Biochemistry Commons^™

Nbpmf: Novel Network-Based Inference Methods For Peptide Mass Fingerprinting, Zhewei Liang

Electronic Thesis and Dissertation Repository

Proteins are large, complex molecules that perform a vast array of functions in every living cell. A proteome is a set of proteins produced in an organism, and proteomics is the large-scale study of proteomes. Several high-throughput technologies have been developed in proteomics, where the most commonly applied are mass spectrometry (MS) based approaches. MS is an analytical technique for determining the composition of a sample. Recently it has become a primary tool for protein identification, quantification, and post translational modification (PTM) characterization in proteomics research. There are usually two different ways to identify proteins: top-down and bottom-up. Top-down approaches …

Mass Spectrometry-Based Structural Proteomics: Methodology And Application Of Fast Photochemical Oxidation Of Proteins (Fpop), Ben Niu

Arts & Sciences Electronic Theses and Dissertations

The dissertation will be solely focused on using mass spectrometry to characterize protein high order structures (HOS), it emphasizes the use of hydroxyl radical footprinting (FPOP) coupled to bottom-up MS approach. A detailed background information about FPOP, and the corresponding method developments as well as applications will be covered.

The first chapter will be a comprehensive review regarding the FPOP. Following this, chapter 2, 3, and 4 will be focused on the method developments. Chapter 2 describes an isotope dilution GC-MS method to quantitate OH radicals in FPOP; chapter 3 describes the incorporation of Leu-enkephalin as reporter peptide for a …

Detection, Diversity, And Evolution Of Fungal Nitric Oxide Reductases (P450nor), Steven Adam Higgins

Doctoral Dissertations

Nitrous oxide (N₂O) is a gas responsible for significant ozone layer depletion and contributes to greenhouse effects in Earth’s atmosphere. N₂O is primarily generated by denitrification, whereby nitrate (NO_3-) or nitrite (NO_2-) is converted to gaseous N₂O or N2. Teragram quantities of N₂O are emitted annually from agricultural soils treated with nitrogenous fertilizers due to the activity of soil microbiota. Although bacteria and fungi harbor genes permitting denitrification, fungi lack NosZ, an enzyme responsible for reducing N₂O into inert N2 gas. Historically, scientists have linked fungi …

Mapping Analyte-Signal Relations In Lc-Ms Based Untargeted Metabolomics, Nathaniel Guy Mahieu

Arts & Sciences Electronic Theses and Dissertations

The goal of untargeted metabolomics is to profile metabolism by measuring as many metabolites as possible. A major advantage of the untargeted approach is the detection of unexpected or unknown metabolites. These metabolites have chemical structures, metabolic pathways, or cellular functions that have not been previously described. Hence, they represent exciting opportunities to advance our understanding of biology. This beneficial approach, however, also adds considerable complexity to the analysis of metabolomics data - an individual signal cannot be readily identified as a unique metabolite. As such, a major challenge faced by the untargeted metabolomic workflow is extracting the analyte content …

Biophysical Studies Of Hairpin Polyamides With Broad-Spectrum Activity Against High-Risk Human Papillomaviruses, Carlos H. Castaneda

Dissertations

Human papillomavirus is a small dsDNA virus that infects mucosal and cutaneous epithelial tissues. Persistent infection with high-risk HPV is the main etiological agent in the development of cervical cancer worldwide. Although prophylactic vaccines against HPV are available, these preventative measures are type-specific and are ineffective against existing infections. Thus, there is a pressing need for antiviral drugs with a broad-spectrum activity against HPV to eradicate existing infections, no matter the subtype.

Our group and collaborators have synthesized an extensive library of novel N-methylpyrrole/N-methylimidazole (Py/Im) hairpin polyamides (PAs) with broad-spectrum activities against three prevalent oncogenic-HPV types (HPV16, …

Chloride And Proton Binding In The E. Coli 2cl¯:1h+ Clc Exchanger, Catherine Chenal

Dissertations, Theses, and Capstone Projects

The CLC family of membrane proteins is a ubiquitously expressed class of proton and usually voltage-activated chloride transporters involved in a myriad of physiological functions. Crystallographic structures identify up to three chloride binding sites: external, central and intracellular located in the inner half of the trans-membrane domain. The CLC proteins, except for the kidney isoforms, are gated by the extracellular side-facing gating Glutamate (Ex, E148 in CLC-ec1, the E. coli exchanger), which is thought to undergo a conformational change upon protonation.

To sort out how the thermodynamic paths to H+ coupled Cl¯ binding and conformational change in CLC-ec1 at the …

Functional Analysis Of Sin3 Isoforms In Drosophila, Nirmalya Saha

Wayne State University Dissertations

he multisubunit SIN3 complex is a global transcriptional regulator. In Drosophila, a single Sin3A gene encodes different isoforms of SIN3, of which SIN3 187 and SIN3 220 are the major isoforms. Previous studies have demonstrated functional non-redundancy of SIN3 isoforms. The role of SIN3 isoforms in regulating distinct biological processes, however, is not well characterized. In addition, how the components of the SIN3 complex modulate the gene regulatory activity of the complex is not well understood. In this study, I identified the biological processes regulated by the SIN3 isoforms. Additionally, I explored how Caf1-55 impacts the gene regulatory activity of …

Micro-Spectroscopy Of Bio-Assemblies At The Single Cell Level, Jeslin Kera

Honors Undergraduate Theses

In this thesis, we investigate biological molecules on a micron scale in the ultraviolet spectral region through the non-destructive confocal absorption microscopy. The setup involves a combination of confocal microscope with a UV light excitation beam to measure the optical absorption spectra with spatial resolution of 1.4 μm in the lateral and 3.6 μm in the axial direction. Confocal absorption microscopy has the benefits of requiring no labels and only low light intensity for excitation while providing a strong signal from the contrast generated by the attenuation of propagating light due to absorption. This enables spatially resolved measurements of single …

Investigation Of The Mechanism Of Action For Mithramycin And The Biosynthesis Of L-Rednose In Saquayamycins, Stevi Weidenbach

Theses and Dissertations--Pharmacy

Natural products continue to be a major chemical lead matter for drug discovery due to their diverse chemical structures and bioactivities. Clinically significant natural products include anti-cancer and anti-infective compounds and while many more of these compounds show promising bioactivity, their clinical relevance is often limited by toxicity or poor solubility. Combinatorial biosynthesis can be employed to modify existing chemical scaffolds towards reducing these limitations. To fully take advantage of these biochemical tools, it is important to understand the biosynthesis and mechanism of action of the molecules.

Saccharides in glycosylated natural products provide specific interactions with cellular targets and are …