrometry Of Chemonic™ Ccg-6 Nonionic Surfactant With Separation By Polarity And Shape, Charles Johnson

Williams Honors College, Honors Research Projects

Chemonic™ CCG-6 surfactant is a water-soluble poly(ethylene glycol) (PEG) conjugated alkyl glyceride emollient. This surfactant exists as a complex mixture of a glycerol cores conjugated with poly(ethylene glycol) branches (PEGylation) that were partially esterified with caprylic (C8) and capric (C10) acids. These may be esterified on one, two, or all three arms of the glyceride. The architecture of the structures in this mixture was studied using multidimensional mass spectrometry (MS). Mass spectrometry was interfaced with ultra-performance liquid chromatography (UPLC) and ion mobility (IM) separation. The mixture was separated by reversed-phase LC, oligomers of the star-branched polymer were separated according to …

Integrated Proteotranscriptomics Of Breast Cancer Reveals Globally Increased Protein-Mrna Concordance Associated With Subtypes And Survival, Wei Tang, Ming Zhou, Tiffany H Dorsey, Darue A Prieto, Xin W Wang, Eytan Ruppin, Timothy Veenstra, Stefan Ambs

Pharmaceutical Sciences Faculty Publications

BACKGROUND: Transcriptome analysis of breast cancer discovered distinct disease subtypes of clinical significance. However, it remains a challenge to define disease biology solely based on gene expression because tumor biology is often the result of protein function. Here, we measured global proteome and transcriptome expression in human breast tumors and adjacent non-cancerous tissue and performed an integrated proteotranscriptomic analysis.

METHODS: We applied a quantitative liquid chromatography/mass spectrometry-based proteome analysis using an untargeted approach and analyzed protein extracts from 65 breast tumors and 53 adjacent non-cancerous tissues. Additional gene expression data from Affymetrix Gene Chip Human Gene ST Arrays were available …

Fatty Acid Biomarker Detection For Breast Cancer Using Differential Mobility Spectrometry With Non-Radioactive Ion Source, James Joseph Alberti

USF Tampa Graduate Theses and Dissertations

Differential Mobility Spectrometry (DMS) using a non-radioactive ion source (NRIS) is investigated as a possible medical diagnostic instrument for near real-time detection of breast cancer biomarkers. In previous clinical studies, concentrations of Linoleic, Palmitic and Stearic fatty acids have been observed at different levels in women with carcinoma breast cancer versus women with benign tumors or healthy women showing no signs of breast cancer. Present diagnostic methods require a biopsy of the suspect tissue and a microscopic lab analysis performed to determine its disease state. This process can take hours or days before the patient and doctor are informed of …

Identification And The Significance Of Selective Proteins In Bile And Plasma Of Normal And Health-Compromised Chickens, Balamurugan Packialakshmi

Graduate Theses and Dissertations

During the last 50 years, animal breeding programs in commercial poultry have made significant progress in the bodyweight gain of broilers but led to several metabolic and skeletal disorders. Lameness associated with proximal femur known as femoral head separation (FHS) or femoral head necrosis (FHN) is one of the major metabolic disorders in poultry industry. In order to select for healthy chickens, markers that can distinguish between healthy and affected birds are required. Biomarkers from blood represent an ideal and rich source of markers which can be obtained using minimally invasive methods. The biomarkers were explored in an experimental model …

Quantitative Mass Spectrometric Investigations Of Protein Biomarkers: Serum Thymidine Kinase 1 And Human Osteopontin, Morse Faria

Theses and Dissertations

Mass spectrometry is being increasingly used in biomarker research mainly due to its ability to achieve high selectivity coupled with high sensitivity. This dissertation focuses on quantitative mass spectrometric investigations of two protein biomarkers i.e. serum thymidine kinase 1 (TK1) and human osteopontin (OPN).

First part of this research was focused on developing a liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) method for measuring the activity of TK1 in serum by monitoring the conversion of a TK1 specific exogenous substrate, 3’-deoxy-3’-fluorothymidine (FLT), to its mono-phosphorylated form 3’-deoxy-3’-fluorothymidine monophosphate (FLT-MP). A method to quantify FLT-MP on LC-MS/MS was developed and …

Rat Brain Pro-Oxidant Effects Of Peripherally Administered 5 Nm Ceria 30 Days After Exposure, Sarita S. Hardas, Rukhsana Sultana, Govind Warrier, Mo Dan, Rebecca L. Florence, Peng Wu, Eric A. Grulke, Michael T. Tseng, Jason M. Unrine, Uschi M. Graham, Robert A. Yokel, D. Allan Butterfield

Chemistry Faculty Publications

The objective of this study was to determine the residual pro-or anti-oxidant effects in rat brain 30 days after systemic administration of a 5 nm citrate-stabilized ceria dispersion. A ∼4% aqueous ceria dispersion was iv-infused (0 or 85 mg/kg) into rats which were terminated 30 days later. Ceria concentration, localization, and chemical speciation in the brain was assessed by inductively coupled plasma mass spectrometry (ICP-MS), light and electron microscopy (EM), and electron energy loss spectroscopy (EELS), respectively. Pro- or anti-oxidant effects were evaluated by measuring levels of protein carbonyls (PC), 3-nitrotyrosine (3NT), and protein-bound-4-hydroxy-2-trans-nonenal (HNE) in the hippocampus, cortex, and …

Explorations In Homeoviscous Adaptation And Mass Spectral Analysis Of Membrane Lipids, Michael Douglas Timmons

University of Kentucky Doctoral Dissertations

The focus of this dissertation is centered on the mass spectral analysis of lipids and changes occurring in keeping with the concept of homeoviscous adaptation [1]. Homeoviscous adaptation is the process of modification of membrane lipids in response to environmental stimuli [1]. Dissertation investigations applied this concept to prokaryotic and eukaryotic organisms, and expanded the perception of environmental factors from exogenous organic solvents to intracellular environment.

The field of lipidomics deals with the analysis of phospholipid and fatty acid components of membranes the changes that occur due to environmental stimuli and their biological significance [2-6]. The high sensitivity of mass …